Part 5
, pages 409-441 _in_ Soviet fisheries investigations in the northeastern Pacific Ocean. (Transl. from Russian.) Israel Program for Scientific Translations, Jerusalem.
Sanger, G. A. 1972. Preliminary standing stock and biomass estimates of seabirds in the subarctic Pacific region. Pages 499-611 _in_ A. Y. Takenouti, ed. Biological oceanography of the northern north Pacific Ocean.
Serobaba, I. I. 1968. On the spawning of Alaska pollock _Theragra chalcogramma_ (Pallas) in the northeastern part of the Bering Sea. Vopr. Ikhtiol. 6(53):992-1003. (Transl. from Russian.) Israel Program for Scientific Translations, Jerusalem.
Shaefer, M. B. 1970. Men, birds, and anchovies in the Peru current--dynamic interactions. Trans. Am. Fish. Soc. 99(3):461-467.
Shuntov, V. P. 1961. Migration and distribution of marine birds in the southeastern Bering Sea during spring-summer season. Zool. Zh. 40(7):1058-1069. (In Russian, summary in English.)
Shuntov, V. P. 1966. Concerning wintering of birds in the far eastern seas and in the northern part of the Pacific Ocean. Zool. Zh. 45(11):698-711. (Transl. from Russian.) Can. Wildl. Serv.
Solomensen, F. 1965. The geographical variation of the fulmar _(Fulmarus glacealis)_ and the zones of marine environment in the North Atlantic. Auk 82:327-355.
Stevenson, J. C. 1962. Distribution and survival of herring larvae (_Clupea pallasi_ Valenciennes) in British Columbia waters. J. Fish. Res. Board Can. 19(5):735-810.
Straty, R. R. 1974. Ecology and behavior of juvenile sockeye salmon _(Oncorhynchus nerka)_ in Bristol Bay and the eastern Bering Sea. Inst. Mar. Sci., Univ. Alaska, Occas. Publ. 2:285-320.
Tanino, Y., H. Tsujisaki, K. Nakamichi, and K. Kyushin. 1959. On the maturity of Alaska pollock, _Theragra chalcogramma_ (Pallas). Bull. Hokkaido Reg. Fish. Res. Lab. 20:145-164.
Taylor, F. H. C. 1967. The relationship of midwater trawl catches to sound scattering layers off the coast of northern British Columbia. J. Fish. Res. Board Can. 25(3):457-472.
Tuck, L. M. 1960. The murres: their distribution, populations, and biology, a study of the genus _Uria_. Can. Wildl. Ser. 1. 260 pp.
Wiens, J. A., and J. M. Scott. 1976. Model estimation of energy flow in Oregon coastal seabird populations. Condor 77(4):439-452.
Yusa, T. 1954. On the normal development of the fish, _Theragra chalcogramma_ (Pallas), Alaska pollock. Bull. Hokkaido Reg. Fish. Res. Lab. 10. 15 pp.
FOOTNOTES:
[54] For crabs, this measurement is carapace width.
[55] Authors' data.
[56] For crabs, the measurements are total length for zoeal stages and carapace length and width for postzoeal stages.
[57] The incubation period for an egg is temperature dependent. Embryo development is faster at higher temperatures.
[58] Juvenile pollock have diurnal migrations.
[59] The peak period varies with latitude: to 55°N--June; to 55-60°N--July; to north of 60°N--August.
[60] H. R. Carlson and R. E. Haight (in preparation), Juvenile life of Pacific ocean perch, _Sebastes alutus_, in coastal fiords of southeastern Alaska: their environment, growth, food habits, and schooling behavior.
[61] The genus _Sebastes_ is a live bearer.
[62] Rockfish larvae resemble each other quite closely, and complete descriptions for the 10 species in the Bering Sea do not exist. The following depth distribution for rockfish larvae may or may not include _S. alutus_: 45-365 m (Taylor 1967) off British Columbia; 0-88 m (Ahlstrom 1959, 1961) off California and Baja California.
[63] In crabs, the eggs are attached to the female.
[64] S. C. Jewett and R. E. Haight (in preparation), A description of megalopa of the snow crab, _Chionoecetes bairdi_ Rathbun (Majidae, subfamily Oregoniinae).
[65] Spawning occurs in May in the eastern Bering Sea, but the total period is not known.
Interrelations Between Seabirds and Introduced Animals
by
Robert D. Jones, Jr.
U.S. Fish and Wildlife Service 1011 East Tudor Road Anchorage, Alaska 99507
and
G. Vernon Byrd[66]
U.S. Fish and Wildlife Service Aleutian Islands National Wildlife Refuge Adak, Alaska
Abstract
Animals introduced to insular seabird habitats are of both intentional and accidental origin. The results of the introductions--particularly of herbivores--cannot be predicted, but may range from severely destructive to beneficial. Herbivores are of both domestic and wild stocks of ungulates, hares, and rabbits. Rats are the most commonly introduced omnivore on a worldwide basis. In Alaska the commonest carnivore introduction has been the red fox _(Vulpes fulva)_ and arctic fox _(Alopex lagopus)_, and the first of these were made in the early 19th century by the Russian-American Company. These foxes nearly extirpated the Aleutian Canada goose _(Branta canadensis leucopareia)_ from its nesting grounds. Black flies (Simuliidae), which are vectors of avian blood parasites, have been introduced to three of the Aleutian Islands.
The purpose of this paper is to discuss some influences of introduced animals, primarily mammals, on seabirds and their nesting habitat, with emphasis on the coasts of Washington, British Columbia, and Alaska. Our discussion focuses on island introductions partly because a large proportion of seabirds choose island nesting sites, and because islands present ecosystems vulnerable to such introductions.
Flightless animals have no means of immigration, hence little probability of colonizing islands. In these circumstances marine birds evolve populations in relatively simple ecosystems (Carlquist 1965; MacArthur and Wilson 1967), though the degree of simplicity depends on several variables, including the island's size and its distance from a source of immigrants. These systems have achieved ecological homeostasis through reciprocal adaptation over an extended period. Experience has shown that introductions to such systems result in severe perturbations (Odum 1971:221).
The introductions can be categorized as being either intentional or accidental events. Effects of such introductions have varied widely, depending on the type of animal introduced, the types of birds present and the habitat they occupy, the size and shape of the island, the type of nesting area used by the birds, and the status of their populations before the introduction. An example drawn from our Aleutian experience with gallinaceous birds illustrates the interaction of these variables. The dark phase of the arctic fox _(Alopex lagopus)_ was introduced to Adak and Amchitka islands, both of which had native populations of the rock ptarmigan, _Lagopus mutus_ (Gabrielson and Lincoln 1959). Foxes were released on Adak in 1924, and on Amchitka in 1921. Adak has an area of 751 km² and Amchitka 350 km². Adak is irregular in shape with extensive precipitous shorelines, relatively few beaches, and a large, central mountainous hinterland which foxes rarely penetrated. Amchitka, on the other hand, presents a zone of marine planation on its eastern two thirds, low mountains on the rest, shelving beaches around most of the island, and a long, linear, narrow shape that foxes explored completely. By 1949 ptarmigan were difficult to find on Amchitka, and then only in the highest, steepest section of the mountains. They were extirpated from the low, eastern two thirds of the island. The foxes flourished on Amchitka, but did much less well on Adak, where the ptarmigan population fluctuated in a normal cyclic manner, apparently uninfluenced by the foxes. Then the foxes were eradicated on Amchitka in the 1950's, and by 1962 the ptarmigan had spread over the whole of the island and become one of the most conspicuous avian features of the landscape.
Animal Introductions
_Non-predatory Animals_
Man has taken ungulates with him to many islands. Although numerous records of livestock introductions are available, few provide information relating to the effects of these animals on the habitat and their fauna unless the impact has been severe.
A most noteworthy example of destruction by ungulates occurred on Guadalupe Island off the coast of Baja California. Domestic goats _(Capra hircus)_ were introduced in the unrecorded past with the result that little of the once abundant vegetation remains. In its place introduced species capable of withstanding heavy grazing are abundant over most of the island. Several endemic avian species are now considered extinct, including the Guadalupe storm-petrel, _Oceanodroma macrodactyla_ (Howell and Cade 1954; Jehl 1972).
Sheep _(Ovis aries)_ have been introduced to seabird nesting islands with varying results. In Bass Strait, Australia, Norman (1970) studied the effects of introduced sheep on vegetation and birds. He cited various papers attributing destruction of colonies of shearwaters (_Puffinus_ sp.) to the activities of sheep, primarily their treading on the burrows. He found, however, that on Big Green Island and Phillip Island, sheep were not responsible for declines in shearwater breeding success, nor did they prevent expansion of colonies.
Other authors have reported damage to seabird nesting areas by sheep. One such example in the eastern North Pacific region concerns Protection Island, Washington. According to Richardson (1961), 100 to 300 sheep grazed freely on the island since 1958. He reported damage by grazing and frequent trampling of nesting areas of rhinoceros auklets _(Cerorhinca monocerata)_. Landslides were initiated by these
## activities, rendering the slopes unusable by auklets. Of the burrows
in his study area, 46% were buried by slides. He did not determine mortality.
Other avian consequences may flow from sheep introductions. Husbandry of these ungulates has been practiced with varying success for many years in the Aleutian Islands, most notably on Umnak and Unalaska islands, both of which have large native populations of bald eagles, _Haliaeetus leucocephalus_ (Gabrielson and Lincoln 1959). Before the introduction of sheep, these raptors were oriented to the sea, hunting fish and seabirds. Sheep presented a new resource and presently the industry found itself confronted by a formidable predator, and demanded that eagles be destroyed (letter to William Egan, Governor of Alaska, from James S. Bynum, Secretary-treasurer, Umnak Company, Inc.).
Other ungulates introduced on Alaska islands include cattle _(Bos taurus)_ on Chernofski and Chernabura islands; caribou _(Rangifer tarandus)_ on Adak; reindeer on St. Matthew, Nunivak, Atka, Umnak, St. Paul, St. Lawrence, Hagemeister, and Kodiak as well as many interior locations; deer _(Odocoileus hemionus)_ on Kodiak and Afognak; elk _(Cervus canadensis)_ on Afognak; and musk oxen _(Ovibos moschatus)_ on Nunivak. All these animals have maintained populations on islands for a time, and some appear likely to do so into the distant future. Specific effects on seabirds is generally not known, but trampling of grassy slopes such as that reported for sheep develops in some cases. Bailey et al. (1933) speculated that nests of the snow goose _(Anser caerulescens)_ were destroyed by reindeer or their herdsmen in the Point Barrow area.
The destruction of vegetation by introduced rabbits and hares has been documented for many areas in the world. This destruction has often extended to seabirds. Perhaps the most dramatic example occurred on Laysan Island in the Hawaiian archipelago, where rabbits of unknown species were introduced in 1903. According to Warner (1963) it took less than 20 years for the rabbits to remove every green plant but three patches of _Sesuvium portulacastrum_. The Laysan duck _(Anas laysanensis)_ was brought perilously close to extinction. The rabbits were eliminated in the 1920's, and the population of ducks increased to over 600 by 1963, a figure thought to approximate the pre-disturbance population.
European hares _(Lepus europaeus)_ were introduced on Smith, San Juan, and Long islands, in Washington. On Smith Island, these burrowing animals apparently grazed nearly all the succulent vegetation close to the ground. By 1924, their burrows riddled the bluffs, causing them to cave into the ocean (Couch 1929). Couch found no seabirds nesting on the island, but found numerous tufted puffins _(Lunda cirrhata)_ present on the bluffs, but not nesting. A removal campaign was directed against the hares in 1924 and in a few years they were gone. Smith Island now supports nesting pelagic birds (D. Manuwal, personal communication).
Accounts of hare and rabbit introductions to islands are legion, but not all such introductions have drastically affected seabirds. Manana Island, Hawaii, is such a case. Tomich et al. (1968) believed that introduced rabbits _(Oryctolagus cuniculas)_ were not even indirectly detrimental to the nesting noddies _(Anous tolidus)_ and sooty terns _(Sterna fuscata)_. In some situations, introduced lagomorphs have been credited with benefiting seabirds. Lockley (1942) suggested that rabbits helped to open new breeding colonies of manx shearwaters _(Puffinus puffinus)_ at Skomer and in west Wales in general. In Alaska rabbits were introduced to Middleton Island in 1952 (Rausch 1958) and to Ananiuliak Island at an earlier unrecorded date. Both have developed sustaining populations in the presence of large seabird populations without measurable effect on the birds. On Ananiuliak glaucous-winged gulls _(Larus glaucescens)_ have been observed feeding on rabbits (W. S. Laughlin, personal communication).
Invertebrates have been introduced on three islands in the Aleutians. The black fly (_Simulium_ sp.) reached Adak by 1958, Shemya by 1964, and Amchitka in connection with activities of the Atomic Energy Commission in 1968. Apparently the insects were transported on jet aircraft. The pest appears well established on Adak, but its status on the other two islands is uncertain. Like the mosquito, the female black fly sucks blood from warm-blooded animals, and in the process becomes the vector of a _Leucocytozoan_ blood parasite of birds. In years of black fly abundance at Seney (Michigan) National Wildlife Refuge the blood parasite has been responsible for reproductive failure in Canada geese (_Branta canadensis_; Sherwood 1968). If black fly problems reach such a scale in the Aleutians, the parasites might prove limiting to pelagic birds as well as to waterfowl. Winds, for which the Aleutian region is famous, constitute a limiting factor for obligate blood-feeding Simuliids and may control the severity of this problem.
_Predatory Animals_
The list of introduced animals that prey on seabirds is extensive. Often several animals have been introduced to the same island. For example, in 1951 Amchitka Island in the Aleutians supported populations of feral dogs _(Canis familiaris)_ and cats _(Felis catus)_, rats _(Rattus norvegicus)_, and arctic fox. Their presence resulted from three of the usual sources of predator introductions: escape of pets, escape from visiting ships (and aircraft), and commercial introductions. Add introductions to control pests, such as that of the mongoose _(Herpestes auropunctatus)_ to the Hawaiian Islands, and only one source remains--the desire of man to improve on nature. In the Aleutians this impulse has taken the more innocuous form of fish and plant introductions, such as rainbow trout _(Salmo gairdneri)_ on Adak and Shemya, and trees (mostly Sitka spruce, _Picea sitkensis_) on every military base in the "Chain."
Rats appear to be the most commonly introduced predators on a worldwide scale. Ships furnish the traditional source of their introduction, but one of us (R.D.J.) has observed them disembarking from a military aircraft at Cold Bay on the Alaska Peninsula. These animals probably entered the plane at Adak, which received rats from military ships early in World War II.
Rats may be able to exploit a larger percentage of the seabird species on a given island than other introduced predators because they can enter crevices and burrows in search of the birds and their eggs and young. They also destroy ground-nesters, and cliff-nesters may not be altogether safe from them. Clayton M. White (personal communication) found that _Rattus norvegicus_ had ravaged every one of 16 eyries of the peregrine falcon _(Falco peregrinus)_ that he checked in 1971 at Amchitka Island, Alaska. Only one egg had tooth marks, however. Kenyon (1961) ascribed the disappearance of the song sparrow _(Melospiza melodia maxima)_ and the winter wren _(Troglodytes troglodytes kiskensis)_ from Amchitka to predation by rats.
Many authors have mentioned potential rat damage, but few have quantitatively documented it. Imber (1974), however, provided data concerning the magnitude of rat predation on diving petrels and storm-petrels on some New Zealand islands. He found that rats were taking between 10 and 35% of the chicks of gray-faced petrels _(Pterodroma macroptera gouldi)_ on Whale Island in the parts of the colonies where burrows were dense. On those parts of the island with a very low density of petrel burrows, rats were believed to have killed virtually every chick. Imber revealed that where Polynesian rats _(Rattus exulans)_ occur, diving petrels and storm-petrels are rare or absent, though they are widespread on neighboring islands. Imber concluded from his studies of the ecology of petrels and Polynesian and Norway rats that a petrel colony is endangered if invaded by a species of rat whose maximum weight approaches or exceeds the mean adult weight of the petrel. Harris (1970), who worked with dark-rumped petrels _(Pterodroma phacopygia)_ on Santa Cruz in the Galapagos Islands, indicated that black rats _(Rattus rattus)_ were responsible for the extremely low nesting success of the petrels there.
In British Columbia, Campbell (1968) recorded predation by the Alexandrian rat _(R. rattus)_ on ancient murrelets _(Synthliboramphus antiquus)_ at Langara Island. The extent of damage to the murrelet population is not known.
The animals most widely introduced in Alaska seabird habitat are the red fox _(Vulpes fulva)_ and the arctic fox. The red fox is native to the Alaska Peninsula and to the easternmost group of islands in the Aleutians, known as the Lissii or Fox Islands (Berkh 1823; Murie 1959). At the other end of the archipelago, in the group known as the Near Islands, Attu Island has a native population of the arctic fox (Tikhmenev 1861; Bancroft 1886). Between Umnak Island, the westernmost island of the Fox group, and Attu there are no native terrestrial mammals, and substantial avian populations evolved an ecology in the absence of mammalian predation (Murie 1959).
At the time of Russian contact with the Aleutians, both fox species were dominantly dark phase, and the early introductions (about 1836) by the Russian-American Company were of both species (Tikhmenev 1861). Initially both species were successful in developing insular populations, but in the long run the arctic fox proved the more successful. At Great Sitkin, Adak, and Kanaga, introduced red foxes maintained populations that were eliminated in the 1920's to be replaced by arctic foxes (unpublished records of the Aleutian Islands National Wildlife Refuge). Differential harvest of the preferred dark phase had in the meantime altered the genetic makeup of the population, and the light phase had become dominant. In the arctic fox populations, the dark phase remained generally dominant at about 95%, but in some small islands with limited genetic stock (e.g., the Semichis) the proportion approached one to one (unpublished records of the Aleutian Islands National Wildlife Refuge).
By 1936, the Aleutian archipelago constituted a large-scale fox farm, which in its 23 years of existence as a refuge had produced 25,641 fox pelts with a value of $1,162,826. During the same period, and perhaps earlier, arctic foxes were introduced on almost every island from the Aleutians to Prince William Sound, and on some of the islands in southeastern Alaska. The Aleutian Islands National Wildlife Refuge maintained records from which the above figures are quoted, but though records of other islands' use for fur farms exist in the archives of the Alaska Game Commission, no record of the fur values was kept.
Murie (1959) assessed the influence of the foxes by examining 2,501 fox droppings collected in 1936 and 1937 from 22 of the Aleutian Islands. He reported 57.8% of the food items in these droppings was avian--48.9% seabirds. The result of his investigations was the adoption of new policies governing issuance of permits for fox farming in the Refuge. The essential feature of these policies was the revocation of certain existing permits, with a view to reserving the islands concerned for wildlife use. The decision proved academic, for fur prices declined until no market for Aleutian arctic fox pelts could be found. But the foxes remained.
The most obvious damage has been the nearly complete extermination of the Aleutian Canada goose _(Branta canadensis leucopareia)_. It has vanished from its former nesting range in the Aleutian and Kuril Islands, except for Buldir Island in the western Aleutians (Jones 1963). Clark (1910) described this goose as extremely abundant on Agattu Island in 1909; however, foxes from Attu were introduced there in 1923, 1925, and 1929. Murie (1959) found "probably less than six pairs" in 4 days of traveling over the island in 1937.
In our main area of interest, cats appear to have been widely introduced, but we found no record of extensive predation on marine birds. Jehl (1972) attributed the extinction of the Guadalupe petrel to predation by cats, in combination with the destruction of vegetation by goats. Imber (1974) reported that "serious predation by cats upon a colony of gray-faced petrels on Little Barrier Island, New Zealand was observed in 1950. Since that time, the colony has become extinct."
Though feral dogs are reported present on islands in our area of interest, they do not appear to have significant influence on seabirds. On Attu Island, the pet dogs of personnel of the Coast Guard LORAN station are reported to take common eiders _(Somateria mollissima)_.
Conclusions
Ecological consequences of animal introductions to islands are rarely well documented. Usually no thought is devoted to such consequences until redress becomes difficult or quite impossible. Many of the introductions stem from a period before ecological understanding, and the introduced animal has acquired the status of a native. The arctic fox in the Aleutians fits all of these conditions. Until we conducted a thorough search of the literature, some of it difficult to secure and written in several languages, the original status of this animal was not known. Its elimination, now under way on selected islands, is difficult and expensive. Rapid recovery of some avian species, including certain passerines, has been observed. However, ecological homeostasis is the product of evolution, and restoration in the Aleutians must follow that course. It is not likely to proceed rapidly to a point thought desirable by man. The accidental introductions of animals such as rats and black flies in the Aleutians constitute
## particularly irksome events because they cannot be reversed. The new
ecology of Amchitka, from which the foxes have been removed, must evolve in the presence of these species. Its face will look very different than if they were not there. We would like to suggest a means by which such introductions may be prevented, but it seems likely that more, not less, can be expected.
Preventing the introduction of ungulates seems more likely to be successful, especially if the islands lie within a National Wildlife Refuge. Even this, however, becomes less certain with an expanding human population and, with it, demands for more land on which to produce food.
Legal restrictions have been suggested as a means to control or prevent introductions, but in the northern islands, little enforcement is likely. There is a phrase bearing on this, said to have governed human behavior in the early years of Caucasoid occupation of the Aleutian Islands, "Heaven is too high and the Czar too far away."
References
Bailey, A. M., C. D. Brower, and L. B. Bishop. 1933. Birds of the region of Point Barrow, Alaska. Prog. Act. Chic. Acad. Sci. 4(2):14-40.
Bancroft, H. H. 1886. History of Alaska, 1730-1885. San Francisco.
Berkh, V. 1823. The chronological history of the discovery of the Aleutian Islands or the exploits of the Russian merchants. N. Grech., St. Petersburg.
Campbell, R. W. 1968. Alexandrian rat predation on ancient murrelet eggs. Murrelet 49:38.
Carlquist, S. 1965. Island life: a natural history of the islands of the world. Natural History Press, New York.
Clark, A. H. 1910. The birds collected and observed during the cruises of the United States Fisheries Steamer "Albatross" in the North Pacific Ocean and in the Bering, Okhotsk, Japan, and Eastern seas from April to December 1906. Proc. U.S. Natl. Mus. 38:25-74.
Couch, L. K. 1929. Introduced European rabbits in the San Juan Islands, Washington. J. Mammal. 10:334-336.
Gabrielson, I. N., and F. C. Lincoln. 1959. The birds of Alaska. Stackpole Co. and Wildlife Management Institute, Washington, D.C.
Harris, M. P. 1970. The biology of an endangered species, the dark-rumped petrel (_Pterodroma phacopygia)_ in the Galapagos Islands. Condor 72:76-84.
Howell, T. R., and T. J. Cade. 1954. The birds of Guadalupe Island in 1953. Condor 56:283-291.
Imber, M. J. 1974. The rare and endangered species of the New Zealand region and the policies that exist for their management: petrels and predators. Paper presented to the International Council for Bird Preservation (XVI World Conference), Canberra.
Jehl, J. R. 1972. On the cold trail of an extinct petrel. Pac. Discovery 25:24-28.
Jones, R. D. 1963. Buldir Island, site of a remnant breeding population of Aleutian Canada geese. Wildfowl Trust Annu. Rep. 14:80-84.
Kenyon, K. W. 1961. Birds of Amchitka Island, Alaska. Auk 78(3):305-326.
Lockley, R. M. 1942. Shearwaters. Devin-Adair, New York.
MacArthur, R. H., and E. O. Wilson. 1967. The theory of island biogeography. Princeton Univ. Press, Princeton, N.J.
Murie, O. J. 1959. Fauna of the Aleutian Islands and Alaska Peninsula. U.S. Fish Wildl. Serv., N. Am. Fauna 61:1-364.
Norman, F. I. 1970. The effects of sheep on the breeding success and habitat of the short-tailed shearwater _(Puffinus tenuirostris)_ (Temminch). Aust. J. Zool. 18:215-242.
Odum, E. P. 1971. Fundamentals of ecology. W. B. Saunders Co., Philadelphia, Pa. 574 pp.
Rausch, R. 1958. The occurrence and distribution of birds on Middleton Island, Alaska. Condor 60(4):227-242.
Richardson, F. 1961. Breeding biology of the rhinoceros auklet on Protection Island. Condor 63(6):456-473.
Sherwood, G. A. 1968. Factors limiting production and expansion of local populations of Canada geese. Pages 73-85 _in_ R. L. Hine and C. Schoenfeld, eds. Canada goose management. Dembar Educational Research Service, Madison, Wis.
Tikhmenev, P. 1861. Historical review of the origin of the Russian-American Co. and its activity up to and the present time. Edward Weimar, St. Petersburg.
Tomich, P. Q., N. Wilson, and C. H. Lamoureux. 1968. Ecological factors on Manana Island, Hawaii. Pac. Sci. 12:352-368.
Warner, R. E. 1963. Recent history and ecology of the Laysan duck. Condor 65(1):2-23.
FOOTNOTES:
[66] Present address: Hawaiian Islands National Wildlife Refuge, Kilauea, Hawaii.
Oil Vulnerability Index for Marine Oriented Birds
by
James G. King
U.S. Fish and Wildlife Service P. O. Box 1287 Juneau, Alaska 99802
and
Gerald A. Sanger
U.S. Fish and Wildlife Service Anchorage, Alaska
Abstract
The 176 species of birds using marine habitats of the Northeast Pacific are graded on the basis of 20 factors that affect their survival. A score of 0, 1, 3, or 5, respectively, representing no, low, medium, or high significance is assigned for each factor. The total score is the Oil Vulnerability Index (OVI). The OVI's range from 1 to 100, an index of 100 indicating the greatest vulnerability. Using this system, one can rank the avifauna of different areas according to their vulnerability to environmental hazards as an aid in making management decisions.
Today's decision makers require an ever-increasing array of information and planning documents. The Federal Government's requirement for environmental impact statements under the National Environmental Protection Act of 1969 is but one example of this trend. These documents generally consider the effects of proposed actions on waterfowl and a few other species of birds, but the bulk of the avifauna is usually only listed, or sometimes ignored completely. A simple system for evaluating and presenting avian data is badly needed so that those interested in birds, whether technically trained or not, can easily grasp the implications of proposed actions. It is incumbent on biologists to devise new ways of presenting their knowledge so that it can be easily and effectively used by decision makers, who are often less informed. In short, biologists must do for the environmental impact statement assessors what Roger Tory Peterson did for the bird watchers by giving them a simple and comprehensible system.
The need for a system to evaluate relative vulnerabilities of bird populations is particularly great for birds that are being increasingly affected by marine oil pollution. The system needs to allow comparisons of potential impacts to birds resulting from various oil development projects in different locations and served by various modes of transport. The Oil Vulnerability Index (OVI) is our attempt to fulfill this informational need on the avifauna of the Northeast Pacific. Insofar as we know, this approach to assessing a wildlife management problem has been attempted only for ranking endangered species in a numeric ranking system that identified where restoration efforts could best be directed (Sparrowe and Wight 1975).
We are indebted to Gene Ruhr and Keith Schreiner for ideas generated in their work with endangered species. Frank Pitelka, James Bartonek, Kent Wohl, and Mary Lou King reviewed portions of the manuscript and offered helpful suggestions. Jack Hodges helped prepare the OVI tables.
Methods
A list of 176 species of birds using marine habitats in or near the States of Washington and Alaska and the Province of British Columbia (Table 1, left column) was compiled from checklists by the American Ornithologists' Union (AOU 1957) and Gibson (1970). Nomenclature is from AOU (1957). The scientific names of three species of shorebirds recently identified in the Aleutian Islands that were not listed by the AOU (1957) came from Peterson et al. (1967).
Each bird was scored on 20 factors that affect its survival (Table 1). Point scores for most birds were either 0, 1, 3, or 5, indicating no, low, medium, or high importance, respectively, in their biology or habits as related to Northeast Pacific oil development. Rare or accidental species were given only one point for occurrence, and endangered species 99 points for population size plus 1 point for occurrence. Thus the potential range of the OVI's is from 1 to 100.
The factors in Table are largely self-explanatory. The items under "range" apply to the entire world population of the species. "Productivity" is derived from a combination of clutch size and age at first nesting. Specialization is used in the biological sense to compare a versatile species like mallards (_Anas platyrhynchos)_ with a less versatile species such as the trumpeter swan _(Olor buccinator)_. Mortality under "history of oiling" is based on our knowledge that some species (e.g., alcids) have been more involved than others such as gulls. Exposure relates to the level of exposure within the Pacific area in any season.
Information on many of the factors for many species is scanty at best, and subjective appraisals were made by us when information was lacking. Opinions as to appropriate scores will vary among experts. References used, in part, in preparing Table 1 were: AOU 1957; Fay and Cade 1959; Gabrielson and Lincoln 1959; Isleib and Kessel 1973; Kortright 1942; Murie 1959; Palmer 1962; Robbins et al. 1966; Sanger 1972; and Stout et al. 1967.
Results
The OVI for each of 176 bird species is listed in Table 1. The average OVI for 22 avian families comprising 128 species that are neither rare stragglers nor endangered ranged from 19 to 88, with a mean of 51 (Table 3).
Tables 4 and 5 show a possible use for the OVI by comparing impacts in two large, widely separated areas. A species list from Southeast Alaska (U.S. Forest Service and Alaska Department of Fish and Game 1970) is compared with a list from the Aleutian Islands (U.S. Fish and Wildlife Service 1974). Only commonly occurring species are included. These tables graphically display rather strong differences in the vulnerability of the avifauna of each area. A person explaining comparative impacts of projects might use the tables in the following way:
• Column 1, with scores from 1 to 20 points, indicates birds with a low level of project involvement, where damage or future costs would not be expected. As this will normally be the longest list, as in Tables 4 and 5, one would expect an immediate rise of interest on the part of the planning agency, which is probably eager to learn where problems will be fewest.
• Column 2 (21 to 40 points) indicates birds for which there is a low level of concern. Perhaps all that is needed is a review to determine if special characteristics of the project might be detrimental to these species.
• Column 3 (41 to 60 points) might be called "trial and error" species. If some birds are adversely affected, it will not be catastrophic. As the project develops it will be merely necessary to monitor these to make sure their status is not adversely affected. If it is, there will be time to develop conservation measures.
• Columns 4 and 5 (61 to 80 points and 81 to 100 points, respectively) include the species where concern is high. It is for these species that research money will be needed, where project modifications may be required, where a contingency plan in case of disaster is needed, where a conservation technology will be needed, and where periodic project shutdown could be called for.
