[41] Common eider, 2 to 7 h.
[42] No data given.
[43] Indirect evidence that young are brooded this long.
[44] Data from Lack (1968) and Ashmole (1971) unless otherwise noted.
[45] Cullen (1957).
[46] Birkhead (1974).
[47] Speich and Manuwal (1974).
Zoogeography and Taxonomic Relationships of Seabirds in Northern North
America
by
M. D. F. Udvardy
California State University
Sacramento, California 95819
Abstract
The zoogeography and taxonomic relationships
among 42 living and 1 extinct species of marine
birds from the northern and northwestern coasts
of North America are described. Seventeen
species are circumpolar in distribution; 17 are
endemic to Beringia, and 8 have origins in the
North Pacific.
This discussion concerns the northern and western coasts of the
continent, from about the Mackenzie Delta westward and southward to
the mouth of the Columbia River. Besides bona fide seabirds, I include
marine birds that predominantly breed and feed on or around the marine
littoral, but exclude two groups: shorebirds, jaegers, and phalaropes,
which breed inland and move out from the Arctic after an undetermined
postbreeding period; and Anseriformes which become "marine birds" in
their southern winter quarters. What remains is 42 living species
(Table 1).
The Procellariiformes, or tube-nosed seabirds, have a predominantly
southern hemispheric, Gondwanan distribution. The North Pacific basin
is an important feeding ground of several shearwaters (_Puffinus_
spp.) that breed in the South Pacific and subantarctic. Only three
species breed in the area under consideration: the fulmar _(Fulmarus
glacialis)_ and two storm-petrels (_Oceanodroma_ spp.), all of which
are still relatively widespread.
Of the Pelecaniformes, the very successful, worldwide cormorants
(_Phalacrocorax_ spp.)--inland water as well as coastal and
"amphibious" species are on every continent--are ancient Pacific
dwellers, with a high grade of endemism here: Of the two subarctic
species, one _(P. perspicillatus)_ became extinct long ago, and the
other, the red-faced cormorant _(P. urile)_, is very restricted,
and deserves our greatest attention. The pelagic cormorant _(P.
pelagicus)_, Brandt's cormorant _(P. penicillatus)_, and the
double-crested cormorant _(P. auritus)_ are widespread and successful,
extending south of the area here considered; double-crested cormorants
also breed inland and across toward the North Atlantic coast. As
fish-eaters they are often persecuted where coastal fishermen possess
firearms, and thus are sensitive to increasing human influence on the
coasts.
Two species of arctic geese need special attention. The emperor goose
_(Philacte canagica)_ is a Beringean endemic and lives in a very
restricted area of both sides of this sea; its status (endangered?)
is unknown to me. Since the black brant _(Branta bernicla)_ is a
long-range migrant, it is hunted as a game bird at its winter grounds,
and subject to management measures. Whereas the emperor goose is a
unique offshoot of the genus Anser, the Pacific brant is considered a
subspecies; its general distribution is circumpolar.
Five arctic ducks, and one other, constitute the sea ducks of the
area. The common eider _(Somateria mollissima)_, king eider _(S.
spectabilis)_, and the oldsquaw _(Clangula hyemalis)_ are widespread,
and circumpolar or nearly so; hunting and down-robbing in other
parts of the Arctic may provide clues as to their relative tolerance
of primitive or advanced civilization. The spectacled eider _(S.
fischeri)_ and Steller's eider _(Polysticta stelleri)_ are restricted
to the Bering Sea coasts and neighboring High Arctic coasts,
respectively; their status is precarious.
Table 1. _Seabirds in northwestern North America._ (x = breeding,
w = wintering or transient, () = either scarce or restricted
distribution, * = stragglers only, nesting status unclear)
Distribution
---------------------------------------------
|Circumpolar
| |Widespread in North Pacific
| | |North coast of Alaska
| | | |Beringia[48]
| | | | |Aleutian Islands
| | | | | |South coast of Alaska[49]
| | | | | | |Temperate northeast
Species | | | | | | |Pacific coast[50]
_Fulmarus glacialis_ x w x x x w
_Oceanodroma furcata_ x x x x
_O. leucorhoa_ x x x x x
_Phalacrocorax auritus_ x x x
_P. penicillatus_ (x) x
_P. pelagicus_ x x x x x
_P. urile_ x x x
_Branta bernicla_ x x x (w) (w) w
_Anser canagicus_ x w w
_Clangula hyemalis_ x w x x w w w
_Histrionicus histrionicus_ x w w w w w
_Polysticta stelleri_ x x (w)
_Somateria mollissima_ x x x x x
_S. spectabilis_ x x x w (w)
_S. fischeri_ x x
_Larus hyperboreus_ x w x x w w w
_L. glaucescens_ x x x x
_L. occidentalis_ (x)
_L. argentatus_ x w x (x)w
_L. thayeri_ w x w w w w
_L. canus_ x w x x (x)w
_Rissa tridactyla_ x w x x x x w
_R. brevirostris_ x x (x)
_Xema sabini_ x x x w
_Sterna paradisaea_ x w x x x w
_S. aleutica_ x x
_Uria aalge_ x x (x) x x x x
_U. lomvia_ x x x x x x
_Alle alle_ x *
_Cepphus grylle_ x x w
_C. columba_ x x x x x
_Brachyramphus marmoratus_ x (x) x x
_B. brevirostris_ x x x
_Synthliboramphus antiquus_ x x x x x
_Ptychoramphus aleuticus_ x x x
_Cyclorrhynchus psittacula_ x x
_Aethia cristatella_ x x
_A. pusilla_ x x
_A. pygmaea_ x
_Cerorhinca monocerata_ x x x
_Fratercula corniculata_ x x x x x
_Lunda cirrhata_ x x x x x
Total number of nesting species 17 11 15 27 25 24 17
Total number of wintering species 9 4 7 9 9
Grand total 17 20 15 31 32 33 26
The harlequin duck _(Histrionicus histrionicus)_ stands alone without
close relatives. It often breeds far from the sea, but spends the
shortest time--only a few weeks--away from the rocky coast. There
is a year-round population of yearlings in the sea. The drakes
of the nearest breeding pairs at lower latitudes are back to the
sea, abandoning their mates at the breeding stream when the alpine
stream-dwellers are still at sea awaiting the thawing of their breeding
grounds. Harlequin ducks live in large parts of Siberia, from arctic
Alaska to central California and Colorado, and also in the eastern
Arctic. They do not seem to me to be in immediate danger globally,
though perhaps they are locally.
Gulls are a highly successful group of seabirds, and of the eight
species on our coasts the four more southern ones--the western gull
_(Larus occidentalis)_, glaucous-winged gull _(L. glaucescens)_, common
gull _(L. canus)_, and herring gull _(L. argentatus)_--are expanding
wherever civilization creates new scavenging opportunities. Nothing
is said about the populations of the kittiwake _(Rissa tridactyla)_,
black-legged kittiwake _(R. brevirostris)_ and Sabine's gull _(Xema
sabini)_, or of the other two high arctic species (_Pagophila eburnea_,
_Rhodostethia rosea_) which do not nest regularly in the area
considered here.
The arctic tern _(Sterna paradisaea)_ is circumpolarly widespread
and successful, whereas the Aleutian tern _(S. aleutica)_ is a very
restricted Beringean endemic, and its status needs to be exactly known.
Almost one-third of the seabirds in this area are alcids, a family
centered in the North Pacific and, more specifically, in the
Bering Sea. Most species breed in enormous rookeries. Any impact
of civilization is highly detrimental under such circumstances. Of
the four circumpolar species the two _Uria_ guillemots (murres) are
important. The dovekie _(Alle alle)_ is a sparse pioneer of Bering
Strait, as is the black guillemot _(Cepphus grylle)_ on our side of
the Arctic Sea. Its congener, the pigeon guillemot _(C. columba)_, is
common and successful all the way to coastal central California. Of the
remaining 11 species, special attention should be paid to the whiskered
auklet _(Aethia pygmaea)_ of the Aleutian chain; the Kittlitz's
murrelet _(Brachyramphus brevirostris)_ of the eastern Beringean
and southern Alaska coast; and to the widespread, but very sporadic
rhinoceros auklet, or puffin _(Cerorhinca monocerata)_.
To sum up, I have tabulated these 42 species, and indicated whether
modern life-history and population studies are extant:
No. No.
species studied
Procellariiformes 3 2
_Phalacrocorax_ 4 2
Anseres 2 1
Anates 6 --
Lari 9 2
Sterni 2 --
Alcidae 16 7
Total 42 14
Thus, 28 species await studies preliminary to, and highly necessary
for, conservation measures.
Seventeen species of marine birds are spread either circumpolarly
around the northern perimeter or along the north-south coasts of the
Laurasian continents. Four of these are of the High Arctic (_Branta
bernicla_, _Somateria spectabilis_, _Xema sabini_, _Alle alle_);
another seven penetrate the Bering Sea as well (_Fulmarus glacialis_,
_Somateria mollissima_, _Clangula hyemalis_, _Larus hyperboreus_,
_Rissa tridactyla_, _Sterna paradisaea_, _Uria lomvia_); and six are
panboreal-subboreal, widespread in their distribution--_Oceanodroma
leucorhoa_ (extends far south), _Histrionicus histrionicus_, _Larus
argentatus_ (widespread latitudinally), _L. canus_ (also inland), _Uria
aalge_, and _Cepphus grylle_.
Seventeen species of marine birds are endemic to Beringia: _Anser
canagicus_, _Polysticta stelleri_, _Somateria fischeri_, _Rissa
brevirostris_, and _Aethia pusilla_ (and the extinct _Phalacrocorax
perspicillatus_); _P. urile_, _Sterna aleutica_, _Aethia pygmaea_,
_A. cristatella_, and _Cyclorrhynchus_ extend westward to the Sea of
Okhotsk, as do _Brachyramphus brevirostris_ and _Larus glaucescens_,
which also extend eastward; and _Phalacrocorax pelagicus_, _Cepphus
columba_, _Fratercula corniculata_, and _Lunda cirrhata_ are
amphipacific species in Beringia.
Eight species of marine birds are associated with the North Pacific.
Four are found on both sides of the ocean--_Oceanodroma furcata_,
_Brachyramphus marmoratus_, _Synthliboramphus antiquus_, and
_Cerorhinca monocerata_ (very disjunct). The four others occur on only
the North American side--_Phalacrocorax auritus_ (also inland), _P.
penicillatus_, _Larus occidentalis_ (albeit barely), and _Ptychoramphus
aleuticus_.
Finally, one species, _Larus thayeri_, is endemic at the central
Canadian Arctic, extending westward into the area here considered.
FOOTNOTES:
[48] Beringia comprises the islands and coasts of the Bering Sea.
[49] South coast of Alaska extends from the tip of the Alaska Peninsula
to Glacier Bay.
[50] Temperate northeast Pacific coast extends from Glacier Bay south
to the mouth of the Columbia River.
CONFLICTS BETWEEN THE CONSERVATION OF MARINE BIRDS AND USES OF OTHER
RESOURCES
Social and Economic Values of Marine Birds
by
David R. Cline[51] and Cynthia Wentworth
U.S. Fish and Wildlife Service
Anchorage, Alaska
and
Thomas W. Barry
Canadian Wildlife Service
Edmonton, Alberta, Canada
Abstract
Throughout history, marine birds have provided
tangible and intangible benefits to human
societies. Unregulated exploitation of some
species by explorers, mariners, and colonists
led to the extinction of the great auk
_(Pinguinus impennis)_ and near extinction
of others, including the Bermuda petrel
_(Pterodroma cahow)_ and the North Pacific
albatrosses (_Diomedea_ spp.). Marine birds
continue to provide commercial, subsistence,
recreational, scientific, and educational
values to people of many nations, while playing
critical roles in the economies of the world's
oceans.
Annual harvest of slender-billed shearwaters
_(Puffinus tenuirostris)_ known as
"muttonbirds" in Australia, sooty tern _(Sterna
fuscata)_ eggs in the Caribbean, murres
(_Uria_ spp.) and eiders (_Somateria_ spp.)
in Greenland and the Soviet Union, and guano
in Peru and Africa represent the principal
commercial uses of marine birds and their
products. Residents of the Faeroes Islands and
thousands of native people in Greenland and
arctic Canada and Alaska use various species
for subsistence. The annual rituals of bird
hunting and egg gathering are deeply ingrained
in the sociocultural traditions of these
peoples and continue to be important to their
social welfare.
Most countries of the world are currently
providing at least some protection to their
marine bird resources. However, the destruction
of bird habitats by man's developments and
the contamination of marine environments by
industrial pollutants are posing increasingly
serious threats to many species. If managed and
used in accordance with scientific principles
of sustained yield, some of the more abundant
species of marine birds can continue to provide
long-term social and economic benefits to man.
Increasing numbers of people are expending
considerable sums of money to reach marine
bird viewing areas off the coasts of North
American States and Provinces. Preliminary
evidence indicates such nonconsumptive pursuits
are contributing significant amounts of money
to regional economies and helping businessmen
earn a living. An accurate evaluation of both
biological and economic impacts resulting from
these nonconsumptive activities is urgently
needed.
The possibility of establishing an excise tax
on designated outdoor recreational equipment
appears to hold considerable potential for more
adequately funding marine bird programs, as
well as those for other nongame wildlife.
Greater citizen involvement in sociopolitical
processes will, to a large extent, determine
the success of marine bird conservation
programs. Sound conservation legislation
that insures adequate protection of habitat
and provides for enlightened and innovative
thrusts in conservation, education, research,
management, and law enforcement will help
insure the survival of all species of marine
birds and, in turn, provide social and economic
benefits to people across generations. #/
In its 17 March 1975 issue, _Time_ magazine reported battalions
of observers from all over the country flocking to Salisbury,
Massachusetts, armed with telescopes, cameras dwarfed by huge telephoto
lenses, sketch pads, and binoculars. There, 1,500 strong the first
weekend alone, they took up vigil along the seawall of the Merrimack
River. A local businessman circulated among the chilly bird-watchers
with free coffee and hot chocolate, while handing out a pamphlet
advertising his restaurant.
