Table 7.Nest-site preference for seabirds breeding from Cape Fairweather, Alaska, to the Columbia River, Washington.Nest-site typeBird speciesBurrow-rock creviceDiurnalPigeon guillemotHorned puffinTufted puffinNocturnalFork-tailed storm-petrelLeach's storm-petrelKittlitz's murreletAncient murreletCassin's aukletRhinoceros aukletOpen nestsFlat or slopeDouble-crested cormorantBrandt's cormorantGlaucous-winged gullHerring gullWestern gullBlack oystercatcherCliff facePelagic cormorantCommon murreBlack-legged kittiwakeTree branchMarbled murrelet
Northern and southern British Columbia provide another good example of habitat availability as revealed through seabird population estimates. The population data are more comprehensive and have largely been gathered by island visitations. The islands in the northern portion are heavily vegetated and many have well-developed soil into which storm-petrels, auklets, and murrelets can burrow. Indeed, 96% of the seabird population consists of nocturnal, burrow-nesting species. In southern British Columbia, however, there are more open-nest species, particularly glaucous-winged gulls and cormorants.
Overall, 68% of the breeding seabirds found along the northeastern Pacific coast are nocturnal and nest in burrows or rock crevices (Table 8). The most conspicuous nesting birds such as gulls, cormorants, and murres, comprise only 22% of the total population. Consequently, our current estimates of breeding seabirds still underestimate the more secretive, nocturnal, burrow-nesting species.
Table 8.Proportional nest-site preferences of Pacific coast seabirds.[11]SiteEstimated number of pairsPercent of populationTotalBritish ColumbiaSan Juan IslandsWashington coastBritish ColumbiaSan Juan IslandsWashington coastNorthernSouthernNorthernSouthernPopulationPercentBurrow-rock creviceDiurnal1,84911,3342317,5042.018.11.417.320,9189.7Nocturnal90,34730,6009,80017,07096.048.958.639.4147,81768.1Open nestsFlat or slope90915,1016,2985,7551.024.237.613.328,06313.0Cliff face9825,52539512,9451.08.82.430.019,8479.2Total94,08762,56016,72443,274216,645
The available data are inadequate to detect changes in population distribution and density for most species (Table 9). In Washington, for instance, limited unsubstantiated information suggests an overall decline of the double-crested cormorant and tufted puffin in the San Juan Island area. Likewise, there seems to be an increase in glaucous-winged gulls there. In British Columbia, Drent and Guiguet (1961) were able to detect changes in some species. For example, they noted increases in the double-crested cormorant, pelagic cormorant, and glaucous-winged gull. No change was observed in the tufted puffin. Since then, the Brandt's cormorant has established a colony in Barkley Sound (Guiguet 1971). The data in southeastern Alaska are inadequate for all species except, perhaps, the Cassin's auklet which Gabrielson and Lincoln (1959) reported to be declining throughout Alaska. In short, no definitive statements can now be made concerning changes in seabird population numbers.
Storm-petrels are especially difficult to census because they are nocturnal, and the burrows and rock crevices where they breed are often difficult to locate, especially in mixed-species colonies. The census data are inadequate to determine whether there have been changes in population density and distribution. Indeed, the biology of this species is perhaps the least known of the North Pacific colonial seabirds. In southeastern Alaska, this species is outnumbered by at least 5 to 1 by the Leach's storm-petrel(Oceanodroma leucorhoa). The reasons for this are poorly understood. There is some evidence that the numbers of breeding fork-tailed storm-petrels on Forrester Island may fluctuate drastically from one year to the next (Gabrielson and Lincoln 1959).
Of the two subspecies of this petrel (O. l. leucorhoaandO. l. beali), onlyO. l. bealiis found in southeastern Alaska. Theleucorhoasubspecies is more northerly in distribution. Where both fork-tailed and Leach's storm-petrels are sympatric, Leach's predominates; however, this relationship becomes more unpredictable in British Columbia and Washington. This species is undoubtedly widespread in the forested islands of the Alexander Archipelago.