Table 1. _Oil Vulnerability Index (OVI) for waterbirds in the Northeast Pacific Region._
Range |Breeding range size | |Migration length | | |Winter range size | | | |Marine orientation | | | | | | | | Population | | | | |Population size | | | | | |Productivity | | | | | | | | | | | | Habits | | | | | | |Roosting | | | | | | | |Foraging | | | | | | | | |Escape | | | | | | | | | |Flocking on water | | | | | | | | | | |Nesting density | | | | | | | | | | | |Specialization | | | | | | | | | | | | | | | | | | | | | | | | Mortality | | | | | | | | | | | | |Hunted by man | | | | | | | | | | | | | |Animal depredations | | | | | | | | | | | | | | |Non-oil pollution | | | | | | | | | | | | | | | |History of | | | | | | | | | | | | | | | | oiling | | | | | | | | | | | | | | | | |Annual | | | | | | | | | | | | | | | | | exposure | | | | | | | | | | | | | | | | |Spring | | | | | | | | | | | | | | | | | |Summer | | | | | | | | | | | | | | | | | | |Fall | | | | | | | | | | | | | | | | | | | |Winter | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |OVI Family, common (AOU) name and | | | | | | | | | | | | | | | | | | | | |Total scientific name | | | | | | | | | | | | | | | | | | | | |Points ------------------------------------------------------------------------------- Gaviidae Common loon _(Gavia immer)_ 1 3 3 3 1 5 5 5 5 1 1 3 1 1 3 3 1 0 1 1 47 Yellow-billed loon _(G. adamsii)_ 3 3 5 3 5 5 5 5 5 1 1 3 1 1 0 3 5 1 5 5 65 Arctic loon _(G. arctica)_ 3 3 3 3 3 5 5 5 5 1 1 3 1 1 3 3 3 1 3 3 58 Red-throated loon _(G. stellata)_ 1 3 3 5 1 5 5 5 5 1 1 3 1 1 3 3 1 0 1 1 49 Podicipedidae Red-necked grebe (_Podiceps_ _grisegena_) 1 3 3 3 1 3 5 5 5 1 1 3 0 1 3 3 1 0 1 1 44 Horned grebe _(P. auritus)_ 1 3 3 3 1 3 5 5 5 3 1 3 0 3 3 3 1 0 1 1 48 Western grebe (_Aechmophorus_ _occidentalis_) 3 3 3 5 1 3 5 5 5 5 1 3 0 1 3 5 1 0 1 3 56 Diomedeidae Short-tailed albatross _(Diomedea albatrus)_ 99 1 100 Black-footed albatross _(D. nigripes)_ 5 1 1 5 3 5 5 3 3 1 5 5 0 0 1 3 1 1 1 1 50 Laysan albatross _(D. immutabilis)_ 5 1 1 5 3 5 5 3 3 1 5 5 0 0 1 3 1 1 1 3 52 Procellaridae Fulmar _(Fulmarus glacialis)_ 3 3 1 5 1 5 5 3 3 3 5 3 0 1 1 3 3 3 3 3 57 Pink-footed shearwater _(Puffinus creatopus)_ 3 1 1 5 1 5 5 3 3 3 5 3 0 1 1 3 1 1 1 1 47 Pale-footed shearwater _(P. carneipes)_ 1 1 New Zealand shearwater _(P. bulleri)_ 1 1 Sooty shearwater _(P. griseus)_ 1 1 1 5 1 5 5 3 3 5 5 3 1 1 1 3 1 5 1 0 51 Slender-billed shearwater _(P. tenuirostris)_ 1 1 3 5 1 5 5 3 3 5 5 3 1 1 1 3 1 5 1 0 53 Scaled petrel (_Pterodroma_ _inexpectata_) 1 1 Cooks petrel _(P. cookii)_ 1 1 Hydrobatidae Fork-tailed storm-petrel _(Oceanodroma furcata)_ 3 3 3 5 1 5 5 3 3 3 5 3 0 1 1 3 5 5 5 5 67 Leach's storm-petrel _(O. leucorhoa)_ 1 3 1 5 1 5 5 3 3 3 5 3 0 1 1 3 5 5 5 5 63 Pelecanidae Brown pelican _(Pelecanus occidentalis)_ 1 1 Phalacrocoracidae Double-crested cormorant _(Phalacrocorax auritus)_ 1 3 3 3 3 3 1 5 3 1 3 3 0 1 3 5 3 3 5 52 Brandt's cormorant _(P. penicillatus)_ 3 3 3 5 3 3 1 5 3 1 3 3 0 1 3 5 3 3 3 3 57 Pelagic cormorant _(P. pelagicus)_ 3 3 3 5 3 3 1 5 3 3 3 3 0 1 3 5 5 1 5 5 63 Red-faced cormorant _(P. urile)_ 5 3 3 5 3 3 1 5 3 3 3 3 0 1 1 5 5 5 3 3 63 Ardeidae Great blue heron _(Ardea herodias)_ 1 3 1 1 3 3 1 1 1 1 3 3 0 1 1 1 1 1 1 1 29 Anatidae Whooper swan _(Olor cygnus)_ 1 1 Whistling swan _(O. columbianus)_ 3 3 3 3 3 3 5 3 1 5 1 3 3 1 3 1 3 0 3 0 50 Trumpeter swan _(O. buccinator)_ 5 5 3 3 5 3 5 5 1 5 1 5 1 1 3 3 3 0 3 3 63 Canada goose _(Branta canadensis)_ 1 3 1 1 5 3 1 1 1 3 1 1 5 1 1 1 1 1 1 1 34 Black Brant _(B. nigricans)_ 3 3 3 5 3 3 5 5 3 5 3 3 5 1 3 5 3 1 5 3 70 Emperor goose _(Philacte canagica)_ 3 5 5 5 3 3 3 3 3 3 3 3 3 1 1 5 5 3 5 5 70 White-fronted goose _(Anser albifrons)_ 3 3 3 1 3 3 1 1 1 1 1 1 5 1 3 1 1 1 1 1 36 Snow goose _(Chen hyperborea)_ 1 3 1 1 3 3 1 1 1 1 1 1 5 1 3 1 1 1 1 1 32 Mallard _(Anas platyrhynchos)_ 1 3 1 1 1 1 1 3 3 3 1 1 5 3 3 1 1 1 1 1 36 Gadwall _(A. strepera)_ 3 3 1 1 1 1 1 3 3 3 1 1 5 3 3 1 1 1 1 1 38 Pintail _(A. acuta)_ 1 3 1 1 1 1 1 3 3 3 1 1 5 3 3 1 1 1 1 1 36 Common teal _(A. crecca)_ 1 1 Green-winged teal _(A. carolinensis)_ 1 3 1 1 1 1 1 3 3 1 1 1 5 3 3 1 1 1 1 1 34 Blue-winged teal _(A. discors)_ 1 1 Cinnamon teal _(A. cyanoptera)_ 1 1 European wigeon _(Mareca penelope)_ 1 1 American wigeon _(M. americana)_ 1 3 1 1 1 1 1 3 3 3 1 1 5 3 3 1 1 1 1 1 36 Shoveler _(Spatula clypeata)_ 1 3 1 1 1 1 1 3 3 1 1 1 5 3 3 1 1 1 1 1 34 Redhead _(Aythya americana)_ 1 3 1 1 5 3 5 5 5 3 1 3 5 1 3 3 1 1 1 1 52 Ring-necked duck _(A. collaris)_ 1 1 Canvasback _(A. valisineria)_ 1 3 1 1 5 3 5 5 5 3 1 3 5 1 3 3 1 1 1 1 52 Greater scaup _(A. marila)_ 1 3 1 5 1 3 5 5 5 3 1 3 5 1 3 3 1 1 1 1 52 Lesser scaup _(A. affinis)_ 1 3 1 3 1 3 5 5 5 3 1 3 5 1 3 3 1 1 1 1 50 Common goldeneye _(Bucephala clangula)_ 1 3 1 3 1 3 5 5 5 3 1 3 3 1 3 3 1 1 1 1 48 Barrow's goldeneye _(B. islandica)_ 3 3 1 3 1 3 5 5 5 3 1 3 3 1 3 3 3 1 3 3 56 Bufflehead _(B. albeola)_ 1 3 1 3 1 3 5 5 5 3 1 3 1 1 3 3 3 1 3 3 52 Oldsquaw _(Clangula hyemalis)_ 1 3 1 5 1 3 5 5 5 5 1 3 3 1 1 5 5 3 5 5 66 Harlequin duck _(Histrionicus histrionicus)_ 3 5 1 5 1 3 1 3 3 3 1 3 1 1 1 5 5 5 5 5 60 Steller's eider _(Polysticta stelleri)_ 3 3 5 5 1 3 5 5 5 5 1 3 3 1 1 5 5 3 5 5 72 Common eider _(Somateria mollissima)_ 3 5 3 5 1 3 5 5 5 3 1 3 1 1 1 5 5 3 5 5 68 King eider _(S. spectabilis)_ 3 5 3 5 1 3 5 5 5 5 1 3 1 1 1 5 5 3 5 5 70 Spectacled eider _(Lampronetta fisheri)_ 5 5 5 5 3 3 5 5 5 5 3 3 1 1 1 5 5 3 5 5 78 White-winged scoter _(Melanitta deglandi)_ 3 3 3 3 1 3 5 5 5 5 1 3 3 1 3 5 5 5 5 5 72 Surf scoter _(M. perspicillata)_ 3 3 3 3 1 3 5 5 5 5 1 3 3 1 3 5 5 5 5 5 72 Common scoter _(Oidemia nigra)_ 3 3 3 3 1 3 5 5 5 5 1 3 3 1 3 5 5 5 5 5 72 Ruddy duck _(Oxyura jamaicensis)_ 1 3 1 3 1 1 5 5 5 5 1 5 5 3 3 3 1 0 1 3 55 Hooded merganser _(Laphodytes cucullatus)_ 1 3 1 1 3 3 3 5 3 1 1 3 1 1 3 1 1 0 1 1 37 Common merganser _(Mergus merganser)_ 1 3 3 3 1 3 3 5 5 3 1 3 3 1 3 3 3 3 3 3 56 Red-breasted merganser _(M. serrator)_ 1 3 3 3 1 3 3 5 5 3 1 3 3 1 3 3 3 3 3 3 56 Accipitridae Bald eagle _(Haliaeetus leucocephalus)_ 1 5 3 3 5 5 0 1 1 0 1 5 0 0 5 3 5 5 5 5 58 Steller's sea eagle _(H. pelagicus)_ 1 1 Marsh hawk _(Circus cyaneus)_ 1 3 1 1 1 3 1 1 1 0 1 1 0 0 1 1 1 0 1 0 19 Pandionidae Osprey _(Pandion haliaetus)_ 1 3 1 1 5 5 0 1 1 0 1 5 3 1 5 1 1 1 1 0 37 Falconidae Peregrine falcon _(Falco peregrinus)_ 1 3 1 1 5 5 0 1 1 0 1 3 3 0 5 1 3 3 3 1 41 Gruidae Sandhill crane _(Grus canadensis)_ 1 3 1 1 1 3 1 1 1 0 1 1 3 1 1 1 1 1 1 0 24 Rallidae American coot _(Fulica americana)_ 1 3 1 1 1 1 3 3 1 3 1 1 3 3 3 1 1 0 1 1 33 Haematopodidae Black oystercatcher _(Haematopus bachmani)_ 5 5 5 5 3 5 1 1 1 1 1 5 0 1 3 3 5 5 5 5 65 Charadriidae Ringed plover _(Charadrius hiaticula)_ 1 1 Semipalmated plover _(C. semipalmatus)_ 1 1 1 1 1 3 1 1 1 1 1 1 0 5 1 1 3 1 3 0 28 Mongolian plover _(C. mongolus)_ 1 1 Killdeer _(C. vociferus)_ 1 3 1 1 1 3 1 1 1 1 1 1 0 5 1 1 1 1 1 0 26 Dotterel _(Eudromias morinellus)_ 1 1 American golden plover _(Pluvialis dominica)_ 1 1 1 3 3 3 3 1 1 3 1 3 3 5 0 1 1 0 1 0 35 Black-bellied plover _(Squatarola squatarola)_ 1 1 1 5 3 3 1 1 1 3 1 3 3 5 1 3 3 1 3 0 43 Surfbird _(Aphriza virgata)_ 5 1 5 5 3 3 1 1 1 3 1 3 0 5 1 3 5 0 5 3 54 Ruddy turnstone _(Arenaria interpres)_ 1 1 3 5 3 3 1 1 1 3 1 3 0 5 1 3 3 3 3 0 44 Black turnstone _(A. melanocephala)_ 5 3 3 5 3 3 1 1 1 3 1 3 0 5 1 3 5 3 5 3 57 Scolopacidae Common snipe _(Capella gallinago)_ 1 1 1 1 1 3 1 1 1 1 1 1 5 5 1 1 1 1 1 0 29 Eurasian curlew _(Numenius arquata)_ 1 1 Whimbrel _(N. phaeopus)_ 1 1 1 3 3 3 1 1 1 3 1 3 1 3 1 3 3 1 3 0 37 Bristle-thighed curlew _(N. tahitiensis)_ 5 1 1 5 5 3 3 1 1 3 1 1 1 3 1 3 3 1 3 0 45 Eskimo curlew _(N. borealis)_ 99 1 100 Upland plover _(Bartramia longicauda)_ 1 1 1 0 5 3 1 1 1 0 1 1 3 3 1 0 1 1 1 0 26 Spotted sandpiper _(Actitis macularia)_ 1 3 1 1 1 3 1 1 1 1 1 1 0 3 1 1 1 1 1 0 24 Common sandpiper _(Tringa hypoleucos)_ 1 1 Solitary sandpiper _(T. solitaria)_ 1 1 Wood sandpiper _(T. glareola)_ 1 1 Wandering tattler _(Heteroscelus incanum)_ 5 1 1 5 5 3 1 1 1 3 1 3 1 3 1 3 5 0 5 0 48 Polynesian tattler _(H. brevipes)_ 1 1 Willet _(Catoptrophorus semipalmatus)_ 1 1 Greater yellowlegs _(Totanus melanoleucus)_ 1 5 1 1 3 3 1 1 1 1 1 1 3 3 1 1 1 0 1 0 30 Lesser yellowlegs _(T. flavipes)_ 1 5 1 1 3 3 1 1 1 1 1 1 3 3 1 1 1 0 1 0 30 Spotted redshank _(T. totanus)_ 1 1 Greenshank _(Tringa nebularia)_ 1 1 Knot _(Calidris canutus)_ 1 1 1 5 5 3 1 1 1 3 1 1 1 3 1 3 3 3 1 0 39 Great knot _(C. tenuirostris)_ 1 1 Rock sandpiper _(Erolia ptilocnemis)_ 5 3 3 5 3 3 1 1 1 3 1 3 0 3 1 3 5 5 5 5 59 Sharp-tailed sandpiper _(E. acuminata)_ 3 1 3 5 3 3 1 1 1 3 1 3 0 3 3 3 3 0 3 3 46 Pectoral sandpiper _(E. melanotos)_ 1 1 3 1 3 3 1 1 1 1 1 1 0 3 1 1 3 3 3 0 32 White-rumped sandpiper _(E. fuscicollis)_ 1 1 Baird sandpiper _(E. bairdii)_ 1 3 3 1 3 3 1 1 1 1 1 1 0 3 1 1 3 3 3 0 34 Least sandpiper _(E. minutilla)_ 1 3 3 3 1 3 1 1 1 1 1 1 0 3 1 1 3 3 3 0 34 Long-toed stint _(E. subminuta)_ 1 1 Temminck's stint _(Calidrus temminckii)_ 1 1 Rufous-necked sandpiper _(E. ruficollis)_ 3 1 3 5 3 3 1 1 1 3 1 1 0 3 1 3 1 1 1 0 36 Curlew sandpiper _(E. ferruginea)_ 1 1 Dunlin _(E. alpina)_ 1 3 1 5 1 3 1 1 1 1 1 1 0 3 3 3 3 3 3 3 41 Short-billed dowitcher _(Limnodromus griseus)_ 3 3 3 3 3 3 1 1 1 1 1 3 3 3 1 3 3 3 3 0 45 Long-billed dowitcher _(L. scolopaceus)_ 5 3 3 3 3 3 1 1 1 1 1 3 3 3 1 3 3 3 3 0 47 Stilt sandpiper _(Micropalama himantopus)_ 1 1 Semipalmated sandpiper _(Ereunetes pusillus)_ 1 3 1 3 1 3 1 1 1 1 1 1 0 3 1 1 3 5 3 0 34 Western sandpiper _(E. mauri)_ 5 3 3 5 1 3 1 1 1 1 1 1 0 3 3 3 3 5 3 1 47 Buff-breasted sandpiper _(Tryngites subruficollis)_ 1 1 Marbled godwit _(Limosa fedoa)_ 1 1 Bar-tailed godwit _(L. lapponica)_ 3 1 1 5 3 3 1 1 1 3 1 3 3 3 1 3 5 5 3 0 49 Hudsonian godwit _(L. haemastica)_ 1 1 Black-tailed godwit _(L. limosa)_ 1 1 Ruff _(Philomachus pugnax)_ 1 1 Sanderling _(Crocethia alba)_ 3 1 1 5 3 3 1 1 1 3 1 3 0 3 1 3 3 3 3 3 45 Spoon-billed sandpiper _(Eurynorhynchus pygmeum)_ 1 1 Phalaropodidae Red phalarope _(Phalaropus fulicarius)_ 3 1 1 5 1 3 5 5 1 5 1 5 0 3 1 5 5 3 5 0 58 Wilson's phalarope _(Steganopus tricolor)_ 1 1 Northern phalarope _(Lobipes lobatus)_ 3 1 3 5 1 3 5 5 1 5 1 5 0 3 3 5 5 3 5 0 62 Stercorariidae Pomarine jaeger _(Stercorarius pomarinus)_ 1 1 1 5 1 3 3 3 1 3 1 3 1 1 1 3 3 3 3 0 41 Parasitic jaeger _(S. parasiticus)_ 1 1 1 5 1 3 3 3 1 3 1 3 1 1 3 3 3 3 3 0 43 Long-tailed jaeger _(S. longicaudus)_ 1 1 1 3 1 3 3 3 1 3 1 3 1 1 1 3 3 3 3 0 39 Skua _(Catharacta skua)_ 1 1 Laridae Glaucous gull _(Larus hyperboreus)_ 1 5 3 3 1 3 3 3 1 3 3 1 0 1 1 1 3 3 3 3 45 Glaucous-winged gull _(L. glaucescens)_ 5 1 3 5 1 3 3 3 1 3 5 1 1 1 1 1 5 5 5 3 56 Slaty-backed gull _(L. schistisagus)_ 1 1 Western gull _(L. occidentalis)_ 3 1 3 5 1 3 3 3 1 3 5 1 1 1 1 1 3 3 3 3 48 Herring gull _(L. argentatus)_ 1 3 1 3 1 3 1 3 1 3 1 1 1 1 1 1 3 3 3 3 38 Thayer's gull _(L. thayeri)_ 3 3 5 3 1 3 1 3 1 3 1 1 1 1 1 1 3 1 3 3 42 California gull _(L. californicus)_ 3 5 3 3 1 3 3 3 1 3 1 1 1 1 1 1 1 1 1 1 38 Ring-billed gull _(L. delawarensis)_ 1 5 3 3 1 3 3 3 1 3 1 1 1 1 1 1 1 1 1 1 36 Mew gull _(L. canus)_ 1 5 3 3 1 3 3 3 1 3 1 1 1 1 1 1 3 3 3 3 44 Black-headed gull _(L. ridibundus)_ 1 1 Franklin's gull _(L. pipixcan)_ 1 1 Bonaparte's gull _(L. philadelphia)_ 1 5 3 3 1 3 3 3 1 3 1 1 1 1 1 1 3 1 3 1 40 Heerman's gull _(L. 1 1 heermanni)_ Ivory gull _(Pagophila 1 5 3 5 3 3 3 3 1 3 1 3 0 1 1 1 1 1 1 3 43 eburnea)_ Black-legged kittiwake 1 3 3 5 1 3 3 3 1 3 5 3 0 1 1 1 3 3 3 3 49 _(Rissa tridactyla)_ Red-legged kittiwake _(R. 5 5 5 5 3 3 3 3 1 3 5 3 0 1 0 1 5 5 5 5 66 brevirostris)_ Ross' gull _(Rhodostethia 5 5 3 5 3 3 3 3 1 3 5 5 0 1 0 1 3 1 3 3 56 rosea)_ Sabine's gull _(Xema sabini)_ 3 3 3 5 1 3 3 3 1 3 1 3 0 1 1 1 3 3 3 0 44 Common tern _(Sterna 1 1 hirundo)_ Arctic tern _(S. paradisaea)_ 1 1 1 3 1 3 3 3 1 3 1 1 0 1 1 1 3 1 3 0 32 Aleutian tern _(S. aleutica)_ 5 3 3 5 3 3 3 3 1 3 1 1 0 1 1 1 5 5 5 1 53 Caspian tern _(Hydroprogne 1 1 caspia)_ Black tern _(Chlidonias 1 1 niger)_ Alcidae Common murre _(Uria aalge)_ 1 5 3 5 1 5 5 5 5 5 5 3 1 1 3 5 3 3 3 3 70 Thick-billed murre _(U. 1 5 3 5 1 5 5 5 5 5 5 3 1 1 3 5 3 3 3 3 70 lomvia)_ Dovekie _(Plautus alle)_ 1 1 Black guillemot _(Cepphus 1 5 3 5 3 5 5 5 5 3 5 5 1 1 1 5 3 3 3 3 70 grylle)_ Pigeon guillemot _(C. 5 5 3 5 3 5 5 5 5 3 5 5 1 1 3 5 5 5 5 3 82 columba)_ Marbled murrelet 5 5 3 5 1 5 5 5 5 3 5 5 1 3 3 5 5 5 5 5 84 _(Brachyramphus marmoratus)_ Kittlitz's murrelet _(B. 5 5 5 5 1 5 5 5 5 5 5 5 1 3 3 5 5 5 5 5 88 brevirostris)_ Xantus' murrelet 1 1 _(Endomychura hypoleuca)_ Ancient murrelet 3 3 3 5 1 5 5 5 5 5 5 5 1 3 3 5 3 3 3 3 74 _(Synthliboramphus antiquus)_ Cassin's auklet 5 3 5 5 1 5 5 5 5 5 5 5 1 3 3 5 5 5 5 3 84 _(Ptychoramphus aleutica)_ Parakeet auklet 3 3 3 5 1 5 5 5 5 5 5 5 1 3 3 5 5 5 5 3 80 _(Cyclorrhynchus psittacula)_ Crested auklet _(Aethia 3 3 3 5 1 5 5 5 5 5 5 5 1 3 1 5 5 3 5 3 76 cristatella)_ Least auklet _(A. pusilla)_ 3 3 3 5 1 5 5 5 5 5 5 5 1 3 3 5 5 5 5 3 80 Whiskered auklet _(A. 5 5 5 5 1 5 5 5 5 5 5 5 1 3 3 5 5 5 5 5 88 pygmaea)_ Rhinoceros auklet 3 3 3 5 1 5 5 5 5 5 5 5 1 3 3 5 3 3 3 3 74 _(Cerorhinca monocerata)_ Horned puffin _(Fratercula 3 5 3 5 1 5 5 5 5 3 5 5 1 3 1 5 3 3 3 3 72 corniculata)_ Tufted puffin _(Lunda 3 5 3 5 1 5 5 5 5 3 5 5 1 3 1 5 3 3 3 3 72 cirrhata)_ Alcedinidae Belted kingfisher 1 1 3 1 1 1 1 5 1 0 1 3 0 3 1 1 1 1 1 1 28 _(Megaceryle alcyon)_ Corvidae Common raven _(Corvus corax)_ 1 1 1 1 1 1 1 1 1 0 1 1 3 1 1 1 1 1 1 1 21 Northwestern crow _(C. 3 5 3 3 1 1 1 1 1 0 1 3 1 1 1 1 5 5 5 5 47 caurinus)_
Table 2. _Criteria and points used in calculating Oil Vulnerability Index._
Point assignment 1 3 5 Range Breeding Large Medium Small Migration Long Medium Short Winter Large Medium Small Marine orientation Coastal zone Intertidal Open water
Population Size Large Medium Small Productivity Large Medium Small
Habits Roosting Shore Drift Water Foraging Walking Flying Swimming Escape Leave area Fly Dive Flocking Small Medium Large Nesting density Low Medium High Specialization Low Medium High
Mortality Hunted by man Low Medium High Animal depredations Low Medium High Non-oil pollution Low Medium High History of oiling Low Medium High
Exposure Spring Low Medium High Summer Low Medium High Fall Low Medium High Winter Low Medium High
With these points in mind it is immediately obvious that Southeast Alaska (Table 4), which has only 9 high-score birds, offers far less potential for bird problems than does the Aleutian area (Table 5), which has 24 high-score species. The planning agency could make some immediate decisions on site priorities and research funding based on such information.
Discussion
We are convinced that the OVI principle expressed here will become a useful management tool with all sorts of possible applications. We recognize some difficulties with the present version, but believe it is timely to present the system so that a broader range of thought, improvements, and application can be applied to it.
Of prime importance is the system's simplicity. The use of four levels of value for each factor, instead of five or more, is an attempt to simplify. Ian McHarg (1969) has shown that extremely complex land-use values can be graphically compared and displayed by using three levels in a way that is useful to decision makers. The difficulty of using more levels of value was indicated by Sparrowe and Wight (1975) who used up to 10 levels, enormously complicating the problem of dealing with low-quality information, which is often all that is available. The use of scores of 0, 1, 3, 5 instead of 0, 1, 2, 3 for 20 factors enabled us to use the convenient 100 points instead of 60 points as the maximum potential total score for any species.
The 20 factors that were evaluated are admittedly arbitrary; with refinement and more detailed data they could be adjusted to show better separation between affected species. The decision to use 20 factors instead of more or less again relates to simplicity. This appears to be the minimum number that will assure species separation and that can be neatly displayed.
Table 3. _Oil Vulnerability Index (OVI) for families of birds of the Northeast Pacific marine habitats, excluding rare and endangered species in the scoring._
OVI per species Number of Total Family species OVI Average Range
Loons--Gaviidae 4 219 55 47-65 Grebes--Podicipedidae 3 148 49 44-56 Albatrosses--Diomedeidae 2 102 51 50-52 Shearwaters--Procellaridae 4 208 52 47-57 Storm-petrels--Hydrobatidae 2 130 65 63-67 Cormorants--Phalacrocoracid 4 235 59 52-63 Herons--Ardeidae 1 29 29 29 Waterfowl--Anatidae 33 1,765 53 32-78 Eagles and Hawks--Accipitridae 2 77 39 19-58 Ospreys--Pandionidae 1 37 37 37 Falcons--Falconidae 1 41 41 41 Cranes--Gruidae 1 24 24 24 Rails and Coots--Rallidae 1 33 33 33 Oystercatchers--Haematopodidae 1 65 65 65 Plovers--Charadriidae 7 287 41 26-57 Sandpipers--Scolopacidae 22 857 39 24-59 Phalaropes--Phalaropodidae 2 120 60 58-62 Jaegers and Skuas--Stercorariidae 3 123 41 39-43 Gulls and Terns--Laridae 16 730 46 32-66 Auks--Alcidae 15 1,164 78 70-88 Kingfishers--Alcedinidae 1 28 28 28 Crows--Corvidae 2 68 34 21-47 Total and Mean 128 6,490 51 19-88
The system will be much more useful when it is expanded to the subspecific level. Many Holarctic species are represented in the Northeast Pacific by a single race that would have a much higher OVI than the species as a whole. For example, the OVI for the Peale's peregrine falcon _(Falco peregrinus pealei)_ confined to marine habitats within the Pacific region would be high; and the endangered Aleutian Canada goose _(Branta canadensis leucopareia)_ would score 100 points instead of the 34 we show for Canada geese _(B. c.)_. If Tables 4 and 5 showed subspecies, the differences in value would be more marked.
Tables 4 and 5 are for broad geographical areas. A comparison between smaller areas would probably show more dramatic differences.
Because the dearth of easily available, applicable information poses a problem in evaluating the various factors, our scoring was conservative. Experts on the various avian families can doubtless refine the scoring. If this system proves useful, investigators will begin to acquire the information needed for more precise evaluations. Ultimate perfection may never be achieved; however, as with the field guides, the fact of minor professional disagreement should not destroy the system's utility.
We believe re-scoring of all birds on the basis of various projects should be avoided because a standard against which individual projects can be measured is needed. If everyone did their own scoring, there would be no standard, and projects evaluated by different investigators would not be comparable. If a species list for the project area and standard point scores are used, the level of involvement for many species and perhaps for most species will be properly identified. As with any system, there will be exceptions and the assessor will need to deal with these as appropriate. The result will still be to focus attention on those species and impacting factors where it is most needed.
Table 4. _Oil Vulnerability Index for 109 species of birds of Southeast Alaska (Total Points--2,678)._
OVI 1-20 OVI 21-40 OVI 41-60 Marsh hawk 19 Great blue heron 29 Common loon 47 52 species, rare Canada goose 34 Arctic loon 58 or occasional (one point each) 52 White-fronted goose 36 Red-throated loon 49 Snow goose 32 Red-necked grebe 44 Mallard 36 Horned grebe 48 Pintail 36 Whistling swan 50 Green-winged teal 34 Trumpeter swan 63 American wigeon 36 Greater scaup 52 Semipalmated plover 28 Lesser scaup 52 Killdeer 26 Common goldeneye 48 Common snipe 29 Barrow's goldeneye 56 Spotted sandpiper 24 Bufflehead 52 Greater yellowlegs 30 Harlequin duck 60 Lesser yellowlegs 30 Common merganser 56 Pectoral sandpiper 32 Red-breasted merganser 56 Least sandpiper 34 Bald eagle 58 Herring gull 38 Peregrine falcon 41 Bonaparte's gull 40 Black turnstone 57 Arctic tern 32 Rock sandpiper 59 Belted kingfisher 28 Dunlin 41 Common raven 21 Short-billed dowitcher 41 Western sandpiper 47 Glaucous-winged gull 56 Thayer's gull 42 Mew gull 44 Northwestern crow 47 Totals 71 665 1,324
OVI 61-80 OVI 81-100
Pelagic cormorant 63 Pigeon guillemot 82 Oldsquaw 66 Marbled murrelet 84 White-winged scoter 72 Surf scoter 72 Black oystercatcher 65 Northern phalarope 62 Common murre 70
Totals 470
Table 5. _Oil Vulnerability Index for 123 species of birds of the Aleutian Islands_ (Total Points--2,689).
OVI 1-20 OVI 21-40 OVI 41-60 80 species, rare Canada goose 34 Fulmar 57 or occasional Least sandpiper 34 Slender-billed shearwater 53 (one point each) 80 Arctic tern 32 Greater scaup 52 Common raven 21 Common goldeneye 48 Bufflehead 52 Harlequin duck 60 Bald eagle 58 Peregrine falcon 41 Ruddy turnstone 44 Rock sandpiper 59 Western sandpiper 47 Red phalarope 58 Parasitic jaeger 43 Glaucous-winged gull 56 Black-legged kittiwake 49
Totals 80 121 777
OVI 61-80 OVI 81-100
Fork-tailed storm-petrel 67 Pigeon guillemot 82 Leach's storm-petrel 63 Whiskered auklet 88 Pelagic cormorant 63 Red-faced cormorant 63 Black Brant 70 Emperor goose 70 Oldsquaw 66 Steller's eider 72 Common eider 68 King eider 70 White-winged scoter 72 Common scoter 72 Black oystercatcher 65 Red-legged kittiwake 66 Common murre 70 Thick-billed murre 70 Ancient murrelet 74 Parakeet auklet 80 Crested auklet 76 Least auklet 80 Horned puffin 72 Tufted puffin 72 Totals 1,541 170
We have used our OVI system to show the vulnerability of birds to oil, but it seems likely that the vulnerability index could be applied on a much broader scale to help make decisions in other areas of human
## activity and resource development. The vulnerability index system
could be applied to terrestrial as well as aquatic species by adding or subtracting impacting factors, as appropriate. Indexes relating the impact of man upon each North American species could have broad uses in the field of conservation. Population explosions, as well as declines, might be predictable. Human activity could be better adjusted to favor or depress wildlife populations, as appropriate.
We believe that this vulnerability index system has promise for aiding in the decision-making processes upon which future bird conservation will depend.
References
American Ornithologists' Union. 1957. Check-list of North American birds. 5th ed. Lord Baltimore Press, Baltimore, Maryland.
Fay, F. H., and T. J. Cade. 1959. An ecological analysis of the avifauna of St. Lawrence Island, Alaska. Univ. Calif. Publ. Zool. 63(2):73-150.
Gabrielson, J. N., and F. C. Lincoln. 1959. The birds of Alaska. The Stackpole Company, Harrisburg, Pa., and Wildlife Management Institute, Washington, D.C. 922 pp.
Gibson, D. D. 1970. Check-list of the birds of Alaska. Univ. of Alaska, Fairbanks. 2 pp.
Isleib, M. E., and B. Kessel. 1973. Birds of the North Gulf Coast-Prince William Sound region, Alaska. Univ. of Alaska Biol. Pap. 14. 149 pp.
Kortright, F. H. 1942. The ducks, geese and swans of North America. Wildlife Management Institute, Washington, D.C.
McHarg, I. L. 1969. Design with nature. Natural History Press, Garden City, N. Y. 197 pp.
Murie, O. J. 1959. Fauna of the Aleutian Islands and Alaska Peninsula. U.S. Fish Wildl. Serv., N. Am. Fauna 61:1-364.
Palmer, R. S. 1962. Handbook of North American birds. Vol. 1. Yale University Press, New Haven, Conn. 567 pp.
Peterson, R. T., G. Montfort, and P. H. D. Hallom. 1967. A field guide to the birds of Britain and Europe. Houghton Mifflin Co., New York.