The cause of the commotion was the appearance of a single, unassuming,
pigeon-like seabird called a Ross' gull _(Rhodostethia rosea)_,
almost never seen south of the Arctic Circle and never before in the
contiguous 48 States. Time stated that "for those who care about such
matters the event was as electrifying as the descent of a Martian
spaceship."
Meanwhile, far above the Arctic Circle at Point Barrow on the Arctic
Ocean, Eskimo hunters probably puzzled at the strange ways of the white
"birdmen," as they recalled the savory dishes Ross' gulls provided many
of them during the previous fall hunting season. This particular gull
is considered a delicacy by the Eskimos, and the birds are actively
sought each year as they fly near shore during their fall wanderings
from Asian breeding grounds.
Perhaps this dichotomy of people's interests in a single species is
indicative of the broad spectrum of social and economic values man
derives from marine birds. Perhaps, too, it represents the challenge
that wildlife professionals, administrators, and citizen conservation
leaders face in today's complex world in striving to sort out
priorities in allocation of such common property (amenity) resources
among beneficial users.
As with the Ross' gull, socioeconomic values of marine birds involve
both consumptive and nonconsumptive uses. Consumptive uses may provide
socioeconomic values in the form of meat, eggs, oil, feathers, down,
and guano. Cultural and recreational benefits may also be involved.
Nonconsumptive uses benefit the tourist and recreation industries
as well as providing less tangible social values, such as esthetic
appreciation and environmental education and scientific study
opportunities.
In this paper we examine some social and economic indicators that are
believed to demonstrate people's growing awareness and interest in
marine birds. These indicators involve a broad spectrum of values and
illustrate the critical need for adoption of a strong North American
marine bird conservation program.
Historical Perspective
Since earliest times, marine birds have accompanied the evolution of
human societies in coastal and insular environments of the world.
Their social value is in part recorded in kitchen middens of ancient
campsites and villages. From the time man first inhabited the seacoasts
and ventured out in ships, the company of seabirds has added life and
inspiration to what otherwise would be a bleak and desolate landscape.
Fishermen long ago learned to use seabirds to show them where the rich
fishing grounds were located, and the cries of birds were often used to
guide mariners away from dangerous cliffs during foggy weather.
At the time of the first contact with Europeans, native peoples of
arctic Canada and Alaska reportedly took birds with bolas, snares,
spears, arrows, and nets; they herded flightless waterfowl and gathered
eggs as well. Brandt (1943) said that Alaskan Eskimos would have been
destitute if eiders (_Somateria_ spp.) had not been available for food
and clothing, and Ekblaw (1928) believed the dovekie _(Plautus alle)_
saved the polar Eskimo from extinction.
Marine birds have often served as an emergency food supply for
explorers, sailors, and others: according to Tuck (1960) "The accounts
of early arctic explorers and marooned whalers describe many instances
in which starvation was averted by eating murres" (_Uria_ spp.).
One burrowing petrel of Australia was given the title "the bird of
providence" because it saved the lives of shipwrecked mariners and
convicts when supply ships from Sydney failed to reach them between
March and August of 1790 (Serventy 1958).
Marine birds have also been taken because of the economic values of
their feathers and oil. When economic overutilization has occurred,
entire species were sometimes totally destroyed. This in fact happened
to the great auk _(Pinguinus impennis)_. When Jacques Cartier visited
the Funk Islands off Newfoundland in May 1534, he and his crew filled
several barrels with great auks and salted them down for future
consumption. So severe was the slaughter in the next 3 centuries
that the species became extinct in its known breeding haunts, which
originally extended from Newfoundland through Greenland and Iceland, to
the Hebrides. The last one was killed at a stack rock off Iceland in
1884 (Lockley 1973).
Other species have been almost totally destroyed. Colonization of
Bermuda by Spain in the 17th century resulted in the near annihilation
of the Bermuda petrel _(Pterodroma cahow)_ there. Ships' crews found
the birds to be fat and delicious, and they dried and salted those that
could not be eaten fresh. Today, only about 20 breeding pairs remain,
and are under strict protection by the Bermudan government (Lockley
1973).
The North Pacific albatrosses (_Diomedea_ spp.) were nearly
exterminated by Japanese feather hunters near the end of the 18th
century. The short-tailed albatross _(D. albatrus)_ was also nearly
wiped out at its breeding colonies west of the Hawaiian Islands (Bourne
1972).
Other species that were carelessly exploited for their meat and plumage
in the past, but which have since regained their numbers, include
the fulmar _(Fulmarus glacialis)_ on St. Kilda Island in the North
Atlantic; and the North Atlantic, South African, and Australian gannets
(_Morus bassanus_, _M. capensis_, and _M. serrator_) (Bourne 1972;
Lockley 1973). In some instances entire breeding colonies of a species
have been destroyed while others have survived. On the Abrothos Islands
in western Australia, for example, large nesting colonies of sooty
terns _(Sterna fuscata)_ and common noddies _(Anous stolidus)_ appear
to have been wiped out on Rat Island by indiscriminate "egging" for
food, whereas similar-sized colonies survive on other islands, where
they are now controlled by the Fisheries and Fauna Department (Serventy
et al. 1971).
Historically, it has probably been man's unregulated harvest of marine
birds that has been the primary cause of their destruction. Generally,
the loss of a species because of unregulated harvest is no longer
a matter of major concern, because most countries of the world are
providing at least some protection for their marine birds. However,
other factors such as habitat destruction and contamination of the
marine environment by industrial pollutants are posing increasingly
serious threats to many.
Social and Economic Indicators
Economic indicators concerning consumptive uses of wildlife, including
marine birds, are frequently misunderstood. In a dollar-oriented and
over-consumptive society like ours, economic values are usually seen as
being in conflict with esthetic values. "Economic use" usually conjures
up images of man's overutilization and, hence, long-term depletion
of wildlife resources. However, when speaking of economic use, it is
important to distinguish between such overuse and sustained-yield
management.
Although both types of use have provided economic benefits over the
years, overharvest that results in long-term resource depletion is not
usually the most or best economic use in the long run; obviously a
"harvest" cannot be sustained at a given level when the resource base
is constantly being depleted. On the other hand, when certain species
of marine birds are used in accordance with principles of sustained
yield, they can provide long-term economic values to society in
conjunction with the social, esthetic, and intangible values that their
preservation insures. Of course, for many species esthetic values far
outweigh economic ones derived through commercialization.
_Commercial Uses_
Muttonbirds
The muttonbird industry of Australia is an excellent example of the
commercial use of marine birds on a sustained-yield basis. Fledgling
Tasmanian muttonbirds, or slender-billed shearwaters _(Puffinus
tenuirostris)_, are commercially harvested each year from their
colonies on islands of Bass Strait, mainly in the Flinders Island
group.
These muttonbirds are marketed as fresh or salted "Tasmanian squab."
Various by-products, including oil, body fat, and feathers, are also
sold. In 1968, a total of just under one-half million young birds were
taken. Prices to the producers varied from $12 to $14 (Australian
dollars) per hundred salted birds and $16 per hundred fresh birds.
Stomach oil brought 75¢ per gallon. Assuming the average price per
hundred birds to be $14, the meat alone was worth about $70,000 per
year to the producers. The retail value was of course much higher.
Although the muttonbird harvest is no longer the mainstay of the
Flinders Island economy, according to Serventy (1969) it is still a
picturesque and important annual social event.
Serventy et al. (1971) believed the commercialization of the muttonbird
preserved its numbers: "Had there been no vested interests to preserve
the 'birding islands' as such, many of them would in the course of time
have been 'improved' as sheep stations and the shearwater populations
would have declined and vanished."
Sooty Terns
The Caribbean is the home of the world's most important wild egg
producer--the sooty tern. In some years about 2 million sooty tern eggs
from the Seychelles and 0.6 million from Morant and Pedro bays have
reached Caribbean markets (Tuck 1960).
Eiders and Murres
Although the shooting of birds is not as important economically to
Greenland's approximately 50,000 residents as are sealing, whaling, and
fox hunting, the harvest of seabirds is an ancient tradition that still
means production of an important food source that the many Greenlanders
could not exist without. About 30 species of marine birds are harvested
for human consumption, eider ducks and murres being by far the most
important. In west Greenland about 750,000 birds (equivalent to about
825 tons of meat) and 10,000 eggs are harvested annually. Murres
constitute the main dish in summer at small coastal outposts with
access to rookeries. Great quantities are also dried and salted for
use in winter. Murre canneries at Upernavik have supplied southern
cities with the frozen meat of about 25,000 to 30,000 murres annually.
However, this commercial activity would be prohibited by a proposed new
Greenland game law (Salomonsen 1970).
Banding has shown that about 22% of Greenland's eider population,
or about 150,000 birds, is shot annually. Collecting of eider eggs
is now prohibited except in the Thule District, where 10,000 are
taken annually. Eider down is still collected from nests for sale to
a trading company for the manufacture of much demanded eider-down
coverlets (Salomonsen 1970).
A growing human population, the widespread use of modern firearms, and
the increasing use of speedboats in hunting have resulted in serious
declines in many of Greenland's marine bird populations. The Greenland
government has demonstrated its concern by instituting protective
measures in response to Danish expert advice. For example, the common
puffin _(Fratercula arctica)_ was given 10 years of total protection
in 1961 after bird numbers had seriously declined as a result of
over-harvesting of the birds and their eggs (Lockley 1973). This
protection was extended in 1970. Also, it is now illegal to discharge
firearms at most marine bird rookeries in Greenland.
With protection of bird habitats from human intrusion and toxic
environmental pollutants, adequate enforcement of sound conservation
laws, greater efforts in conservation education, and scientific
regulation of harvests, Greenland's valuable marine bird resource could
probably withstand intensive utilization indefinitely (F. Salomonsen,
personal communication). Salomonsen has been quick to point out,
however, that people should not be encouraged to believe that the value
of seabirds for food is the only reason they should be saved.
Although several species of marine birds serve as sources of food in
the Soviet Union, down of eider ducks and eggs of murres are considered
to be the most important to the economy. These birds are referred to as
trade birds due to their commercial importance (Belopol'skii 1961).
Guano
Peruvian guano beds are currently being managed on a sustained-yield
basis; the harvest, as in the days of the Incas, depends entirely on
the amount of guano deposited each year. Conservation and management
policies have resulted in a steady increase in the amount extracted,
from around 20,000 tons in 1900 to over 200,000 tons in 1971 (Lockley
1973).
The islands off south and southwest Africa are also commercial
producers of guano. The annual yield from these breeding colonies
averaged 3,971 tons in the 12-year period, 1961-72. In 1969, guano
brought 4.75 Rands (equivalent to $7.11) per 200-pound bag. South
African gannets are apparently depositing guano that is worth twice as
much as the fish they consume to produce it (Jarvis 1971).
_Indirect Commercial Benefits_
Marine birds also play significant roles in the economies of the
world's oceans, where algae, invertebrates, fish, seabirds, mammals,
and man interact in complex ways. The bioenergetics and nutrient
cycling in ocean ecosystems is even less well understood than the
contributions seabirds make to man's dollar economies.
Sanger (1972) has conservatively estimated that in the subarctic
Pacific region alone, birds consume from 0.6 to 1.2 million tons of
food and return from 0.12 million to 0.24 million tons of feces each
year.
Marine bird excrement is especially rich in nitrates and phosphates,
which phytoplankton, the basis of ocean food pyramids, requires. Marine
birds then, at least to some extent, help to sustain the northern
commercial, recreational, and subsistence fishing industries. The
fisheries in turn sustain seals and certain other mammals which are
also essential elements of northern subsistence and recreational
economies. Thus, marine birds contribute economic benefits indirectly
as well as directly by serving as critical links in ecosystem food
chains (Tuck 1960).
_Subsistence Uses_
The use of marine birds and their products does not have to be
commercial to be economic. Economics is the science of the allocation
of scarce resources. Any resource, regardless of whether it is bought
or sold, has value to people and is therefore an economic commodity.
Thus, any society has an economy whether or not it uses cash, and when
the meat, feathers, or oil of marine birds are used, the birds have
economic value. The problem, of course, is that of trying to determine
just what this value is when a cash medium does not exist.
One of the ways to estimate this value is to assign implicit gross
dollar values to seabirds, based on what it would cost to replace
products derived from them with store-bought items of a similar, or
substitutable, nature (this is a gross rather than a net value because
it does not include the cost of guns, ammunition, transportation, etc.,
required to harvest and process the resource).
There have been many occasions in the past when it would have been
physically impossible to find substitutes for seabird products. In such
cases, and where seabirds may well have meant the difference between
life and death, the economic value of the resource could be considered
a plus infinity.
There are probably few, if any, places in the world today where people
would starve if they could not obtain marine birds. However, there are
still many situations where available substitutes are poor, or very
expensive. And there are others where, even though the birds are no
longer necessary for economic survival, they are still very important
in terms of sociocultural traditions. According to Tuck (1960),
"Wherever a wild animal is important to the economy of a people, its
capture and use become part of the tradition of that people." Thus,
while economic values can be measured in terms of substitutable
store-bought foods, social and cultural values cannot be. To force
complete dependence on a people by flying in foods from "Outside" is
often socially intolerable because it tends to remove pride, a sense of
worth, and therefore the reasons for living.
Marine birds have served as important sources of food in the Faeroes
Islands for centuries, the puffin being unquestionably the most
valuable. Williamson (1945) reported that in a good year the total
puffin catch may be between 400,000 and 500,000. In addition, as
many as 120,000 murres are snared or shot annually by the Faeroese,
and at least twice that many eggs are taken and Tuck (1960) stated,
"The economic necessity of 'fowling' in the Faeroes has by virtue of
long centuries of usage become part of the national life, affecting
folklore and customs, and providing outlets for the sporting instinct
inherent in the people." A Faeroese guidebook even suggests that its
importance to the Faeroese culture has been in no way diminished by
the influence of modern civilization. Current Faroese game laws appear
to be effective in assuring a sustained yield of marine birds while
guaranteeing their long-term survival.
Seabirds and their eggs constitute a small, but still very important,
part of the total diet of the Eskimos and Indians living along the
Arctic coast of the Northwest Territories and Alaska. In spite of
the many changes occurring in the North, there is, even for the wage
earner, a strong psychological attachment to the land and sea and
the free life it represents. In spring, the release from the long
monotonous winter is marked by the rites of ratting, fishing, sealing,
whaling, or marine bird hunting and egg gathering, according to village
tradition.
For those living off the land in such remote coastal outposts as Sachs
Harbor on Banks Island, Holman Island on the Mackenzie Delta, Point
Hope and Point Barrow in northern Alaska, Inalik on Diomede Island in
the Bering Strait, or Hooper Bay on the Yukon-Kuskokwim Delta, the
spring marine bird hunt represents a change of diet and activity. It
offers opportunity to renew age-old traditions and continues a cultural
bond among those confined to jobs in the settlements--vacationing and
absenteeism from jobs and schools are always highest during late May
and early June.
Marine birds yield between a few grams and 2 kg of meat, depending on
the species. Usually the birds are either consumed soon after they are
taken or stored in an icehouse for use throughout the summer. Most
often the meat is cooked into a soup or stew with rice, noodles, and
onions. A few birds may be dried or salted so that they can be used for
special holiday feasts during the winter. Sometimes feathers are saved
for the manufacture of parkas, ceremonial fans, and masks. In some
areas of the Yukon Delta, goose and duck down is still saved and used
in quilts that can be found in nearly every home. In the spring 1975
issue of the catalog of a Seattle, Washington, outfitter, down quilts
for single beds were listed at $95. Thus, there is a substantial cash
savings by home manufacture of such items.
The Yukon Delta in western Alaska is the area where the use of marine
birds is most extensive and significant. Klein (1966) provided harvest
data by village for the entire area and showed that, in general, geese
were more important than ducks, representing about two thirds of the
take in both the spring and the fall. The average numbers of ducks
(mostly pintails, _Anas acutus_) and geese (primarily white-fronted
geese, _Anser albifrons_); emperor geese, _Philacta canagica_; cackling
Canada geese, _Branta canadensis minima_; and black brant, _Branta
nigricans_, taken per household were 77 by the Yukon River villages,
69 by the Kuskokwim River and tundra villages, and 94 by the Bering
Sea coastal villages. Although eggs gathered by Yukon River villagers
averaged less than a dozen per household, Kuskokwim people took about 3
dozen and coastal people about 6.5 dozen on the average. Eggs of black
brant and cackling Canada geese were especially favored, but even those
of small passerines were acceptable. The average size of households for
all areas was believed to be between 5.5 and 6.5 persons.
A 1968 survey of waterfowl taken in the Mackenzie Delta region, made
by the Canadian Wildlife Service, showed an average take per household
of about 70 birds, a figure comparable to that for the Yukon Delta. In
the Mackenzie region, however, ducks were more important than geese,
representing about 60% of the harvest.
More recent data on Alaska waterfowl harvest per household is available
for other coastal regions. Data provided by two regional native
corporations for the Joint Federal-State Land Use Planning Commission
for Alaska in 1973 showed an average per-household waterfowl harvest
of 33 ducks and geese for Kotzebue area villages, 68 for Norton Sound
villages, 24 for northwest Seward Peninsula villages, and 37 for St.
Lawrence, Diomede, and King Island villages.
A 1974 subsistence survey carried out jointly by the University of
Alaska and the Bristol Bay Native Corporation showed that, in 20
Bristol Bay villages, 57% of the households harvested waterfowl. The
average kill was 32 birds per household.
Eider ducks are the most important marine birds taken by residents
of Barrow, Alaska. Johnson (1971) interviewed 31 adult hunters
with average kills of 88 birds per hunter. Barrow people also take
substantial numbers of geese at Atkasook, a summer camp on the Meade
River 80 miles southeast of Barrow.
Point Hope, Alaska, villagers also favor eider ducks above all
others. Pederson (1971) indicated that each household that hunted
took about 150 eiders in the summer of 1971. Each summer, Point Hope
and Kivalina residents travel to the Cape Thompson and Cape Lisburne
cliffs to gather murre eggs. Both Pederson (1971) and Kessel and Saario
(1966) showed an average harvest of 5 to 10 dozen eggs per household
(equivalent in weight to 10 to 20 dozen chicken eggs).
To our knowledge, there is no available evidence to indicate that the
number of migratory birds taken in the North in spring and fall is a
significant factor in the survival of a particular species. The birds
are, however, a significant factor in the economy and culture of the
people of the Mackenzie Delta region and much of coastal Alaska. This
may not always be true, for their social and economic conditions are
changing rapidly.
With the native birthrate twice the national average and with hunting
technology improving yearly, the day will undoubtedly come when
marine birds and other wildlife resources are not able to withstand
intensified harvest pressures without more regulation and control. An
obvious need exists for government conservation agencies to work more
closely with the native people of northern regions in conservation
education and development of sound harvest regulations.
_Recreational Uses_
No attempt was made in this evaluation to affix dollar values to
every marine bird enjoyed by recreationists. Goldstein (1971), in his
economic study of wetlands, found it impossible to fix the value of the
production and harvest of migratory waterfowl in Minnesota.
The amount of money spent by recreationists in seeking enjoyment from
marine birds does not measure the values they derive; it measures
only their costs to participate in such ventures. The analogy that
could be made is that the value of a diamond is equal to the cost
of mining it. Nevertheless, expenditure data for services and goods
provided by air-taxi and charter boat operators and merchants selling
bird guides, binoculars, and other outdoor recreational equipment are
useful indicators in establishing the secondary or indirect benefits of
recreational activities associated with marine birds.
The normal economic concept of net benefits from marine bird recreation
would include only those accruing to individuals who provide goods and
services to the recreationists, gross revenues minus the costs (Wollman
1962; Pearse and Bowden 1969). This economic return, however, in no way
measures direct benefits of marine bird resources to the recreationists.
Another important consideration in evaluating recreational use of
marine birds is to recognize that many of the nonparticipants either
value the option of being able to take advantage of them in the future,
or simply believe that the availability of such resources benefits
society (Stegner 1968). Such benefits are difficult, if not impossible,
to quantify yet may be exceedingly important due to the uniqueness of
the marine bird resource and because many decisions affecting it may
prove irreversible.
Increasing numbers of bird enthusiasts throughout North America are
discovering the excitement and pleasures derived from visiting marine
bird rookeries. As pointed out by Sowl and Bartonek (1974), and as
anyone can attest who has ever had the privilege of watching the antics
of tufted puffins _(Lunda cirrhata)_ near their colonies on a day when
the sun is obscured and the air buoyant, watching seabirds is fun.
We have found that organizations and businesses in practically
every North American coastal State and Province, from Nova Scotia
to Florida and Alaska to California, are busy scheduling boat or
airplane excursions to marine-bird viewing areas off their shores.
The Alaska and Washington State ferry systems have for years been
providing passengers opportunity to enjoy seabirds of the North Pacific
coast. Audubon chapters in San Diego, Los Angeles, Monterey, Seattle,
Anchorage, and other cities sponsor annual excursions to seabird
colonies.
In 1975 a charter airline service in Anchorage, Alaska, booked 530
people in 51 tours to fly to the Pribilof Islands in the Bering Sea
to view the outstanding seabird and fur seal colonies there. Included
in the bookings were three National Audubon Society International
Ecology Workshops, the Massachusetts Audubon Society, the National
Wildlife Federation, and Canadian Nature Federation. Participants paid
from $1,500 to $2,000 for these tour packages to Alaska. At $300 to
$380 per person, depending on the length of the excursion, the air
charter service grossed about $160,000 from these tours (Reeve Aleutian
Airways, personal communication).
Fairweather Outings, a small cruise business based in Sitka, Alaska,
takes people on wilderness excursions in the west Chichagof-Glacier
Bay area of the southeastern part of the State. The seabird rookeries
are one of the principal attractions for the 90 people taking these
trips each year. Over one-third of the clientele has been from outside
Alaska; thus their dollars are new dollars to the State's economy.
Fairweather Outings grossed about $11,000 in 1974 (Charles Johnstone,
personal communication).
These examples illustrate how seabirds, both directly and indirectly,
help small coastal businessmen earn a living. It is also important to
recognize that the multiplier effects generated by the expenditures
in all of the above examples ripple through the regional and State
economies.
Despite the great social and economic significance of such activities
along our coasts, apparently no attempt is being made to determine
the number of people involved in such pursuits and how much they are
spending. A study of the phenomenon would undoubtedly produce startling
results.
The Wildlife Management Institute (1975) revealed that the national
estimated value of manufacturers' shipments in 1972 was $157 million
for camping equipment, $5 million for binoculars, and $19.9 million for
bird feed. Sales of wild bird feed have been increasing 5 to 10% per
year recently. These are all economic indicators of recreation trends
of which enjoyment of marine birds is a part.
A major use of photographic equipment and related products and services
is in the natural and scenic areas of the nation. Manufacturers'
shipments of photographic equipment, and photofinishing, were valued
at $2.3 billion in 1972. A 5% excise tax on these items would have
generated nearly $118 million (Wildlife Management Institute 1975).
Since inadequate funding plagues most nongame management initiatives,
the Wildlife Management Institute (1975) recommended that Congress
authorize a matching grant-in-aid program to benefit nongame fish and
wildlife. Funds would be obtained from new manufacturers' excise taxes
on designated outdoor recreational equipment to initially yield at
least $40 million annually.
The Executive Committee of the International Association of Game, Fish
and Conservation Commissioners and the Council of the Wildlife Society
have already endorsed model legislation for a State program for nongame
wildlife conservation (Madson and Kozicky 1972). We urge that these
proposals be given serious consideration in terms of future funding of
marine bird conservation programs in North America.
It is encouraging to note that several States, including Washington,
Oregon, and California, have recently initiated nongame wildlife
programs that have resulted in substantial benefits to their citizens.
The California legislature, for example, enacted a law in 1974 to
provide a means for individuals and organizations to donate funds for
supporting nongame species management. The California Department of
Fish and Game has increased its nongame staff and appointed a citizen
Nongame Advisory Committee to help develop and implement nongame
programs.
Because most species of marine birds are not hunted by sportsmen
in North America, this increased emphasis on nongame species may
eventually benefit research and management programs for seabirds
substantially.
_Scientific Research_
Even now, marine-bird research studies and inventories require the
expenditure of several million dollars annually along our coasts.
In Alaska a multimillion dollar Federal effort has been initiated
to assess the environmental risks of developing offshore petroleum
potential in the Gulf of Alaska and five other key areas of the
State. These areas represent 60% of the nation's total continental
shelf and support some of the largest marine-bird populations in
the world. The program to examine life-forms and the physical
environment of the petroleum lease areas will require 4 to 5 years to
complete. Approximately $1.5 million has been allocated to conduct
an environmental assessment of marine bird resources in the first 18
months alone.
The U.S. Fish and Wildlife Service is spending about $40,000 to
determine the seasonal occurrence, density, and distribution of marine
birds in coastal waters adjacent to new national wildlife refuges in
Alaska being proposed pursuant to the Alaska Native Claims Settlement
Act of 1971, and almost $200,000 to study and manage migratory
birds--including marine birds--on existing refuges.
Although generated by external events (including requirements pursuant
to the National Environmental Policy Act of 1969) rather than by the
resources themselves, these expenditures at least indirectly reflect a
social concern for the welfare of marine birds.
_Citizen Involvement (Social Indicator)_
Another encouraging aspect of seabird conservation and its meaning
to society is the increasing involvement of citizens in the issue.
Although agencies have not been as responsive as many would like,
administration of government at all levels has been shaken and
stimulated by citizen participation. As Russell W. Peterson, Chairman
of the Council on Environmental Quality, has stated, "Citizen action is
the essence of democracy. Citizen movements should be encouraged and
expanded. The involvement of people is necessary to counterbalance the
disproportionate influence of the professional lobbyists and public
relations operators hired to further the special interests of their
clients." Mr. Peterson further emphasized that government thrives
much better on citizen concern and attention than on indifference and
neglect.
Therefore, it is highly significant that the Pacific Seabird Group
has many nonprofessional, as well as professional, members and
that the 1975 International Symposium on Conservation of Marine
Birds of Northern North America had strong citizen involvement and
participation. As everyone recognizes, nothing works in government
unless people, be they doctors, lawyers, college professors, students,
environmentalists, or Indian chiefs, make it work.
Educators must upgrade training in environmental sciences so that an
environmental awareness (conservation ethic) is instilled in young
people. In this regard, an Alaskan bird study program proposed for
Alaska schools by J. G. King, Jr., of the U.S. Fish and Wildlife
Service in 1962 deserves close scrutiny. This highly innovative and
practical environmental education proposal apparently arrived before
its time, for nothing was ever done to institute it. Possibly, now
would be a good time to give it a closer look.
Conclusions
Success in more adequately recognizing and using social and economic
indicators to strengthen and broaden seabird programs will depend
on the ability of the resource management agencies to blend the old
with the new. It is obvious to most that new alignments, programs,
authorities, and sources of funds are needed, but by themselves,
they will not be enough to overcome the continuing massive losses of
wildlife habitat due to population growth and technological impacts
resulting from various developmental programs.