Robbins, D. S., B. Bruun, and H. S. Zimm. 1966. Birds of North America, a guide to field identification. Golden Press, New York.
Sanger, G. A. 1972. Preliminary standing stock and biomass estimates of seabirds in the subarctic Pacific region. Pages 589-611 _in_ A. Y. Takenouti et al., eds. Biological oceanography of the North Pacific Ocean. Idemitsy Shoten, Tokyo.
Sparrowe, R. D., and H. M. Wight. 1975. Setting priorities for the endangered species program. Proc. N. Am. Wildl. Nat. Resourc. Conf. 40:142-156.
Stout, G. D., P. Matthiessen, V. R. Clem, and R. S. Palmer. 1967. The shorebirds of North America. Viking Press, New York. 270 pp.
U.S. Fish and Wildlife Service. 1974. Birds of the Aleutian Islands National Wildlife Refuge. Washington, D.C.
U.S. Forest Service and Alaska Department of Fish and Game. 1970. Birds of Southeast Alaska, a check-list. The agencies, Juneau, Alaska. 12 pp.
PROGRAMS AND AUTHORITIES RELATED TO MARINE BIRD CONSERVATION
Programs and Authorities Related to Marine Bird Conservation in Washington State
by
Ralph W. Larson
Washington Department of Game 600 North Capitol Way Olympia, Washington 98504
Abstract
Seabirds are one of the most visible biological components of ecosystems, and yet little is known about them. They could readily be used as an index of marine environmental quality if adequate studies were conducted to determine populations, habitat needs, and causes of fluctuations in abundance. The lack of adequate funding at the State level has precluded necessary studies to make these determinations and to provide habitat protection and preservation.
The State of Washington has developed a funding source for protection, preservation, and enhancement of nongame wildlife, which includes seabirds. The sale of personalized license plates for vehicles is now providing some funds for nongame wildlife management--funds which should increase as the popularity of the licensing program increases. Outdoor Recreation Bonds are providing funding for habitat preservation. Authorities provided the Washington Game Department are adequate to manage and protect seabird species. Other State laws offer additional protection to their habitat--specifically the Shoreline Management Act of 1971 and the State Environmental Act.
It has been often stated that seabirds are one of the most visible biological components of ecosystems, and yet little is known about them. Most studies to date have been on fish, and because of their recreational and commercial value, the concern for maintaining the marine environment has been primarily a result of the concern for maintaining the fishery resource. The visible knowledge of the fishery resource, however, becomes an "after-the-fact" knowledge since the status of the stocks relates to the value and amount of the fishery--a fishery resulting from survival under the surface in the marine environment that can be very secretive about its quality until it is too late to do something about it. Seabirds, however, are visible above the surface, in numbers that can reflect changes in the marine environment that occur below the surface, since many depend on the subsurface quality that reflects populations of fish.
Studies in Oregon have indicated that consumption of pelagic fish by murres (_Uria_ spp.), cormorants (_Phalacrocorax_ spp.), storm-petrels (_Oceanodroma_ spp.), and shearwaters (_Puffinus_ spp.) account for about 22% of the annual production of various species of these fish. A decline in this food source will reflect a decline in the seabird population. Why then should it be necessary to use only fish populations as an index of marine environmental quality, when seabirds can more readily be observed and can reflect the same changes that occur?
As a public wildlife agency, the Washington Department of Game is often attempting to justify the value of seabirds, and sometimes that is not easy. When fishermen complain that the seabirds are eating all of the food of our mighty salmon, and hunters indicate little compassion because the birds have no value to sport hunting, one has to think a little to explain their value. However, rhinoceros auklets _(Cerorhinca monocerata)_ do drive herring into ball-shaped schools, which attracts salmon in search of food--which in turn provides a signal to fishermen that salmon may soon be in the area. Explaining value to the hunter is a bit more difficult, but anyone who has taken the time to go out on our marine waters and observe the many species of seabirds and watch them flying and feeding cannot help but be fascinated by them. The flight of thousands of murres skimming over the water surface and somehow managing not to dash headlong into a wave is a fascinating sight.
We who are in fish and wildlife work have had to readjust our thinking and values during recent years. Our primary programs and concerns for many years were with the fish, birds, and animals that were of value to fishermen and hunters. Species of wildlife that we now classify as nongame received incidental benefit from programs related to game fish, game birds, and game animals, but we did not do badly in maintaining and enhancing these incidental wildlife species, mostly by indirection. However, in the last few years our Department, at least, has taken on a new responsibility and a new look as related to nongame wildlife.
Our first positive step in this direction was to develop a funding source for nongame wildlife programs. Our funding attempt charted its way through stormy waters, but finally ended up being voted on by the citizens of the State. Our citizens passed Referendum 33, which provided funds to the Department for nongame wildlife programs from the sale of personalized license plates. Although the funds have not been adequate, they are a step in the right direction and have permitted the Department to engage in a modest program of research and management. We have placed one person in charge of our program to do the planning and programming so necessary for developing an effective, growing program. During the 1st year of operation, we contracted studies on the rhinoceros auklet, the tufted puffin _(Lunda cirrhata)_, and the black oystercatcher _(Haematopus bachmani)_. These studies have provided a basic knowledge of some of the problems facing these seabird species. As funds increase, additional studies will be made to provide more information on these birds and others.
During the 1975 legislative session we were successful in amending the personalized license program to include automobiles other than passenger cars--a step which should further enhance our funding. We anticipate that funding will increase from the sale of these license plates each year. They serve as their own advertisement, and as more plates are sold, the exposure to the public increases. We anticipate that within the next few years the funding should reach $150,000 per year--a modest sum to be sure, but nevertheless adequate to establish a viable program.
We have been involved in studies funded through other agencies that involve seabirds. The principal reasons for the studies are not seabirds, but they become an integral part of any analysis that must be made of our saltwater environs. One such study involves a comprehensive status survey of the marine shoreline fauna of Washington. The Department of Ecology has provided the funding as a part of their analysis of resources that may be adversely affected by oil spills and economic development of our shorelines. This study will be the first one designed to comprehensively identify wildlife species associated with our shorelines and will determine the species, their status, location, and habitat. This study will provide a basis for readily identifying visually the results of oil spills and of the economic development of critical habitat areas, and provide sound basic data for use in combating destructive projects in the marine environment.
We are finding that you cannot separate functions of other governmental agencies that deal with marine waters from seabird analysis. Pollution responsibilities, shoreline management, coastal zone management, clam dredging, channel dredging, erosion control, housing development, industrial expansion, shipping port development--to name a few--all must have some effect on our seabird species. Therefore, we must concentrate on obtaining an adequate data base to insure the perpetuation of these valuable marine species.
As I indicated earlier, the Department of Game has not had a special program to manage seabirds in the past, but this should not indicate that we have not assisted in maintaining the seabird resource. Our basic land acquisition program designed for waterfowl enhancement has benefited seabirds. We now own some 15,500 acres of lands, tideland, and marshes bordering the marine waters (including our Skagit and Nisqually holdings) which provide habitat and protection for many seabirds. We also recently acquired 48 acres on Protection Island, designed to protect the nesting area of the rhinoceros auklet. This purchase was an excellent example of how combined efforts of several groups accomplished a nearly impossible goal.
Protection Island had been subdivided for summer home development and many lots had been sold. The developer, however, got caught in the requirements of our Shoreline Management Act with his last subdivision. The uproar caused due to the use of this subdivision by auklets created an atmosphere that made subdivision a real conservation issue. The outspoken critics of the project from the Audubon Society, Fish and Wildlife Service, independent conservationists, and our Department enlisted the aid of Nature Conservancy to negotiate for purchase of this subdivision, and after lengthy negotiations the option was obtained, and the Department purchased the land from the Nature Conservancy with funds provided by the Interagency Committee for Outdoor Recreation. The area now is destined to be a seabird sanctuary, with limited public viewing and incidental recreation use. This project is an excellent example of the power of cooperative efforts by conservationists to protect a resource.
The State of Washington now has a reasonably good legislative base to insure constructive programs for management of our seabird resource. Our legislative authority lies in State statutes under Title 77. These authorities first provide that the wild birds, wild animals, and game fish of the State are the property of the State and that they shall be preserved, protected, and perpetuated. Any regulations for taking shall be designed so as to not "impair the supply thereof."
The commission also has the authority to classify wild birds. Seabirds, other than hunted species, fall into the category of nongame birds. We also have the authority to regulate the propagation and protection of wild birds, develop rules and regulations for taking them (or to prohibit taking them), and to create game reserves and closed areas where necessary to protect various species. Our authorities also include the obligation to enforce the laws, rules, and regulations pertaining to the protection of all wild birds.
The Department may also acquire land for habitat and for sanctuaries for nongame birds and may exchange lands for these purposes. We may also enter into agreements with the Federal Government, persons, and municipal subdivisions of the State for all matters relating to propagation, protection, and conservation of all wild birds, and may lease State lands for this purpose.
We believe our authorities are now totally adequate to satisfactorily manage the State's marine bird resources.
In addition to our personalized license plate legislation, which earmarks funds for nongame wildlife, other State laws and programs assist in protection of this resource. One program that has assisted materially in providing funds for habitat acquisition is a bond issue passed by citizens of the State designed to acquire and develop recreational land in the State for public use. Our Interagency Committee for Outdoor Recreation provides the necessary mechanism for funding of projects, using these bond monies to match Federal funds. Although recreation is a key factor in obtaining funding, it is still possible to acquire key habitat for wildlife and develop a people-use program around the primary purpose for acquisition.
The purchase of a portion of Protection Island was accomplished by use of these funds, as I indicated earlier, and we are now working again with Nature Conservancy to acquire key bald eagle habitat on the Skagit River in northwestern Washington. The bond issues total some $50 million, of which this Department receives about 15%. The State now is in its third bond issue, and we hope the citizens will continue to support this program.
One of the newer laws is the Shoreline Management Act of 1971. This act provides for development of comprehensive shoreline management programs designed to control the development of these areas to insure protection of the public interest, while still recognizing and protecting private property rights consistent with this public interest. These plans must be developed with citizen involvement. Shoreline classification generally falls into four categories--natural, conservancy, rural, and urban. The natural classification can accomplish the most substantial benefit for marine birds. Provisions are also made for protection of "shorelines of statewide significance." Plans for these areas must give preference to uses favoring the public and long-range goals. These shorelines cover the areas between low and high tide levels on inland waters and high water and the western boundary of the State on our Pacific Ocean coast.
Our State Environmental Policy Act, which requires that environmental impact statements be prepared for various programs and developments, gives our Department an opportunity to insure that our valuable wildlife resources are given consideration during the planning phase of the proposed project.
The Department feels that our authorities at this time are adequate to protect marine bird populations and their habitat. The one lacking factor, as usual, is the funding for both adequate management programs and habitat protection. Our marine habitat is rapidly being developed for recreational homesites and public use which can eliminate key habitat use. A greater public awareness of the needs of marine birds can be a help in preventing destruction of their habitat; however, money talks the loudest. The acquisition of these key habitats is the most positive means of insuring their retention. We have no solution at this time to the funding problem and only hope that someone smarter than we are can provide an acceptable solution before all of our efforts become too little and too late.
Programs and Authorities of the Province of British Columbia Related to Marine Bird Conservation
by
W. T. Munro
British Columbia Fish and Wildlife Branch 300-1019 Wharf Street Victoria, British Columbia, Canada V8W 2Z1
and
R. Wayne Campbell
British Columbia Provincial Museum Victoria, British Columbia, Canada
Abstract
British Columbia Provincial agencies are given authority for protecting marine birds and their habitats by the Provincial Wildlife Act, the Parks Act, and the Ecological Reserves Act. The Provincial Museum Act accommodates research on marine birds. The Fish and Wildlife branch has protected over 30,000 ha of intertidal estuarine habitat in the form of reserves and has conducted limited inventories of birds on the Queen Charlotte Islands and northern mainland coast. The Provincial Museum has conducted inventories and life-history studies of marine birds and maintains a repository for information on seabirds, including a catalog of colonies. Pollution from oil and chemicals, improper logging practices, and disturbance by boating recreationists are the most apparent threats to the well-being of birds. Additional inventories and the determination of seasonal distribution are among the information needed to better protect the marine birds of British Columbia.
Most marine-associated birds in Canada are covered by the Migratory Birds Convention Act and are therefore federally protected. In British Columbia additional protection is provided by the Provincial Wildlife Act. Several other provincial acts provide authorities related to seabirds. The Provincial Museum Act permits research related to natural history; the Parks Act and Ecological Reserves Act provide for the protection of habitat and prohibit harassment of wildlife within park and reserve boundaries; and the Firearms Act permits the closure of areas frequented by selected wildlife to the discharge of firearms. The fact that several authorities for the protection and conservation of marine birds are available does not mean that they have been used to full advantage.
British Columbia's irregular shores provide thousands of kilometers of coastline, much of which is used by marine birds for nesting and wintering as well as during migration. Through legislation of different types, some of the more ecologically important and unique sites have been protected. Twelve "ecological reserves," which are basically inviolate preserve areas, provide habitat for and protection to a number of major breeding colonies. Over 30,000 ha of intertidal estuarine habitat has been protected by the provincial Fish and Wildlife Branch in the form of reserves. Less than half of the total area is in Order-in-Council reserves (passed by the Provincial Cabinet), which afford strong protection; the rest is in departmental map reserves, which merely means other agencies must inform the branch before they disturb them; they are hardly secure. Provincial Parks Branch protects other areas used by marine birds by incorporating them within parks.
Research and conservation of seabirds in British Columbia have not been a high priority in the Fish and Wildlife Branch, basically because seabirds are not consumed by people. Our primary interest in seabirds has been in their role as a life support system for the peregrine falcon _(Falco peregrinus)_. Most Fish and Wildlife Branch reserves have been established to protect estuarine habitat for fishes, waterfowl, and shorebirds rather than for true seabirds. That situation is not likely to change in the near future unless additional funds become available to the Branch. About the most we can expect to do is designate key areas as sanctuaries or wildlife management reserves. Under the folio and referral systems now operational among resource agencies in British Columbia, we have the opportunity to advise other disciplines against approving practices that would adversely affect wildlife. By those methods we are attempting to protect critical seabird habitat. It must be stressed, however, that we can only advise; we cannot force other agencies to follow procedures we suggest.
The only significant work relating to seabirds in which the Fish and Wildlife Branch is presently engaged involves inventory of specific sites on the Queen Charlotte Islands and the northwest mainland coast. Those areas are ones on which we expect to find seabird colonies and where applications for logging are pending. To enable us to advise the Forest Service on the wildlife values of those sites, we began field work in the summer of 1975.
The Federal Government, in comparison to what it has done on the east coast and in the north of Canada, has been negligent in its support of seabird conservation on the west coast. By far the most seabird research by a government agency in British Columbia has been accomplished by the staff at the Provincial Museum in Victoria. In the past, beginning in the 1940's, museum personnel (mainly C. J. Guiguet) explored and inventoried seabird colonies along the British Columbia coast. Most work then was exploratory, and little quantitative information was gathered. More recently, precise counts have been obtained of seabirds nesting in the Strait of Georgia, Juan de Fuca Strait, the central west coast of Vancouver Island, the northern mainland coast, and the east coast of the Queen Charlotte Islands. That information, along with quantitative data gathered in the summer of 1975, will be used to update the "Catalogue of British Columbia Seabird Colonies" published in 1961 by the museum.
The museum has a number of programs under way.
• A cooperative survey with Washington State of colonies of the double-crested cormorant _(Phalacrocorax auritus)_ in the Pacific Northwest. To limit disturbance, that survey is to be conducted at 5-year intervals beginning in the summer of 1975.
• A survey of all islands, whether or not they are supporting seabirds, in the Strait of Georgia and Juan de Fuca Strait in 1980, to detect changes in populations after 1974.
• Monitoring changes in seabird populations along the west coast of Vancouver Island, gathering data for all islands there. Permanent quadrats will be established on ecological reserves in the area to help detect such changes. As a result of such quadrats having been set up in 1967 on Cleland Island and being re-examined in 1974, we can document a significant decrease in Leach's storm-petrel _(Oceanodroma leucorhoa)_ and a corresponding increase in rhinoceros auklet _(Cerorhinca monocerata)_.
• Mapping vegetation substrate as it relates to seabird populations on selected islands in the Province.
• Investigating differences in eggshell thickness between eggs within clutches of glaucous-winged gulls _(Larus glaucescens)_ near Victoria.
• A saturation banding program for cormorants (_Phalacrocorax penicillatus_, _P. pelagicus_, and _P. auritus_) on south-coast colonies.
• Continued banding of select colonies of glaucous-winged gulls which began in the 1960's. Life tables, survivorship curves, and dispersal patterns should result.
The museum also acts as a repository for information on seabirds in British Columbia and maintains files on the history of seabird islands as well as references to literature published on all seabirds in the Province. The references include unpublished theses and reports. This information is easily retrievable--not a small contribution in today's paper-producing society.
Future programs planned by the Provincial Museum, in addition to the continuance of some of those already mentioned, include a system of monitoring colonies every 5 to 10 years, depending on the sensitivity of the species involved, to detect changes in population numbers and distribution. It is also hoped that the first complete provincial census, with cooperation from Federal and provincial agencies, naturalist groups, and the like, can be budgeted and arranged for in the summer of 1980. That census could conceivably be expanded to include the entire Pacific coast of North America.
Some research on the breeding biology of seabirds has been conducted by universities, notably the University of British Columbia under the guidance of R. H. Drent and M. Udvardy. We expect that graduates returning to coastal universities will continue that work. The section of government dealing with ecological reserves has just recently received funding to permit field studies on reserves harboring marine birds. J. B. Foster, Coordinator of Ecological Reserves, emphasizes that research by other agencies is encouraged under permit on ecological reserves.
There are a number of threats to seabirds in British Columbia. Along with the chemical pollutants in their environment and food, logging, and the specter of huge oil tankers plying the west coast, we are greatly concerned by the potential threat of boating enthusiasts and recreationists. Well-meaning but uninformed vacationers and boaters stopping to visit or picnic at seabird islands can do serious damage to nesting seabirds. The possibility of loss of habitat to seabirds from people searching for island summer homes poses a threat, and indeed some seabird islands have already been lost to speculators. With increased leisure time and travel the potential of unintentionally introducing predators, such as rats (_Rattus_ spp.) and snakes, to seabird islands is great. Intentional or accidental introduction of mammals, such as mink _(Mustella vison)_, rabbit (_Sylvilagus_ spp.), fox (_Vulpes fulva)_, and raccoon _(Procyon lotor)_, to islands is another serious threat to the future existence of seabird populations. The recent unauthorized and apparently unsuccessful introduction of mink on the Queen Charlotte Islands could have resulted in the eventual devastation of seabird colonies there and on adjacent islands. The destruction of habitat by logging near colonies on large islands and complete logging on small offshore islands will no doubt adversely affect some seabird populations. Competition between increasing numbers of gulls (_Larus_ spp.) and certain species of seabirds (e.g., storm-petrels and cormorants) may result in reduced numbers of the seabirds.
What types of programs are needed? About 80% of all known seabird colonies in British Columbia have been investigated to date, and a modest program to monitor changes has been established. We do, however, require exploratory work along the west coast of the Queen Charlotte Islands and northern mainland coast. We need to know more about the breeding biology and reproductive potential of each of the species nesting in the Province, as well as about their adaptability to different habitats. Will some burrow-nesting alcids use man-made tubes erected in otherwise marginal habitat? Can and should more man-made habitat be created for cormorants that have been displaced from ancestral breeding grounds?
Of immediate urgency is exploratory work involving seasonal distribution, abundance, and flight lanes of pelagic seabirds along the coast of British Columbia--especially the northern portion. We lack the base-line data which could help influence routes of oil tankers to lessen the potential danger of spills to marine birds. We know little about the winter distribution of marine birds, especially alcids.
As a general rule, offshore islands of less than 100 ha should be protected completely from logging, and the larger ones supporting major seabird colonies should have some protection from development. We must also consider the possibility of preserving some islands which may act as buffer areas and provide potential alternate habitat to seabirds.
Another concern is the effect of commercial and sport fishing in the Province on food supplies for seabirds, and what damage, if any, gillnetting may have on diving seabirds. Perhaps we should discourage fishing by nets in areas where large numbers of seabirds aggregate to feed.
We also need to know more about the effects of chemical pollutants on individual species and on their reproduction. Of paramount importance, and one which biologists tend to neglect, is communication among all disciplines interested in seabirds. For example, a comprehensive file of the history of seabird colonies in British Columbia is established at the Provincial Museum. It would be a waste of time and money to duplicate that file and have three or four scattered across the country. We would be better advised to tackle another phase of work yet to be accomplished. Communication assures that seabirds benefit and are not unduly harassed.
Annual meetings, both local and international, of persons interested in marine birds should be arranged so that problems relating to seabirds can be discussed. For example, populations of glaucous-winged gulls in British Columbia have increased exponentially in the past 10 years. If they are a threat to the existence of other seabirds (e.g., Leach's storm-petrel, double-crested cormorants), should they be controlled, and, if so, how? Such meetings would also help develop a pattern of universal census methods and techniques that could be put to use along the Pacific Coast to provide comparable data from different areas.
Finally, in today's world, natural resource agencies must operate on limited funding. How can one convince administrators to divert a significant portion of those funds to the investigation of species that are widely regarded as having little social importance?
A detailed bibliography of seabirds of British Columbia is available from either of us.
We thank D. F. Hatler, J. B. Foster, and A. L. Allen for comments on the manuscript.
Petroleum Industry's Role in Marine Bird Conservation
by
Keith G. Hay
American Petroleum Institute 2101 L Street NW Washington, D.C. 20037
Abstract
Despite improved safety practices, engineering, and navigational skills, marine tanker transportation will not be 100% accident free. The industry seeks to mitigate wildlife losses through improved technology, research in the rehabilitation of species exposed to oil, and the development of oil spill/wildlife contingency plans.
Oil spills and marine birds not only constitute a deadly mix but have proved to be one of our toughest environmental problems to solve. The rehabilitation of these tragic victims is plagued with controversy, emotion, apathy, and biological unknowns. The costs have been high and the survival rates low. During the last 10 years, a few dedicated people working here and in Europe have reversed this trend. They have, in addition, taken steps to develop contingency plans and conducted research to reduce seabird mortalities from oil spills. I present a brief status report on their progress and the melange of problems involved.
The unfortunate encounter between spilled oil and marine birds is not new. It goes back at least to the turn of the century, when coal-burning steamships and sailing clippers were replaced by oil-fueled vessels. Since then thousands of marine birds have succumbed to floating oil, especially during World Wars I and II (Blanks 1942) and in recent spills here and off the coast of Europe (Clark 1969).
With the current and projected demands for energy in the United States and with expanded tanker traffic and accelerated development of offshore petroleum reserves, the oil-contaminated ("oiled") bird is not going to go away. Periodically, this ugly problem will arise, despite the efforts of the petroleum industry to improve its safety practices, engineering, and navigational skills. Unfortunately, the problem is the product of the inherent fallibility of man and his imperfect machines.
We cannot ignore the situation. We must here, as elsewhere, improve our technology and mitigate the impact.
A study of more than 100 spills that occurred throughout the world between 1960 and 1971 revealed that about 1 in 5 spills (20%) involved 50 or more birds (Ottway 1971). Nearshore spills have a far greater effect on waterfowl than do spills occurring several miles or more offshore.
In the 1967 _Torrey Canyon_ tanker spill, some 8,000 oiled birds were rescued. About 6,000 were picked up alive in England and about 2,000 in France, at a cost estimated at $160,000 (Clark 1969; Bourne 1970). Less than 5% of those treated by British authorities survived for release some months later. The survival rate of those rescued in France is unknown.
In 1969 the Santa Barbara spill resulted in the treatment of 1,575 marine birds, of which 169 were eventually released. Many of those released were found dead within a short time (Smail 1971).
In 1970 the tanker _Delian Apollon_ was responsible for a spill in Tampa Bay, Florida. Thousands of seabirds were lost. No exact count was taken, but hundreds of birds were cleaned and farmed out for rehabilitation. Reports show that many of the birds were returned dead within a few days (Smithsonian Institution 1971).
In 1971, when two tankers collided under the Golden Gate Bridge at the mouth of San Francisco Bay, the resulting spill involved some 4,686 oiled birds taken to cleaning centers (Lassen 1972). Eight months later the last of 200 survivors (less than 5%) were released at a cost estimated at $900 per bird (Smith 1975).
The most vulnerable species involved in spills have been the oceanic birds such as the alcids--murres (_Uria_ spp.), auks (_Pinguinus_ spp., _Alca_ spp.), puffins (_Fratercula_ spp., _Lunda_ spp.), and guillemots (_Cepphus_ spp.). Other species less affected included ruddy ducks _(Oxyura jamaicensis)_, scaup (_Aythya marila_, _A. affinis_), scoters (_Melanitta_ spp.), mergansers (_Lophodytes_ spp.), oldsquaws (_Clangula_ spp.), and goldeneyes (_Bucephala_ spp.). Grebes (_Podiceps_ spp.), eiders (_Polysticta_ spp.), loons (_Gavia_ spp.), and cormorants (_Phalacrocorax_ spp.) are also frequently involved. Ruddy ducks and scaup are particularly vulnerable during winter on large river systems with heavy oil transport traffic. Fortunately, none of the above species have been reported in jeopardy as a result of spills in American waters.
In Europe and South Africa, however, it is believed that oil pollution is responsible for a steady decline in seabird colonies. For example, in known oil-dumping areas in the Baltic Sea, where some mortality of oldsquaws has been associated with surface oil, their population has dropped to about one-tenth of the pre-World War II level (Bergman 1961). Other authors report that oil spills have reduced the number of scoters in the Baltic and off southeast England (Atkinson-Willes 1963). The auk populations off the coast of England have been reported to be substantially decreased by oil pollution (Parslow 1967). Tankers traversing South Africa's Cape of Good Hope are said to be responsible for the reduction of jackass penguins, _Spheniscus demersus_ (Rowan 1968). Oil pollution, especially sustained pollution, has thus been cited as a limiting factor on certain seabird populations.
Estimates of seabird mortalities from an oil spill are imprecise; they may differ by thousands of birds. It is believed that only a small fraction of the birds killed in a spill wash up on the shore. Some authors have even speculated that the death rate at sea could range from 6 to 25 times the number washed ashore (Tanis and Mörzer-Bruyns 1968).
In contrast to terrestrial birds and semiaquatic species (e.g., ducks; geese; coots, _Fulica_ spp.; or gulls, _Larus_ spp.), totally seaborne species have a restricted reproductive potential. Many, such as the alcids, do not breed until they are 3 or more years old, and lay only one egg per year. Only one in five survives to go to sea.
Until about 5 years ago we knew little about seabirds. They are not game species (they taste fishy) and thus do not constitute an important economic resource. They have never been the subject of intensive waterfowl management or research by either State or Federal governments.
During the last 5 years a small group of people here and in England have been studying marine birds--their distribution, population status, physiology, diseases, and husbandry in captivity. Four organizations have primarily been involved: The American Petroleum Institute (API); the Wildlife Rehabilitation Center at Upton, Massachusetts; England's Advisory Committee on Oil Pollution of the Sea; and the International Bird Rescue Research Center in Berkeley, California. They have encountered many common biological and people problems, some of which I discuss here.
Biological Problems
The recuperation record for oiled seabirds in the past has admittedly been dismal. A few birds have been returned to nature, but only after a long and costly period of care. In the process, semidomestication often takes place. The percentage of cleaned birds that actually survive after release is even smaller. One should not infer from this small percentage that rehabilitated birds cannot readjust to life in the wild. Several successful reintroductions have been documented. U.S. Fish and Wildlife Service bands were returned from two western grebes that were cleaned and released after the 1971 San Francisco spill. One bird was picked up a year later near Treasure Island, California, and the second after almost 2 years, in the State of Washington (Fletcher 1973).
Survival rates have zoomed with recent strides in cleaning technology and husbandry. The International Bird Rescue Research Center reported a survival rate of 41%, based on hundreds of birds and about 20 different species over a 2-year period (Smith 1975). In South Africa, where powdered clay was used as a cleaning agent on jackass penguins, nearly 50% survived, although exact percentages have not been published (Edwards 1963; Holmes 1973). Rapid retrieval, the relatively small groups of birds treated, and expert cleaning and husbandry techniques are largely responsible for high success ratios. Rehabilitation success is measured not only in terms of percent survival but also in terms of median length of captivity and average cost per bird.
Rescued oiled birds arrive at cleaning centers under a wide range of physical conditions. Before capture they may have spent hours or days in water, during which their energy has been continuously drained. The oil destroys the bird's protective insulation, and metabolic rate must be increased to sustain body temperature. Constant preening also takes energy. Food demands increase, but feeding attempts, especially for diving birds, are thwarted by oil-fouled plumage. A bird may arrive at the cleaning center under stress, chilled, exhausted, dehydrated, starved, and ill from ingested oil. Cold weather accentuates these conditions. Often such birds are jammed together with other species, hauled long distances, and immediately put through a series of cleaning processes that would leave even a healthy bird weak and in a state of shock. One marvels at the stamina of the survivors.
In most past spills, every bird found was routinely cleaned regardless of its condition. Instead of attempting to reclaim all birds, a selective judgment should be made. If a bird's physical condition makes its chances of survival nearly impossible, it should be humanely killed (except for rare or endangered species). This would enable workers to devote more time and care to birds having a reasonable chance at survival.
Fletcher (1973) stated that many variables affect bird survival: weather conditions, the type and amount of oil in and on the bird, the species, the distance of the spill from the shore, the time lag from initial fouling until initial treatment, the degree of stress a bird is subjected to, the husbandry techniques used, the time of release (the sooner released, the higher the apparent survival), the number of birds being cared for (the fewer birds being handled, the higher the survival rate), the quality of the facilities available, and the training and experience of the people handling the birds.
Many of the above biological problems are under study here and in Europe, including the following.
• The effect of ingested oil on the mucosal transport mechanism of marine birds. To use seawater, birds must be able to transport sodium ions through the gut and expel the excess salt through the nasal passages. Oil can block the mucosal ion transport mechanism, resulting in dehydration and eventual death.
• The development of a successful program of hormonal and electrolyte therapy to restore osmotic balance and the functioning of the salt glands in contaminated seabirds.
• Treatment and prevention of aspergillosis (fungus infection); septic arthritis or "bumble-foot" (joint capsule infections); breast sores (especially in seabirds confined on hard surfaces); eye lesions (caused by ammonia fumes from unsanitary pens); dehydration and hypoglycemia; lipid pneumonia; and bacterial infections.
• Treatment of stress after capture, including perfection of handling and cleaning techniques, administration of proper steroids, crowding, light, temperature, noise levels, and so on.
• Development of proper nutritional regimes for certain species and feeding techniques to eliminate forced feeding.
• The establishment of criteria for confident recognition of terminal pathological conditions in oiled birds.
• Determination of optimum density of confined birds to insure healthy conditions and adequate room for preening.
• Determination of proper time and conditions for reintroduction of the birds into their native habitat.
People Problems
Handling an over-responsive and emotional army of bird-cleaning volunteers and training them to play constructive roles is a major undertaking. Planning, cooperation, understanding, patience, and clear direction must be developed. In the absence of these virtues, chaos can and has prevailed.
The San Francisco Bay oil spill of 1971 was a classic example. There was virtually no State or Federal coordination. Splinter groups of volunteers established their own "treatment centers" and jealously guarded their patients. Some actually absconded with their pet patients to seek better care elsewhere. Long hours, fatigue, and frustrations led to dissension and bitter quarrels. Antiestablishment sentiment was rampant.
Instant experts on bird cleaning, avian medicine, and nutrition appeared or developed overnight. Veterinarians volunteered their services, but their knowledge of oiled-bird treatment was limited. A wide variety of food (from canned dog food to live shrimp) was given the birds. Forced feeding was routine. Medications and vitamins of all kinds were also administered. Needless to say, the states of the art in treating oiled birds and handling volunteers were both in their infancy. For both, the success ratio was near zero.
To prevent such fruitless efforts and the frantic, unorganized response that prevailed, a well-designed contingency plan for wildlife involved in an oil spill is needed.