No marine bird programs will be successful without a strong political
base. If this is to be assured, resource agencies must be more
responsive to the needs of both consumptive and nonconsumptive users
and involve them in their programs from early in the planning process.
Because marine birds and the natural environments they inhabit are
jointly valued over time and are jointly owned, it is important to
ask not only what is efficient from the point of view of the present
generation but also what is equitable across generations.
References
Belopol'skii, L. O. 1961. Ecology of sea colony birds of the
Barents Sea. (Transl. from Russian.) Israel Program for
Scientific Translations, Jerusalem. 346 pp.
Bourne, W. R. P. 1972. Threats to seabirds. Int. Counc. Bird
Preserv. Bull. II:200-218.
Brandt, H. 1943. Alaskan bird trails: adventures of an expedition
by dogsled to the delta of the Yukon River at Hooper Bay. Bird
Research Foundation, Cleveland, Ohio. 464 pp.
Ekblaw, W. E. 1928. The material response of the polar Eskimo to
their far arctic environment. Ann. Assoc. Am. Geog. 17(4):147-195.
Goldstein, J. H. 1971. Competition for wetlands in the Midwest: an
economic analysis. Resources for the Future, Inc., Washington,
D.C. 105 pp.
Jarvis, M. J. F. 1971. Interactions between man and the South
African gannet. Biol. Conserv. 3(4):269-273.
Johnson, L. L. 1971. The migration, harvest and importance of
waterfowl at Barrow, Alaska. M.S. Thesis. Univ. of Alaska,
Fairbanks. 87 pp.
Kessel, B., and D. Saario. 1966. Human ecological investigations at
Kivalena. Pages 969-1039 _in_ N. J. Wilimovsky and J. N. Wolfe,
eds. Environment of the Cape Thompson region, Alaska. U.S.A.E.C.,
Div. Tech. Inf., Oak Ridge, Tennessee.
Klein, D. R. 1966. Waterfowl in the economy of the Eskimos on the
Yukon-Kuskokwim Delta, Alaska. Arctic 19(4):319-335.
Lockley, R. M. 1973. Man and seabirds. Pages 74-90 _in_ R. M.
Lockley. Ocean wanders: the migratory seabirds of the world.
Stackpole Books, Harrisburg, Pennsylvania.
Madson, J., and E. Kozicky. 1972. A law for wildlife: model
legislation for a State nongame wildlife conservation program.
Winchester-Western Division, Conservation Department, East Alton,
Illinois. 20 pp.
Pearse, P. H., and G. K. Bowden. 1969. Economic evaluation of
recreational resources: problems and prospects. Trans. N. Am.
Wildl. Nat. Resour. Conf. 34:283-293.
Pederson, S. 1971. Status and trends of subsistence resource use at
Point Hope. Pages 37-89 _in_ B. MacLean, ed. Point Hope project
report. Univ. of Alaska, Fairbanks.
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.
Sanger, G. A. 1972. Preliminary standing stock and biomass
estimates of seabirds on the subarctic Pacific region. Pages
589-611 _in_ A. Y. Yakenouti et al., eds. Biological oceanography
of the North Pacific. Idemitsy Shoten, Tokyo.
Serventy, D. L. 1958. Mutton-birding. Pages 233-234 _in_ A. H.
Chisholm, ed. The Australian Encyclopedia, Vol. 6. Angus and
Robertson, Sydney.
Serventy, D. L. 1969. Mutton-birding. Pages 53-60 _in_ K.
Taylor, ed. Bass Strait Australia's last frontier. Australian
Broadcasting Company, Sydney.
Serventy, D. L., U. Serventy, and J. Warham. 1971. Seabird
conservation problems in Australia. Pages 40-44 _in_ D. L.
Serventy, U. Serventy, and J. Warham. The handbook of Australian
birds. A. H. and A. W. Reed, Sydney.
Sowl, L. W., and J. C. Bartonek. 1974. Seabirds: Alaska's most
neglected resource. Trans. N. Am. Wildl. Nat. Resour. Conf.
39:117-126.
Stegner, W. 1968. The meaning of wilderness in American
civilization. Pages 192-197 _in_ R. Nash, ed. The American
environment: readings in the history of conservation.
Addison-Wesley Publishing Co., Reading, Massachusetts.
Tuck, L. M. 1960. The murres. Ottawa, Can. Wildl. Ser. 1. 260 pp.
Wildlife Management Institute. 1975. Current investments, projected
needs, and potential new sources of income for nongame fish and
wildlife programs in the United States. Wildlife Management
Institute, Washington, D.C. 55 pp.
Williamson, K. 1945. The economic importance of seafowl in the
Faeroes Islands. Ibis 87:249-269.
Wollman, N., chairman. 1962. The value of water in alternative
uses, with special application to water use in the San Juan and
Rio Grande basins of New Mexico. Univ. of New Mexico Press,
Albuquerque. 426 pp.
FOOTNOTES:
[51] Present address: National Audubon Society, 2 Marine Way, Juneau,
Alaska 99801.
Resource Development Along Coasts and on the Ocean Floor: Potential
Conflicts with Marine Bird Conservation
by
Donald E. McKnight
Alaska Department of Fish and Game
Subport Building
Juneau, Alaska 99801
and
C. Eugene Knoder
National Audubon Society
Lakewood, Colorado
Abstract
Although development of hard mineral
resources, expansion of the timber industry,
and resultant increases in human pressures
along the North Pacific and Arctic coasts
will ultimately adversely affect northern
marine bird populations, current and proposed
activities of the petroleum industry are the
most immediate threat to marine birds. The
Federal Government's recently announced plans
for oil and gas leasing on the Pacific outer
continental shelf eclipse the significance of
North Slope and Cook Inlet oil developments.
Within a few years, onshore storage facilities
and supertankers plying these waters will
undoubtedly result in widespread chronic
and localized catastrophic contamination of
northern marine ecosystems.
Coastal and offshore waters south of the
reaches of the seasonal ice pack are
tremendously productive, supporting a diverse
wealth of bird life throughout the year.
Because these ecosystems are relatively stable
and the impact of temporal oscillations on the
physical environment is not as great as in the
Arctic, birds in these areas are probably least
susceptible to man's influence on a long-term
basis.
Avifaunal associations of the Arctic are less
diverse and have shorter food chains than more
southerly ones; consequently they are more
susceptible to environmental perturbations.
Slow growth and maturation rates of arctic
species and resultant prolonged population
recovery periods further aggravate this
situation.
Available knowledge of northern seabirds
and their environmental requirements is in
inverse relation to the latitude at which they
are found and to the ecological stability
of the ecosystems involved. Arctic bird
associations and their fragile environments
are least understood, but are doubtless the
most vulnerable to the detrimental effects
of man-caused environmental degradation. The
paucity of knowledge about them limits the
possibility of predicting the consequences
of petrochemical exploitation and thereby
safeguarding against potential problems.
Existing technology and support system
capabilities of the oil industry are more
poorly defined for arctic areas, further
compounding this problem. Regardless
of information amassed in the future
and precautionary measures taken during
exploitation of arctic petroleum reserves,
the potential for disastrous and perhaps
irrecoverable losses to northern marine bird
species and populations is great. Losses of
major magnitude could appreciably alter the
productivity of northern marine ecosystems.
Although the coastal waters of the northwestern United States and
western Canada support a plenitude of marine life, including marine
birds, relatively little is known about these ecosystems. Sustained
interest in quantitative aspects of this area's marine bird populations
has developed only within the past few years. As Sowl and Bartonek
(1974) indicated, seabirds are the most visible component of a marine
ecosystem and, at the same time, they are the least understood.
Management information has been haphazardly gathered, and because
seabirds occur in incredibly large numbers in north Pacific and arctic
waters, it has been convenient to assume that, in the absence of
problems, systematized data gathering and analysis were unnecessary.
The sudden emergence in the late 1960's of Alaska and portions of
northwest Canada as potential major oil production areas has changed
this situation dramatically. Ongoing and planned petroleum development
in the North and the concurrent expansion of hard mineral extraction
and logging activities now threaten to adversely affect these marine
bird resources. Alaska's human population, which numbered only slightly
over 400,000 in 1975, will probably double within the present decade.
Doubtless, increased numbers of people, oriented toward mineral and
other resource exploitation rather than toward traditional wildland
values, will compound these problems. Pressures on State and local
governments for increased services necessitated by increasing
populations will require additional expenditures. In Alaska, at least,
these demands are being imposed before revenues from minerals become
available. This necessitates additional oil leases, timber sales, and
other means for obtaining immediate funding, thereby adding to the
acceleration and irreversibility of industrial expansion into the North.
This atmosphere of change has spawned major government-and
industry-supported programs to broaden knowledge of northern marine
ecosystems, including their avifauna. There has been a recent flurry
of publications on seabird populations and biology and a proliferation
of papers stressing the need to learn more about the biota of this
area. Nevertheless, environmental impact statements on proposed
developmental programs in the North still raise more questions than are
being answered. Attempts are being made to apply available information
on oil spills, human disturbance, and other aspects of environmental
degradation gathered from experiences in other areas to expected
problems in northern environments, but one must realize that much of
the information gained from experience elsewhere is not applicable to
these areas. It is realistic to assume that, until development-related
problems occur in the North, biologists cannot estimate the magnitude
or ecological dimensions of their effects. However, existing knowledge
of ecological "laws" and of the biology of some species provides the
base for limited predictive efforts.
It is the purpose of this paper to describe significant current and
proposed resource development along the coasts and the ocean floors,
to summarize existing knowledge of the ecology of marine birds in
these areas, and to identify potential conflicts with marine bird
conservation. We hope that identification of these problems will
provide impetus to data gathering and management programs necessary for
conservation of these valuable resources.
The Region and its Avifauna
The region discussed here encompasses nearly half of the United States
and Canadian coastlines, extending from Washington to the eastern
edge of the Northwest Territories. Alaska alone has two-thirds of the
United States' continental shelf (Bartonek et al. 1971). This region's
marine and estuarine waters are some of the most productive in the
world and support a diverse wealth of bird life throughout the year.
Sanger (1972), for example, estimated total summer standing stocks of
some 21 million birds in an area approximating the outer continental
shelf from the Bering Strait south along the coasts of the Aleutian
Islands and North America to central California. Sanger and King (this
volume), to whom more data were available, revised this estimate upward
to 45 million. Bartonek et al. (1974) provided estimates of year-round
standing stocks of 27 million birds in the Bering Sea alone.
North and east of the Bering Strait, population estimates of the
bird fauna are less complete. Swartz (1966) estimated, however, that
seabird populations of five colonies in the vicinity of Cape Thompson
in the Chukchi Sea exceeded a total of 420,000 breeding birds in 1960.
Information provided by Bartonek and Sealy (this volume) indicates that
large colony complexes at Cape Lisburne and Little Diomede Island each
number, in aggregate, over 1 million breeding birds, mainly alcids,
kittiwakes (_Rissa_ spp.), gulls (_Larus_ spp.), fulmars _(Fulmarus
glacialis)_, and cormorants (_Phalacrocorax_ spp.). Although the
Chukchi Sea coast north of Cape Lisburne has no rocks suitable for
cliff-nesting seabirds, large numbers of tundra-nesting species use
the inshore waters as a migratory pathway, and many nonbreeding cliff
nesters summer in these waters (J. M. Scott, comments by Pacific
Seabird Group on U.S. Department of the Interior Draft Environmental
Statement 74-90). According to Scott, sea ducks and gulls are the most
numerous birds in the Beaufort Sea. Observations by Thompson and Person
(1963) of an estimated 1 million eiders, mostly king eiders _(Somateria
spectabilis)_ and Pacific eiders _(S. mollissima)_, passing over
Point Barrow en route to molting areas, reflect the numbers involved.
Oldsquaws _(Clangula hyemalis)_ use coastal waters of the Beaufort Sea
for postbreeding wing molts; Bartels (1973) estimated their numbers at
nearly 400,000 in the fall and perhaps more during the molting period.
Shorebirds, jaegers (_Stercorarius_ spp.), gulls, and terns, most of
which use coastal waters at some time during the summer season, swell
bird numbers by several millions in this area (Arctic Institute of
North America 1974).
As indicated by Sanger (1972), the seabirds inhabiting coastal areas
south of Bering Strait are mainly members of the Procellariidae
in summer and Alcidae in winter. Sooty shearwaters _(Puffinus
griseus)_ are the prevalent summer species and ancient murrelets
_(Synthliboramphus antiquus)_ and marbled murrelets _(Brachyramphus
marmoratus)_ are the most abundant winter species. Sanger's central
subarctic domain (offshore waters including the Gulf of Alaska) had a
different species composition. During the summer, procellariids--mostly
slender-billed shearwaters _(Puffinus tenuirostris)_ and sooty
shearwaters--made up 94% of the biomass. Procellariids, including
fulmars, larids (largely glaucous-winged gulls, _Larus glaucescens_),
black-legged kittiwakes _(Rissa tridactyla)_, and large alcids,
including the tufted puffin _(Lunda cirrhata)_, made up 87% of the
winter biomass in this domain (Sanger 1972).
Although most of the arctic waters, including the Bering, Chukchi, and
Beaufort seas, are unavailable to birds during the winter because of
pack ice, they seasonally host an avifauna dominated by colony nesters,
such as common and thick-billed murres (_Uria aalge_ and _U. lomvia_),
and tundra nesters, such as oldsquaws and eiders. In far northern
waters, sea ducks (mainly eiders and oldsquaws), red phalaropes
_(Phalaropus fulicarius)_, and gulls are the predominant species.