Contingency Planning
It is only prudent to take reasonable measures to prepare for oiled-bird emergencies. This is especially true in regions where bird concentrations and oil shipment traffic converge. Almost equal attention must be devoted to handling volunteers as to handling birds. Safety is a major consideration. The sharp beaks of birds can be very dangerous.
A model State contingency plan should include the following:
• A list of State and Federal agencies to be alerted, including 24-h, 7-day-a-week telephone numbers, and names of individuals to contact.
• Clarification of the roles of State and Federal agencies under the Regional Response Plan of the National Oil and Hazardous Substances Pollution Contingency Plan.
• A list of State and Federal laws pertaining to possession of birds and mammals.
• An updated roster should be maintained of team members, assignments, and responsibilities for inland and marine spills, including discovery and notification, record keeping, public information, containment and counter-measures, wildlife protection, and cleanup, restoration and evaluation of effects on the biota.
• A list of individuals or organizations that possess skills and experience in treatment of oiled birds (locally and nationally).
• Location of emergency wildlife reception and treatment centers.
• A list of the necessary supplies, equipment, and holding facilities for cleaning, treating, drying, and post-care operations. Such information can be obtained from:
--California Department of Fish and Game, Oil and Hazardous Materials Contingency Plan (July 1974)
--International Bird Rescue Research Center, Aquatic Park, Berkeley, California 94710
--American Petroleum Institute, 2101 L Street, Northwest, Washington, D.C. 20037
--Wildlife Rehabilitation Center, 84 Grove Street, Upton, Massachusetts 01568
• An organizational plan which includes assignments of duties and responsibilities for personnel manning a bird-cleaning center. In addition to bird cleaning and husbandry, assignments must be made for record keeping, internal communications, public relations, logistics (supplies), security, sanitation, safety, and meals.
• A slide lecture or film to instruct volunteers in the correct techniques for handling, cleaning, and post-care of oiled birds.
• A selected bibliography of key references on oiled-bird cleaning and care.
• Appendices to the plan should include maps of the major coastal oil terminals, bays, and estuarine areas with heavy oil transport traffic. Map overlays would depict the location of resident species and the migratory patterns, species composition, relative abundance, and winter concentration areas of migrants. Additional overlays would locate commercially important demersal seafood areas (e.g., oyster and abalone beds, lobster and crabbing locales) and marine mammal habitats. Further refinement of an atlas could include information on tides, prevailing winds, ocean currents, and water mass movements to assist in predicting the path of spilled oil.
What Has Been Accomplished
The petroleum industry, through the API, took prompt steps to mitigate the problem after the first seabird mortalities were reported from Santa Barbara in 1969. They commissioned a young aviculturist, Philip Stanton, who has extensive experience working with wild waterfowl, to start a research program on cleaning and caring for oiled birds. At his Wildlife Rehabilitation Center at Upton, Massachusetts. Stanton, with the help of API, has been conducting research on oiled birds for 7 years. He is also an assistant professor of biology at nearby Framingham State College. Stanton's studies (unpublished) include investigations on food shape and color preferences in wild ducks, the effects of lengthened photoperiods on breeding of arctic geese, and the effects of diets of varying protein concentrations on growth and development of the common eider duck.
As a result of his research on cleaning techniques and agents, Stanton has recommended a nontoxic liquid cleaner called Polycomplex A-11. Although not perfect, it is one of several cleaning agents being successfully used today. He has authored a "how to" guide for oiled-bird treatment entitled "Operation Rescue" and prepared a companion bibliography (Stanton 1972). These booklets have been distributed throughout the United States to State and Federal agencies and conservation organizations. He has provided consulting services at numerous spills and has worked to establish oiled-wildlife treatment centers in coastal States.
Since 1972 the API has sponsored an avian physiology study at the University of California at Santa Barbara. Under the direction of W. N. Holmes, the studies are directed at the effects of ingested crude oil and petroleum products on marine birds. Holmes has revealed that small quantities of crude oil introduced into the gut of a saltwater-adapted bird can affect the mucosal transport and extra-renal excretory mechanisms, resulting in acute dehydration and eventual death. Dr. Holmes is also examining the effects of the various distillation fractions derived from crude oil and the long-term effects of ingested oil in mature birds. Incidentally, Alaska North Slope oil was found to be almost innocuous when administered to ducklings in amounts similar to the effective doses of other oils (Holmes and Cronshaw 1975).
Refined products (diesel oil, No. 2 fuel oil, and Bunker "C") are known to be more toxic than crude oil. For example, the relatively small spills of Bunker "C" at Tampa, Florida, in 1970 and in San Francisco in 1971 caused approximate mortalities of 90 and 20 birds per ton of spilled product, respectively. The crude oil spills of the _Torrey Canyon_ and at Santa Barbara, however, resulted in mortalities of only 0.5 and 0.6 bird per ton of oil (Clark 1973).
Dr. Holmes is now testing measured amounts of the above refined oils on adult birds. He is determining the degree of dehydration incurred, the resulting pathological changes, and the replacement (hormonal and electrolyte) therapy necessary to rehabilitate the birds.
It is obviously important to keep as many birds away from an oil slick as possible. This was the objective of an API contract with the Av-Alarm Corporation of Santa Maria, California. Their objective was to determine the feasibility of repelling aquatic birds from an area by using an acoustical jamming device as the stimulus.
The flocking instinct in birds provides mutual protection through their almost constant communication with one another. When this (audio) communication is prevented by jamming with high-frequency sounds, the birds immediately leave the area to seek relief. This harmless technique has been used successfully for years to repel agricultural pest birds.
The Av-Alarm device was tested on waterfowl at the Grizzly Island Game Refuge some 48 km north of San Francisco Bay and in the bay itself over a 2-year period (1972-73). Using a single, fixed-location system covering a three-quarter square mile (1.21 km²) area Crummett (1973) repelled 82% of the ducks and 92% of the shorebirds on the Refuge. The intrepid coot, however, was found to be relatively indifferent to the sounds. Immediately upon activation, there was a sudden drop in the bird count, which was followed by a continual decline in numbers.
In tests of the device from a cruising boat in ocean and bay waters, the degree of effectiveness varied by species. Ducks were repelled 100%; pelicans (_Pelecanus_ spp.) 92%; great egrets _(Casmerodius albus)_ 85%; gulls 42%; cormorants 75%; shearwaters (_Adamastor_ spp.) 29%; and murres, 51%.
Grebes and murres dived away from the stimulus, then surfaced and dived again if the threat was still present. To prevent driving the diving species deeper into the center of a slick, investigators recommended that buoyed repelling equipment be placed within the spill area. When the alarm system was used in conjunction with the occasional firing of a rocket or shellcracker, an even greater percentage of birds was repelled.
The International Bird Rescue Research Center, a nonprofit corporation in Berkeley, California, was an outgrowth of the Richmond Bird Care Center that played an active role in the 1971 San Francisco Bay spill. Since that time, a small group of individuals has continued research on bird-cleaning techniques, testing cleaning agents, perfecting husbandry methods, and alleviating stress. Their 41% survival rate speaks for itself. A paper describing their work is being presented at this conference (Smith 1975).
Under a grant from the API, the center is currently evaluating various cleaning agents, and testing the pressurized jet versus serial baths and the re-establishment of feather waterproofing. The center is also perfecting an audio-visual slide presentation that will illustrate how to select the proper cleaning agent, together with the latest bird-cleaning and care procedures.
About 5 years ago, England's Advisory Committee on Oil Pollution of the Sea established a research unit in the Department of Zoology at the University of Newcastle-Upon-Tyne. It was funded by a grant from the Royal Society for Prevention of Cruelty to Animals, the Royal Society for the Preservation of Birds, the World Wildlife Fund Seabird Appeal, and the British Institute of Petroleum.
Their efforts have also led to high survival rates. Focusing primarily on the efficiency of various detergents, they have found that the loss of waterproofing is largely due to soap and oil residues and the disturbance of the feather structure in the cleaning process. Consequently, they have devoted their efforts to selecting detergents that can be completely removed with a minimum disturbance of plumage (Seabird Research Unit 1971).
In May 1974, the API in cooperation with the U.S. Fish and Wildlife Service convened a seminar on Oil Spill Wildlife Response Planning. The 2-day workshop was held at the Patuxent Wildlife Research Center at Laurel, Maryland. Some 70 State and Federal government personnel in charge of oil spill response plans involving wildlife participated. The program addressed itself to fish and wildlife considerations and the role of regional response teams under the National Oil and Hazardous Substances Pollution Contingency Plan. The actions of State wildlife departments, U.S. Fish and Wildlife Service, Environmental Protection Agency, U.S. Coast Guard, and the oil industry in handling spills involving wildlife were examined. The latest oil spill cleanup technology was reviewed, and the workshop ended with demonstrations of the cleaning of oiled waterfowl. Similar seminars were planned for the Gulf of Mexico and the West Coast.
It was obvious from this seminar that the most comprehensive wildlife oil spill contingency plan had been developed by the State of California. Copies of this plan (Oil and Hazardous Materials Contingency Plan, California Department of Fish and Game, July 1974) were later distributed to all coastal States as a prototype or model plan by API.
The U.S. Fish and Wildlife Service has been conducting experiments on various bird-cleaning agents and techniques at its Migratory Bird and Habitat Research Laboratory near Laurel, Maryland. The Fish and Wildlife Service is also working with the API in developing information on migratory patterns and winter waterfowl concentration areas on the East Coast as they relate to petroleum transport traffic and oil terminals.
In Canada, the Petroleum Association for Conservation of the Canadian Environment (PACCE) employed the services of a consulting firm to make a comprehensive review of dispersal and rehabilitation of waterfowl associated with oil spills. The resulting PACCE report (LGL Ltd. 1974) codified what was known about the problem, identified research needs, and developed effective wildlife oil-spill contingency plans for critical areas on Canada's east and west coasts, the Great Lakes, and the Arctic.
The Florida Game and Fresh Water Fish Commission has initiated a program for the rehabilitation and treatment of oiled birds. It is being organized by veterinarian Harold F. Albers of St. Petersburg. He is working in cooperation with the Florida Associated Marine Institutes, the Shell Oil Company, Clean Gulf Associates, and the API.
The Standard Oil Company of California provided a grant to James Naviaux of Pleasant Hill, California, to develop bird-cleaning technology, including the testing of various cleaners. Dr. Naviaux had treated birds from the 1971 San Francisco spill. A publication on the after-care of oil-covered birds (Naviaux 1972) resulted from the collaboration with Alan Pittman, research chemist of the U.S. Department of Agriculture's Western Research Laboratory.
In 1971, the API in cooperation with the National Wildlife Federation (NWF) initiated an NWF/API Fellowship program. One of the first grants under this program was to Charles W. Kirkpatrick, Professor of Wildlife Management at Purdue University. He and assistants studied for 4 years the nesting ecology and productivity of the emperor goose _(Philacte canagica)_ in the Igiak Bay area of the Yukon Delta in Alaska (Eisenhauer and Kirkpatrick 1977).
An extensive program of marine bird research was initiated on the North Slope of Alaska by the Atlantic Richfield Company in 1969. It has been continued ever since and includes the acquisition of extensive base-line data on all waterfowl, including June surveys of breeding pair counts and August surveys for brood counts. The results of these surveys for 1969-73 are presented by Gavin (1975).
Base-line data on marine birds of the Gulf of Alaska are currently being collected and compiled through grants to various universities and institutions by the American petroleum industry. These data will constitute elements of a report on the environmental status of the Gulf of Alaska. Such information is essential prior to development of the Gulf's offshore petroleum resources.
Marine Mammals
Most sea mammals are relatively resistant to oil slicks and tend to avoid contaminated waters. As a result, little research has been conducted on cleaning and treatment techniques except for experiments on live beavers and on the carcasses and pelts of sea otters and beavers.
No sea otter or seal has ever been oiled and subsequently cleaned in an oil spill situation. It is possible, however, that a spill could have significant adverse effects on sea otters and fur seals, especially at a rookery during the pupping season. These animals depend on an air blanket trapped in their dense underfur for warmth and buoyancy. Any form of pollutant, especially oil, could penetrate the outer guard hairs and underfur and allow water to reach the skin, with disastrous effects.
Seals and otters are powerful animals, and the larger males and females can be quite aggressive and dangerous. Only professional wildlife specialists and consulting veterinarians should be permitted to handle and treat them. A guide to cleaning and care of oiled sea otters can be found in the California Oil and Hazardous Materials Contingency Plan.
Conclusions
This status report has revealed that substantial efforts and progress have been made in oiled-wildlife research. New techniques being developed are leading to higher survival rates. Preventive measures are being devised to keep birds from entering a spill area. Wild life contingency plans are being developed and materials to handle future emergencies are being stockpiled. Basic research is being continued on the difficult problems inherent in achieving high survival levels and a rapid return to the wild, at a reasonable cost.
Much more must be done, but these pioneering efforts both within and outside of industry reflect a difficult problem yielding to the time and attention of dedicated men and women.
References
Advisory Committee on Oil Pollution of the Sea. 1972. Research unit on the rehabilitation of oiled seabirds. Committee, Dep. Zool., Univ. of Newcastle-Upon-Tyne, England, Annu. Rep. 2. 33 pp.
Atkinson-Willes, C. 1963. Wildfowl in Great Britain. Nat. Conserv. Monogr. 3. 368 pp.
Bergman, G. 1961. The migrating populations of the long-tailed duck _(Clangula hyemalis)_ and the common scoter _(Melanitta nigra)_ in the spring, 1960. Suomen Riista 14:69-74.
Blanks, D. W. 1942. Birds in the war zone. Gull 24(4):11.
Bourne, W. R. P. 1970. Special review--after the _Torrey Canyon_ disaster. Ibis 112(1):124.
Clark, R. B. 1969. Oil pollution and the conservation of seabirds. Proc. Int. Conf. on Oil Pollut. of the Sea 1968:76-112.
Clark, R. B. 1973. Impact of chronic and acute oil pollution of seabirds. Page 634 _in_ Background papers for a workshop on inputs, fates and effects of petroleum in the marine environment, Vol. 11. Ocean Board National Academy of Science, Washington, D.C.
Crummett, J. G. 1973. Bird dispersal techniques for use in oil spills. Final report. American Petroleum Institute, Washington, D.C.
Edwards, R. A. 1963. Treatment of washed up penguins. Bokmakierie 15(1):8.
Eisenhauer, D. I., and C. M. Kirkpatrick. 1977. Ecology of the emperor goose in Alaska. Wildl. Monogr. 57. 62 pp.
Fletcher, A. 1973. Why save oiled birds? University of California, College of Forestry, Berkeley. 26 pp. (Unpublished report)
Gavin, A. 1975. Wildlife of the North Slope, a five year study, 1969-73. Atlantic Richfield Co., Anchorage, Alaska. 63 pp.
Holmes, M. 1973. Oil and penguins don't mix. Natl. Geogr. Mag. 143(3):384-397.
Holmes, W. N., and J. Cronshaw. 1975. Final progress report on studies completed, 1972-75, on the effects of petroleum on marine birds. American Petroleum Institute, Washington, D.C. 77 pp. (Unpublished report)
LGL Limited. 1974. Review of current knowledge on reducing bird mortalities associated with oil spills. Petroleum Association for Conservation of the Canadian Environment Rep. 75-4. 50 pp.
Lassen, R. W. 1972. Waterbirds and the San Francisco oil spill. Proc. Cal-Nev Wildl. 1972:20-24.
Naviaux, J. L. 1972. Aftercare of oil covered birds. National Wildlife Health Foundation, Pleasant Hill, Calif. 52 pp.
Ottway, S. M. 1971. A review of world oil spillages, 1960-1971. Oil Pollut. Res. Unit, Orielton Field Centre, Pembroke, Wales.
Parslow, J. L. F. 1967. Changes in status among breeding birds in Britain and Ireland. Br. Birds 60:2-47, 97-122, 177-202.
Rowan, M. K. 1968. Oiling of marine birds in South Africa. Pages 121-124 _in_ Proc. Int. Conf. on Oil Pollut. of the Sea.
Seabird Research Unit. 1972. Advisory Committee on Oil Pollution of the Sea Research Unit on the Rehabilitation of Oiled Seabirds. Second annual report. Dep. Zool., Univ. of Newcastle-Upon-Tyne, England. 33 pp.
Smail, John. 1971. The oil spill in retrospect. Point Reyes Bird Observatory News 18:1-2.
Smith, D.C. 1975. Rehabilitating oiled aquatic birds. Pages 241-247 _in_ Proc. 1975 Conf. Prevention and Control of Oil Pollution.
Smithsonian Institution. 1971. Annual report of the Center for Short-lived Phenomena, 1970. Cambridge, Massachusetts.
Stanton, P. B. 1972. Operation rescue. American Petroleum Institute, Washington, D.C. 32 pp.
Tanis, J. J. C., and M. F. Mörzer-Bruyns. 1968. The impact of oil-pollution on seabirds in Europe. Proc. Int. Conf. on Oil Pollut. of the Sea. 1968:67-76.
CONSERVATION OF MARINE BIRDS IN OTHER LANDS
Conservation of Marine Birds in New Zealand
by
Gordon R. Williams
New Zealand Wildlife Service Department of Internal Affairs Wellington, New Zealand
Abstract
Marine species (pelagic birds and those of exposed coasts) make up about 48% of New Zealand's native avifauna, excluding stragglers and antarctic species. The biological history that has led to the present status of marine birds in this archipelago of some 700 islands is outlined, methods of conservation are briefly described, and some illustrative case histories of management programs are given. In spite of the major environmental changes that have occurred in New Zealand during 200 years of European occupation, only one marine species has become extinct, although five such endemic species are currently regarded as threatened as are a few subspecies of widely distributed forms.
New Zealand, which lies some 2,000 km southeast of Australia, has been a changing archipelago for many millions of years. It has been separated from any major landmass (first, Gondwanaland and later, Australia) for at least 80 million years.
Before the arrival of man, probably between 1,000 and 1,500 years ago, New Zealand was free of any land mammals except two species of bats, and there were few avian predators. These, among a number of other biological peculiarities, reflect the archipelago's considerable and long-standing isolation.
There are nearly 700 islands 0.5 ha or more in area in the New Zealand region; and, if North, South, and Stewart islands are regarded collectively as the mainland, about 650 of these islands lie within 50 km of the coast and 30 beyond that limit, to about 850 km offshore (Atkinson and Bell 1973). The archipelago extends from about 30° to 52°S lat. (over a distance of about 2,400 km)--that is, from the subtropical to the subAntarctic--and from about 166° to 176°W long. (Fig. 1).
Pelagic and coastal birds must obviously be an important part of the avifauna and, in fact, aside from stragglers, antarctic species, and established introduced species, they make up about 48% of the 173 in the New Zealand Checklist (Kinsky 1970). Of the 83 species I have regarded as marine, 48 (28%) are pelagic and 35 (20%) shorebirds of exposed coasts. Ten of the 48 pelagics (21%) and 12 (34%) of the 35 shorebirds are endemic.
More than a thousand years of occupation by Polynesian man with his commensal Polynesian rats _(Rattus exulans)_ and a peculiar breed of domesticated and feral dog (now extinct), did little damage to pelagic and open coast species, even though many, if not most, were used as food--especially the petrels, and particularly those belonging to the genera _Puffinus_, _Procellaria_, and _Pterodroma_. However, the Europeans, who arrived about 200 years ago, brought with them a menagerie of mammals and birds, and 33 species of each have become established and are now feral (Gibb and Flux 1973; Williams 1973). They also put into practice, on a large scale, European methods of land use that had unfortunate effects on almost the entire native avifauna. Although terrestrial, freshwater, and estuarine species suffered most, marine species suffered also. However, reduction in numbers and range rather than extinction was the rule, except locally.
Apart from habitat destruction by man and the various mammalian browsers and grazers, the most inimical agents have been black rats _(Rattus rattus)_, Norway rats _(R. norvegicus)_, feral cats, and feral pigs. One would expect the inhospitality or inaccessibility of an island to be a marine species' best protection, and so it has generally proved-the greatest losses have occurred on the two major mainland islands (North Island and South Island). Bourne (1967) suggested that Polynesians in pre-European times may have caused the extinction of numerous petrels in the Chatham Islands. There are still a few islands on which no exotic mammals occur, but modern transport, allied with human curiosity and cupidity, are stripping all but the most wild and remote of these of the protection against invasion they have had so far. Cruises by nature-hungry but sometimes environmentally illiterate tourists are beginning to be a local problem.
[Illustration: Fig. 1. New Zealand and its main offshore and outlying islands (from Atkinson and Bell 1973).]
The matter of conservation of marine species in New Zealand has stemmed mainly from the recognition of the value of certain islands as refuges for whole ecosystems, as convenient areas for study, and as arks for the rescue of the threatened species that can be successfully established on them--an often highly hazardous and uncomfortable procedure for men as well as birds.
Conservation Measures
By statute, all feral species of birds in New Zealand are automatically protected unless specifically legislated for otherwise. (About 50 of our grand total of 285 species have been so legislated for.) One fortunate consequence of this provision is that all new arrivals--vagrants or new discoveries--are also fully protected. The legislation also states that it is illegal to have in one's possession the nests, eggs, feathers, skins, or bones of any fully protected species unless one has been issued a permit for this purpose. This restriction may apply to institutions as well as to persons.
After this good start and the setting aside of conservation reserves of various kinds, active conservation measures depend on making careful and comprehensive surveys of the species and its ecosystem--often none too easy a task in the New Zealand region because of the rough seas, the relative inaccessibility of many of the important islands and their ruggedness, and the near-impenetrability of some of the vegetation types they support. Having decided that positive action is necessary, the next step is to use all available media to inform the public (local as well as national, if the island is inhabited) of the situation and the proposals for remedying it. As in most other countries, uninformed emotionalism is one of the most pervasive and serious obstacles to effective conservation because of the political pressure it can generate.
Apart from formal ecological studies, the New Zealand Wildlife Service uses three main methods to support threatened species (other than the attempts we are making to breed certain freshwater and terrestrial species in captivity):
• The translocation and founding of new colonies in promising or unmodified habitat. Such habitats are not common in New Zealand because of the ubiquity of the introduced mammalian browsers, grazers, and predators (Williams 1977).
• The destruction, or at least the reduction, of such browsers, grazers, and predators by physical, chemical, or biological methods, or combinations of these.
• The exertion of social influences to promote changes in methods of land use or in traditional harvest for food (the latter can be
## particularly important as far as the Polynesian [Maori] population is
concerned, as nowadays the taking of birds for food is predominantly a cultural rather than an economic matter).
Translocation has been a valuable technique for increasing the numbers and ranges of a few threatened terrestrial species. The very nature of most marine species, however, limits its application as far as they are concerned. Nevertheless, we have considered it worth trying for one nonmigrant wader; and no doubt it could be tried under similar circumstances elsewhere.
Convincing local experiences have shown that predator or competitor destruction is likely to be practical only on small, not-too-rugged islands, usually no larger than about 500 ha. However, special circumstances have prompted us to attempt destruction, or at least control, on much larger and more difficult islands. It is implicit that the predators or competitors are exotic, not indigenous. Recently, on those rare islands that are inhabited but still free of either black or Norway rats, we have set up permanent bait stations (at which sodium fluoroacetate--"1080"--is used as the poison) on wharves and jetties in the hope that such a precaution will, with the addition of a propaganda campaign calling for the regular fumigation of visiting vessels, prolong the charmed lives that these fortunate islands have so far enjoyed. It goes without saying that we ask that the greatest care be taken when expeditions land stores on uninhabited, rat-free islands which, if by "rat-free" we mean also free of _R. exulans_, are even rarer in our seas.
The sociolegal approach is effective only when ecosystems or communities have not been seriously modified, otherwise it is no substitute for either of the other two measures discussed.
Some Case Histories
Translocation
Last century, an endemic monotypic genus of wader--the New Zealand shore plover _(Thinornis novaeseelandiae)_--was widespread and occasionally very common around the coasts of the North and South islands and the Chatham Islands. As a result of European settlement and the accompanying predation by feral cats and rats, the species now occurs only on South East Island in the Chatham group (860 km east of the mainland), where it at present seems safe, since there are no rats on the island and it is now a reserve. However, the population numbers only about 120 individuals. Because calamities can always occur (for example, ship rats recently reached shore on three important islets off the southwest coast of Stewart Island), the Wildlife Service is anxious to spread the shore plover to other suitable islands, if they can be found. The species is not a migrant and is rather sedentary. The first translocation attempts failed, probably because mainly adult birds were used, and we are now continuing our studies of the species with the thought in mind, among others, that success may come if young birds are used instead; the question is--how young?
As is widely known, the New Zealand Wildlife Service has been remarkably successful in recent years in translocating one species of the endemic wattlebird family--the forest-dwelling saddleback _(Philesturnus carunculatus)_--to other islands than the four small ones it had been reduced to by the early 1960's; three of these islands were the ones recently invaded by ship rats, referred to above.
Predator Control
Some 25 km off the North Island's east coast lies the 3,000-ha, very rugged and forested Little Barrier Island, which has now been a reserve for the protection of flora and fauna for about 80 years. Before that, it had been almost continually occupied by Maoris since their arrival in New Zealand, and about one-third of its forest was felled or burnt, especially after European settlement of the adjoining New Zealand mainland began.
Most unusually, Little Barrier is now free of any grazing or browsing mammals, and has only the Polynesian rat (a reminder of the Maori occupation) and feral cats (a European legacy) to impair its extreme importance as a reserve. The rats have been unmolested by man because, rightly or wrongly, they are considered ineffective predators generally; however, their impact has probably been under-rated. More than half a century of trapping and hunting of cats by successive caretakers on the island has not effectively reduced that population.
Among its other important attributes, Little Barrier supports two birds endemic to New Zealand--the rare black petrel _(Procellaria parkinsoni)_, and one endemic honey-eater, the stitchbird _(Notiomystis cincta)_, which was once widespread on the North Island but is now found only on Little Barrier in moderate numbers, and apparently in no immediate danger. The impact of feral cats on stitchbirds has not been determined, but it is known that cats are seriously affecting the black petrel especially: they kill at least 90% of the chicks and some adults annually. Their impact on a locally remnant population of Cook's petrels _(P. cookii)_ is apparently less severe.
In 1968-69 the Wildlife Service, with veterinary advice and assistance, added an attempt at biological control to the campaign of poisoning ("1080" in fish was the poison and bait used), trapping, and shooting. The very specific viral disease--feline enteritis--was introduced by trapping island cats, infecting them, and then releasing them. Some estimates of the resulting mortality from the combined techniques were as high as 90%; but there has been a recovery since, and the campaign is expensive in both time and man-power. And, oddly enough, the control effort has met with some opposition. Nevertheless, another campaign is planned.
Habitat Rehabilitation by Destruction of Mammals
The Kermadecs are a group of small islands about 800 km north-northeast of the North Island. Their biological significance, insofar as this symposium is concerned, is that they are the southernmost breeding area in New Zealand seas for many elements of the Pacific tropic and subtropical marine avifauna. Unfortunately, goats were liberated on the two largest islands--Raoul (3,000 ha) and Macauley (300 ha)--almost 150 years ago and Macauley Island was burnt over; such forest cover as it had was severely damaged or destroyed, probably at about the same time. The goats were to be an emergency food supply for whalers and shipwrecked mariners. Cats, too, became feral on Raoul Island during one of its fitful periods of occupation. The New Zealand Wildlife Service, in spite of the distance and difficulties involved, has undertaken pest destruction campaigns on both islands, but I offer here only an account of the simpler, and more successful, Macauley operation.
In 1966, a 5-week expedition to this waterless and almost treeless island resulted in the shooting of what was then thought to be all of its 3,000-odd goats (a density of about 15/ha). Four years later, a follow-up expedition found and destroyed another 17 goats (a later brief inspection suggested that these were indeed the last), and rehabilitation of the island is well under way. Now that the short turf is disappearing, erosion of the soft volcanic soils is reduced. With compaction no longer occurring, it will be interesting to see what the effect will be on birds breeding on the island--six breeding species of petrels, three breeding species of terns, and other marine species.
Sociolegal Conservation
The taking of petrels and other procellariiform birds for food has always been part of the Polynesian economy and culture throughout the Pacific. In New Zealand, the practice now has only minor economic importance, but it is still an essential part of Maori culture and tradition. The most commonly taken species are the sooty shearwater _(Puffinus griseus)_ and, until recently, the gray-faced petrel _(Pterodroma macroptera)_. Although no formal study of the impact of the annual harvest of chicks on the population has yet been made, all the indications are that it is not significant. Nevertheless, the Maoris willingly accepted the limited amount of legislation that has been passed to afford the two principal exploited species at least token protection. However, on the Chatham Islands, where there is a strong tradition of taking some of the albatrosses, this tradition has persisted, even though all albatrosses are fully protected throughout New Zealand.
Enforcement of legislation in small and isolated communities is not always easy and sometimes may not be wholly politic. However, the Maoris of the Chathams have been specially informed of the conservation issues at stake, and a "gentleman's agreement" has been reached: If a planned survey shows that full protection of albatrosses in the Chathams is indeed essential, the Maoris will honor the legislation to the letter; on the other hand, if limited exploitation seems justified, the Wildlife Service has agreed that it will be allowed.
Conclusions
Insofar as conservation measures of a passive type are concerned, it is fortunate that the offshore and outlying islands not yet occupied, farmed, or set aside as reserves, are likely to remain unexploited, either because they are too remote for exploitation to be economical or because they are too inhospitable, or both. In any event, public opinion is now such that unmodified or otherwise biologically important islands not already reserved would be proclaimed as reserves if threat of exploitation arose unexpectedly, unless they were found to be major sites for oil or minerals. Even so, legislation exists that offers the possibility of protection even from this threat, and has already been used to exempt some important mainland areas from prospecting and the granting of mining rights.
It is gratifying to realize that, although some endemic marine subspecies (generally not very different from neighboring subspecies) are endangered to varying degrees, there are very few whose disappearance would result in the disappearance of the species itself from the New Zealand area. Only one endemic marine species has become extinct in recent times, the Auckland Island merganser _(Mergus australis)_ in about 1905, and only six are currently in any real danger: the Chatham Island taiko _(Pterodroma magentae)_, the black petrel, Hutton's shearwater _(Puffinus huttoni)_, the Westland black petrel (_Procellaria westlandica)_, the shore plover, and the Chatham Island oystercatcher _(Haematopus chathamensis)_. However, a list of this kind is often a matter of some controversy. Something is at present being done to help all but the first and last of these. The Chatham Island taiko had not been positively identified for about 50 years, until 1977 when this species was "rediscovered" on the main island of the Chatham group; though its numerical status is unknown, it is rare. The Chatham Island oystercatcher, although certainly "threatened" (only about 50 are known to exist), does occur on four islands, two of which are reserves. Although this species has not been
## actively studied until now, it is soon to be the subject of a full
ecological survey.
A few words about the hunting of marine species: Mutton-birding aside--that is, apart from the taking by Maoris of the young of the sooty shearwater and the gray-faced petrel--there has been no legal hunting of any marine birds in New Zealand for 35 years now, nor is there likely to be. This situation reflects the consistently increasing weight of informed public opinion in favor of, let alone scientific concern for, transoceanic migrants. The pro-hunting lobby for some species of waders, in particular the eastern bar-tailed godwit _(Limosa lapponica baueri)_, is a small one, the numbers of which decrease yearly. However, small-scale poaching occasionally occurs; it is punished when discovered.
Protection for marine species extends only to the 3-mile limit of New Zealand's territorial waters, but it would be extended further should New Zealand follow the present trend of including as territorial waters all those that cover the continental shelf or beyond. [This extension occurred in 1977; the marine fishing zone for New Zealand waters has been extended to 200 miles (360 km) around all coasts.]
Only three marine species are not afforded full protection under the Wildlife Act: two, the black-backed or Dominican gull _(Larus dominicanus)_ and the black shag _(Phalacrocorax carbo)_, are totally unprotected--the first because of its predation on some rare shorebirds during the breeding season and for its attacks on sheep and lambs at a similar time, and the second because of its depredations (seldom serious) on the introduced trout and salmon, mainly in fresh waters--the third species, the southern skua _(Stercorarius skua lonnbergi)_, may be destroyed only when it is actually attacking sheep or lambs, an occasional event confined to the Chatham Islands. Destruction of these three common species is not encouraged by the Wildlife Service except when black-backed gulls become too active among colonies of, say, the fairy tern _(Sterna nereis)_, which is very rare in New Zealand but not elsewhere in its range. Otherwise, control of the species is left in the hands of those most affected by their depredations but whose judgment is usually reasonable.