Intertidal areas throughout the Alaska, British Columbia, and
Washington coasts support characteristic assemblages of shorebirds,
including the black oystercatcher _(Haematopus bachmani)_, rock
sandpiper _(Erolia ptilocnemis)_, wandering tattler _(Heteroscelus
incanum)_, surfbird _(Aphriza virgata)_, and black turnstone _(Arenaria
melanocephala)_ as reported by J. M. Scott (comments by Pacific Seabird
Group to U.S. Department of the Interior Draft Environmental Statement
74-90). Perhaps the greatest concentrations of shorebirds in this whole
region occur during spring and fall migrations in Prince William Sound.
The tremendous numbers of migrating birds using these tidal and marsh
areas are hard to imagine, but densities of up to 250,000 shorebirds
per 259 hectares (ha) on portions of the more than 51,820-ha tidal
flats of the Copper River Delta have been recorded (Isleib and Kessel
1973).
Although this region's avifauna is remarkable from the numerical
standpoint, it is important to remember also that some of its
species are limited in distribution to this area. According to
Bartonek et al. (1971), Alaska is the only known breeding area for
black turnstones, bristle-thighed curlews _(Numenius tahitiensis)_,
surfbirds, western sandpipers _(Ereunetes mauri)_, and Kittlitz's
murrelets _(Brachyramphus brevirostris)_. Several waterfowl species,
including the dusky Canada goose _(Branta canadensis occidentalis)_,
cackling Canada goose _(B. c. minima)_, Aleutian Canada goose _(B. c.
leucopareia)_, and Aleutian common teal _(Anas crecca nimia)_ nest only
in Alaska coastal areas (Bartonek et al. 1971). Izembek Lagoon on the
Alaska Peninsula annually hosts the entire population of black brant,
_Branta nigricans_ (Hansen and Nelson 1957), and many other waterfowl,
seabird, and shorebird species nest or live in this region in numbers
important to their worldwide welfare.
Current and Planned Resource Development
The immense nonrenewable resource wealth of Alaska and other arctic
regions has remained virtually unrecognized or unexploited until
recently because of the availability of these resources in more
accessible locations. As supplies have diminished or been exhausted
elsewhere and demands have increased, however, it has become
economically feasible or necessary to tap supplies in less-accessible
regions. For this reason, the petroleum industry has recently expanded
its exploratory efforts in the far North with well-known success.
Deposits of metallic ores, coal, and other raw materials to feed
industry have likewise been discovered and plans devised for their
extraction and sale. Pressed with decreased availability of commercial
timber elsewhere, the logging industry has similarly begun to broaden
its efforts into Alaska. Expansion of industrial activities into
the North is proceeding at a rapidly accelerating pace, and these
industries, their associated support industries, and expanded human
populations are having and will continue to have unprecedented impact
on these marine ecosystems, including their avifauna.
_Petroleum Development_
The existence of potentially marketable oil and gas deposits in Alaska
has been recognized since the early 1900's, but it was not until the
Swanson River, Alaska, oil field was discovered in 1957 and later
developed that the Arctic entered the modern era of oil development
(McKnight and Hiliker 1970). This field and offshore fields in the
Upper Cook Inlet basin have been producing oil for nearly a decade. The
discovery of petroleum reserves on Alaska's North Slope and Canada's
Mackenzie River Delta is common knowledge, and a pipeline has been
constructed to transport Alaska oil to a tanker facility at Valdez in
Prince William Sound. Alternative proposals to pipe North Slope natural
gas along the existing corridor to a facility in Prince William Sound
or to build a new pipeline to take this gas to existing fields, and a
planned pipeline on the Mackenzie River Delta and south through Canada,
are being considered. Construction of a gas liquefaction facility in
Prince William Sound and tanker traffic through the Sound and the Gulf
of Alaska are potential ramifications of an Alaska gas pipeline.
As McKnight and Hiliker (1970) and Bartonek et al. (1971) pointed
out, the greatest potential problem for marine bird populations from
North Slope oil will be associated with the operations of the Alyeska
Pipeline system's terminal at Valdez. Oil storage and ship-loading
facilities at this port and heavy tanker traffic through Prince William
Sound represent a pollution source that could result in significant
seabird and waterfowl mortalities. Certainly, development of gas
liquefaction facilities in the Sound, with inherent increases in human
populations and tanker traffic, would compound this potential problem.
Although future impacts from existing petrochemical developments
are cause for concern, the Federal Government's recently announced
plans for oil and gas leasing on the Pacific outer continental shelf
(Fig. I) eclipse the significance of North Slope and Cook Inlet oil
developments. It now appears the Gulf of Alaska is the most favorable
area of the outer continental shelf for oil and gas production
(Council on Environmental Quality 1974). This area, covering more
than 10.3 million ha, has already been subjected to extensive seismic
investigations, and estimates of its undiscovered, economically
recoverable crude oil and natural gas resources range from 3 to 25
billion barrels and 15 to 30 trillion cubic feet, respectively (Council
on Environmental Quality 1974).
[Illustration: Fig. 1. North Pacific, showing portions of the outer
continental shelf being considered for gas and oil leasing by the
Federal Government (vertical hatching) and areas leased or proposed for
leasing by the State of Alaska (cross hatching).]
Kinney et al. (1970) reported that in Cook Inlet, Alaska, an estimated
0.3% of the oil produced and handled in offshore platform wells is
spilled. Several routine offshore operations result in discharges of
oil and other materials into water, and, unlike accidental spills,
the probability of their occurrence is 100% (Council on Environmental
Quality 1974). During drilling operations, cleaned drilling mud and
drill cuttings are discharged overboard. Drilling mud may consist of
such substances as bentonite clay, caustic soda, organic polymer,
proprietary defoamer, and ferrochrome lignosulfate. Waters from
geological formations are often produced and discharged into the
sea while the wells are in production. These waters may be fresh or
saline, and often contain small amounts of oil. All of these pollutants
increase the adverse effects of offshore oil production, and when
potential spills are also considered, the ultimate impact on the marine
ecosystem may be substantial.
The State of Alaska has already leased offshore sites in Kachemak Bay,
and present considerations for future leases in the lower Cook Inlet
and Beaufort Sea further reflect the widespread and massive nature of
petrochemical developments in the Arctic planned for the next 2 decades
(Fig. 1). Proved crude oil reserves are less than 1 billion barrels and
natural gas reserves are less than 2 trillion cubic feet in Cook Inlet,
but it appears that undiscovered recoverable oil and gas resources
may be much greater (Council on Environmental Quality 1974). There
are also indications that known onshore oil reserves along Alaska's
northwest coast will soon be opened for development by the Arctic
Slope Regional Corporation, landowners in the area as a result of the
Native Land Claims Act of 1971. This group is at least considering the
transportation of these petroleum products to market in tankers, from
an open-water port in the Chukchi Sea--thereby adding to the tanker
traffic in northern waters.
_Hard Mineral Resource Development_
As indicated by Bartonek et al. (1971), there has been renewed interest
in opening up Alaska's hard mineral resources to economic development
as new transportation routes and modes have been developed. Plans
are being completed to develop the Bering River coal field, with the
eventual goal of exporting coking coal to Japan. Although mining
operations might ultimately affect freshwater environments to the
detriment of several waterfowl species, including the trumpeter swan
_(Olor buccinator)_, the chief cause for concern will be additional
freighter traffic through Prince William Sound. Similar plans to
develop Klukwan and Snettisham iron deposits in southeastern Alaska for
the use of Japanese industry (Bartonek et al. 1971) may result in the
imposition of further traffic in Alaska shipping lanes.
Plans are under way to strip-mine coal deposits in the Beluga field
near the west side of Cook Inlet and transport a coal slurry via
pipeline to a thermal electric generation plant opposite Anchorage on
the Inlet. Impact on tidal areas may be minor, but thermal pollution of
the waters is a possibility.
Development plans for tin and tungsten deposits in the Lost River area
of Alaska's Seward Peninsula are under way after several years of
faltering starts and stops. These activities and possible extraction of
gold lying offshore from Nome may ultimately have some effect on these
coastal areas. Methods for recovering gold, regardless of the type,
would disrupt marine and estuarine environments used by marine birds
(Bartonek et al. 1971), and transportation of ores would also increase
freighter traffic in the Bering Sea.
_Timber Resource Development_
Although the timber industry has long been established along the coast
from Washington north through southeastern Alaska, timber harvests
are rapidly expanding on U.S. Forest Service lands in Alaska. The
impact of this industry is principally on terrestrial ecosystems, but
certainly log rafting in estuarine areas, disposal of wastes from
pulp mills, and freighter traffic transporting wood pulp or logs to
Japan and west coast markets contribute to the chronic degradation
of marine bird environments. Recent meager studies on the Vancouver
Canada goose _(Branta canadensis fulva)_ in southeastern Alaska have
pointed out the importance to this species of coastal timber stands for
nesting and estuarine environments for brood rearing and wintering.
This essentially nonmigratory goose (Hansen 1962) may be particularly
vulnerable to logging activities in these areas. Similarly, recent
evidence indicates that marbled murrelets may nest in large conifer
trees adjacent to the coast, from northwestern California to
northern southeastern Alaska (Harris 1971; Savile 1972). If this is
true, logging may eventually greatly restrict the breeding of this
numerically important inhabitant of northern coastal waters.
Assessment of Resource Development and Potential Conflicts with Marine
Bird Conservation
Although extraction of hard mineral resources, expansion of the timber
industry, and resultant increases in human pressures along North
Pacific and Arctic coasts will ultimately affect northern marine bird
populations, current and proposed activities of the petroleum industry
pose the most immediate threat to marine birds. Chronic degradation of
estuarine and marine coastal waters by logging wastes, pulp mill and
sewage effluents, and bilge oils is an insidious process, the impacts
of which will be difficult, at best, to quantify. Results of a major
oil spill or even low-level contamination of marine ecosystems with oil
will be more apparent, however. For this reason, and the fact that the
industry is expanding rapidly into the North, most of this discussion
will be directed at the impacts of oil development on northern marine
birds.
Potential sources of adverse environmental degradation affecting
these birds resulting from oil and gas exploration, development,
and production include: (1) oil discharges into marine waters, both
chronic and catastrophic, (2) gravel excavation and dumping in coastal
areas, (3) seismic activities, (4) discharge of drilling mud and drill
cuttings into marine waters, including toxic heavy metal constituents
of drilling mud, (5) disturbance resulting from petrochemical
activities, and (6) increased human populations resulting in
interference with critical life processes and increased hunting of game
species. Each source of environmental change will vary by latitudinal
and seasonal factors in their effects upon the birds. We consider
herein only coastal and ocean floor developments and their anticipated
generalized impacts on populations.
Although this is a discussion of "northern" marine birds, it is
important to remember that we are considering a diverse avifauna
existing in an environmental gradient from temperate to polar regions.
In general, the more southerly portions of this marine environment
are characterized by a greater diversity of species, more complex
food chains, and a resultant greater stability (Dunbar 1968). Arctic
marine ecosystems, on the other hand, are characterized by numerical
dominance by a few species, relatively simple food chains, and an
inherent instability or fragility (Dunbar 1968). According to Dunbar,
arctic systems are regulated primarily by temporal oscillations in
the physical environment, whereas biological interactions (e.g.,
competition, predation) are considered more significant in the
maintenance of temperate and tropical ecosystems.
Because of their relative instability, arctic ecosystems are more
susceptible to alteration by extreme environmental perturbation,
either natural or man-imposed (Burns and Morrow 1973). Slow growth and
maturation rates of the avian constituents of these ecosystems and
resultant long recovery periods (Ashmole 1971) further aggravate this
situation.
Regardless of their seasonal availability, these arctic waters
constitute some of the most productive areas for seabirds in the
western hemisphere (Bartonek et al. 1974). Upwelling, nutrient-rich
waters, combined with intense and prolonged incident radiation, result
in lush phytoplankton "blooms" that form the foundation of relatively
simple but numerically strong plant and animal communities (Ashmole
1971). A relatively small number of avian species have evolved to take
advantage of this seasonally available food supply, and the ability
to migrate to lower latitudes in winter is a characteristic of most
arctic-nesting species. Because summers are short in arctic regions,
early arrival and a synchronous breeding schedule are necessary
to enable the young to leave the breeding grounds before severe
weather conditions prevail (Ashmole 1971). Arrival of these birds
generally coincides closely with the earliest availability of nesting
habitat and food (Williamson et al. 1966). Migration, molting, and
reproduction place tremendous stresses on these birds, and as a result,
arctic-nesting species tend to reproduce less often and at older ages
than do those of more temperate regions (Ashmole 1971).
In spite of these adaptations, arctic bird species tread a thin line
between extinction and survival, and natural disasters take a heavy
toll. Bailey and Davenport (1972) reported a massive mortality in a
pelagic population of common murres in Bristol Bay, Alaska, during
April 1970. They felt that this disaster, resulting in the death of
probably 100,000 or more birds, most likely resulted from starvation
precipitated by severe weather. Barry (1968) reported a similar loss to
starvation of about 100,000 eiders along the Beaufort Sea coast during
the extremely cold spring of 1964. Observers along Alaska's Beaufort
Sea reported finding eiders and oldsquaws dead and dying from the
effects of cold weather in 1970 (Bartonek et al. 1971). It is readily
apparent that the tenuous existence into which these birds have evolved
leaves them particularly vulnerable to the man-induced stress of
developments during the arctic summer.
_Direct Effects of Oil Pollution_
The most obvious, and perhaps the most disastrous consequence of
petrochemical development on northern marine bird populations is that
of a major oil spill or a well blowout into marine waters. Although
temperate and tropical waters are apparently able to assimilate
oil spills and chronic pollution from petroleum and its products
(Nelson-Smith 1972), this has not been demonstrated to be true for
arctic waters. In fact, studies in the Beaufort Sea have shown that
the bacteria that degrade oil do not use hydrocarbons at the ambient
temperatures of the Arctic (Glaeser and Vance 1971). Therefore, a large
oil spill in the Arctic could persist for many years. As demonstrated
by Campbell and Martin (1973), the diffusion and transport mechanisms
generated by the pack-ice dynamics of the Beaufort Sea and the slow
rate of oil biodegradation under arctic conditions would combine to
diffuse an oil spill over the sea and eventually deposit oil on the
ice surface. This, in turn, would lower the natural albedo over a
large area and melt the ice in the area of the spill. This pack ice
supports an under-ice community which is an important food source for
phalaropes, jaegers, gulls, terns, and other seabirds (Watson and
Divoky 1972).
As indicated by Nelson-Smith (1972) many investigators have stated that
a spot of oil "no bigger than a dollar" on the breast of a bird is
enough to bring about death by exposure, at least in the colder seas.
It is easy to see the relative vulnerability of already stressed birds
in arctic areas to a spill, and because of the concentration of these
birds in available open-water areas, possibilities for catastrophic
mortalities are evident.
Such disasters already have occurred in north Pacific waters. Dickason
(1970) reported an incident in which diesel oil reaching the Alaska
coast, probably from the sinking of two Japanese freighters some
distance offshore, affected an estimated 90,000 murres. J. G. King, Jr.
(cited in Bartonek et al. 1971) estimated that at least 100,000 birds,
mostly alcids and waterfowl, died in the vicinity of Kodiak Island
during winter 1970 as a result of oil pollution (probably ballast
dumped by tankers entering Cook Inlet). It must not be forgotten that
chronic pollution in similar areas where oil development and transport
activities are taking place probably kills more birds every year than
die after a single catastrophic spill. Total annual losses due to oil
in the North Sea and North Atlantic, excluding disasters, amount to
150,000 to 450,000 seabirds (Nelson-Smith 1972).
That oil pollution, both chronic and catastrophic, can dramatically
affect populations of marine birds has already been demonstrated
elsewhere. Uspenskii (1964) reported that more than 30,000 wintering
oldsquaws perished from oil pollution near Botland Island in the Baltic
and that in later years this species had almost disappeared from
Swedish Lapland. Jackass penguins _(Spheniscus demersus)_, found only
in South Africa, have suffered losses from pollution caused by oil
traffic around the Cape of Good Hope (Stander and Venter 1968). Their
total population was estimated at 100,000 in 1960, and in two separate
but not isolated incidents 1 to 2% of this number were known to have
been killed by oil. Unknown but considerable numbers were uncounted
or were lost at sea. Colony nesters, including puffins _(Fratercula
arctica)_, razorbills _(Alca torda)_, and murres in the southerly
portions of the North Sea are declining rapidly (Nelson-Smith 1972).
Puffins, which numbered 100,000 on Annet in the Scilly Isles in 1907,
were reduced to 100 birds by 1967; by then, colonies farther east
on the Great Britain coast were already extinct. Pollution from the
_Torrey Canyon_ disaster alone killed five-sixths of the puffins in
the main French colony on the Sept Isles in Brittany and reduced the
razorbills to a mere 50 birds, one-ninth of previous numbers (Bourne
1970).
There is every reason to believe that similar reductions in numbers
could occur along the tanker route from Valdez to Puget Sound, with
localized extirpation of colonies. Even more disastrous, however, would
be an inopportune well blowout or other major spill in arctic waters.
Massed concentrations of birds, already stressed by severe weather and
food shortages, would be extremely vulnerable to this type of situation.
As pointed out by Nelson-Smith (1972), peculiarities of bird behavior
determine, to some extent, the vulnerability of a species to oil
spills. Auks, murrelets, and puffins (all Alcidae), loons (_Gavia_
spp.), grebes (_Podiceps_ spp.), and diving ducks may be most
susceptible to oiling. Auks and loons, because they float low in the
water, may more readily become completely covered by oil. Diving
species that become flightless during their molt, such as alcids and
waterfowl, or which do not fly because of social bonds between adults
and flightless young (common murre) and spend most of their lives on
the water, would be particularly vulnerable (J. M. Scott, comments
by Pacific Seabird Group on U.S. Department of the Interior Draft
Environmental Statement 74-90). All divers can easily surface into
oil, and their reaction is to dive again, which in a large spill could
result in surfacing into more oil. Phalaropes (_Phalaropus_ spp.),
which flock to feed in eddies which concentrate drift, may similarly be
vulnerable to adverse effects of oil that would also concentrate in
these areas. On the other hand, gulls swimming along the surface are
likely to take wing before becoming seriously contaminated.
Nelson-Smith (1972) reported that gannets _(Morus bassana)_, which
collected oiled sea-weed for building nest mounds, contaminated
themselves and their eggs. Behavioral problems associated with oil
spills can be more subtle, however, and Darling's (1938) conclusions
that the display of adjacent males contributes to stimulation of the
female during courtship in seabirds breeding in massed colonies, is a
good example. If Darling was correct, this behavioral characteristic
could further impede the recovery of a population of auks, for example,
from mortalities resulting from catastrophic losses to spills.
* * * * *
On the basis of this information it is possible to predict that alcids,
which make up the bulk of the birds inhabiting the coastal areas during
winter (Sanger 1972), would be very susceptible to oil spills from
future tanker traffic in these waters. The potential exists, therefore,
for a tremendous impact (from a single inopportune oil spill) upon
these species and upon the entire ecosystem. Sea ducks too, because of
their diving behavior, propensity for flocking, and flightless molt
period, would be very vulnerable to oil spills. Wintering flocks of
oldsquaws and several species of scoters along the coasts of Alaska,
British Columbia, and Washington can be expected to dwindle as North
Slope oil begins to be transported to Puget Sound ports.
It is recognized now that seabirds transfer and recycle nutrients and
energy between trophic levels and between regions of an ocean (Sowl and
Bartonek 1974). Although the significance of this role in the marine
ecosystem can only be surmised at present, conservative estimates by
Sanger (1972) indicated that birds consume from 0.6 to 1.2 million
tons of food and return from 0.12 to 0.24 million tons of feces into
the subarctic Pacific region annually. G. A. Sanger's (personal
communication) revised estimates of these bird populations indicated
that his 1972 estimates should be doubled. Regardless, it appears that
the disastrous effects of such a spill would extend beyond the bird
populations involved.
_Indirect Effects of Oil Pollution and Petrochemical Developments_
By no means would direct losses attributable to contamination by oil be
the only threat to marine bird populations as a result of petrochemical
expansions into these waters. Some water birds that become contaminated
with nonlethal doses of petroleum during the breeding season are
not likely to breed (J. M. Scott, comments by Pacific Seabird Group
on U.S. Department of the Interior Draft Environmental Statement
74-90). Viability of embryos is greatly reduced when the eggshell
becomes smeared with oil from the contaminated plumage of the female
(Hartung 1965). Degradation of habitat, particularly to nesting areas
and food supplies, will certainly occur, and its most pronounced
effects will be felt in the Arctic. Gravel removal for construction of
offshore drilling pads, causeways, and onshore production facilities
would displace nesting birds and, combined with subsequent discharge
of drill cuttings, perhaps have an adverse impact on bottom food
organisms. Nesting habitat loss through destruction or the inability
of birds to accept disturbance could be substantial, particularly
along the Beaufort Sea coasts of Alaska and Canada, where offshore
barrier islands and tundra-covered islands provide protection from
mammalian predators for nesting by Pacific eiders, Sabine's gulls
_(Xemia sabini)_, Arctic terns _(Sterna paradisaea)_, black guillemots
_(Cepphus grylle)_, and other species (Arctic Institute of North
America 1974). Flaxman Island near the mouth of the Canning River is a
tundra island supporting a nesting population of whistling swans _(Olor
columbianus)_, and the only nesting colony of the Alaska snow goose
_(Chen caerulescens)_ is on Howe Island in the Sagavanirktok River
Delta (Arctic Institute of North America 1974).
* * * * *
Although there would probably be little actual nesting habitat loss for
cliff-nesting species, human disturbance to colonies during the nesting
period, particularly from helicopter and fixed-wing aircraft flybys,
could have considerable impact (Sowl and Bartonek 1974). The "living
waterfall" effect of thousands of seabirds pouring off a rookery is
truly spectacular, but each such occurrence during incubation and
brooding periods causes a rain of eggs or young to fall from the cliffs
(Sowl and Bartonek 1974). Temporarily abandoned chicks and eggs are
susceptible to predation by gulls or jaegers.
Even for species nesting on level ground, aircraft overflights close
to breeding colonies may cause major losses to young and eggs. Sladen
and LeResche (1970) reported that flights by an LH-34 helicopter (at
305 m altitude) over an Adelie penguin _(Pygoscelis adeliae)_ colony
caused some egg loss. Landing this aircraft 183 m from the colony
caused 50 to 80% of the birds to flee territories, resulting in egg
and chick loss. Disturbance caused by visitors walking through or near
nesting areas of the South African gannet _(Sula capensis)_ on Bird
Island, Lamberts Bay, South Africa, caused desertion of nesting sites
(Jarvis and Cram 1971). Studies of disturbance on breeding black brant,
Pacific eiders, glaucous gulls _(Larus hyperboreus)_, and arctic terns
at Nunaluk Spit and Phillips Bay, Yukon, in July 1972 indicated that
human presence was the most critical form of disturbance affecting
incubating behavior of these species (LGL Limited 1972_a_). Disturbance
by aircraft--especially helicopters--affected the normal incubating
behavior of all species except Pacific eiders. Nesting success of black
brant and arctic terns was reduced by this disturbance.
Disturbance can adversely affect molting birds. The process of molting
places heavy energy demands on birds, and particularly on waterfowl
whose molt results in a flightless period; few areas provide adequate
protection from predators necessary during this period. Prime molting
areas are scarce along the arctic coast, yet are vital to the welfare
of thousands of sea ducks and seabirds. Studies conducted by LGL
Limited (1972_b_) indicated that aircraft traffic over sea duck molting
areas altered normal behavior, and therefore had a detrimental effect.
Recommendations resulting from these studies were that air traffic be
suspended over these areas during the molting season.
For some arctic-nesting waterfowl, premigration staging activity,
during which fat reserves to sustain southward migration are stored, is
a very important component of the annual cycle (Delacour 1964). Snow
geese, breeding mainly in arctic Canada, concentrate in large numbers
on staging grounds along the Beaufort Sea coast of eastern Alaska and
the Yukon. Because gas compressor stations would be required along the
proposed arctic gas pipeline route, experimental studies were conducted
in September 1972 to determine the effect of disturbance from sounds
generated by compressors (LGL Limited 1972_c_). These studies indicated
that compressor noise was disruptive to staging geese.
Indirect effects on marine bird resources resulting from development
activities may ultimately prove to be more detrimental than the
aforementioned direct factors. It is conceivable that the impact of
these industries, mainly on the benthic and demersal fauna of the
coastal areas, could greatly lower the carrying capacity of this
habitat for marine birds (Bartonek et al. 1974). Because of the
simplified and short arctic food chains and the lack of alternative
food sources in these areas, arctic ecosystems would be particularly
vulnerable to this type of problem (Burns and Morrow 1973).
Ecological or toxic influences on several food species could result
in substantial declines in bird populations. In the Arctic, where
temperatures are low, and bacterial and other decompositional
activities are consequently slow, spilled oil would persist for many
years, with concomitant deleterious effects on the marine organisms of
the area (Burns and Morrow 1973). Reduced recruitment of young would no
longer balance inevitable or density-independent population mortality
(Ashmole 1971). Although indications are that arctic species are the
most vulnerable to this type of impact, the lack of knowledge of the
feeding niches of most seabirds discourages further evaluation of this
potential problem. It is obvious, however, that ecology of arctic birds
is least understood, and these species are the most vulnerable to the
detrimental effects of man-caused environmental degradation.
Conclusions
Predictability of the impact of resource development on marine birds in
northern waters is limited by our relative ignorance of these birds
and their ecology. Just as there exists a latitudinal gradient in the
ecological stability of the ecosystems involved, available knowledge of
these ecosystems is in inverse relationship to the latitude at which
they occur. Arctic bird associations and their fragile environments
are least understood but are doubtless the most vulnerable to the
detrimental effects of man-caused environmental degradation. Existing
technology and support system capabilities of the oil industry are
poorly defined for Arctic areas, further compounding this problem
(Arctic Institute of North America 1974).
Although activities associated with the extraction of hard minerals
and the timber industry will ultimately affect northern seabirds,
petrochemical developments pose the most immediate threat to this
resource. Exploration and development of many coastal and offshore
sedimentary basins with a potential for oil or gas production are
proceeding rapidly. Within a few years, oil storage and loading
facilities at Valdez, Alaska, and supertankers plying northern waters
will probably result in widespread chronic and localized catastrophic
contamination of northern marine environments. Experience in other
areas has demonstrated that oil spills are a considerable potential
threat to these bird populations, directly through widespread mortality
and indirectly through effects on the environment. This threat is of
such magnitude that entire populations or species could be lost to a
single spill if it occurred at the wrong place at the wrong time of
year. Because many of these species require 3 to 4 years for maturation
and may rear only one or two young per year, recovery time for their
populations is great (Ashmole 1971). For these and other reasons, the
Council on Environmental Quality (1974) concluded that the Gulf of
Alaska appeared more vulnerable to major environmental damage from
outer continental shelf oil and gas development than sites off the
Atlantic coast.
As Bartonek et al. (1971) pointed out, it would be a national
tragedy if the great nongame bird populations along Alaska's coast
were decimated during the "Environmental Decade" without even being
properly described. Regardless of information amassed in the future and
precautionary measures taken during exploitation of arctic petroleum
reserves, the potential for disastrous and perhaps irrecoverable losses
to northern marine bird species and populations is great. Losses of
major magnitude could appreciably alter the productivity of northern
marine ecosystems, to the detriment of other renewable resources.