Marine birds, therefore, are generally satisfactorily protected by law or managed for conservation in New Zealand--especially when one considers the remarkable changes that have occurred in the New Zealand archipelago over the last 200 years. Although the situation could be better, it would certainly have been worse if the Wildlife Service (and other conservation organizations) had not been untiring in keeping the general public and the legislature aware of the issues at stake and seen to it that as much as possible of the necessary conservation work was done--and done before it was too late.
Acknowledgments
I thank my Wildlife Service colleagues, B. D. Bell, M. J. Imber, D. V. Merton, and C. J. R. Robertson, for valuable comments and advice on the preparation of this paper.
References
Atkinson, I. A. E., and B. D. Bell. 1973. Offshore and outlying islands. Pages 372-392 _in_ G. R. Williams, ed. The natural history of New Zealand. A. H. & A. W. Reed, Wellington.
Bourne, W. R. P. 1967. Subfossil petrel bones from the Chatham Islands. Ibis 109:1-7.
Kinsky, F. C. 1970. Annotated checklist of the birds of New Zealand. A. H. & A. W. Reed, Wellington.
Gibb, J. A., and J. E. C. Flux. 1973. Mammals. Pages 334-371 _in_ G. R. Williams, ed. The natural history of New Zealand. A. H. & A. W. Reed, Wellington.
Williams, G. R. 1973. Birds. Pages 304-333 _in_ G. R. Williams, ed. The natural history of New Zealand. A. H. & A. W. Reed, Wellington.
Williams, G. R. 1977. Marooning--a technique for saving threatened species from extinction. Int. Zoo Yearb. 17:102-106.
Marine Birds in the Danish Monarchy and Their Conservation
by
Finn Salomonsen
Chief Curator of Birds The Zoological Museum University of Copenhagen Copenhagen, Denmark
Abstract
Most species of seabirds that regularly breed in Denmark are declining, for a variety of reasons: shooting; oil pollution; toxic chemicals; reclamation of land; collecting of eggs; disturbance at breeding sites by visitors, motorboats, camping, etc.; destruction by predators; and others. On the other hand, the numbers of certain other species are increasing as a result of climatic changes (six species), protection (three species), and increase in food supply (three species of gulls). In addition to breeding birds, a total of about 3 million birds occur in Danish waters as passage migrants or winter visitors. More than half of the European winter populations of a number of marine waterfowl species winter in Denmark. Large numbers of seabirds spend the summer in Danish waters, including several hundred thousand immature gulls and just as many molting waterfowl.
The seabird fauna of the Faroe Islands is very rich, the immense number of birds being attracted by the local abundance of macroplankton and fish. The seabirds are harvested by man, formerly by fowling (capturing and shooting), now primarily by shooting. Until about 1910, more than 400,000 birds were taken annually by fowling. The Faroese game act is now very restrictive, and most seabird populations appear to be almost stable. However, a census in 1972 indicated that common murres _(Uria aalge)_ have declined by about 20% to a population of about 600,000. Shooting and snaring appear to be the primary causes of the decline; oil pollution and toxic chemicals do not seem to be contributing to the population decrease.
In Greenland seabirds provide an important source of human food; however, because of the increase in human population and in the use of guns and speedboats for hunting, and the absence of a game act, serious overshooting of seabirds is taking place. A new game act passed in 1977 should largely alleviate this overharvest. Oil pollution and toxic chemicals do not yet play an important part in influencing the number of seabirds, though offshore oil drilling is being initiated in West Greenland. A recently established gigantic national park, covering 200,000 km² of ice-free land, is the largest nature reserve in the world.
The Danish Monarchy consists of three parts far removed from each other, scattered in the North Atlantic--namely Denmark proper, the Faroe Islands, and Greenland. They differ so much from each other in climate and in bird life that they must be treated separately in this paper. The Faroes possess a provincial government and also a sort of home rule. Greenland also has a provincial government, but all statutory provisions, including acts concerning hunting or wildlife protection, must be passed by Danish authorities, usually by the Ministry of Greenland.
Insofar as seabirds are concerned, it is important that Greenland is an arctic country, whereas the Faroes and Denmark are boreal. In both Greenland and the Faroes the breeding birds are most significant, from an ecological point of view, whereas in Denmark the passage migrants and winter visitors are far more important.
There are other differences as well. In Greenland and the Faroes the seabirds mostly breed in colonies on high and steep cliffs, and the structure of these breeding places is not disturbed by man. In Denmark, on the other hand, the seabirds usually breed on glacial deposits, now forming meadows, low islets, salt marshes, etc., and these habitats have unfortunately been largely changed in the last hundred years by draining and reclamation. This practice has taken place in Denmark on a much larger scale than in most other countries and has, therefore, to a high degree diminished the life conditions of seabirds.
Seabirds in Denmark
Denmark is situated on the continental shelf of western Europe; all seas surrounding the country are shallow (less than 100 m deep), apart from the Skagerrak, north of Jutland, which is much deeper. The shallow depth, combined with the rapid flow of water between the Baltic and the North seas causes much upwelling, which forms excellent life conditions for plants and animals. It is well known that the fishery in Danish waters, especially in the North Sea, is very rich. This richness of the seas provides suitable conditions for a high diversity of seabirds and ecological types.
Seabirds regularly breeding in Denmark include five species of terns (common tern, _Sterna hirundo_; arctic tern, _S. paradisaea_; least tern, _S. albifrons_; Sandwich tern, _S. sandvicensis_; and gull-billed tern, _Gelochelidon nilota_); seven species of gulls (black-headed gull, _Larus ridibundus_; herring gull, _L. argentatus_; lesser black-backed gull, _L. fuscus_; great black-backed gull, _L. marinus_; mew gull, _L. canus_; little gull, _L. minutus_; and black-legged kittiwake, _Rissa tridactyla_); four species of geese, swans, and ducks (mute swan, _Cygnus olor_; greylag goose, _Anser anser_; common eider, _Somateria mollissima_; common merganser, _Mergus merganser_; and red-breasted merganser, _M. serrator_); three species of auks (black guillemot, _Cepphus grylle_; common murre, _Uria aalge_; and razorbill, _Alca torda_); and one species of cormorant (great cormorant, _Phalacrocorax carbo_). Shorebirds have not been included in this review. Some of the species mentioned are partly freshwater birds--for example, the black-headed gull, little gull, mute swan, greylag goose, and the two species of mergansers. The gull-billed tern forages in terrestrial habitats, but nests along the coast with the other seabirds. It is often difficult, therefore, to make a clear-cut distinction between seabirds and freshwater birds.
Among the auks, the black guillemot breeds in the Cattegat area in the huge heaps of boulders on small raised islets, or in holes (mostly formed by starlings, _Sturnus vulgaris_) on steep clayey slopes or promontories. The common murre and razorbill are restricted to the islet Graesholm in the Christiansø Archipelago, about 24 km east of Bornholm Island in the Baltic, where they breed on small cliffs of Precambrian granite rock.
The estimated number of seabirds of different species that breed in Denmark is shown in Table 1. Species like the mergansers, mute swan, and greylag goose, which breed partly or mostly in freshwater localities, are not included. Overall, the number of breeding seabirds is slowly declining, probably due to many factors which are discussed below. There are two exceptions, however, to this general decrease--the herring gull (and to a lesser degree the other big gull species) and common eider. Both species have increased during the last 50 years. Since they breed in the same habitat, usually mixed together, the eider is probably dependent on herring gulls for protection against predators. When the ducklings are fledged, the herring gull acts as a successful predator itself, but the eider nevertheless maintains a close association with herring gulls.
Table 1. _Estimated average number of breeding pairs of seabirds in Denmark, based on a census in 1970-72._ (Data for terns from Mardal 1974, and for other species from Sten Asbirk and N. O. Preuss, personal communications.)
Number of breeding Species pairs
_Sterna paradisaea_ 5,750 _S. hirundo_ 900 _S. sandvicensis_ 4,000 _S. albifrons_ 600 _Gelochelidon nilotica_ 105 _Larus marinus_ 300 _L. argentatus_ 60,000 _L. fuscus_ 2,000 _L. canus_ 28,500 _L. ridibundus_ 135,000 _L. minutus_ 25 _Rissa tridactyla_ 125 _Phalacrocorax carbo_ 600 _Somateria mollissima_ 3,800 _Cepphus grylle_ 325 _Alca torda_ 400 _Uria aalge_ 1,100 Total 243,530
More than 90% of the herring gull population breeds on small islands, and a large proportion occurs in a few large colonies. It never breeds in freshwater localities, but is exclusively found as a breeding bird in coastal habitats. The population has particularly increased in the last 5 decades, some colonies reaching their maximum size in the 1960's. Others are still expanding and occupying new breeding grounds. Today the largest colonies are found on the following islands: Saltholm, 20,000-40,000 pairs; Christiansø 9,000 pairs; Hirsholmene, 2,500 pairs; Jordsand, 1,800 pairs; Samsø, 2,000 pairs; Hjelm, 1,500 pairs; and the archipelago south of Funen, a total of 3,500 pairs in several colonies.
Attempts have been made to reduce the breeding population of herring gulls at Hirsholmene and Christiansø sanctuaries (in 1973 and 1974, respectively), to improve conditions for other nesting seabirds. In 1969 the Bird Strike Committee of the Royal Danish Airforce also initiated a program to reduce the number of herring gulls breeding on Saltholm Island, which is near the Kastrup airport in Copenhagen. Nests were sprayed with a formaldehyde oil dye, which resulted in a 33% reduction in population. In Christiansø and Hirsholmene, where the adult breeding birds were poisoned, the effect is not yet known.
The total number of seabirds occurring in the Danish waters as passage migrants and winter visitors is substantially larger than the breeding population, because Denmark is situated on a very important fall migration route for seabirds from Scandinavia, the Baltic countries, northern Russia, and northwestern Siberia. Furthermore, the shallow waters of the Danish seas (less than 10 m deep) that occupy extensive regions bordering the coasts are important feeding grounds for diving ducks. Birds frequenting the seas outside the breeding season include hundreds of thousands, or probably millions, of gulls; numerous ducks (especially diving ducks); swans and brants, _Branta bernicla_; jaegers, _Stercorarius_ spp. (four species); loons, _Gavia_ spp. (four species); grebes, _Podiceps_ spp. (four or five species); gannet, _Morus bassanus_; great cormorant; northern fulmar, _Fulmarus glacialis_; common murre; razorbill; and other species of alcids. To these should be added a number of species of various seabirds, especially gulls, tubenoses, phalaropes, and others which appear as casual or accidental visitors and which are not further mentioned in this paper.
Table 2. _Total numbers of ducks, swans, and coots recorded in Denmark during a winter census in January 1973 (based on ground counts and aerial surveys), compared with estimated flyway populations wintering in western Europe and annual bird harvest in Denmark (after Joensen 1974:23, 155, 168)._
Estimated winter Average Census, populations of the annual bag Species January 1973 Western Europe Flyway in Denmark
_Anas platyrhynchos_ 127,000 1,550,000 380,000 _A. crecca_ 500 260,000 76,000 _A. querquedula_ 11 [67] [68] _A. acuta_ 100 70,000 13,000 _A. strepera_ 5 [67] [69] _A. penelope_ 3,000 485,000 44,000 _A. clypeata_ 17 63,000 9,000 _Tadorna tadorna_ 13,000 105,000 [69] _Aythya ferina_ 7,100 235,000 5,000 _A. fuligula_ 94,700 530,000 35,000 _A. marila_ 80,900 145,000 8,000 _Clangula hyemalis_ 11,000 [67] 11,000 _Melanitta nigra_ 148,100 [67] 18,000 _M. fusca_ 6,700 [67] 9,000 _Somateria mollissima_ 450,800 [67] 136,000 _Bucephala clangula_ 67,000 142,000 25,000 _Mergus serrator_ 11,700 40,000 8,000 _M. merganser_ 23,200 75,000 6,000 _M. albellus_ 206 5,000 [69] _Cygnus olor_ 48,900 120,000 [69] _C. cygnus_ 5,700 17,000 [69] _C. bewickii_ 1,113 6,000 [69] _Fulica atra_ 142,500 [67] 70,000 Totals 1,243,252 3,848,000 853,000
A comprehensive investigation of the nonbreeding waterfowl in Danish waters was recently undertaken by the Game Biology Station Kalø (Joensen 1974). Aerial surveys of marine ducks indicate that a large percentage of the ducks that winter in European waters do so in the shallow areas of the Danish seas. A census in January 1973 indicated a total of more than 1.2 million birds (Table 2). In a number of other countrywide surveys, undertaken in all winters since 1967, usually 1.0-1.5 million birds have been recorded. Since such censuses usually give minimum numbers, and certain species-especially marine ducks--generally go unrecorded, the normal winter population (November to February) of ducks, swans, and coots in Danish waters can scarcely be less than 2 million birds (Joensen 1974:156). In Table 2, bird numbers in Denmark are compared with the estimated winter populations in western Europe, based on the investigation of Atkinson-Willes (1972). When all the winter censuses in Denmark are compared with those for Europe, as was done by Joensen (1974:156), it is evident that Danish waters support about half of all greater scaup _(Aythya marila)_, common goldeneye _(Bucephala clangula)_, red-breasted merganser, mute, whooper _(Cygnus cygnus)_, and tundra swans _(C. bewickii)_ wintering in Europe; about one-third of the population of tufted duck _(Aythya fuligula)_ and common merganser; and probably also one-third of the population of common eider and coot _(Fulica atra)_.
The wintering population of common eider is very large. According to banding records it makes up the greater part of Baltic breeding birds; however, it is not possible to calculate its percentage contribution to the total European winter population since its size is unknown in most European countries. Although most of the surface-feeding ducks disappear from Denmark waters in winter, extremely large numbers occur there during the fall migration period. For example, it has been estimated that for species like common teal _(Anas crecca)_ and wigeon _(A. penelope)_ about one-third of the West European Flyway population passes Denmark in the fall. Possibly some of the surface-feeding ducks listed in Table 2 for January 1973 were recorded in fresh water and not from the seas, but at the time the census was taken most freshwater lakes were frozen and, therefore, unavailable for water birds.
These breeding seabirds and the off-season visitors do not constitute the total population in Danish waters. Large numbers also occur in summer as nonbreeding birds; most are in two categories: (1) several hundred thousand pre-adult (up to 4-5 years of age) gulls (mostly great black-backed, herring, and lesser black-backed gulls), which feed inshore or at the coast, and (2) large concentrations of waterfowl that carry out a molt migration in Danish waters, particularly in shallow areas. Black scoter _(Melanitta nigra)_, velvet scoter _(M. fusca)_, common eider, and whooper swan are especially numerous, totaling hundreds of thousands of individuals, and probably constituting the majority of the European molting populations of these species. Less numerous, but still totaling thousands of molting birds, are sheld-duck _(Tadorna tadorna)_, common goldeneye, red-breasted merganser, and possibly some other diving ducks. About 3,000 surface-feeding ducks of various species, most of which undoubtedly are local breeding birds undergo wing molt in Danish waters. Comprehensive descriptions of the molt migration, particularly in Denmark, were published by Salomonsen (1968) and Joensen (1973_a_, 1974).
It may then be concluded that very large numbers of seabirds are found in Danish waters in all periods of the year; most feed in the inshore zone and some offshore, but none in the pelagic zone.
_Increase of Seabirds_
Seabirds are affected by several factors related to human activities, most of which pose a threat to them and will eventually reduce their numbers. Some factors, however, tend to increase bird numbers, like climatic changes which, as reported by Salomonsen (1963), have given rise to the immigration to Denmark of great cormorant (in 1938); eared grebe, _Podiceps nigricollis_ (about 1870); red-crested pochard, _Netta rufina_ (1940); common pochard, _Aythya ferina_ (about 1860); tufted duck (about 1900); and common murre (1929). They all still breed in Denmark, having more or less increased in number.
Another reason for increases of certain species is legal protection. Among protected seabirds are the sheld-duck, which has been completely protected since 1931, and particularly the mute swan, of which only 2 or 3 pairs were breeding in Denmark when the species was completely protected in 1926. Since then, mute swans have increased enormously, reaching at least 2,740 pairs in 1966 (Bloch 1971:43), of which large numbers were breeding colonially on small islets of boulders or on sand reefs off the coast (Bloch 1970:152). The gannet has also increased considerably as a fall visitor since about 1945, apparently due to protection in England and other countries.
Finally, some gull populations have increased in size because of an increase in the food supply, consisting especially of wastes from commercial fisheries and garbage dumps. In Denmark, this unnatural food source has caused an enormous increase since about 1925 in herring gulls (from less than 500 pairs to 60,000 pairs), lesser black-backed gulls (all three subspecies, _fuscus_, _intermedius_, and _graelsii_ have immigrated to Denmark), and great black-backed gulls (immigrated to Denmark in 1930). Improved waste disposal practices in recent years have not yet offset the rate of growth of these gull populations. The increase of common eiders, which also started in about 1925, is probably related to the increases in the larger gulls.
_Decrease of Seabirds_
A variety of factors tend to reduce the numbers of seabirds. The most important ones are outlined below, with comments on what has been done or what is expected to be done to reduce the impact of these activities on seabirds and protect this endangered resource.
Shooting of Seabirds
The shooting of seabirds in Denmark is considerable, because the seabirds are extraordinarily numerous, and the number of sportsmen is very large, amounting to about 135,000 (a larger number per capita than in any other country).
The Danish game statistics are excellent--well known to be much more accurate than in most other countries (see Salomonsen 1954; Strandgaard 1964). According to Danish bag records, almost one million ducks, geese, and coots (Joensen 1974:31) and about 100,000-200,000 gulls (Salomonsen 1954:125) are shot each year. The average annual bag of each species of wildfowl is given in Table 2 and the open season for each species of seabirds in Table 3. The open season for dabbling ducks is long, extending from 16 August to 31 December, which means that local birds are persecuted almost as soon as birds-of-the-year are able to fly. This has resulted in a dabbling duck breeding population that is much smaller than what the available food supply could support, and in the large-scale development of artificial rearing of mallards for later shooting. A 5-month hunting season on specialized birds like loons, grebes, and various auks is not good management practice and should be carefully reviewed.
Four other important facts about the shooting of seabirds in Denmark merit inclusion here: (1) there is no bag-limit for any species; (2) in general, all marine areas within territorial limits are open to all Danish sportsmen, and the admission is free; (3) motorboats with a maximum speed of 10 knots are allowed for shooting in the period 1 October-30 April; and (4) the shooting of seabirds is permissible from 1.5 h before sunrise to 1.5 h (in December 1 h) after sunset, whereas for most other birds shooting is prohibited between sunset and sunrise.
Shooting is a national tradition in Denmark, and the large number of sportsmen has considerable political power. Too much influence is given to the representatives of the hunters' organizations, which have the decisive force in game committees dealing with protective measures. It is difficult, therefore, to change the existing system.
Table 3. _Open hunting seasons for seabirds in Denmark, according to the Game Act of 1967. Species not given in the table are fully protected._
Hunting period and species
1 August-31 December _Anser anser_ _A. fabalis_ _A. brachyrhynchus_ _A. albifrons_ _Branta bernicla_[70] _B. canadensis_
1 August-30 April _Phalacrocorax carbo_
16 August-31 December _Anas platyrhynchos_ _A. crecca_ _A. querquedula_ _A. acuta_ _A. penelope_ _A. clypeata_
16 August-29 February _Aythya ferina_ _Fulica atra_ _Larus ridibundus_ _L. canus_
16 August-30 April _L. fuscus_ _L. argentatus_ _L. marinus_
1 October-29 February _Aythya fuligula_ _A. marila_ _Clangula hyemalis_ _Melanitta nigra_ _M. fusca_ _Somateria mollissima_ _Bucephala clangula_ _Mergus serrator_ _M. merganser_ _Gavia stellata_ _G. arctica_ _G. immer_ _Podiceps cristatus_ _Uria aalge_ _U. lomvia_ _Alca torda_
Shooting of seabirds, especially various waterfowl, is popular and intensive. The number of ducks taken by Danish sportsmen is probably in the order of 10-15% of the total kill on the West European Flyway (Joensen 1974:171). Excessive duck shooting can, in some cases, be controlled by banding in the breeding areas; the ensuing results then give rise to strong protests from the Scandinavian countries against the extensive persecution. As stated above, Denmark has (in relation to its size) the largest number of sportsmen of any nation in the world and the most intensive shooting. The number of sportsmen shooting ducks and shorebirds per 100 km² is 278 in Denmark, 28 in Sweden, 37 in Finland, 10 in Poland, 83 in Holland, 164 in Britain, and 129 in Western Germany; the number of ducks shot per 100 km² is 1,856 in Denmark, 39 in Sweden, 68 in Finland, and 129 in Western Germany (Nowak 1973). This shooting is undoubtedly of importance to dabbling duck populations, which are popular as shooting objects everywhere in Europe.
Insofar as marine ducks are concerned, it can be seen in Table 2 that appreciable numbers are shot in Denmark. The same is true for other Scandinavian countries, whereas shooting on the high seas is rather modest in most other European countries. The Danish bag undoubtedly makes up a significant proportion of the total number of marine ducks killed each year, but when the total number of ducks in European waters is considered, the shooting pressure in Denmark appears to be of only minor importance. However, the shooting, particularly when undertaken from motorboats, is so noisy and makes such a disturbance over large areas that the time for seabirds to rest and forage is significantly reduced. It must also be noted that the number of pleasure craft is steadily increasing in the present period of prosperity, and that increasing numbers of sportsmen will probably make use of the free shooting in territorial waters, since it is becoming more and more expensive to lease hunting areas.
To restrict seabird shooting, the Danish Ornithological Society has recently (1975) submitted a proposal to the Danish Government, of which the following points are relevant:
• The open season for dabbling ducks and geese should begin 15 September except for pintail _(Anas strepera)_, shoveler _(A. clypeata)_, wigeon, and pochard--species which should not be hunted until 1 October;
• the open season for all diving ducks, as well as for coot, should end 31 December;
• the open season for the great cormorant should be restricted to the period between 15 September and 31 October;
• murres, razorbill, great-crested grebe _(Podiceps cristatus)_, and all species of loon should be fully protected;
• it should be prohibited to shoot from motorboats less than 1 km from the shoreline, as well as in certain narrow sounds and fjords;
• it should be prohibited to shoot from shooting-punts less than 100 m from the shoreline;
• it should be prohibited to sell waterfowl and shorebirds shot, except for eider ducks and mallards _(Anas platyrhynchos)_; and
• no shooting should be allowed between sunset and one hour before sunrise.
Oil Pollution
Oil pollution incidents constitute one of the greatest dangers to seabird populations in Danish waters. The enormous masses of seabirds present in these waters throughout the year, combined with the fact that Danish waters contain some of the heaviest shipping traffic in the world would give rise to anxiety for oil disasters. The majority of all tanker traffic from the Atlantic and the North Sea to the Baltic passes through the Cattegat and the narrow straits of the Sound, the Great Belt, and the Little Belt, to supply a population of about 100 million people. Up to 100,000 ships pass through these waters each year, half through the Sound.
There have been severe oil pollution disasters every year since about 1935, accompanied by enormous mortalities of seabirds, particularly marine ducks. The Danish Game Biology Station, which has studied these disasters (Joensen 1972_a_, 1972_b_, 1973_b_), has noticed that the number of seabirds involved has increased in recent years, in spite of increased control by Danish authorities.
Unfortunately, it appears that small amounts of oil in the sea, originating from cleaning the tanks of vessels, or from the release of a few tons of oil, are enough to create mass mortality of seabirds when large concentrations of birds are present in the vicinity. Such incidents have passed unnoticed in spite of control measures. In no case has the source of the pollution been traced (Joensen 1972_b_:27). There has not yet been a real "oil disaster" in the Danish waters similar to the _Torrey Canyon_ catastrophe. If such a disaster takes place, the destruction of seabirds will be enormous and immeasurable.
Table 4. _Species composition of 8,304 birds killed by oil and examined in connection with five pollution disasters in the Cattegat, 1969-71._ (After Joensen 1972:12.)
Oil incident no.
Species 1 2 3 4 5 Totals
_Gavia stellata_ 1 9 1 4 15 _G. arctica_ 2 2 4 8 16 _Gavia sp._ 4 1 5 _Podiceps grisegena_ 4 1 8 8 21 _P. cristatus_ 1 1 _Phalacrocorax carbo_ 20 20 _Anas platyrhynchos_ 2 2 4 _A. clypeata_ 2 2 _Aythya marila_ 6 2 8 _Clangula hyemalis_ 35 2 26 6 4 73 _Melanitta nigra_ 387 241 521 262 77 1,488 _M. fusca_ 197 33 417 223 119 989 _Somateria mollissima_ 1,683 1,081 947 1,713 19 5,443 _Bucephala clangula_ 3 3 13 9 28 _Mergus serrator_ 48 28 28 2 106 _Cygnus olor_ 10 17 1 28 _C. Cygnus_ 1 1 _Fulica atra_ 1 1 2 5 9 _Larus sp._ 13 13 _Alca torda_ 1 12 1 14 _Uria aalge_ 1 1 _Cepphus grylle_ 1 2 16 19
Total birds examined 2,380 1,362 1,996 2,324 242 8,304
Estimated minimum number of birds killed 10,000 5,000 12,000 15,000 1,500 43,500
Percent of total birds contributed by three species[71] 95.3 99.5 94.4 94.6 88.8 95.4
As a result of five of the major oil pollution incidents in the Cattegat from 1969-71, a total of 43,500 birds were killed, of which 8,304 were examined and enumerated (Table 4). Altogether, 21 or 22 species were involved, but 95% of all birds examined were diving ducks: common eider and black and velvet scoters. At present, it has not been possible to identify any decrease in the number of these ducks in Danish waters due to oil pollution. However, if these disasters continue, it can be expected that duck populations of northern Europe and the Baltic area will be severely reduced, and that an overall decline will take place from which the birds may not be able to recover.
A particularly disastrous year was 1972, when large numbers of ducks were killed as a result of rather small oil spills. A tanker disaster in March 1972 off the eastern coast of Jutland, in the northern Cattegat, and another in December 1972 in the Danish Waddensea, both took place in areas critical to major concentrations of sea ducks. A total of more than 60,000 birds were killed, of which about 95% consisted of the same three species of diving ducks mentioned above. These tragic events represent a further increase in the annual mortality of birds caused by oil, and there is reason to believe that a critical upper limit is rapidly being approached.
It appears, however, that the measures taken by pollution control and naval authorities have greatly improved in recent years. In January 1973, when a Polish merchant vessel collided with a Swedish tanker in the Sound, about 300 tons of heavy fuel oil were released into the sea. Several Danish and Swedish ships working in cooperation succeeded in dispersing the oil, and no serious effect on seabird populations took place (Joensen 1973_b_:118). It seems that the best way of cleaning up such oil disasters is through a mechanical removal of the oil, but this is a very expensive and difficult procedure.
Pollution by Toxic Chemicals
Chemical pollution is probably the most ominous threat to seabirds at present. Since all toxic chemicals used in agriculture ultimately end up in the sea, and many large factories release their industrial wastes directly into the sea, the effects of this pollution on marine organisms is attracting a growing interest. Many students have worked on these problems, and the results that concern birds were summarized by Bourne (1972:205). It is known that organochlorine residues have been found in seabirds in all the oceans of the world, including Antarctic waters and Arctic seas (Bogan and Bourne 1972:358). The chemicals most often found in birds are DDE (a metabolite of DDT) and PCB's (polychlorinated biphenyls), a mixture of related chemical compounds often originating from industrial wastes. In addition, some mercury will always be found, sometimes in increased concentrations. The present restrictions on the use of DDT and PCB in Denmark have not yet resulted in a corresponding decrease in the amount of these pesticides in birds.
It is well known that marine pollution reaches a peak in the Baltic. This high level of pollution is reflected in seabirds. For example, analyses have shown that eggs from the colony of common murres on Christiansø in the Baltic contain about 100 times as much DDE and 50 times as much PCB as eggs of murres from the Faroe Islands in the Atlantic Ocean (Dyck 1975).
A similar difference exists in the mercury content in birds examined in the two areas. Feathers of a large sample of black guillemots and murres from the Cattegat and the Baltic had higher mercury levels than those from the Faroe Islands and Greenland. It is interesting that this difference existed over a hundred years ago, as evidenced by the analysis of feathers in museum specimens. The Baltic populations of both species show very significant increases in the mercury content in 1965-70, as compared with the values earlier in this century. Since 1970 there has been a sharp decrease in mercury content, and in 1973 the level was almost as low as it was early in the century. These results indicate that the strict control of mercury discharges enforced in Sweden has resulted in a quick recovery of nearly normal conditions in the Baltic (Somer and Appelquist 1974). However, recent studies by Koeman et al. (1975:286) appear to show that mercury does not accumulate to the same extent in seabirds as it does in seals.
High concentrations of chlorinated hydrocarbon residues accumulate in carnivorous birds and upset the normal breeding behavior by making the eggshells too thin and fragile to survive (Peakall 1970:73; Mueller and Leach 1974:289). In Denmark, shells of herring gull eggs from the Baltic population were thinner, lighter, and more heavily contaminated with DDE and PCB than were shells of eggs from other colonies (Jørgensen and Kraul 1974:173). This further emphasizes the pollution of the Baltic Sea.
Massive mortalities of common murres, such as the one reported in the Irish Sea in the fall of 1969 which was apparently caused partly by malnutrition and PCB poisoning (Parslow and Jefferies 1973:87), are unknown in Danish waters.
It should be added that the pollution of seawater with cadmium, so very dangerous for man, has been high in recent years owing to the increased use of this element in industry, but no analysis of its importance for seabirds in Danish waters has yet been made.
It should also be mentioned that pollution of fresh water in lagoons or lakes near the sea can often cause serious declines in numbers of certain seabirds. This is well illustrated by recent events in the sanctuary Nakskov Indrefjord on the island of Lolland. This landlocked fjord once supported numerous breeding populations of ducks, grebes, and terns, but in recent years a number of species (e.g., eared grebe; common teal; garganey, _Anas querquedula_; pintail; and black tern, _Chlidonias nigra_) have failed to breed and practically all other species have declined in numbers. The main reason for these changes is a severe pollution from the admission of raw sewage from tributaries (Bloch et al. 1972). After several outbreaks of botulism in recent years, procedures to improve conditions are now being developed.
Other Threats to Seabirds
The most dangerous threats to seabirds are those discussed above. Authorities are aware of these dangers and attempts are being made to improve conditions. Some results have been achieved in the combat against oil pollution, and the control of shooting is reaching an acceptable level. Game management agencies in Denmark and other Scandinavian countries (Norway, Sweden, and Finland) are cooperating on the request of the parliamentary body of the Nordic Council. If game biologists in these countries could agree on proposed changes in the game acts, owing to the marked decline of a number of bird species, the parliamentary basis for such a legal step would be absolutely certain.
However, it must be admitted that the impact of man on the environment is enormous, especially in a country like Denmark, which possesses no raw materials, and where agriculture has transformed the whole country. In such a country, the birds have to "face the music," and by this sharing of resources with man, they will inevitably decrease in number. It is the responsibility of biologists and politicians, without emotional biases, to find the balance between the requirements of the two spheres of interest.
Many other dangers that threaten seabirds, some of which are unrelated to human activities, are listed here.
• Land reclamation.--Reclamation of land has reduced extensive areas of shallow water, lagoons, marsh land, etc., from seabirds for foraging or breeding places. Draining and diking of coastlands, estuaries, and saltings have had the same effect. This activity is now almost stopped, as these projects are no longer subsidized by the government.
• Egg-collecting.--According to the present game act, collecting gull eggs is permitted until 24 May. This creates much disturbance on the breeding grounds, and eggs of terns and shorebirds are also taken. This practice should be halted. The "Bird Island Group" of the Danish Ornithological Society, in a symposium in 1972, prepared some rules for the protection of seabirds, among which is a proposal to stop egg-collecting.