Knowledge of northern marine birds, their environments, and their
ecology must be greatly expanded if the consequences of petrochemical
exploitation are to be predicted and safeguards established against
potential problems. To the extent possible, oil exploration and
development activities should be limited to temperate, more stable,
marine ecosystems, at least until more northerly areas are better
understood. Similarly, these activities must be conducted in such
places and at such times that impact on the environment will be
minimized. State and federal governments and the petroleum industry are
ultimately answerable for this responsibility.
The Nation must be aware of the potential costs of energy independence
set forth as a goal of proposed oil and gas leasing of Alaska's outer
continental shelf. We must ask ourselves if we are willing to risk
extermination of species to reach this goal, or if we can afford the
luxury of reducing the biological productivity of these waters.
References
Arctic Institute of North America. 1974. The Alaskan arctic
coast--a background study of available knowledge. 551 pp.
Ashmole, N. P. 1971. Seabird ecology and the marine environment.
Pages 223-286 _in_ D. S. Farner and J. R. King, eds. Avian
biology. Vol. I. Academic Press, New York.
Bailey, E. P., and G. H. Davenport. 1972. Die-off of common murres
on the Alaska Peninsula and Unimak Island. Condor 74(2):215-219.
Barry, T. W. 1968. Observations on natural mortality and native
use of eider ducks along the Beaufort Sea coast. Can. Field-Nat.
82(2):140-144.
Bartels, F. B. 1973. Bird survey techniques on Alaska's north
coast. M.S. Thesis. Iowa State Univ., Ames. 47 pp.
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.
Bartonek, J. C., R. Elsner, and F. H. Fay. 1974. Mammals and birds.
Pages 23-28 _in_ E. J. Kelley and D. W. Hood, eds. Probes: a
prospectus on processes and resources of the Bering Sea shelf,
1975-1985. Univ. Alaska, Inst. Mar. Sci. Publ. Inf. Bull. 74-1.
Bourne, W. R. P. 1970. Special review after the "Torrey Canyon"
disaster. Ibis 112:120-125.
Burns, J. J., and J. E. Morrow. 1973. The Alaskan Arctic marine
mammals and fisheries. Arctic oil and gas problems and
possibilities, 5th International Congress. 24 pp.
Campbell, W. J., and S. Martin. 1973. Oil and ice in the Arctic
Ocean: possible large-scale interactions. Science 181:56-58.
Council on Environmental Quality. 1974. OCS oil and gas--an
environmental assessment. Vol. I. Washington, D.C. 214 pp.
Darling, F. F. 1938. Bird flocks and the breeding cycle; a
contribution to the study of avian sociability. Cambridge Univ.
Press, N.Y.
Delacour, J. 1964. The waterfowl of the world. Vol. IV. Country
Life Ltd., London. 364 pp.
Dickason, O. E. 1970. Center for short-lived phenomena event
report. Smithsonian Institution, Cambridge, Massachusetts,
36(1970):926.
Dunbar, M. J. 1968. Ecological development in polar regions. A
study in evolution. Prentice-Hall, Inc., Englewood Cliffs, N.J.
119 pp.
Glaeser, J. L., and G. P. Vance. 1971. A study of the behavior of
oil spills in the Arctic. U.S. Coast Guard, Office of Research
and Development, Washington, D.C. 60 pp.
Hansen, H. A. 1962. Canada geese of coastal Alaska. Trans. N. Am.
Wildl. Nat. Resour. Conf. 27:301-320.
Hansen, H. A., and U. C. Nelson. 1957. Brant of the Bering
Sea--migration and mortality. Trans. N. Am. Wildl. Nat. Resour.
Conf. 22:237-256.
Harris, R. D. 1971. Further evidence of tree nesting in the marbled
murrelet. Can. Field-Nat. 85(1):67-68.
Hartung, R. 1965. Some effects of oiling on reproduction of ducks.
J. Wildl. Manage. 29(4):872-874.
Isleib, M. E., and B. Kessel. 1973. Birds of the north gulf
coast--Prince William Sound region, Alaska. Biol. Pap. Univ.
Alaska 14. 149 pp.
Jarvis, M. J. F., and D. L. Cram. 1971. Bird Island, Lamberts
Bay, South Africa: an attempt at conservation. Biol. Conserv.
3(4):269-272.
Kinney, P. J., D. K. Button, D. M. Schell, B. R. Robertson, and J.
Groves. 1970. Quantitative assessment of oil pollution problems
in Alaska's Cook Inlet. Univ. Alaska Inst. Mar. Sci. Rep.
R-69-16. 43 pp.
LGL Limited. 1972_a_. Disturbance studies of breeding black brant,
common eiders, glaucous gulls and Arctic terns at Nunaluk Spit
and Phillips Bay, Yukon Territory. Report prepared for Northern
Engineering Service, Ltd. 50 pp.
LGL Limited. 1972_b_. Aircraft disturbance to molting sea ducks,
Herschel Island, Yukon Territory. Report prepared for Northern
Engineering Service, Ltd. 31 pp.
LGL Limited. 1972_c_. Gas compressor noise simulator disturbance to
snow geese, Kamakuk Beach, Yukon Territory. Report prepared for
Northern Engineering Service, Ltd.
McKnight, D. E., and B. L. Hiliker. 1970. The impact of oil
development on waterfowl populations in Alaska. Proc. Western
Assoc. State Game Fish Comm. 50:286-297.
Nelson-Smith, A. 1972. Oil pollution and marine ecology. Paul Elek,
Ltd., London. 260 pp.
Sanger, G. A. 1972. Preliminary standing stock and biomass
estimates of seabirds on the subarctic Pacific region. Pages
589-611 _in_ A. Y. Takenouti et al., eds. Biological oceanography
of the North Pacific. Idemitsu Shoten, Tokyo.
Savile, D. B. O. 1972. Evidence of tree nesting by the marbled
murrelet in the Queen Charlotte Islands. Can. Field-Nat.
86(4):389-390.
Sladen, W. J. L., and R. E. LeResche. 1970. New and developing
techniques in antarctic ornithology. Pages 585-616 _in_ M. W.
Holdgate, ed. Antarctic Ecology. Vol. I. Academic Press.
Sowl, L. W., and J. C. Bartonek. 1974. Seabirds--Alaska's most
neglected resource. Trans. N. Am. Wildl. Nat. Resour. Conf.
39:117-126.
Stander, G. H., and J. A. V. Venter. 1968. Oil pollution in South
Africa. Pages 251-259 _in_ Proceedings of the International
Conference on Oil Pollution of the Sea.
Swartz, L. G. 1966. Sea-cliff birds. Pages 611-678 _in_ N. J.
Wilimovsky and J. N. Wolfe, eds. Environment of the Cape Thompson
region, Alaska. U.S.A.E.C., Div. Tech. Inf., Oak Ridge, Tennessee.
Thompson, D. Q., and R. A. Person. 1963. The eider pass at Point
Barrow, Alaska. J. Wildl. Manage. 27(3):348-356.
Uspenskii, S. M. 1964. Present day problems of nature conservation
in the Arctic. Problems of the North 7:171-178.
Watson, G. E., and G. J. Divoky. 1972. Pelagic bird and mammal
observations in the eastern Chukchi Sea, early fall 1970. Pages
111-172 _in_ C. I. Merton et al., eds. An ecological survey in
the eastern Chukchi Sea. U.S. Coast Guard Oceanogr. Rep. 50.
Williamson, F. S. L., M. C. Thompson, and J. Q. Hines. 1966. Pages
437-480 _in_ N. J. Wilimovsky and J. N. Wolfe, eds. Environment
of the Cape Thompson region, Alaska. U.S.A.E.C., Div. Tech. Inf.,
Oak Ridge, Tennessee.
Mortality to Marine Birds Through Commercial Fishing
by
Warren B. King
International Council for Bird Preservation
Smithsonian Institution, Washington, D.C.
R. G. B. Brown
Canadian Wildlife Service
Dartmouth, Nova Scotia, Canada
and
Gerald A. Sanger[52]
U.S. National Marine Fisheries Service
Seattle, Washington
Abstract
Commercial fishing has been responsible for
incidental mortality of seabirds for centuries,
but with the advent of offshore salmon gill-net
fishing in the North Pacific in 1952 and in
the North Atlantic in 1965, the magnitude of
this kill has increased, and there is strong
indication that populations of some seabirds
are being adversely affected. Murres (_Uria_
spp.) are most frequently killed, although
several other species are caught in lesser
numbers. The seabird resources of several
nations are involved in this mortality.
Longline fishing and inshore gill-net fishing
for salmon and cod also are responsible for
mortality of seabirds, although usually not in
significant numbers.
That the activities of commercial fishermen have caused mortality of
marine birds surprises no one nowadays. Traditions of exploitation of
marine birds by fishermen date from previous centuries, and fishing
has contributed to the extinction of some species. For example, great
auks _(Pinguinus impennis)_ and other birds were used as food by
fishermen fishing for Atlantic cod _(Gadus morhua)_ on the Grand Banks
of Newfoundland since the beginning of that fishery in the early 16th
century (Collins 1884; Lucas 1890). The last great auk died in 1844,
but smaller species, such as storm-petrels (Hydrobatidae), greater
shearwaters _(Puffinus gravis)_, and black-legged kittiwakes _(Rissa
tridactyla)_, were used for food until rather recently (Templeman
1945). This practice has now lapsed, however.
Inshore Fisheries
Until the advent of the offshore salmon gill-net fisheries in the North
Pacific in 1952 and the North Atlantic in 1965, most seabird mortality
in these areas was the result of local fishing close to shore. Several
records of such bird mortality have been published. For example,
8,000-10,000 seabirds--presumably mostly alcids--were reported caught
annually off Hammerfest in northern Norway (Holgersen 1961). E. Brun
(personal communication) reported that the longline fishery off the
coast of Norway is having serious consequences on Norwegian populations
of murres.
Numbers of alcids are caught in nets set for Atlantic salmon _(Salmo
salar)_ around the coasts of Ireland and Scotland (Biddy 1971). A
similar situation exists along the west Greenland coast, although it
is overshadowed there by the direct exploitation of huge numbers of
alcids by hunting. Nonetheless, in 1967 for example, 15,000 alcids
were recovered from fish nets in southwestern Greenland, where they
were sold as food (Evans and Waterston 1976). The annual salmon catch
of the west Greenland inshore fishery has fluctuated between 60 and
1,500 metric tons and has averaged about 1,000 tons. There are no data
comparing the relative catch of birds and fish in this fishery.
Atlantic cod follow the spawning capelin _(Mallotus villosus)_ inshore
along the east coast of Newfoundland in late June and early July. They
are traditionally fished with traps and handlines along this coast,
but there has been a recent trend toward using drift nets set on the
bottom. Since alcids feed extensively on capelin at this time, many are
caught in the cod nets set in areas close to the large colonies off
Witless Bay (D. N. Nettleship, personal communication). Additionally,
gill nets are set at the surface for salmon in the same area. Common
murres _(Uria aalge)_ are most affected, but Atlantic puffins
_(Fratercula arctica)_ are also taken.
There are as yet no estimates of the total alcid mortality from this
fishery, although the annual catch of birds is believed to be smaller
during the present than during the last decade because the fishing
effort is reduced, and fishermen in the area now avoid setting nets
near alcid concentrations because of the annoyance of having to remove
the birds from their nets. The Witless Bay colonies contain over 77,000
pairs of common murres, or 11% of the total eastern North American
population, and over 235,000 pairs of Atlantic puffins, or 71% of the
North American population outside of Greenland (Brown et al. 1975). The
potential danger is obvious.
There are few data on mortality of seabirds from inshore commercial
fisheries in the North Pacific. Some mortality of alcids has been shown
to take place in Cook Inlet, Alaska, from beach-netting for Pacific
salmon (_Oncorhynchus_ spp.) adjacent to seabird rookeries and from
drift-netting in the inlet (D. A. Snarski, personal communication), but
this mortality has not been quantified.
Bilateral agreements between the United States and Japan, the U.S.S.R.
and the Republic of Korea, concerning the use of inshore waters
adjacent to some of the Aleutian Islands, Kodiak, Nunivak, St. Matthew,
St. George, Kayak, and Forrester Islands permit trawling, longlining,
and loading fish and fuel in some of these areas and at certain
periods. Although these activities may affect the seabirds of these
areas, the extent of the effects are not known (U.S. Department of the
Interior, Alaska Planning Group 1974). Murie (1959) indicated, however,
that the disappearance of the ancient murrelet _(Synthliboramphus
antiquus)_ from Sanak Island, Gulf of Alaska, was probably due as much
to fisheries as to the blue fox industry. It has been suggested that
the Japanese murrelet _(Synthliboramphus wumizusumi)_ may have declined
as the result of fishing activities near breeding sites off the coast
of Japan (Bourne 1971).
Atlantic Offshore Gill-net Fishery
In 1965, Denmark began an offshore gill-net fishery for Atlantic salmon
in the Davis Strait off the coast of west Greenland. The offshore
fishery catch increased from 36 metric tons in 1965 to more than 1,200
metric tons in 1969, and then gradually decreased.
The fact that large numbers of seabirds--almost entirely thick-billed
murres _(Uria lomvia)_--were being drowned in the salmon gill nets
was brought to the attention of the International Council for Bird
Preservation at its 15th World Conference in 1970. The Council's
recommendation was submitted to the Danish government and stated:
"... having noted that during the 1969 fishing season about 250,000
individuals of Brunnich's guillemot or thick-billed murre _(Uria
lomvia)_, a pelagic diving bird, were caught in these drift nets
and drowned, which number represents no less than 25 percent of the
Greenland population and exceeds its annual reproductive capacity;
urges the Danish Government, and the national governments of all other
countries involved in this fishing, to take all possible measures to
eliminate this very serious problem."