• Common property.--The Nature Conservancy Act regards all land not fenced in, even small uninhabited islets, as common property. People have free access to such areas with the result that seabirds breeding in colonies, or separately on islands, are disturbed by visitors arriving by boat. At the same time, noisy motorboats, bathing parties, or camping visitors frighten the birds, making successful breeding almost impossible. Even ornithologists, bird-banding teams, and bird photographers add to the destruction. The "Bird Island Group" of the Danish Ornithological Society has proposed a general prohibition against visitors on important bird islands from 1 March to 15 July to protect the breeding seabirds.
• Destruction by predators.--Fox, ermine, and stone-marten do not play an essential role. Rats are more important, even on small islands, and have caused destruction of tern and gull colonies. Rat numbers do not decline until a severe winter with much ice occurs, or until high tide kills them all. Large gulls also cause a great deal of destruction, but crows and magpies are unimportant as predators in seabird colonies. Numbers of nonbreeding mute swans or greylag geese may sometimes be a nuisance, trampling eggs and nestlings in seabird colonies.
• Forestry practices.--The prevailing practice of the forestry industry in Denmark of not preserving old trees with holes has considerably diminished the breeding habitat of hole-nesting species like the common merganser. Artificial nest-boxes have now been established in several areas.
• Sea conditions.--During high water, or rough sea, salt water may flood colonies of breeding seabirds nesting on low islets, often reducing the production of young.
• Aircraft disturbance.--Disturbances are also caused by noise from jet aircraft flying low, especially in military training areas where air traffic may be heavy.
• Commercial fisheries.--Modern commercial fisheries are depleting so-called industrially important fish stocks such as sand eels _(Ammodytes)_, herrings, and other small fish over large areas of the sea for the production of fish meal. This fishing has undoubtedly been the main reason for the decline in the number of terns--especially sandwich terns which depend on these small fish species for food.
• Unknown factors at sea.--Large numbers of pelagic seabirds,
## particularly fulmars, kittiwakes, and gannets, are washed up on
the western coast of Jutland in certain years (e.g., 1959, Joensen 1961:212). These birds died at sea, for unknown reasons, and apparently as a result of food shortages or oil pollution.
_Conservation_
The threats to seabirds mentioned above are all well known to conservationists, who are attempting to reduce the impact of these factors on seabirds where possible. Insofar as legal protection is concerned, it must be admitted that there are no marine sanctuaries in Denmark, although several discussions have taken place reviewing the possibility of establishing some in critical areas. There are, however, a number of sanctuaries on islands where seabirds breed. In the Sanctuary Act of 1936 these areas were called "Scientific Reserves" because they were the site of scientific investigations of bird life. All admission was forbidden, at least during the breeding season, and all shooting was prohibited, with few exceptions. These sanctuaries were administered by the government's Nature Conservancy.
The following Scientific Reserves are important for seabirds: Hirsholmene Islands (in Cattegat off Frederikshavn), Knotterne Islands (small islets east of Laesø Island), Vejlerne (diked in, landlocked fjords, densely covered with vegetation, at the Lim Fjord), Tipperne Peninsula and Klaegbanken Island (in Ringkøbing Fjord, western Jutland), Varsø Island (Horsens Fjord, eastern Jutland), and Græholm Island (Christiansø Archipelago, in the Baltic off Bornholm). A detailed description of these sites and their erection, bird life, and ornithological value was given by Salomonsen (1945). More recently, two additional Scientific Reserves have been established: Aegholm Islet (south of Sealand), and Hesselø Island in the southern part of Cattegat.
In addition to these scientific sanctuaries, there are game reserves and governmental forest reserves in Denmark. The game reserves are administered by the Ministry of Agriculture, which is also responsible for hunting legislation. The purpose of game reserves is to support and protect the stock of game, which includes migrating birds. Shooting is usually prohibited, but a restricted shooting season is allowed at some reserves. More than 50 game reserves are now present and functioning. Regulations differ widely from reserve to reserve, but entry to some of them is not allowed in the breeding season. Many reserves are important for breeding or migrating waterfowl and some seabirds. In fact, a total of 26 game reserves contain seabirds, the most important of which are the following: Ulvedybet (landlocked fjord at the Lim Fjord), Hjarbaek Fjord (landlocked fjord with brackish water at the Lim Fjord), Felsted Kog (landlocked fjord at Nissum Fjord), Jordsand (large stretches, almost 11,000 ha, of the Danish Waddensea), Stavns Fjord (at Samsø Island), Esrum Lake (in northern Sealand), and Kalvebod Beach (at Amager Island, near Copenhagen).
In the Nature Conservancy Act of 1969, differences between scientific and game reserves were abolished, although regulatory provisions that were in force for the scientific sanctuaries were maintained. Unfortunately, the amalgamation of the two types of reserve has given more power to the hunters' associations, which constitute the majority of the administrative body of the reserves, the so-called Game Commission ("Vildtnævnet"). However, any change in status of the original scientific reserves will not be tolerated by conservationists and other environmental groups in Denmark.
The Faroe Islands
The number of seabirds in the Faroe Islands is greater than in any other region of the North Atlantic, and is closely related to the extraordinary richness of the plankton. The high phytoplankton production is due to a strong vertical mixing of the water in the northeast Atlantic, especially at the slopes of the submarine ridges, where both tidal currents and oceanic currents are usually strong. The resulting upwelling enriches the upper layers of water with large quantities of nutrient salts for the phytoplankton, and this, in turn, produces a teeming life of macroplankton and fish on which the seabirds are dependent (Salomonsen 1955).
The enormous seabird population of the Faroes is apparent from the first description of the islands, "De mensura orbis terrae," a document written in the year 825 by the Irish monk Dicuilus, who described the most characteristic feature of the Faroes as being the fact that "the islands were full of various kinds of marine birds." This richness has remained to the present, and has provided an important source of food for the resident human population, particularly in former times. There are few, if any, countries in the world in which wild-fowling and other exploitations of birdlife have played such a major role as in the Faroes. A number of elaborate and varied bird-catching methods were invented, and these have remained essentially the same for at least the last 500 years. Bird-fowling at great heights on precipitous sea-cliffs was a dangerous venture, and each year lives were lost. The main thing, however, was that food obtained from fowling meant life and death for local inhabitants and so was undertaken in such a well-balanced way that the seabird populations did not decrease or disappear. Some fowling still takes place, but on a reduced scale, since most men are now engaged in the fishery during the summer. Shooting is now of much greater importance than in former times.
The Faroese game acts (from 1897, 1928, and 1954) are very severe and show a broad consideration for birdlife. Practically all terrestrial birds, including shorebirds, are protected, and existing regulations permit people to catch or shoot only common murres, razorbills, puffins, shags _(Phalacrocorax aristotelis)_, fulmars, gannets, parasitic jaegers _(Stercorarius parasiticus)_, and gulls, as well as a few "pest" species like crows _(Corvus corone)_ and ravens _(C. corax)_. The legal right of fowling on a "fowling cliff" belongs to the registered owner of the land on which the cliff is situated. There are some sound restrictive laws for these cliffs. For example, shooting within 3.2 km of any seabird colony is prohibited.
Table 5. _Number of seabirds caught by fowling each year in the Faroe Islands in the early 1900's._ (From Salomonsen 1935.)
-------------------------------------- Number of birds Species caught per year -------------------------------------- _Uria aalge_ 60,000 _Fratercula arctica_ 270,000 _Puffinus puffinus_ 1,500 _Fulmarus glacialis_ 80,000 _Morus bassanus_ 1,300 Total 412,800 --------------------------------------
The annual number of seabirds caught by fowling in the early 1900's (summarized in Table 5) were reported in Salomonsen (1935). This large harvest of birds, taken by fowling year after year for centuries, did not appear to influence the seabird populations, as bird numbers remained stable. However, in recent years, shooting and a special form of snaring of murres have increased dramatically and seem to have endangered the murre population. The annual number of murres killed is estimated to be about 120,000, of which 70,000 are snared and at least 50,000 shot (estimates of birds shot range from 50,000 to 100,000). This total is almost double the number of birds caught during fowling, and because of an apparent decline in murre numbers the provincial government decided to investigate the matter, and in 1972 the Danish Ornithological Society agreed to conduct the study. Figures from the 1972 census of murres (Table 6) show that almost 600,000 birds were counted, from which an estimate of more than 393,000 breeding pairs was calculated (Dyck and Meltofte 1975). In spite of this large number, Dyck and Meltofte (1975) concluded that the Faroese murre population has declined by about 20% during the last 10-15 years. Investigations are under way to monitor further changes in murre numbers, and to determine the trend, and whether reductions in shooting and snaring are necessary to maintain the population.
Oil pollution is practically unknown in Faroese waters, but since drilling for oil will probably take place in the near future, the importance of oil to birds in this region may change. Toxic chemicals do not appear to be involved in the decline in murres. Investigations of concentrations of chemical pollutants in their eggs show that levels of DDE (mean 1.1 ppm), PCB (mean 2.0 ppm), and mercury (mean 0.2 ppm) (Dyck and Meltofte 1975) are relatively low and unlikely to affect reproduction (Dyck and Meltofte 1975). Levels are much smaller than those found in seabirds in Britain, the Baltic, or in albatrosses in the Pacific (Fisher 1973).
Table 6. _Colonies of the common murre,_ Uria aalge, _on the Faroe Islands, based on a census conducted in 1972._ (After Dyck and Meltofte 1975.)
---------------------------------------------- Number of birds Number of Colony observed pairs[72] ---------------------------------------------- Suderoy 73,945 49,500 Lítla Dímun 13,220 8,800 Stóra Dímun 68,050 45,600 Sandoy 101,710 68,100 Hestur 17,290 11,600 Mykines 14,500 9,700 Vágar 4,224 2,800 Streymoy 27,214 18,200 Eysturoy 10,520 7,000 Kalsoy 14,150 9,500 Vidoy 5,980 4,000 Fugloy 22,730 15,200 ------- ------- Totals 587,333 393,200[72] ----------------------------------------------
Greenland
Greenland, which has an area of 2,175,600 km² and extends for a distance of 2,670 km from the northernmost to the southernmost point of the country, is almost a continent by itself. The range of the different species of seabirds, therefore, is greatly varied, and it is necessary to classify them according to the relation between their distributions and the marine zones. A description of the zones of the marine environment in the North Atlantic was given by Salomonsen (1965), and the breeding distributions of seabirds in Greenland based on this system are given in Table 7. The terrestrial area of southernmost West Greenland belongs to the subarctic zone of the boreal province, and one boreal bird species, the black-headed gull, has bred there in recent years. It is, however, as much a freshwater bird as a marine one.
Table 7. _Distributions of seabirds breeding in Greenland in relation to marine zones._
Marine zone and species[73]
Boreo-panarctic _Fulmarus glacialis_ _Somateria mollissima_ _Stercorarius parasiticus_ _Rissa tridactyla_ _Sterna paradisaea_ _Cepphus grylle_ _Fratercula arctica_ Panarctic _Larus hyperboreus_ _Uria lomvia_ _Clangula hyemalis_ _Gavia stellata_ High arctic _Somateria spectabilis_ _Branta bernicla_ _(hrota)_ _Stercorarius longicaudus_ _Xema sabini_ _Larus thayeri_ _Pagophila eburnea_ _Cepphus grylle_ (_mandti_ group) _Plautus alle_ _Fratercula arctica_ _(naumanni)_ _Phalaropus fulicarius_ Low arctic _Larus glaucoides_ _Phalaropus lobatus_ Boreo low arctic _Mergus serrator_ _Phalacrocorax carbo_ _(carbo)_ _Larus marinus_ _Alca torda_ _Uria aalge_ _Cepphus grylle_ (_grylle_ group) _Fratercula arctica_ _(arctica)_ Boreal _Larus ridibundus_
[Illustration: Fig. 1. Breeding range in Greenland of four boreo-panarctic seabirds, _Fulmarus glacialis_, _Somateria mollissima_, _Rissa tridactyla_, and _Fratercula arctica_.]
[Illustration: Fig. 2. Breeding range in Greenland of three boreo-panarctic seabirds, _Sterna paradisaea_, _Cepphus grylle_, and _Stercorarius parasiticus_, and one low arctic species, _Phalaropus lobatus_.]
[Illustration: Fig. 3. Breeding range in Greenland of three panarctic seabirds, _Uria lomvia_, _Larus hyperboreus_, and _Clangula hyemalis_, and one high arctic species, _Stercorarius longicaudus_.]
[Illustration: Fig. 4. Breeding range in Greenland of three boreo-low arctic seabirds, _Mergus serrator_, _Larus marinus_, and _Phalacrocorax carbo_, and one high arctic species, _Plautus alle_.]
The widely differing ranges of Greenland seabirds are shown in Figs. 1-4 and are based on my new and previously unpublished data. The borderline between the high arctic and low arctic zones is situated in Melville Bay on the west coast, and just south of Scoresby Sound on the east coast; the innermost parts of Scoresby Sound belong to the low arctic zone.
In the low arctic Pacific region the number of seabirds is said to be about 51 million in summer and 8 million in winter (Sowl and Bartonek 1974). No similar estimate is available for low arctic West Greenland, but I suggest that it is much lower in summer and slightly higher in winter.
The human population of Greenland, now numbering about 50,000 individuals, is restricted to the seashore, where all cities and minor outposts are situated. Although shooting seabirds is an ancient tradition in Greenland, the true land-birds, which are few in number, are usually left alone. Seabirds collected by shooting provide an important source of food that the Greenlanders could not do without. Since special shooting and hunting regulations have not been developed in Greenland, these activities often resemble a sort of slaughter rather than true hunting. There is no game act in Greenland, and practically all birds can be shot. This condition is similar to that in Canada, where according to Section 5(7) of the Migratory Birds Regulations (Canadian Wildlife Service, Ottawa 1973) "an Indian or Inuk may at any time, without a permit, take auks, auklets, guillemots, murres, puffins and scoters and their eggs for human food and clothing." Much the same sort of hunting privileges exist for native peoples of Alaska. What is still worse, however, is the enormous illegal shooting of ducks, geese, swans, and cranes that is known to take place in arctic North America, but is largely ignored by police and game authorities. Bartonek et al. (1971) described this situation very well for Alaska. In Greenland, it is not possible any more to distinguish between "native Eskimos" and Greenlanders (including Danes working in the country), but the attitude toward animals among the inhabitants is the same as it has always been--a food source to hunt and kill.
With a rapidly growing human population, and a readily available supply of guns and speedboats for hunting, the whole natural ecosystem is beginning to break down, and it cannot be permitted to continue. The provincial government is aware of this fact, and various legal enactments have been issued from both the government and the local magistrates. However, since the size of the police force (mostly Greenlanders) is small, it is of little help for the preservation of wildlife, and sometimes even the policemen themselves do not know the local ordinances. The result has been that seabirds, previously profusely flourishing, have considerably decreased in number in West Greenland.
I have previously described the shooting and hunting of seabirds in Greenland and the statutory provisions issued to protect them (see Salomonsen 1970). At present, the following seabirds and their eggs are totally protected: whooper swan; common puffin, _Fratercula arctica_; and harlequin duck, _Histrionicus histrionicus_. Some other species have a closed season or are protected in certain parts of the country: snow goose, _Anser caerulescens_; common eider; king eider, _Somateria spectabilis_; great cormorant; dovekie, _Plautus alle_; black guillemot; and thick-billed murre, _Uria lomvia_. Furthermore, all catching and hunting of birds within 2 km of breeding colonies of murres and kittiwakes is prohibited. Bird sanctuaries where hunting, catching, and collecting of eggs and down are prohibited are Avsigsut, Nunatsiaq, and Satuarssunguit islands, which are scattered in Disko Bay, and Tasiussarssuaq Fjord (the inner part of Arfersiorfik Fjord, south of Egedesminde).
However, the Greenland Provincial Council has been alarmed by the serious decline in the numbers of seabirds due to increases in human persecution, and it has decided to introduce a game law similar to those in Denmark and other European countries. The preparation of this legislation was left to me, and a draft of this Greenland game act has been issued (Salomonsen 1974); the new law was passed in parliament in 1977 and went into force on 1 January 1978.
It is not possible to review in detail the different parts of the new law, but certain important points should be mentioned. In northern parts of West Greenland (north of Egedesminde) the sea is ice-covered for 7-8 months a year, and seabird hunting is therefore not possible outside the breeding season. Because of this, it was necessary to allow some hunting of murres, eiders, and immature gulls during the breeding period, but away from nesting locations. Consumption of seabirds is to be limited to local residents, and sales to canneries for shipment to other cities is to cease. Previously, canneries in northwest Greenland exported large numbers of thick-billed murres to South Greenland--e.g., 25,606 birds in 1971; and 30,029 in 1972 (Anonymous 1974:64). This marketing of murres will end.
Other parts of the proposal important for seabirds include:
• A general closed season extending from 15 June to 15 August.
• Prohibition of shooting at breeding colonies of seabirds, as is in force at present (cf. above).
• Eggs of terns and gulls can be collected for food in southwest Greenland to 1 July, and in northwest Greenland to 10 July; fulmar and murre eggs can also be collected in northwest Greenland.
• Each hunter is allowed to shoot or catch 50 birds per day, but the entire bag must be used for human consumption.
• All shooting from speedboats, aircraft, and motor vehicles is prohibited.
• Catching flightless common eiders, king eiders, and oldsquaws _(Clangula hyemalis)_ is prohibited.
• Practically all seabirds and shorebirds can be shot; all other birds (except rock ptarmigan and raven) are totally protected.
The principles of this radical new act must be taught to the population by all possible means of communication, including radio, public meetings, schools, etc.
* * * * *
Another matter of great concern to seabirds in Greenland is the Atlantic salmon fishery off the west coast by Danish, Greenlandic and foreign fishermen. It is well known that many birds are killed in the fishing gear, and a serious political controversy has arisen, especially between the governments of the United States and Denmark. The fact that a large number of thick-billed murres were drowned in salmon gill nets during their southward swimming migration along the Greenland coast was significant. In a resolution sent by the XV World Conference of the International Council for Bird Preservation in Texel to the Danish Government, it was stated that the annual incidental drowning of murres probably involved about 250,000 individuals--a figure exceeding the reproductive capacity of the species. This estimate was doubted by Danish fishery biologists, but recent investigations carried out by the Canadian Wildlife Service and the Fisheries Research Board of Canada have shown that the figure is even greater, and that the total kill amounts to about half a million murres annually (Tull et al. 1972).
Because of this mortality of murres, an agreement was reached between the American and Danish governments, namely that:
From 1 January 1976, all salmon fisheries outside the 12-mile boundary shall totally stop. In the years 1972-75 the fishery carried out by Danish and Faroese fishermen shall be reduced gradually from 800 to 300 tons of fish, and shall terminate on 31 December 1975. The fish quota by Greenland fishermen must amount to no more than 1,100 tons annually, but from 1976 onwards, the fishery shall be restricted to areas within the 12-mile limit.
This agreement, which has drastically reduced the number of murres caught, was discussed at a meeting of the International Committee of North Atlantic Fisheries in May 1972, and was ratified by the countries involved in July 1972.
Oil pollution has never occurred in Greenland, but concessions for offshore oil drilling along the West Greenland coast have just been granted by the Danish Government, and this new development gives rise for concern. However, it is clearly stated in the concession that the Ministry for Greenland can lay down rules for protection against oil pollution and other damage to human or animal life, and can adopt measures to fight pollution which has already taken place (section 5(9)). It is up to the concessionary to oversee industrial developments in the area and see that marine pollution is avoided (section 11).
Toxic chemicals have been found in Greenland seabirds, as everywhere else in the world, but it must be emphasized that no pesticides whatsoever are in use in Greenland itself. Investigations by Somer and Appelquist (1974) indicated that the mercury content in black guillemots in Greenland has doubled over the last 20 years, and has now reached 2 ppm, which is, however, a relatively low figure. Levels of DDE, PCB, and aldrin in Greenland birds were investigated by Braestrup et al. (1974). Common eider, king eider, harlequin duck, and oldsquaw, as well as thick-billed murre and great cormorant, were examined; all were found to be contaminated with pesticides, although to varying degrees. Highest concentrations occurred in the cormorant, which contained 6.5-15 ppm of DDE and 14.1-46.7 ppm of PCB. These specific differences appear to show that the pesticide level in the different species of seabirds is influenced more by the position of the bird in the food chain than by its migratory habits.
And finally, I wish to mention a more happy event. On 9 May 1974 a new law of nature protection in Greenland was passed by the Danish Parliament. According to this law, a National Park is to be established covering almost the entire northeast and north regions of Greenland, from the Thule District in northern West Greenland around the entire north coast of Greenland and south along the east coast to the northern inner parts of Scoresby Sound. All hunting, fishing, egg-collecting, and disturbances to the environment are forbidden in this enormous area. This is by far the greatest National Park in the world, covering about 800,000 km². Of this total area, the greater part is a lifeless icecap, to be sure, but about 200,000 km² is ice-free land and suitable habitat for numerous high-arctic birds.
References
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Bartonek, J. C., J. G. King, and H. K. Nelson. 1971. Problems confronting migratory birds in Alaska. Trans. N. Am. Wildl. Nat. Resour. Conf. 36:345-361.
Bloch, D. 1970. The mute swan _(Cygnus olor)_ breeding in colony in Denmark. [Danish with English summary.] Dansk Ornith. Foren. Tidsskr. 64:152-162.
Bloch, D. 1971. Ynglebestanden af knopsvane _(Cygnus olor)_ i Danmark 1966. Danske Vildtundersøgelser 16. 47 pp.
Bloch, D., C. H. Ovesen, B. H. Fenger, J. Jensen, and J. Pedersen. 1972. Vildtreservatet Nakskov Indrefjord. Resume af biologiske, kemiske og fysiske underseøgelser i 1970-1971. Vildtbiologisk Station, Kalø, Rønde. 15 pp.
Bogan, J. A., and W. R. P. Bourne. 1972. Organochlorine levels in Atlantic seabirds. Nature (Lond.) 240(5380):358.
Bourne, W. R. P. 1972. Threats to seabirds. Int. Counc. Bird Preserv. Bull. 9:200-218.
Braestrup, L., J. Clausen, and O. Berg. 1974. DDE, PCB and aldrin levels in arctic birds of Greenland. Bull. Environ. Contam. Toxicol. 11(4):326-332.
Dyck, J. 1975. Miljøgifte i danske fugle. Panda-Nyt. Verdensnaturfonden 1975(1):11-13.
Dyck, J., and H. Meltofte. 1975. The guillemot _Uria aalge_ population of the Faeroes 1972. Dansk Ornith. Foren. Tidsskr. 69:55-64.
Fisher, H. I. 1973. Pollutants in North Pacific albatrosses. Pacific Sci. 27(3):220-225.
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Joensen, A. H. 1972_a_. Oil pollution and seabirds in Denmark 1935-1968. Dan. Rev. Game Biol. 6(8):1-24.
Joensen, A. H. 1972_b_. Studies on oil pollution and seabirds in Denmark 1968-1971. Dan. Rev. Game Biol. 6(9):1-32.
Joensen, A. H. 1973_a_. Moult migration and wing-feather moult of seaducks in Denmark. Dan. Rev. Game Biol. 8(4):1-42.
Joensen, A. H. 1973_b_. Danish seabird disasters in 1972. Mar. Pollut. Bull. 4(8):117-118.
Joensen, A. H. 1974. Waterfowl populations in Denmark 1965-1973. A survey of the non-breeding populations of ducks, swans and coot and their shooting utilization. Dan. Rev. Game Biol. 9(1):1-206.
Jørgensen, O. H., and I. Kraul. 1974. Eggshell parameters, and residues of PCB and DDE in eggs from Danish herring gulls, _Larus a. argentatus_. Ornis Scand. 5(2):173-179.
Koeman, J. H., W. S. M. van de Ven, J. J. M. de Goejj, P. S. Tjioe, and J. L. van Haaften. 1975. Mercury and selenium in marine mammals and birds. Sci. Total Environ. 3:279-287.
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Mueller, W. J., and R. M. Leach, Jr. 1974. Effects of chemicals on egg shell formation. Annu. Rev. Pharmacol. 14:289-303.
Nowak, E. 1973. Hunting kill statistics investigation. Int. Waterfowl Res. Bur. Bull. 35:26-30.
Parslow, J. L. F., and D. J. Jefferies. 1973. Relationship between organochlorine residues in livers and whole bodies of guillemots. Environ. Pollut. 5:87-101.
Peakall, D. B. 1970. Pesticides and the reproduction of birds. Sci. Am. 222(4):72-78.
Salomonsen, F. 1935. Ayes. _In_ R. Spärck, ed. Zoology of the Faroes 3(pt. 2) (lxiv):269 + 6 suppl. A. F. Høst, Copenhagen.
Salomonsen, F. 1945. De videnskabelige reservater i Danmark og deres Fugleliv. Fauna och Flora 40:250-261.
Salomonsen, F. 1954. The Danish game-statistics. [Danish with English summary.] Dansk Ornith. Foren. Tidsskr. 48:123-126.
Salomonsen, F. 1955. The food production in the sea and the annual cycle of Faeroese marine birds. Oikos 6(1):92-100.
Salomonsen, F. 1963. Oversight over Danmarks fugle. [With explanatory notes in English.] Munksgaard, Copenhagen. 156 pp.
Salomonsen, F. 1965. The geographical variation of the fulmar _(Fulmarus glacialis)_ and the zones of marine environment in the North Atlantic. Auk 82:327-355.
Salomonsen, F. 1968. The moult migration. Wildfowl 19:5-24.
Salomonsen, F. 1970. Birds useful to man in Greenland. Pages 169-175 _in_ Productivity and conservation in northern circumpolar lands. International Union for Conservation of Nature and Natural Resources, Morges, Switzerland.
Salomonsen, F. 1974. Forslag til vedtægt om jagt på fuglene i Grønland. Diskussionsoplæg til kommunalbestyrelserne udarbejdet på opfordring af Det grønlandske Landsråd. Tidsskr. Grønland 1974(5):155-172.
Somer, E., and H. Appelquist. 1974. Changes and differences in mercury level in the Baltic and Kattegat compared to the North Atlantic using _Uria_ sp. (guillemot sp.) and _Cepphus grylle_ (black guillemot) as indicators. 9th Conf. of the Baltic Oceanographers, Kiel. 12 pp. Danish Isotope Centre, Copenhagen.
Sowl, L. W., and J. C. Bartonek. 1974. Seabirds--Alaska's most neglected resource. Trans. N. Am. Wildl. Nat. Resour. Conf. 39:117-126.
Strandgaard, H. 1964. The Danish bag record. I. Studies in game geography based on the Danish bag record for the years 1956-57 and 1957-58. Dan. Rev. Game Biol. 4(2):1-116.
Tull, C. E., P. Germain, and A. W. May. 1972. Mortality of thick-billed murres in the West Greenland salmon fishery. Nature (Lond.) 237(5349):42-44.
FOOTNOTES:
[67] Not counted.
[68] No estimate, but number insignificant.
[69] Species totally protected.
[70] _Branta bernicla_ is fully protected since 1972.
[71] _Somateria mollissima_, _Melanitta nigra_, and _M. fusca_.
[72] The "number of pairs" is calculated by multiplying the number of birds observed by 0.67 (Dyck and Meltofte 1975).
[73] A few species breed near freshwater lakes, but are marine during the nonbreeding season.
Present Status and Trends in Population of Seabirds in Norway
by
Einar Brun[74]
University of Tromsø Tromsø, Norway
Abstract
The most numerous seabird in Norway is the puffin _(Fratercula arctica)_, but its current breeding population of 1.25 million pairs is slowly declining. The kittiwake _(Rissa tridactyla)_, however, is increasing and establishing new colonies; its population now stands at 510,000 pairs. The population of the common murre _(Uria aalge)_, the seabird species most vulnerable to human activity, was about 160,000 breeding pairs in 1964 but is now decreasing at a rate of nearly 5% per year. Of the other alcids, the razorbill _(Alca torda)_ and thick-billed murre _(Uria lomvia)_ show similar declines, and the black guillemot _(Cepphus grylle)_ is maintaining a stable population. The fulmar _(Fulmarus glacialis)_ and the gannet _(Sula bassana)_ have both spread from the British Isles and have established a number of breeding colonies in Norway during this century. Evidently immigration of gannets is still occurring, since the observed rate of increase far exceeds the population's intrinsic rate of increase. The impact of human activity on bird mortality varies from species to species. The two most serious factors are coastal oil pollution and the use of fishing gear; direct hunting pressure accelerates the decline of murres and razorbills. Persistent toxic chemicals are not yet a serious problem in Norway.
Norway, with a coastline of more than 20,000 km, an abundance of islands, and areas of offshore upwelling, provides good conditions for a rich seabird fauna. A regional study of this seabird fauna has been undertaken as a sideline of basic marine research. Although the ultimate aim has been to evaluate the importance of seabirds in the energy flow of a marine ecosystem, a more realistic problem (given priority so far) has been to study yearly production and the dynamics behind changes in the breeding populations.
Good population estimates are of fundamental importance to studies of population dynamics. Because the available censuses of seabirds in Norway were few and largely inadequate, a long-term program was started in 1961. In the beginning, resources and assistance were very limited, and the work was concentrated on cliff-breeding seabirds, particularly the gannet _(Sula bassana)_, fulmar _(Fulmarus glacialis)_, kittiwake _(Rissa tridactyla)_, razorbill _(Alca torda)_, common murre _(Uria aalge)_, thick-billed murre _(U. lomvia)_, and puffin _(Fratercula arctica)_. Until 1970, the study involved making annual censuses in the approximately 20 major colonies of cliff-breeding seabirds and mapping the distribution of the quantitatively less important colonies.
Since 1970, the Norwegian seabird program has also involved more detailed studies in some selected colonies. In these colonies, emphasis has been on investigation of yearly production and of the factors limiting this production, and evaluation of the effects of human
## activity on the population growth.
Material and Methods
The logistics of census operations have gradually improved from the use of slow, local transportation to the use of fast pneumatic boats and, in more recent years, seaplanes. Various census methods have been used, depending on species and circumstances.
For puffins, a method based on measurement of feeding frequency and on the number of puffins per time unit that pass a particular observation post when they return from the feeding ground was used (Brun 1971_a_). Kittiwakes and gannets were readily censused by a combination of photographic methods and detailed counts in sample areas (Brun 1971_b_). Direct counting is by far the most accurate method for razorbills, murres, and fulmars; but in the larger colonies of common murre, lack of time permitted accurate counts for only a limited proportion of the cliff. Direct counts of individuals, the egg/chick ratio, and estimates of the relative size of the censused population were used to estimate the total population of the colony.
In a colony of kittiwakes near Tromsø, environmental factors that limit breeding success, such as temperature and wind exposure, were monitored throughout the breeding season on a data recorder, and detailed measurements of temperatures on and inside the eggs have been recorded. For further information about the influence of environmental parameters on incubation rhythm and nest attendance, the presence of the male and female at a particular nest was recorded by using radioactive bands and a Geiger-Muller tube connected to a pen recorder.
In a study of the effects of human activity, egg samples of selected species were analyzed for mercury, PCB, and DDT derivates. An effort was also made to obtain figures for the mortality caused by oil pollution and fishing gear as well as by direct hunting pressure.
Results
_Status and Trends of Cliff-breeding Species_
Puffin _(Fratercula arctica)_
By far the most numerous seabird in Norway is the puffin (Fig. 1), which is the only species with a breeding population of more than 1 million breeding pairs (Tables 1, 2). In a 1964 census (Brun 1966) the total breeding population was put at 1.5 million pairs. The current figure of 1.25 million pairs includes several newly discovered colonies and some not censused in 1964; it is more accurate than the previous census for most of the 15 largest colonies which make up 99.9% of the total population. The puffin population is concentrated in Troms and Nordland (94%), with only about 3% in Finnmark.
[Illustration: Fig. 1. Distribution of the puffin _(Fratercula arctica)_ in Norway. Numbers refer to localities listed in Table 2.]
Kittiwake _(Rissa tridactyla)_
The second most numerous seabird species in Norway is the kittiwake, which dominates in a number of the larger cliff colonies. Its distribution pattern differs from that of the puffin--the main occurrence of the kittiwake population (about 63%) is in Finnmark (Table 3).