The figures in the recommendation were not supported by research; they
appeared instead to have been derived from the observed mortality on
an offshore fishery vessel in 1965, which was then related to the
salmon catch on that vessel and applied to the total catch of the
inshore fishery in 1964 (Anonymous 1969). Studies in 1969 and 1970 by
the Fisheries Research Board of Canada finally gave a firm basis for
the earlier, though poorly substantiated concern. On the basis of the
assumption that the ratio of salmon to murres caught in experimental
fishing applied to the commercial fishery, an estimate of an annual
mortality of 0.5 million murres (±50%) was made on the basis of a
salmon catch of 1,200 metric tons (Tull et al. 1972).
The birds being killed were from colonies in west Greenland, the
eastern Canadian Arctic, and possibly east Greenland and Spitzbergen.
Coupled with other known causes of mortality (particularly hunting
on the Greenland and Newfoundland coasts, an unknown but definitely
substantial kill from oil pollution, a calculated mortality of
pre-fledging young, and an unknown natural post-fledging mortality)
there is no doubt that the estimated annual production of 1.5 million
chicks from west Greenland and the Canadian Arctic was less than the
estimated total annual mortality (Tull et al. 1972). Thus, it comes as
no surprise that recent surveys of murre populations of west Greenland
and the Canadian Arctic have revealed massive declines in numbers
(Evans and Waterston 1976; D. N. Nettleship, personal communication).
It is therefore encouraging news that, as a result of an agreement
between the United States and Denmark, the offshore salmon gill-net
fishery was terminated at the end of the 1975 season. The inshore
fishery remained in operation, however, but was restricted to a total
annual salmon catch of 1,100 metric tons.
Pacific Offshore Salmon Gill-net Fishery
In the north Pacific Ocean, the Japanese gill-net fisheries for salmon
(_Oncorhynchus_ spp.), which have operated since 1952, might be
expected to have an even more destructive effect on seabirds, since the
annual salmon catch by the three Japanese salmon drift-net fisheries
was about one hundred times that in west Greenland in recent years. The
first, the mothership fishery, comprising about 369 catcher-boats[53]
serviced by 11 mother-ships, operates west of 175°W and generally north
of 46°N during the summer. The second, the land-based fishery of about
325 ocean-going vessels, operates west of 175°W and south of 46°N;
and the third, the coastal fishery, made up of about 1,380 short-haul
vessels, operates off Hokkaido. The relative salmon catches of these
three fisheries is on the order of 1:1.34:0.65.
Data collected on U.S. National Marine Fisheries Service research
vessels in 1974 (obtained through the cooperation of Francis M.
Fukuhara and Richard Bakkala, Northwest Fisheries Center, Seattle,
Washington) give, for the first time, an estimate of the magnitude of
the incidental seabird kill of the Japanese salmon gill-net fishery.
The kill data are available only from the mothership area and from an
area east of it to 165°W. The Japanese salmon fishery is restricted
to waters west of 175°W by agreement with the United States. Bird
kills from the other two areas may be estimated by the relative salmon
catch figures for the areas, assuming that seabird densities, species
composition, and catch effort are similar.
An estimate of the total kill of seabirds in the mothership area may
be made by calculating the bird mortality per length of gill-net set
by research vessels, multiplied by the total length of gill nets set
by the 369 catcher-boats of the Japanese mothership fishery. About
4,666 km of nets are set and retrieved daily during the approximately
65-day fishing season. The estimated annual mortality in the mothership
area is about 75,000 to 250,000 birds. The lower number is based on
data from 10 cruises (450 km of nets set) west of 175°W, within the
area of the mothership fishery. The higher number is based on data
from 20 cruises, including those in the first figure, west of 165°W,
and covering the period 18 April to 3 September 1974 (956 km of nets
set), whereas the mothership fishery usually operates between mid-May
and late July. Assuming similar seabird densities and catch per unit
of effort in the areas of the land-based and coastal fisheries, the
estimated annual mortality is between 214,500 and 715,000 birds. Since
1952, as many as 4.7 million birds may have been killed by the Japanese
salmon gill-net fishery. It must be stressed that seabird densities
and catch per unit of effort are not known to be similar for the areas
in question; consequently the projection of bird kill figures from one
area to all three is speculative.
In the mothership area and adjacent seas to the east, in addition to
murres (48% of birds killed), significant numbers of shearwaters,
_Puffinus_ spp. (27%); puffins (9%); and fulmars, _Fulmarus glacialis_
(5%) are killed, as are lesser numbers of small alcids, albatrosses
(_Diomedea_ spp.), and storm-petrels. The murres and puffins taken
in the mothership area are of U.S. and U.S.S.R. origin, and the
shearwaters come from New Zealand, Australia, and Chile. In the coastal
fishery area, Japanese and U.S.S.R. alcids are taken. Available
knowledge of the populations of the species making up the bulk of the
kill, which has been taking place for 20 years, is insufficient to
suggest whether their annual reproduction can tolerate such losses.
Prohibition of fishing within 160 km of North Pacific seabird breeding
islands would help to decrease losses of alcids of U.S. origin, but
would not help the shearwaters from the southern hemisphere.
Comparison of statistics of the salmon fisheries and associated bird
kills from the North Atlantic and the North Pacific shows that the
North Atlantic salmon fishery is concentrated in a relatively small
area which is also along a major migration pathway of murres. Virtually
all seabird mortality is confined to one species. Enough information is
at hand to indicate that this cause of mortality, in conjunction with
others known to be significant, is causing a drastic decline in the
thick-billed murre population.
In the North Pacific, on the other hand, the fishery is more widely
dispersed and the ratio of seabirds to salmon caught is much lower.
Furthermore, several species are subject to mortality. No information
is available to indicate whether alcid populations (which make up
two-thirds of the kill) are stable or decreasing. The shearwaters,
primarily sooty _(Puffinus griseus)_ and slender-billed _(P.
tenuirostris)_, appear to be able to sustain not only these losses but
also a sizable harvest of birds of the year (the so-called muttonbirds)
on their New Zealand and Australian breeding grounds. Thus, although
the latest estimates of the total standing stock of seabirds in the
North Pacific in summer may be as high as 100 million (Sanger and King,
this volume), and thus only about 1 of every 200 birds in the North
Pacific region may be caught, the fact that a few species, particularly
murres, are selectively caught raises questions about the impact of
this fishery on populations of these species.
The U.S.-Japan Migratory Bird Convention of 1973 specifically protects
all of the species thought to be subject to gill-net mortality in
the Pacific. Thus, the Japanese salmon fleet apparently operates in
constant violation of this convention.
Mortality of Albatrosses
A recent analysis of recoveries of Laysan albatrosses _(Diomedea
immutabilis)_ and black-footed albatrosses _(D. nigripes)_ banded on
the northwest Hawaiian chain from 1937 to 1969 showed that of a sample
of 532 recovered birds, 57.4% of the Laysan species and 49.5% of the
black-footed species were caught on fishhooks or in nets, and the means
of recovery of many additional birds was thought to have been the same
(Robbins and Rice 1974). It is likely that the large majority are taken
on Japanese and U.S.S.R. longline tuna fishing gear. Although this
cause of mortality is insignificant in terms of the total population
of either species (only 0.2% of banded Laysan and 0.8% of banded
black-footed albatrosses have been recovered by any means away from
their breeding grounds), these species are protected by the U.S.-Japan
Migratory Bird Convention. Furthermore, the possibility exists that
individuals of the endangered short-tailed albatross _(Diomedea
albatrus)_ might be killed in this manner.
Long-term Effects of Developing Capelin Fishery in Northwest Atlantic
Capelin are important food fish for many seabirds in the northwest
Atlantic, and the development and expansion of this fishery off
eastern Canada must be carefully monitored. In theory, the capelin
fishery ought not to seriously affect the birds because it is
designed to exploit a surplus of capelin artificially created by the
overfishing of Atlantic cod, the capelin's most important predator. It
is hoped that there is no prospect of the overfishing that may have
contributed to the recent drastic decline of the Peruvian anchovy
_(Engraulis ringens)_ and the seabird species dependent on it (Paulik
1971). However, the relative influence of overfishing and "El Niño"
oceanographic conditions on the decline remains unclear. North Atlantic
seabirds are, in any case, more versatile in their feeding habits
(Belopol'skii 1961). But, the threat may be a subtle one. The important
point to the seabirds may well be not merely the survival of a
reasonably large capelin stock, but the presence of capelin schools in
high densities in certain areas or at certain seasons. Lower densities
might, for example, reduce the foraging efficiency of breeding birds,
and hence their nesting success. The very large common murre colony
on Funk Island, Newfoundland (500,000 pairs: Tuck 1960), might be
particularly vulnerable. It lies close to an area where capelin are
especially abundant and one which is already being exploited by the
developing fishery.
References
Anonymous. 1969. Seabird slaughter. Sports Fish. Inst. Bull. 203:5.
Belopol'skii, L. O. 1961. Ecology of sea colony birds of the
Barents Sea. (Transl. from Russian.) Israel Program for
Scientific Translations, Jerusalem. 346 pp.
Biddy, C. J. 1971. Auks drowned by fishnets. Seabird Rep. No. 2.
Bourne, W. R. P. 1971. General threats to seabirds. ICBP [Int.
Counc. Bird Preservation] Bull. 11:200-219.
Brown, R. G. B., D. N. Nettleship, P. Germain, C. E. Tull, and
T. Davis. 1975. Atlas of eastern Canadian seabirds. Canadian
Wildlife Service, Ottawa. 220 pp.
Collins, J. W. 1884. Notes on the habits and methods of capture of
various species of seabirds that occur on the fishing banks off
the east coast of North America and which are used as bait for
catching codfish by New England fishermen. U.S. Comm. Fish Fish.
Rep. 1882:311-335.
Evans, P., and G. Waterston. 1976. The decline of the thick-billed
murre in Greenland. Polar Rec. 18:283-286.
Holgersen, H. 1961. On the movements of Norwegian _Uria aalge_. (In
Norwegian, English summary.) Sterna 4:229-240.
Lucas, F. A. 1890. Expedition to the Funk Island, with observations
on the history and anatomy of the Great Auk. Rep. U.S. Natl.
Mus., 1887-1888:493-529.
Murie, O. J. 1959. Fauna of the Aleutian Islands and Alaska
Peninsula. U.S. Fish Wildl. Serv., N. Am. Fauna 61. 406 pp.
Paulik, A. J. 1971. Anchovies, birds, and fishermen in the Peru
Current. Pages 156-185 _in_ W. W. Murdoch, ed. Environmental
Resources and Society. Sinauer Associates, Inc., Stamford, Conn.
Robbins, C. S., and D. W. Rice. 1974. Recoveries of banded Laysan
albatrosses _(Diomedea immutabilis)_ and black-footed albatrosses
_(D. nigripes)_. Pages 232-271 _in_ W. B. King, ed. Pelagic
studies of seabirds in the Central and Eastern Pacific Ocean.
Smithson. Contrib. Zool. 158.
Templeman, W. 1945. Observations on some Newfoundland seabirds.
Can. Field-Nat. 59:136-147.
Tuck, L. M. 1960. The murres. Canadian Wildlife Service, Ottawa.
260 pp.
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.
U.S. Department of the Interior, Alaska Planning Group. 1974. Final
environmental impact statement, proposed Alaska Coastal National
Wildlife Refuges. 678 pp.
FOOTNOTES:
[52] Present address: U.S. Fish and Wildlife Service, Office of
Biological Services--Coastal Ecosystems. 1011 E. Tudor Road, Anchorage,
Alaska 99503.
[53] This figure is based on data through 1971. Since then, the number
of catcher-boats has decreased to 332 in 1974 (F. M. Fukuhara, personal
communication).
Interactions Among Marine Birds and Commercial Fish in the Eastern
Bering Sea
by
Richard R. Straty and Richard E. Haight
National Marine Fisheries Service
Auke Bay Fisheries Laboratory
Auke Bay, Alaska 99821
Abstract
The high primary and secondary productivity
of the eastern Bering Sea makes it one of
the greatest producers of commercial fish
and largest congregating areas of marine
birds in the world. The fish and birds are so
interrelated that fluctuations in the abundance
of one may well be responsible for changes in
the abundance of the other. The seasonal and
annual variation in the impact of birds on fish
is a function of the life history, food habits,
growth rate, and final size of the fish species
of concern and of the distribution, abundance,
and feeding habits of bird populations--plus
the effects of the environment on these
factors. Stages in the life history of some of
the important commercial fish and shellfish
of the Bering Sea directly or indirectly
influenced by marine birds are identified.
The eastern Bering Sea is one of the world's richest fish-producing
areas and is also one of the world's major congregating areas for
marine birds. The large extent of the continental shelf and the
climatic and oceanographic characteristics of the eastern Bering Sea
combine to make this region extremely productive biologically. The
distribution and abundance of plankton, benthos, and fish determine the
distribution, time, and character of the migration of marine birds in
the eastern Bering Sea (Shuntov 1961). Several studies have illustrated
the close relation between marine birds and the biological properties
of surface waters (Tuck 1960; Bourne 1963; Solomensen 1965). Spatial
and temporal variations in the abundance of the fish families Clupeidae
(herring), Gadidae (codfish), Osmeridae (capelin), and Ammodytidae
(sand lance) are thought to be major determinants of the breeding
seasons, breeding places, and movements of boreal seabirds (Ashmole
1971). The timing of breeding among larids and alcids is related to the
seasonal changes in the surface waters inhabited by Ammodytidae and
Clupeidae in the North Sea (Pearson 1968).
The eastern Bering Sea contains members of these and other fish
families that are extensively exploited by man; the fish are also
important as forage for other species of commercial fish, marine
mammals, and marine birds. During some part of their life cycles, all
fish species feed on plankton, nekton, benthos, or other fishes.