Table 1. _Estimate of the numbers of seabirds breeding on the coast of Norway 1970-1974. Species are listed in descending order of breeding population size._
Thousands of Increase (+) or Species pairs[75] decline (-)
_Fratercula arctica_ 1250 - _Rissa tridactyla_ 510 + _Larus argentatus_ (260)[76] + _L. canus_ (150)[76] + _Uria aalge_ 100 - _L. marinus_ (40)[76] + _Phalacrocorax aristotelis_ 33 + _Alca torda_ 30 - _Cepphus grylle_ 22 0 _Sterna paradisaea_ (21)[76] - _S. hirundo_ (13)[76] - _Phalacrocorax carbo_ 12 + _L. fuscus_ 9[76] + _Stercorarius parasiticus_ (8) 0 _L. ridibundus_ 4[76] + _Fulmarus glacialis_ 1.1 + _U. lomvia_ 1.0 - _Hydrobates pelagicus_ ? ? _Sula bassana_ 0.76 + _Oceanodroma leucorrhoa_ ? ?
The annual production of kittiwakes shows enormous variation, both throughout the coastline and in different years; however, at our sample stations in north Norway, the mean production in 1974 (Table 4) was more stable and was near the minimum value necessary to maintain zero population growth.
This minimum production, mₓ (number of females produced per breeding female), can be computed from survival rates
mₓ = (1-P)/1ₓ = 0.13/0.57 = 0.23
where P is annual adult survival and 1ₓ is survival of fledged chicks up to first breeding. Data on survival are taken from Coulson and White (1959) and from Norwegian banding recoveries.
The kittiwake has, however, established a number of new colonies, and although the local increase in some of these is spectacular, the long-term change during the last 15 years is only about 1% increase per year in northern Norwegian colonies (E. Brun, unpublished data). In southern Norway, the population has increased much more rapidly (Brun 1971_c_).
Common murre _(Uria aalge)_
The common murre (Fig. 2) has shown a considerable decrease. The most spectacular decrease is at Sør-Fugløy, where a colony of 10,000 pairs in 1940 was reduced to 4,000 pairs in 1961, to 1,100 pairs in 1966, and to only about 10 breeding pairs in 1974 (Table 5). Most of the census work was done in 1964 and 1974. The general trend in population change, as expressed by the yearly decrease or increase, has been extrapolated forward to 1974 or back to 1964 for those colonies where censuses were missing for either of these years, to enable a better comparison (Table 6). The overall decrease in Norwegian colonies of the common murre is, thus, near 5% per year; the few cases with a positive trend are based either on very small figures or on extrapolation from old, inadequate censuses.
Thick-billed Murre _(Uria lomvia)_
The thick-billed murre (Fig. 3) was first proved to breed in Norwegian colonies in 1964; it was then found at three localities and has since been found breeding at eight localities (Table 7). It is now fairly certain that the thick-billed murre is not a newcomer but has remained unnoticed among the common murre for generations, possibly since the original immigration of the _Uria_ species after the last glacial period. Data are not sufficient to show whether this small population of thick-billed murres is decreasing at the same rate as the common murre.
Table 2. _Status of the puffin_ (Fratercula arctica) _in Norway (cf. Fig. 1)_.
Year of Number of Percent of Locality census pairs population
1. Kjør 1975 80 <0.1 2. Heglane 1970 4 <0.1 3. Ferkingstadøyene 1970 5 <0.1 4. Utsira 1970 2 <0.1 5. Utvær 1970 200 <0.1 6. Ryggsteinen 1970 2 <0.1 7. Veststeinen 1970 1,500 0.1 8. Einevarden 1970 1,500 0.1 9. Svinøy 1970 100 <0.1 10. Runde 1974 30,000 2.4 11. Saløy 1970 2 0.1 12. Sklinna 1974 2,000 0.2 13. Lovunden 1968 60,000 4.8 14. Fugløy i Gildeskål 1968 800 0.1 15. Røst 1964 700,000 55.7 16. Værøy 1974 70,000 5.6 17. Nykvåg 1967 40,000 3.2 18. Frugga 1975 5,000 0.4 19. Anda 1970 10,000 0.8 20. Bleik 1968 40,000 3.2 21. Sør-Fugløy 1968 40,000 3.2 22. Nord-Fugløy 1967 218,000 17.3 23. Loppa 1968 180 <0.1 24. Hjelmsøy 1964 20,000 1.6 25. Gjesværstappen 1973 18,000 1.4 26. Kongsøy 1966 30 <0.1 27. Syltefjord 1966 100 <0.1 28. Hornøy 1967 160 <0.1 29. Reinøy 1967 40 <0.1 Total 1,257,705 100.0
Razorbill _(Alca torda)_
Another colonial cliff-breeding alcid, the razorbill (Fig. 4), has a distribution pattern very similar to that of the common murre, but the individual colonies (Table 8) are, with one exception, smaller. The total breeding population was estimated at 36,000 pairs in 1966-69 (Brun 1969_b_); some more recent censuses show a definite decline, but data are not sufficient to estimate the overall decline in the Norwegian population. At most, the current breeding population is 30,000 pairs.
Fulmar _(Fulmarus glacialis)_
The fulmar is one of two species of seabirds that have spread from colonies in the British Isles and established themselves as breeding birds in Norway during this century (the other is the gannet).
[Illustration: =Fig. 2.= Distribution of the common murre _(Uria aalge)_ in Norway. Numbers refer to localities listed in Tables 5 and 6.]
[Illustration: =Fig. 3.= Distribution of the thick-billed murre _(Uria lomvia)_ in Norway. Numbers refer to localities listed in Table 7.]
Table 3. _Status of the kittiwake_ (Rissa tridactyla) _in Norway, and a comparison of distribution with that of the puffin_ (Fratercula arctica).
------------------------------------------------------------- Breeding pairs ------------------------------------------- _Rissa_ _Fratercula_ -------------------- -------------------- Number Number County (thousands) Percent (thousands) Percent ------------------------------------------------------------- Finnmark 321 62.9 38 3.0 Troms 9 1.8 258 20.5 Nordland 72 14.1 928 73.7 Trøndelag (S, N) 1 0.2 2 0.2 Møre and Romsdal 105 20.6 30 2.4 Sogn and Fjordane 1.9 0.4 3 0.2 Rogaland 0.1 -- <0.1 -- Total 510 100.0 1,259 100.0 -------------------------------------------------------------
The fulmar began nesting in the early 1920's on Runde, the only sizeable seabird colony in south Norway, off Alesund. Further immigration of birds from the British Isles probably occurred in the first 25 years, when the population increased about 10% annually to about 350 pairs in 1947 (Valeur 1947). Since then the population increase has slowed down to about 3% annually, and the population on Runde in 1971 was about 700 pairs (Table 9). From Runde, fulmars have spread not only to a number of islands in the same region, but also much farther afield--south to Utsira (59°18'N, 4°55'E) and north to Bleik (69°3'N, 15°42'E). The total Norwegian population of fulmars in 1971 was estimated at 1,100 pairs.
[Illustration: =Fig. 4.= Distribution of the razorbill _(Alta torda)_ in Norway. Numbers refer to localities listed in Table 8.]
[Illustration: =Fig. 5.= Distribution of the gannet _(Sula bassana)_ in Norway. Numbers refer to localities listed in Table 10.]
Table 4. _Annual production, mₓ, of the kittiwake_ (Rissa tridactyla) _at some North Norwegian coastal localities (mₓ = number of females produced per female)_.
------------------------------------------- Sample size Locality Year (number) mₓ ------------------------------------------- Vedøy, Røst 1972 852 0.21 Hekkingen, Troms 1974 264 0.46 Hjelmsøy 1974 357 0.18 Jarfjord 1974 146 0.31 Total 1,619 0.25 -----------------------------------------
Gannet _(Sula bassana)_
The gannet (Fig. 5), the most recently established and least numerous of the cliff-breeding seabirds, has the best-known population change. Like the fulmar, it was established in 1946 on Runde, and the first individuals were undoubtedly of British origin. During its entire breeding history on Runde, and also in two of the three new colonies in northern Norway established in the 1960's, the yearly increase has far exceeded the intrinsic rate of increase (Table 10); for gannets with a 50% breeding success, adult mortality of 6%, and 35% survival up to first breeding, the intrinsic rate of increase is about 2% per year. The Runde and Syltefjord colonies are naturally protected by their inaccessibility, but the colonies at Mosken and Nordmjele, which are on small islets, are both easily accessible. The Nordmjele colony, however, has been effectively protected from its start, whereas the Mosken colony has been open to visitors; this difference is probably reflected in their different breeding success and annual growth rate (Table 11). The breeding success necessary to maintain a stable population with the mortality figures given above is 34%:
mₓ = (1-P)/1ₓ = 0.66/0.35 = 0.17
For equal sex ratio, breeding success is 2 times mₓ = 0.34.
A British ringed gannet from Ailsa Craig (55°12'N, 5°07'W) was found nesting when 4 years old in the Nordmjele colony in 1970 (Brun 1972), giving direct evidence that immigration from colonies in Great Britain (Scotland) still takes place.
Table 5. _Status of the common murre_ (Uria aalge) _in Norway (cf. Fig. 2)_.
Last census Previous census No. of No. of breeding breeding Locality Year pairs Year pairs Reference
1. Utsira 1970 1 1950 10 Holgersen 1951 2. Utvær 1970 17 1948 55 Willgohs 1952 3. Veststeinen 1970 29 1950 40 Willgohs 1952 4. Klovningen 1970 35 1950 20 Willgohs 1952 5. Einevarden 1970 30 1952 25 Willgohs 1955 6. Runde 1974 6,000 1963 7,600 Brun 1969_a_ 7. Storholmen 1970 8 -- -- 8. Røst 1974 6,800 1964 9,700 Brun 1969_a_ 9. Værøy 1974 1,750 1964 2,400 Brun 1969_a_ 10. Nykvåg 1974 350 1966 430 Brun 1969_a_ 11. Bleik 1974 60 1952 90 Regnell 1957 1964 75 Brun 1969_a_ 12. Sør-Fugløy 1974 10 1940 10,000 Soot-Ryen 1941 1961 4,000 Brun 1963 1966 1,100 Brun 1969_a_ 13. Nord-Fugløy 1967 9,000 1963 15,000 Lütken 1965 14. Loppa 1974 500 1966 800 Brun 1969_a_ 15. Hjelmsøy 1974 70,000 1964 110,000 Brun 1965 1967 95,000 Brun 1969_a_ 16. Gjesværstappene 1973 580 1967 750 Brun 1969_a_ 17. Sværholtklubben 1973 20 1966 25 Brun 1969_a_ 18. Omgangsstauran 1973 70 1967 85 Brun 1969_a_ 19. Syltefjorden 1974 9,000 1966 12,300 Brun 1969_a_ 20. Hornøy 1974 500 1964 730 Brun 1969_a_ 21. Reinøy 1974 110 1964 160 Brun 1969_a_ 22. Kjøfjord 1970 21 -- -- 23. Skogerøy 1970 8 1967 6 Brun 1969_a_ 24. Sagfjord 1970 9 1967 12 Brun 1969_a_ 25. Kobbholmfjorden 1970 2 1967 1 Brun 1969_a_
_Estimates of Total Seabird Population in Norway_
In addition to the more detailed censuses of the cliff-breeding species dealt with so far, notes have been made on all seabirds observed during numerous flights along the Norwegian coast. Although a first attempt at putting a figure to all seabird species in Norway may be somewhat premature, it is believed that even an extrapolation combined with an educated guess is of some value until more accurate censuses covering the whole coast can be made. Although the data (Table 1) are arranged in the same way as the results from "Operation Seafarer" in the British Isles (Cramp et al. 1974), it must be stressed that the accuracy of the Norwegian figures, at least for the non-cliff-breeding birds, is far inferior to the very fine British data. The table includes data for two petrels (_Hydrobates pelagicus_, _Oceanodroma leucorrhoa_), which in Norway breed on Røst (well north of the Arctic Circle), where they have adapted to a delayed breeding season with egg laying in August because of the conflict of their nocturnal habits with the continuous daylight due to the midnight sun. Of the present population trends that are given for each species in Table 1, all auks except the black guillemot _(Cepphus grylle)_ are decreasing, whereas the gulls, the gannets, and the fulmars are increasing.
Table 6. _Population trends in colonies of the common murre_ (Uria aalge) _in Norway. Numbers for 1964 and 1974 are, when not censused those years, extrapolated from present trends, using estimated yearly decrease or increase from all available census figures._
Number of Percentage yearly breeding pairs[77] decrease (-) or Locality 1964 1974 increase (+)
1. Utsira 2 1 -12.2 2. Utvær 23 14 -5.5 3. Veststeinen 32 27 -1.6 4. Klovningen 30 39 +2.8 5. Einevarden 28 31 +1.0 6. Runde 7,438 _6,000_ -2.2 7. Storholmen 9 7 (-2.2)[b],[c] 8. Røst _9,700_ _6,800_ -3.6 9. Værøy _2,400_ _1,750_ -3.2 10. Nykvåg 453 _350_ -2.6 11. Bleik _75_ _60_ -2.3 12. Sør-Fugløy 1,844 _10_ -68.5 13. Nord-Fugløy 13,201 3,681 -13.6 14. Loppa 900 _500_ -6.1 15. Hjelmsøy _110,000_ _70,000_ -4.6 16. Gjesværstappen 853 556 -4.4 17. Sværholtklubben 27 19 -3.2 18. Omgangsstauran 94 68 -3.3 19. Syltefjorden 13,299 _9,000_ -4.0 20. Hornøy _730_ _500_ -3.9 21. Reinøy _160_ _110_ -3.8 22. Kjøfjord 21 20 (-0.4)[78],[79] 23. Skogerøy 5 12 +10.1 24. Sagfjord 16 6 -10.1 25. Kobbholmfjord 1 5 +26.0 Total 161,341 99,566 -4.9
Table 7. _Status of the thick-billed murre_ (Uria lomvia) _in Norway (cf. Fig. 3)_.
No. of Percentage of breeding total _Uria_ Locality Year pairs population
1. Vedøy, Røst 1974 15 0.3 2. Værøy 1966 20 0.9 3. Hjelmsøy 1974 850 1.2 4. Gjesværstappene 1973 25 4.3 5. Syltefjord 1970 90 0.9 6. Hornøy 1966 55 8.1 7. Reinøy 1964 1 0.6 8. Kjøfjord 1970 1 4.8 Estimated number, Norway, 1974 >1,000 ca. 1.0
Table 8. _Status of the razorbill_ (Alca torda) _in Norway (cf. Fig. 4)_.
-------------------------------------------------- No. of Locality Year breeding pairs Percent -------------------------------------------------- 1. Kjør 1970 1 <0.1 2. Utsira 1970 25 0.1 3. Utvær 1970 16 0.1 4. Veststeinen 1970 22 0.1 5. Klovningen 1970 12 <0.1 6. Einevarden 1970 45 0.2 7. Runde 1974 2,800 9.5 8. Sklinna 1974 15 0.1 9. Lovunden 1968 8 <0.1 10. Røst 1974 3,900 13.2 11. Værøy 1974 800 2.7 12. Nykvåg 1966 250 0.8 13. Bleik 1968 28 0.1 14. Sør-Fugløy 1974 15 0.1 15. Nord-Fugløy 1967 10,000 33.8 16. Loppa 1969 750 2.5 17. Hjelmsøy 1974 7,000 23.7 18. Gjesvær 1973 2,500 8.5 19. Sværholtklubben 1973 18 0.1 20. Omgangsstauran 1973 6 <0.1 21. Kongsøy 1966 8 <0.1 22. Syltefjorden 1966 1,200 4.1 23. Hornøy 1967 65 0.2 24. Reinøy 1967 55 0.2 25. Kjøfjord 1970 9 <0.1 26. Skogerøy 1970 4 <0.1 27. Jarfjordnes 1970 3 <0.1 Total ca. 30,000 --------------------------------------------------
Since the coastline of Norway is about the same length as the coastline of Great Britain and Ireland, it is interesting to compare the population figures (Table 12), although the accuracy is very different. Populations of auks and gulls are similar in both areas, but the species composition is different. There are more terns in the British Isles, but skuas _(Catharacta skua)_, shags _(Phalacrocorax aristotelis)_, and great cormorants _(P. carbo)_ are present in similar numbers. The most striking difference is the very small number of procelli-forms and gannets in Norway compared to Britain and Ireland, where they are almost as numerous as the gulls and the auks.
Table 9. _Status of the fulmar_ (Fulmarus glacialis) _in Norway_.
--------------------------------------- Number of Number of breeding County localities pairs --------------------------------------- Nordland 6 140 Møre and Romsdal 7 945 Sogn and Fjordane 2 11 Rogaland 2 2 Total 17 1,098 ---------------------------------------
Table 10. _Population increase of the gannet_ (Sula bassana) _in Norway (cf. Fig. 5)_.
---------------------------------------------------------------------------- Mean yearly No. of breeding pairs Year growth rate ---------------------------------- Colony established 1969-1974 (%) 1969 1970 1971 1972 1973 1974 ---------------------------------------------------------------------------- 1. Runde 1946 8.4 330 331 383 422 450 494 2. Mosken ca. 1960 5.4 50 83 77 60 62 65 3. Nordmjele 1967 83.3 7 36 65 103 127 145 4. Syltefjord 1961 14.5 28 29 44 48 51 55 Total 12.8 415 479 569 633 690 759 Yearly growth rate (%) 15.4 18.8 11.2 9.0 10.0 ----------------------------------------------------------------------------
Discussion
_Impact of Human Activity_
Direct Exploitation
According to Norwegian laws, all seabirds, with the exception (for some odd reason) of the gannet and fulmar, can be hunted from 21 August to 1 March. However, only the two species of murre and the razorbill are still regularly hunted and, although no statistics support it, an estimate based on interviews with some of the hunters reveals that murres and razorbills are shot in the ratio of about 50:1. One man can shoot as many as 380 murres and razorbills during a winter season as a sideline to fishing. Although not many hunt on this scale, an absolute minimum of 5,000 murres and razorbills are killed this way each season.
A new law based on modern principles of conservation has been under consideration for several years, and this will mean an improvement. However, the speed of the decline of the auks, particularly the murres, makes it imperative to stop this hunting immediately, and it is of very little economic importance to the few who take part. Some illegal "fishing" for auks still takes place at Røst and Vaerøy, where fishnets are anchored over wooden frames outside the auk colonies at the beginning of the nesting season. At Vedøy on Røst in 1972, up to 80 murres were taken daily. Thus an estimated total of 500-700 murres were taken that year--about 5% of the breeding population on this island.
Egg collecting was important during World War II, but in these more affluent times and because of the relative inaccessibility of the auks' nests, egg collecting is now both less attractive and less important. Human disturbance of the breeding colonies, however, is gradually becoming a more serious factor.
Table 11. _Comparison of annual growth rate and breeding success in two colonies of gannets_ (Sula bassana).
---------------------------------------------- Mosken Nordmjele ---------------- ---------------- Annual Breeding Annual Breeding growth success growth success rate (%) rate (%) ---------------------------------------------- 1969 62 -- 1.66 5.14 1970 51 61 0.93 1.81 1971 36 46 0.78 1.58 1972 33 62 1.03 1.23 1973 50 35 1.05 1.14 1974 12 39
1969-1974 1.05 40 1.83 46 ----------------------------------------------
Fishing Gear
Although on a scale different from that in western Greenland, drift-net and longline fishing for Atlantic salmon _(Salmo salar)_ outside the 19-km (12-mile) limit off the northern Norwegian coast present a serious mortality hazard to some seabirds. Reliable data exist only for the longline fisheries. In the 1969 season (with 75 effective days from mid-March to mid-June), one boat using 1,040 hooks per day caught 294 birds: 52 fulmars, 3 gannets, 43 kittiwakes, 107 murres, and 89 puffins. No razorbills were identified, but they may have been included in the murre figure. If this sample is representative, the 100 or so Norwegian boats using longlines plus about 20 Danish boats (which used 4,000-6,000 hooks per day and consequently caught more birds) would have caught roughly 10,000 fulmars, 600 gannets, 9,000 kittiwakes, 21,000 murres, and 18,000 puffins in the 1969 season. The drift-nets in Norwegian waters are reported to be less damaging to seabirds than are the longlines, but even without adding the figures from the drift-nets, the numbers are substantial in view of the size of the Norwegian breeding populations.
Table 12. _Comparison of the number of seabirds breeding on the coasts of Great Britain and Ireland (Cramp et al. 1974) and on the coast of Norway._
Number of breeding pairs[80]
Species Great Britain and Ireland Norway
_Fulmarus glacialis_ 306,000 1,100 _Puffinus puffinus_ > 175,000 -- _Hydrobates pelagicus_ 10⁵ or 10⁶ 10³ or 10⁴ _Oceanodroma leucorrhoa_ 10⁴ 10² _Sula bassana_ 138,000 760 _Phalacrocorax carbo_ 8,100 12,000 _P. aristotelis_ 31,000 33,000 _Stercorarius skua_ 3,100 1[81] _S. parasiticus_ 1,100 8,000 _Larus ridibundus_ 74,000 4,000[82] _L. canus_ 12,000 (150,000)[82] _L. fuscus_ 47,000 9,000[82] _L. argentatus_ 333,000 (260,000)[82] _L. marinus_ 22,000 (40,000)[82] _Rissa tridactyla_ 470,000 510,000 _Sterna sandvicensis_ 12,000 -- _S. dougalli_ 2,300 -- _S. hirundo_ 14,000 (13,000)[82] _S. paradisaea_ (31,000) (21,000)[82] _S. albifrons_ 1,800 -- _Alca torda_ (144,000) 30,000 _Uria aalge_ (577,000) 100,000 _U. lomvia_ -- 1,000 _Cepphus grylle_ 8,300 22,000 _Fratercula arctica_ (490,000) 1,250,000 Total ca. 3,000,000 ca. 2,500,000
Use of fishing gear close inshore, especially pound nets set near colonies of diving seabirds, can take a heavy toll under special weather conditions. In 1969 at Runde, 85 birds, mainly auks, shags, and some diving ducks, were caught in one net in 24 hours; this is an exceptionally high figure. The total loss of diving seabirds in pound nets per year in Norway (about 6,000 nets fishing for 40 days) was estimated to be at least 40,000 birds in 1969. The data are too unreliable to give species composition, however, since fishermen rarely make note of this.
Amounts of fish offal from offshore trawlers, drift-netters, and longline fishing boats have increased in recent years, and some seabirds, particularly kittiwakes, fulmars, and gannets make use of this new and readily available food source. Thus, although the use of fishing gear is a serious threat to seabird survival, fish waste from the same boats provides an abundant food supply for the more pelagic species.
Pollution
No quantitative investigation similar to those made in Great Britain, Netherlands, and Belgium (Tanis and Bruyns 1968) has been carried out on the impact of oil pollution on seabirds in Norway. The northern Norwegian population of the most threatened species, murres and razorbills, winter in North Sea coastal areas where oil pollution and oiled birds have most frequently been found. It is possible that whole populations winter every year in the same area, and if they happen to be in a heavily polluted area, a particular population may be seriously affected. Such an occurrence is believed to have caused the dramatic decline in the Sør Fugløy population (cf. Table 5).
Although not yet serious, pollution by persistent toxic chemicals such as organochlorines and mercury is a problem even in northern Norway, because the northbound coastal current brings water masses, plankton, and nekton from areas with industrial wastes. Analysis of the eggs of herring gull _(Larus argentatus)_, murre, razorbill, and kittiwake in 1972 showed relatively low levels of mercury; the only species with a relatively high level of mercury (mean 0.58 ppm) was the gannet (Fimreite et al. 1974). This elevated toxic burden may have caused a reduced breeding success for the gannet. Analysis of concentrations of PCB's and DDT/DDE showed that the levels of these organochlorines were generally also lower in Norwegian seabirds than in those of Britain (Fimreite et al. 1977).
Protection and Necessary Conservation Measures
Total protection of some of the important seabird colonies (including the surrounding nearshore waters) has proven very effective, especially when the protection is so strict that landing is prohibited for a specified period during incubation and fledging. However, to reduce the rapid decrease of some species, a total hunting prohibition of those species must be instigated, oil pollution must be reduced, and the fisheries must be regulated to reduce the mortality caused by fishing gear.
_Natural Factors Influencing Breeding Success_
The factors discussed so far are all results of human activities which directly or indirectly influence seabird mortality. Yearly production or breeding success is, however, also influenced by a number of natural factors such as food supply, availability of suitable nest sites, predation, climate (weather), and population-dependent factors (age, breeding experience, population density). For the gannet, whose breeding success has been studied in some detail (Brun 1974), it was concluded that the differences in exposure (to severe weather) and in breeding experience were the most important factors responsible for annual fluctuation in breeding success. For such species as murres, razorbills, and puffins, food supply is an important limiting factor. If the spawning of the fish species that constitute their main food items fails 1 year for some reason, it may be very difficult for the seabirds to find an adequate alternative food supply and most of the chicks starve to death. To a lesser degree, food supply is limiting for the kittiwake, which seems to be more influenced by bad weather (Norderhaug et al. 1977).
Conclusion
Two opposite population trends have been observed--the decline of the coastal-bound murres and razorbills and the increase and spread of the more pelagic gannets, fulmars, and kittiwakes. These changes are attributed to a number of factors, which include the following:
• The diving murres and razorbills spend a major part of their time swimming on the surface and are thus more susceptible to surface oil pollution than are the pelagic species.
• The coastal-bound murres and razorbills are quite heavily hunted, whereas there is no regular hunting of the pelagic species.
• The pelagic species are mainly surface feeders and do not swim under water, and are thus less affected by the drift-nets than are diving birds.
• The pelagic species are the principal beneficiaries of recently increased supply of fish offal from trawlers.
Acknowledgments
The program was originally sponsored by Tromsø Museum, later University of Tromsø, and has been financially supported by the Norwegian Research Council for Science and Humanities and the Norwegian Game Fund. The research grants are gratefully acknowledged. I also thank my field assistants and the many local people at the breeding sites who have been most helpful.
References
Brun, E. 1963. Ornithological features of Nord-Fugløy and Sør-Fugløy. Astarte 1(22):1-13.
Brun, E. 1965. Brunnich's Guillemot, _Uria lomvia_ (L.), as a breeding bird in Norway. (In Norwegian, English summary.) Sterna 6:229-250.
Brun, E. 1966. The breeding population of puffins _(Fratercula arctica)_ in Norway. (In Norwegian, English summary.) Sterna 7:1-17.
Brun, E. 1969_a_. The breeding distribution and population of guillemots _(Uria aalge)_ in Norway. (In Norwegian, English summary.) Sterna 8:209-224.
Brun, E. 1969_b_. The breeding distribution and population of razorbills _(Alca torda)_ in Norway. (In Norwegian, English summary.) Sterna 8:345-359.
Brun, E. 1971_a_. Census of Puffins _(Fratercula arctica)_ on Nord-Fugløy, Troms. Astarte 4:41-45.
Brun, E. 1971_b_. Breeding distribution and population of cliff-breeding seabirds in Sør-Varanger, north Norway. Astarte 4:53-60.
Brun, E. 1971_c_. Population changes of some seabirds in south Norway. (In Norwegian, English summary.) Sterna 10:35-56.
Brun, E. 1972. Establishment and population increase of the gannet _Sula bassana_ in Norway. Ornis Scand. 3:27-38.
Brun, E. 1974. Breeding success of gannets _Sula bassana_ at Nordmjele, Andøya, north Norway. Astarte 7:77-89.
Coulson, J. C., and E. White. 1959. The post-fledging mortality of the kittiwake. Bird Study 6:97-102.
Cramp, S., W. R. P. Bourne, and D. Saunders. 1974. The seabirds of Britain and Ireland. Collins, London. 287 pp.
Fimreite, N., J. E. Bjerk, N. Kveseth, and E. Brun. 1977. DDE and PCBs in eggs of Norwegian seabirds. Astarte 10:15-20.
Fimreite, N., E. Brun, A. Frøslie, P. Frederichsen, and N. Gundersen. 1974. Mercury in eggs of Norwegian seabirds. Astarte 7:71-75.
Holgersen, H. 1951. Investigations of seabirds in Rogaland 1949-1950. (In Norwegian, English summary.) Stavanger Mus. Arb. 1950:61-76.
Lütken, E. 1965. The breeding birds on Nord-Fugløy, north Norway, their distribution and numbers. (In Danish, English summary.) Dansk Orn. For. Tidsskr. 58:166-193.
Norderhaug, M., E. Brun, and G. U. Møllen. 1977. Barentshavets sjøfuglressurser. Forhold i tilknytning til status, miljøproblemer of forshningsoppgave. Medd. Norsk Polar Inst. 104:1-119.
Regnell, S. 1957. Fran det nordnorska fåggelberget Bleiksøya. Fauna Flora, Upps. 52:199-202.
Soot-Ryen, T. 1941. The seabird rookeries of Troms county. (In Norwegian, English summary.) Tromsø Mus. Aarsh. 62(1):1-112.
Tanis, J. J. C., and M. F. M. Bruyns. 1968. The impact of oil pollution on seabirds in Europe. Proc. Int. Conf. Oil Pollution of the Sea 1968:67-74.
Valeur, P. 1947. Havhesten og havsula på Rundøy. Naturen 70:370-379.
Willgohs, J. F. 1952. On the distribution of some seabirds in western Norway. Univ. Bergen Årb. 1951 Naturvit. Rekke (9):1-20.
Willgohs, J. F. 1955. Om forekomsten av endel kyst-og sjøfugl på Vestlandet. Fauna, Oslo 8:16-27.
FOOTNOTES:
[74] Deceased.
[75] Numbers in parentheses are not based on a complete census of the coast.
[76] In addition, an unknown number of pairs breeding inland.
[77] Numbers in italics were censused from 1964 and 1974.
[78] Estimated values from trends in neighboring colonies.
[79] Numbers in parentheses are not based on a complete census of the whole coast.
[80] Numbers in parentheses are not based on a complete census of the whole coast.
[81] New in 1975 (Wim Vader, personal communication).
[82] In addition, an unknown number of pairs breeding inland.
SYMPOSIUM SUMMARY
Conservation of Marine Birds of Northern North America--A Summary
by
Ian C. T. Nisbet
Massachusetts Audubon Society Lincoln, Massachusetts 01773
This is not going to be a straightforward summary of the conference because it is my view that a number of important topics have not been addressed. In particular, what was supposed to be the main theme of the conference--the need for _conservation_ of marine birds of northern North America--has been taken for granted by many speakers and has been treated by others in what may be a misleadingly brief way. So instead of simply summarizing the information that has been presented in the papers, I want to give my own views about how we should use this information to make a case for the conservation of marine birds. I feel strongly that we can make a good case for conserving them, and that we know enough to start doing so. The task of making a case for conservation and of proposing priorities for action has been left to me as the conference summarizer.
## Particularly in the first half of this conference, we heard a long
series of accounts of the birds of the area which stressed our ignorance--large amounts of information that was not known and large amounts of research that needed to be done. Now, I have an unexpected advantage over most of these speakers in that I have very little direct experience in the area. What I learned from their papers, not having any very clear picture of the islands, the birds, their habits, or the food that they eat, is that we already know quite a lot about the marine birds of northern North America. We certainly know enough to decide what we ought to do next and how to take the basic steps in conserving them.
After listening to the presentations, reading the abstracts, and studying the maps posted in the conference hall, I drew up a list of 10 points that I will first list and then elaborate on.
• We know that we are discussing a very important biological resource which has been neglected for a long time.
• We know roughly what this resource consists of and which aspects of it are biologically important.
• We know why this resource is in its present condition, and we know something about the ways in which it is related to other resources.
• We know a certain number of things that the birds do which make them vulnerable to changes in the environment.
• We know that the resource has already been disturbed in the past, both by human-induced and by natural changes, and we know that it has already been damaged.
• We can identify at least some of the major threats that the resource will face in the next few years.
• We know that the resource can be conserved, at least to a modest and
## partial extent.
• We have a fairly good idea of what we ought to do now to start conserving the resource.
• We have some ideas--so far rather rough and ill-formulated--about why we should conserve the resource.
• We know--or so I believe--that it is practicable and economically feasible to conserve the resource.
I am sure that there will be some disagreements with some of these assertions, especially with the last two, so I will give reasons why I believe that we should conserve these birds and that we can afford to do so.
Magnitude and Importance of the Resource
The papers in the first half of the conference which reviewed the abundance and distribution of the birds in the northern North Pacific Ocean, the Bering Sea, and adjacent seas suggested that we are dealing with numbers of birds of the order of 100 million. That is 100 million birds at sea plus some unknown number of millions of birds along the shore. We do not have to take these numbers literally--I am sure that the persons who produced them did not mean them to be taken literally--but certainly we are talking about something on the order of tens of millions and not much more than some hundreds of millions. At least, it is on the order of a hundred million rather than ten million or a billion. I do not think it an exaggeration to say that this is one of the great neglected biological resources of the world.
Characteristics of the Resource
Three important aspects of this resource have not been identified clearly in the papers delivered at the conference, in part because the papers summarizing the biological surveys did not include much of the detail that was available in the maps posted in the conference hall. [Maps in this volume do not show the detail of those posted.] These are the numerical abundance of the birds, their diversity, and their unique characteristics.
As to abundance, figures have been mentioned on the order of 50 million for shearwaters (_Puffinus_ spp.) and 25 million for murres (_Uria_ spp.). For other species the quoted numbers have been less specific, but I would estimate from what I have read and heard that the total population must run into millions for eiders (_Somateria_ spp.), kittiwakes _(Rissea brevirostris)_, and fulmars _(Fulmarus glacialis)_, and doubtless for other species. The numbers of the smaller alcids, in
## particular, must be very great.
As to diversity, there is an impressive number of species and a wide variety of habitats. We have been shown in the photographs some spectacular island colonies, particularly in the Bering Sea and the Aleutian Islands, some of which have a remarkable variety of species. Several different definitions of "seabird" have been used at this conference, but certainly there are dozens, and probably scores, of genuine marine species that either breed in the area or use it as a major nonbreeding area. The collection of birds in the area of the North Pacific and the Bering seas seems more impressive in terms of both abundance and diversity than anything in the north Atlantic Ocean, which has been so much more fully studied.
As to the uniqueness, there has been almost no mention of the endemic species at the conference. It is therefore important to emphasize in this summary that a significant group of marine or coastal birds is endemic to this area. These birds include the red-legged kittiwake (_Rissa_ spp.), the Aleutian tern _(Sterna aleutica)_, the spectacled eider _(Somateria fischeri)_, the emperor goose _(Philacte canagica)_, and the red-faced cormorant _(Phalacrocorax urile)_; a number of alcids, including the whiskered _(Aethia pygmaea)_, parakeet _(Cyclorrhynchus psittacula)_, crested _(A. cristatella)_, and least auklets _(A. pusilla)_; the horned puffin _(Fratercula corniculata)_; and Kittlitz's murrelet _(Brachyramphus brevirostris)_. In addition, we should not forget some migrants that make exclusive use of this area in their nonbreeding season. These include the short-tailed albatross _(Diomedea albatrus)_, the scaled petrel _(Pterodroma inexpectata)_, and I believe also Cook's petrel _(P. cookii)_, which has not previously been mentioned. From the little we know about its off-season distribution, the short-tailed albatross appears to use these waters exclusively; hence it has as much claim to be regarded as an endangered species of the United States as the whooping crane _(Grus americana)_.
Perusal of the lists of species presented at the conference brings out one important point. Although we are meeting in the United States and have been looking at the birds from a United States-Canadian viewpoint, this is truly an international resource in almost every respect that I have mentioned. The most abundant species, in terms of both numbers and biomass, is probably the short-tailed shearwater, a migrant from the southern hemisphere. The rarest species, and the most endangered, is the short-tailed albatross, which breeds only on one island in Japan. There are migrants in large numbers from Chile, Australia, New Zealand, and especially the Soviet Union. All of these use the area of ocean and shallow sea that we have been considering as a major area for a substantial part of their annual cycle.
What more do we need to know about the extent of this resource? In my opinion we should not place high priority on determining the exact numbers of the birds--whether there are 25 million or 26 million murres, for example. It would be difficult, if not impossible, to determine such numbers in the kind of geographical and climatic area we are considering. Moreover, even if we were to measure the populations with great accuracy and to determine in a few years that they had changed by 10%, we would not be able to draw any conclusions about the reasons for the change or what should be done about it.
To set priorities for further exploration, I think it is more important to survey in greater detail the general distribution of the breeding colonies. So far, we know the location of only the largest colonies; we know almost nothing about the colonies of a mere 10,000 pairs or less. So I think future surveys should concentrate on locating the medium-sized colonies and getting some impression of roughly how many smaller colonies there are. It is important to locate and be sure that we know of all the major colonies that have a considerable number of species; these large, diverse colonies should be given priority for conservation. Most important of all, we need to locate and survey the endemic species with some precision. This need is especially great for the species that we suspect are limited to small areas or that may otherwise be particularly vulnerable.
If we are to measure population changes over the next few decades, it is of course essential to have a good base-line survey. However, I do not think it is either practicable or desirable to try to inventory the entire population of breeding seabirds with great accuracy. A more realistic and worthwhile program would be to select some sample colonies and to catalogue these sample areas in some detail, preferably with a photographic record, so that they can be resurveyed in later years to determine whether substantial population changes have taken place. Criteria for selection of sample colonies for inclusion in this base-line survey should include not only numerical size and species diversity but also ease of access, ease of observation, and the practicability of obtaining good photographic records.
Ecology and Functioning of the Resource
In the opening session of this conference, several speakers reviewed our general knowledge of the ecology of seabirds; others summarized our specific knowledge of the birds of the North Pacific, Bering, and adjacent seas, and their relation to physical and biological factors in the environment. There is no need to summarize these reviews again here except to point out that information on the relation between the birds and the marine environment is being generated very rapidly. We are beginning to understand the factors that control the breeding distribution of the individual species, their foraging strategies, and their dispersion at sea, at least in summer. However, it is clear from what has been said at this conference that we know much less about their ecology and distribution in winter. This lack of information is important because conflicting opinions have been expressed as to whether factors operating in the winter range or at the breeding colonies are more critical in limiting population size.
It is evident from what was said in the opening session that the distribution of the birds is very closely related to the distribution of marine resources. It is clearly no accident that the distribution of large numbers of many species of birds coincides with that of the major fisheries. Similarly, it is no accident that there is a relation between the distribution of birds and the extent of the continental shelf. These coincidences, which reflect the fundamental dependence of both birds and fish upon marine productivity, set the stage for existing and further conflicts between conservation of the birds and human exploitation of other resources of the area.
Perhaps the most significant gap in our knowledge of North Pacific seabirds is in the area of productivity and demography. As far as I can judge, we know almost nothing about the breeding success of these birds, their post-fledging survival, their longevity, their age at first breeding, the age structure of their populations, the fluctuations in their breeding performance, or their survival from year to year. For most species, we lack even the most basic life history and life table information.
If we can argue by analogy from studies made in other parts of the world, including the North Atlantic, we can make some basic generalizations that we would expect to apply to the birds of our area. We know that as a class seabirds have some peculiar characteristics which make them difficult to manage and cause some of the problems we have in conserving them. In general, they are long-lived and breed slowly, most lay small clutches, and the historical experience is that they take a very long time to recover from depletion of population. Many have an irregular breeding performance; some have long series of bad years interspersed with occasional years of good breeding success. Many seabird populations have traditionally fluctuated, as exemplified by those of the North Atlantic, whose fluctuations were described by W. H. Drury and W. R. P. Bourne.
Some species of seabirds are conservative, staying in the same colonies for many years or generations. Others are volatile, dispersing freely from one site to another and forming new colonies in an unpredictable way. Seabirds exhibit a wide range of ecological adaptations; some are highly specialized, others are highly generalized and adaptable. These differences can be very important when their environment changes, as D. N. Nettleship's film "Puffins, predators, and pirates" graphically illustrated.
As M. T. Myres pointed out on the 1st day of the conference, seabird populations exhibit both short-and long-term fluctuations. Long-term fluctuations are those that take place over times comparable to the generation time of the species, which may be many years or even decades for some seabirds. By surveying populations and measuring changes in them, we usually obtain information only about long-term population trends, reflecting long-term changes in the environment. Short-term perturbations in the environment are usually not reflected quickly by changes in total population--certainly not by changes that we can measure with the accuracy of our present-day census techniques. Many of the man-made changes we are concerned about are short-term. To identify their effects we should look not for changes in total population but rather for changes in biological parameters, such as the first-year survival rate or the number of young raised. I therefore suggest that some of the most critical parameters to be measured are changes in age structure of populations. We should therefore select as biological monitors species that can readily be aged--for example, gulls, which have a sequence of distinguishable immature plumages.
In specifying gaps in our knowledge of the ecology of birds, we should set clear priorities rather than compile a long "shopping list" of research projects. On the basis of the foregoing survey, I would suggest the following as priority items for further study. First, we need to know a lot more about winter distribution, not only of the marine birds, but also of inshore and coastal species. Second, we need to study in greater detail the relation between the day-to-day distribution of birds and the local patchiness of the resources on which they depend. Evidence that seabirds are able to locate and use fluctuating and shifting food sources has been given by several speakers at the conference. We need to understand how birds locate these resources and what relation this has to their survival and vulnerability to human activities. There is a special need to study the ecology of endemic species because their conservation is of special importance. We need to learn more about the relation of the birds to the commercial fisheries, both to resolve existing or alleged conflicts and to avert future problems.
However, I believe that the highest research priority should be given to obtaining basic information on reproductive success and life table data for some representative species. Clearly, we cannot study many species in detail, but in selecting key species for such studies we should pick a variety of ecological types--for example, at least one generalist species and one specialist, one sedentary species and one migrant, one species at a high trophic level and one at a low trophic level.
For the purpose for which we convened this symposium--conservation--I do not think that we need detailed knowledge of the factors which regulate populations. Such knowledge is, of course, of immense biological interest and will ultimately be needed for effective long-term management. However, it does not have immediate or even medium-term relevance to the urgent problems of conservation that we now face. What we do need to do is to set up some long-term studies of a few carefully selected species--preferably long-lived species--so that we can trace the effect of environmental fluctuations on their performance for a long period.
Vulnerability of the Resource
We already understand a number of factors that make some of these bird populations particularly vulnerable to the kind of human activities which we can envisage in the next decade or two. Most of the breeding birds concentrate on islands where they are vulnerable to predators and to human disturbance. Many of them concentrate in flocks on human fishing grounds and over other areas of the continental shelf which are likely to be the focus of human activity in the near future. In particular, some of the birds are known to concentrate in the passes through the Aleutian Islands, where they will be particularly vulnerable to future oil spills. In all these ways the birds are concentrated in areas where they are likely to receive disproportionate impacts from human activity and exploitation.
One point that has been barely mentioned in this symposium is the effect of molting on the vulnerability of some of these populations. The eiders, for example, concentrate on molting grounds in the Arctic. The exact location of these molting grounds may not be fully known, but we certainly know that the birds molt somewhere in an area where they will be vulnerable to oil spills (and also to human hunting if the people who move to the Arctic choose to hunt them). Nor are eiders the only species that are flightless when they molt. Some alcids and loons are also flightless for short periods and, hence, particularly vulnerable to oil spills during molt.
Past Damage to the Resource
In the speech opening the symposium, Assistant Secretary Reed referred to this biological resource as still relatively unspoiled. While "relatively" may be an appropriate word, we do have spectacular evidence of changes and damage to these bird populations. The use of the Aleutian Islands for fox farming seems to me a quite horrifying situation. We know also that the early whalers and sealers exploited seabird populations. Although I know of little specific information about the effects of such exploitation on birds in the northern North Pacific, D. G. Ainley in his survey of historical records from the Farallon Islands has shown very clearly the massive effects of human exploitation of birds, starting early in the 19th century. In our area of discussion alone, one species (the spectacled cormorant) is extinct and another (the short-tailed albatross) became virtually extinct and is still very rare. I believe that one or two southern hemisphere species, which must have been substantial elements in the northern summer bird population, have also been seriously depleted as a result of human activity on their breeding grounds.
Several speakers emphasized the importance of long-term fluctuations in bird populations resulting from natural causes, including some examples from the North Pacific. Other types of human activity must also have had some indirect effects on the birds. For example, whaling and sealing in the 19th century must have provided large amounts of food for scavenging birds and eliminated important competitors for the larger fish-eating birds. A similar experiment is now in progress as the predatory fish are being overfished.
Major Threats to the Bird Populations
We now know enough about the distribution and ecology of the seabirds to identify the major threats to them that are likely to be posed by the projected increase in human activity in the coming decades. The relative importance of these threats clearly varies from species to species and from area to area. However, I think that few of us would disagree that the largest single threat in the area as a whole is posed by oil, not only by the prospect of large-scale drilling for oil on the Alaskan continental shelf but also by prospective spills during transportation and deliberate dumping from ships.
My guess is that the second most important threat to the seabirds of the northern North Pacific is the presence of introduced predators, especially foxes and rats, at the breeding colonies. Much of the damage inflicted by these predators may already have been done, but I think their continuing presence is likely to have as great a negative effect on the bird populations as anything else discussed at the conference.
The relative importance of the other identifiable threats to the birds is even more conjectural. Drowning of diving birds in fishnets is obviously of great potential impact, but its importance depends greatly on the rapidly changing practices of fishermen. This problem must be kept under close surveillance, and the establishment and enforcement of international agreements will be critical.
Mineral development has not been mentioned much. It is my understanding that there are prospects for substantial onshore, and perhaps offshore, developments of heavy metal minerals. These are likely to lead to local disturbance in the coastal zone, and the tailings in particular may well pose a threat to coastal and inshore birds.
Ocean dumping has not been mentioned. I do not expect that there will be much dumping of toxic chemicals from Alaskan industries, but we must remember that this area is downstream from Japan and the Soviet Union. I do not know the current practices of these countries, but the unregulated dumping of toxic substances from some European countries apparently has led to large-scale pollution problems in the North Atlantic.
On present evidence, persistent pesticides and polychlorinated biphenyls (PCB's) do not seem to pose a significant threat to north Pacific seabirds, although high levels of PCB's have been reported in shearwaters off the California coast. In my judgment, we have probably turned the corner in regulating these chemicals, at least in the northern hemisphere, and their impact will probably not be allowed to get worse.
Human disturbance is obviously going to get very much worse, both from the influx of new human populations who will be involved in more industrialized activities in Alaska and from the likely increase in tourism. A matter of particular concern is the prospective influx of natural history tours, which can have major adverse effects if not carefully regulated.
Finally, we should not forget the impact of natural phenomena, including climatic changes and vulcanism. Bearing in mind the experience of Katmai, we might expect a natural disaster to strike a major bird colony at any moment.
Practicability of Conservation
Experience from other countries, as related in various papers at this conference, has shown that conservation of seabirds is possible and practicable, even in remote and inaccessible areas. We have heard today
## particularly about conservation programs and achievements in Europe
and New Zealand. W. H. Drury spoke briefly about experience in eastern North America and F. Salomonsen told us how the bird populations of the Faeroes Islands have been managed for sustained yield.
At least in the North Atlantic, where the history of the bird populations is much better known, the conservation situation has been, and probably still is, very much worse than that now prevailing in the North Pacific. Looking back on 200 years in the North Atlantic, we find that two major marine species have been extinguished, at least one and probably two or three others became endangered, and almost all the seabirds were drastically reduced in numbers (at least in temperate latitudes). Starting in the late 19th century when many species first received effective protection, most showed impressive recoveries, but some have declined again in the last 30 years.
We can learn several lessons from that experience. One is that we can do great damage to seabird populations in a very short time if we do things that cause substantial adult mortality. A second is that seabird populations can recover well with protection and modest management--although most of them, being slow breeders, recover slowly. A third lesson is that in the last 30 years we have caused substantial damage through oil spills, human disturbance at the breeding colonies, chemical pollution, and indirectly by promoting the spread of gulls. Much has been said at the conference about these present-day human impacts. However, with the sole exception of the oil spills which have affected alcids and sea ducks in parts of northwest Europe, it seems to me that the damage caused by human activity in the past 30 years is considerably less than that in the last 30 years of the 19th century.
Another lesson we can learn from the recent experience in other areas is that it is possible to ameliorate some of these adverse human impacts with local, small-scale, and even rather amateurish management activities--for example, protecting seabird colonies from gulls, regulating human visits, and controlling the use of the most toxic chemicals. Our most conspicuous failure is in controlling oil pollution. Although safety precautions imposed on offshore drilling rigs and at shipping terminals have proved reasonably effective in averting major damage to seabirds, attempts to control oil pollution during transportation have been essentially fruitless. Tanker accidents and deliberate discharges from vessels remain the major threat to seabird populations.
Another lesson from other areas is that public education has been very effective in putting pressure behind conservation measures, and is doing so increasingly. At the same time, however, it is resulting in an increase of the disturbances that the birds suffer at their breeding grounds from casual visitors, photographers, and sometimes, well-meaning naturalists.
Finally, in very recent years, there have been encouraging developments in rehabilitating oiled birds, captive breeding, and reintroduction into areas from which they have been depleted. Restoration of seabird populations no longer seems an impossible goal.
Conservation Needs for North Pacific Seabirds
We now know enough about the seabirds of the northern North Pacific to specify in principle what should be done immediately to conserve them. I will not address the institutional arrangements needed for conservation; R. E. LeResche's paper presented a very clear picture of the institutional problems involved in protecting and managing seabirds on an interregional and international basis. I will simply endorse his principal recommendation: that we should try to bring the various responsible agencies together to formulate comprehensive management plans.
On the level at which we as individuals and as a group of biologists can work, we can already make some positive recommendations. The most important is that since prevention of damage is a lot better than cure, measures to avert damage should have the highest priority. We have heard a great deal from the oil industry about the "inevitability" of accidents. One speaker mentioned the "inherent fallibility of man." Well, we are all fallible, but the experience of the last 50 years is that some people are more fallible than others. No oil company has a perfect record, but some have 10 times as many accidents as the best, and some, I believe, have considerably more than 10 times as many. This means, very simply, that it is possible to eliminate most--not all, but most--of the major threats to the seabirds, merely by upgrading the safety performance of the entire industry to that already achieved by its best segments. I suggest that our major challenge in the coming years is to work for effective regulation of the industry: to achieve regulations which will decisively penalize bad performance and as decisively reward care.
Perhaps the second priority in conservation is to protect and manage the existing breeding colonies. In most cases protection is legally feasible if we have the will. Most of the major colonies are in remote areas or in public ownership where development and disturbance can be controlled. Management of the breeding populations is less straightforward, however, because we do not know enough about the functioning of this complex biological resource. Seabird populations fluctuate and they have a very long response time, the environment is not constant, we do not understand the dynamics of multispecies communities, and we do not know how they respond either to external changes or to our attempts to manage them. Management will have to be improvisatory for a very long time. We must recognize that effective conservation of a bird population with a 20-year generation time will take at least 20 years to show results.
Another priority task is to control predators. I have been impressed by the evidence we have for major effects of predators on the seabird populations here. I would regard control of predators and management of habitats on some of the major seabird islands as an extremely urgent task.
A longer-term but no less important program is public education. This program has several important aspects: one is to increase public support for political actions and effective regulations to protect seabirds; another is to educate the public about the vulnerability of seabirds and to prevent disturbance or deliberate human destruction.
Another aspect of public education is to develop public interest by making some of the birds more visible. The great problem with this biological resource we have been talking about is that no one knows it is there. Probably half of us did not know how substantial and important a resource it is even 5 years ago. In setting up a large-scale conservation program, we should not make the mistake of basing it only on the most remote and inaccessible colonies, even if these are the most important numerically. Many of the smaller colonies are locally very important, both biologically and for human interest and education. One example given at this conference was the State of Washington's program for conserving what are, by northern Pacific standards, quite small colonies. This program is important and impressive because it is conserving bird populations near people who want to see the birds. We have the same sort of situation in Massachusetts and Maine, where effective protection programs have been established for extremely small seabird colonies. We have learned from these programs that a few hundred birds, or even a few dozen if properly managed, can be of immense educational importance. If human access is carefully managed so that people can see the birds without disturbing them, these programs can generate support for conservation of larger bird populations that may be thousands of miles away where people may never see them.
A Rationale for Conservation
As I have tried to show, we know something about the importance of this biological resource, and we know in outline what we should do to conserve it. But why should we? Almost no one knows the birds are there. We ourselves do not know whether there are 50 million or 250 million birds in the north Pacific Ocean. Who cares if 10 million disappear? If we cannot give a good answer to this question, we might as well go home and study chickadees instead.
To justify spending money on conserving marine birds--or any other natural resources--we must establish their value. Some of the arguments made in this conference for assigning economic values to seabirds have been dangerously weak. The annual value of "muttonbirds" _(Puffinus tenuirostris)_ in the New Zealand markets is about $70,000. Some speakers have tried to argue that seabirds might play some subtle role that we do not yet understand in regulating marine communities--perhaps they weed out the sick fish. The direct economic values that we have specified for seabirds are really not very impressive, even in terms of the costs involved in conserving and studying them. The biggest number we have heard for the value of these seabirds is the amount of money we are spending on surveys.
However, this is not the real issue. In judging the costs and benefits of a conservation program, we should not look just at the value of the birds as meat, or oil, or indicators of pollution. The real issue here, as in all economic problems, is the rational allocation of resources. H. Boyd posed the rhetorical question: "Why should we waste public money on conserving birds when there are so many other things to spend it on?" The question is more properly posed in reverse: "Why should the government waste so much public money on unproductive projects when only a small amount of money can achieve conservation of these birds which some people think are important?"
The fact is that we already know why we should allocate resources to conservation. I believe that we have just been evading the answer. We ought to conserve these birds because many people want them to be conserved.
This is not, as one speaker said, an elite interest. The public, as we well know, is already willing to spend money to conserve natural resources and is increasingly demonstrating that willingness. The public, in fact, is ahead of the administrators and bureaucrats. To appreciate this, we need only look at some of the laws already on the books. The Congress of the United States, in the National Environmental Policy Act of 1969, declared that it was the national policy to "create and maintain conditions under which man and nature can exist in productive harmony, and fulfill the social, economic, and other requirements of present and future generations of Americans." The Marine Mammal Protection Act of 1972 found that "marine mammals have proven themselves to be resources of great international significance, esthetic and recreational as well as economic, and it is the sense of Congress that they should be protected and encouraged to the greatest extent feasible commensurate with sound policies of resource management and that the primary object of their management should be to maintain the health and stability of the marine ecosystem." As these laws have been enacted, their language has become progressively stronger. The Endangered Species Act of 1973 declares as the policy of Congress "that all federal departments and agencies shall seek to conserve endangered species and threatened species and shall use their authorities in furtherance of the purposes of this Act" (P.L. 93-205). It further directs all Federal departments and agencies to carry out conservation programs for the conservation of endangered or threatened species and to insure that their actions do not jeopardize the continued existence of these species or destroy or modify critical habitat.
These references are not only to Federal laws passed by remote politicians who can vote with only a modest responsibility to their constituents. As we have heard, there are many State laws and local ordinances which specify the same kind of thing. All these laws are on the books for a powerful reason: public opinion was behind them. The fact that they have not been enforced and implemented fully means that we have not been doing our job.
In fact, there is no philosophical problem in justifying conservation. What we face is an institutional problem. There is both a public determination that natural resources should be conserved and a public apathy and bureaucratic resistance toward doing it. As concerned biologists, we should be combating this apathy by pointing out that conservation represents a rational allocation of public resources.
Those who do not learn the lessons of history are destined to repeat it. If we study the history of conservation, we find that it developed most rapidly in those countries which mismanaged their natural resources earliest. Within the developed countries there has been a progressive historical trend toward rational use and conservation of natural resources. Conservation of natural resources, in fact, represents the future and, as biologists, it is our duty to promote it.
Economic Feasibility of Conservation
Conservation is cheap. Most of us are accustomed to working on what are essentially shoestring budgets--on the order of $100,000, $10,000, or even $1,000 per year. When we hear of a million dollars as the cost of doing something, we tend to think of it as a lot of money. H. Boyd mentioned a situation on Baffin Island, where it would cost about a million dollars to dispose of mine tailings on shore instead of dumping them into the ocean under a fulmar colony. I do not think a million dollars is very much--certainly not in comparison with the cost of restoring a colony of half a million fulmars.
We heard this morning about the acquisition of Protection Island at a cost of several hundred thousand dollars. It was pointed out that it could have been acquired much more cheaply only a few years ago. Acquisition of habitat is cheap if we do it now compared with what it will cost in a few years or a few decades. Management is cheap. None of us gets paid very much, but each of us could manage several colonies with a couple of students to help us. Wardens are cheap. Surveys are cheap. The cost of conserving seabirds is minuscule in comparison with the amount spent on the exploitation of resources that threatens them, and it is minuscule in relation to the cost of restoring a seabird population after it has been depleted.
It is far cheaper to avoid oiling birds than it is to rehabilitate them and to reestablish them in breeding colonies in the wild. It costs nothing at all to award leases to companies that have a good safety record and to refuse leases to companies with bad records. It costs a little more to maintain good safety practices in drilling and transportation. It does cost more to transport oil in small, double-bottomed tankers with well-trained crews than to transport it in big ships flying flags of convenience, but the cost differential is very small compared to the value of the shipment.
In considering the economics of conservation, we have to weigh the costs of conservation against the value of the resource being exploited. Full-scale development of oil reserves on the Alaskan continental shelf would generate economic values on the order of ten billion dollars per year. Of this total, 0.1% would support a reasonably sized management program for the threatened resources. About 1% of the total, or 12¢ per barrel of oil, would not only support an ample management program but also permit management of many other coastal zone resources. Yet the experience of the last few years has shown that an increase in oil prices of 1% is barely noticed by consumers.
The point I am trying to make is that extracting oil carefully does not cost significantly more than extracting it carelessly. If we can solve the institutional problems--and I do not underestimate the difficulty of doing so--we are not talking about an irrational use of resources. Conservation is feasible; it is worthwhile; it is not expensive; and there is a public demand for it.
Conclusions
Practical conservation is an adaptive process. It is not at present a process that is firmly based in ecological theory. It is one in which we have to start by doing something, see whether it works, and then change our program in accordance with our early experience. I do not believe that we can wait for detailed knowledge of population sizes, or ecology, or demography, or trophic importance, or any other biological attribute of these birds before we start conservation and management. As scientists we do, of course, find it interesting and important to study these things. We should do so; we need to do so; but we should not use our ignorance of detail as an excuse for delaying action. If this seabird resource is worth conserving, we should start now.
Summary
The marine birds of the northern North Pacific Ocean, Bering Sea, and adjacent seas constitute one of the great neglected biological resources of the world.
This resource is impressive in terms of both total numbers (probably of the order of 100 million birds) and species diversity. A number of species are endemic to the area and hence of special interest.
The resource is international in that it includes major populations of migrants from Chile, New Zealand, Australia, Japan, the Soviet Union, and other countries. Several migrant species appear to use this area exclusively in their nonbreeding season and should be included in the list of endemics.
The general relation between the distribution and abundance of seabirds and other marine resources is beginning to be understood. However, comparatively little is known about the distribution of seabirds in winter, and there is a serious dearth of information about breeding success, survival, and demography.
Seabirds in the north Pacific Ocean and adjacent seas are concentrated over the continental shelf and in areas of high biological productivity. Hence they are especially vulnerable to human exploitation.
Seabirds of the northern Pacific Ocean have already been damaged by human activities in the past and present. Experience in other areas shows that seabirds are extremely vulnerable to human activities and their populations are often very slow to recover.
The most important threats to the seabird resource are oil drilling and transportation and introduced predators, especially foxes. Other identifiable threats include mineral exploitation, fishing, ocean dumping of toxic chemicals, and human disturbance, including both hunting and tourism.
Experience in other parts of the world, especially in the North Atlantic, has shown that seabird populations can be protected and restored through modest programs of management and public education. The principal exception has been the failure to regulate discharges of oil at sea, which continue to cause major damage to seabird populations in many areas.
In the North Pacific and Bering Sea areas, the most urgent conservation needs are effective regulation of prospective oil exploitation, control of introduced predators, and public education. Regional management plans should be developed. Public access to bird colonies should be managed carefully to combine protection with public education.
Conservation programs for seabirds can be justified as a response to increasing public demand for rational management of natural resources. Conservation programs are inexpensive in relation to the economic values generated by oil and mineral development. They represent a rational allocation of economic resources.
The following priorities for further study are suggested:
• Study of productivity and demography in a few carefully selected species to provide basic life table data that will permit rapid identification of future changes.
• A base-line census of some carefully selected breeding colonies, including precise photographic surveys that can be used to measure future population changes.
• Surveys of the distribution of seabirds of the North Pacific and Bering Sea in winter, with special emphasis on areas close to shore where birds may be vulnerable to oil pollution.
• Special studies of endemic species.
• Studies of the way in which seabirds locate and use patchily distributed food resources.
The following conservation measures are suggested:
• Adoption of regulations governing exploitation and transportation of oil which would provide strong incentives for safe performance and severe penalties for safety violations.
• A conservation tax of a few cents per barrel of oil to cover the costs of managing the major seabird colonies and to establish a trust fund for restoring depleted populations.
• Equivalent measures for mining and other exploitative industries in the coastal zone with a prospective impact on marine resources.
• Prohibition of dumping of toxic chemicals in biologically productive waters.
• A program to eliminate introduced predators from the Aleutian Islands and from important bird colonies elsewhere.
• Promulgation of effective regulations to protect birds under the Migratory Bird Treaty with Japan.
• Negotiation of migratory bird treaties with other affected countries, including the Soviet Union, Australia, New Zealand, and Chile.
• Acquisition of major unprotected seabird colonies into the national wildlife refuge or other federal landholding systems.
• Formulation of regional and international management plans for localized species, especially endemic species of the Bering Sea.
• Regulation of public access to major seabird colonies.
APPENDIX
Papers and Oral Summaries Presented at the Symposium but Which Do Not Appear in this Publication
Conservation of marine birds of northern North America--the symposium theme, by Nathaniel P. Reed
The marine environment of birds: an overview, by N. Philip Ashmole
Environmental hazards to birds from petroleum development in the Beaufort Sea, by Kees Vermeer [in lieu of a paper on the status of birds in the Beaufort Sea]
Birds of the marine habitat off northwestern North America, by Gerald A. Sanger and James G. King
The pelagic and nearshore birds of the Beaufort and Chukchi Seas, by George J. Divoky and George E. Watson
Dispersal and migratory movements, by George E. Watson, George M. Jonkel, and F. Graham Cooch
Summary of the session "Status of Marine Bird Populations," by David N. Nettleship
Breeding habitat of marine birds, by Gerald A. Bertrand
Exposure of marine birds to environmental pollutants, by Harry M. Ohlendorf, Robert W. Risebrough, and Kees Vermeer[83]
Summary of the session "The Biology and Ecology of Marine Birds in the North," by Hugh Boyd
Summary of the session "Conflicts Between the Conservation of Marine Birds and Uses of Other Resources," by Joseph P. Linduska
Programs and authorities of the United States Government related to marine bird conservation, by Omar Halvorson
Programs and authorities related to marine bird conservation: Canadian Government, by Hugh Boyd
Programs and authorities of the State of Alaska related to marine bird conservation, by Robert E. LeResche
Seabird programs of private organizations, by C. Eugene Knoder
Summary of the session "Programs and Authorities Related to Marine Bird Conservation," by William H. Drury
Conservation of marine birds in Antarctica, by William J. L. Sladen
Seabirds and their conservation in Western Europe, by W. R. P. Bourne
Summary of the session, "Conservation of Marine Birds in Other Lands," by Joseph J. Hickey
FOOTNOTES:
[83] This paper, because of its length, was published separately as _Wildlife Research Report 9_.
U.S. GOVERNMENT PRINTING OFFICE: 1979-681-016/29
TRANSCRIBER'S NOTES
P. 228 the sentence "The factors in Table are largely self-explanatory" was missing the table reference.
Silently corrected simple spelling, grammar, and typographical errors.
Retained anachronistic and non-standard spellings as printed.
Enclosed italics markup in _underscores_.
Enclosed bold markup in =equals=.