The double-crested cormorant apparently does not breed in southeastern Alaska since Willett (1912), Gabrielson and Lincoln (1959), and S. Patten (personal communication) do not report breeding colonies for the area. The largest populations occur in southern British Columbia principally in the Gulf Islands, where 71% of all breeding double-crested cormorants are found (Table 10). According to Jewett et al. (1953), this species was less common in Puget Sound than was Brandt's cormorant, but is certainly not the case today (D. A. Manuwal, unpublished data). The only common cormorants in the San Juan Islands are the pelagic and double-crested species. The double-crested cormorant seems to have declined in numbers on both coastal and inland waters. On the basis of his observations, R. W. Campbell believes that this species is increasing in British Columbia.
Table 9.Distribution and status of marine birds breeding along the Pacific coast of Washington, British Columbia, and southeastern Alaska.(X = known to breed in the region;? = data insufficient; + = evidence indicates an overall increase in size of population; - = evidence indicates an overall decrease in size of population; 0 = no population change.)Family and speciesCommon nameWashingtonBritish ColumbiaSoutheastern AlaskaPresenceStatusPresenceStatusPresenceStatusHydrobatidaeOceanodroma furcataFork-tailed storm-petrelX?X?X?O. leucorhoaLeach's storm-petrelX?X-X?PhalacrocoracidaePhalacrocorax auritusDouble-crested cormorantX-X-P. penicillatusBrandt's cormorantX?X0?P. pelagicusPelagic cormorantX?X+X?HaematopodidaeHaematopus bachmaniBlack oystercatcherX?X+X?LaridaeLarus glaucescensGlaucous-winged gullX+X+X?L. occidentalisWestern gullX?X?L. argentatusHerring gullX?Rissa tridactylaBlack-legged kittiwakeX?AlcidaeUria aalgeCommon murreX?X-X?Cepphus columbaPigeon guillemotX?X+X?Brachyramphus marmoratusMarbled murreletX?X?X?B. brevirostrisKittlitz's murreletX?Synthliboramphus antiquusAncient murreletX?X?Ptychoramphus aleuticusCassin's aukletX?X?X-Cerorhinca monocerataRhinoceros aukletX?X+X?Fratercula corniculataHorned puffinX?Lunda cirrhataTufted puffinX-X0X?Total species141516
Brandt's cormorant is the least abundant of the three cormorant species that nest in the study area. Washington is at the northernmost edge of the breeding distribution of this species. Only one more northerly colony exists, on Sartine Island off Vancouver Island (Vermeer et al. 1976). Brandt's cormorant comprises about 85% of the cormorant population in Oregon (U.S. Fish and Wildlife Service, unpublished data). However, in Washington it is only about 9% and in British Columbia 3% of the total cormorant population.
Table 10.Estimated seabird populations breeding from Cape Fairweather, Alaska, to the Columbia River, Washington.[12][13][14](? = present in unknown numbers; - = inadequate data.)Bird speciesNorthern British ColumbiaSouthern British ColumbiaSan Juan IslandsWashington coastTotal all regionsPopulationPercentPopulationPercentPopulationPercentPopulationPercentPopulationPercentFork-tailed storm-petrel49,08052.2?-0-1,9004.450,98023.5Leach's storm-petrel1,3651.55,0008.00-3,6558.510,0204.6Double-crested cormorant0-1,0581.764>0.1390>0.11,512>0.1Brandt's cormorant0-185>0.10-140>0.1325>0.1Pelagic cormorant9821.04,0176.43952.49952.36,3893.0Glaucous-winged gull9091.013,85822.26,23437.34,2159.825,21611.6Western gull0-?-0-9302.2930>0.1Common murre0-1,5082.40-11,95027.713,4586.2Pigeon guillemot1,7331.81,2562.01941.2161>0.13,3451.5Ancient murrelet21,17722.50-0-0-21,1779.8Cassin's auklet13,47514.325,00040.00-100>0.138,57517.8Rhinoceros auklet5,2505.66,000>0.19,80058.611,41526.427,06512.5Horned puffin0-0-0-0-0-Tufted puffin116>0.110,07816.137>0.17,34317.017,5748.1Total94,08767,96016,72443,194216,566
Comparing information in Jewett et al. (1953) with the current situation, it is apparent that there has been a drastic change in the distribution and probably in the numbers of this species in Washington. Today, there are no Brandt's cormorant colonies in the San Juan Islands or Strait of Juan de Fuca. Yet Jewett et al. (1953) reported colonies at Bellingham Bay and on Lopez and Matia islands. We have observed juvenile Brandt's cormorants in the San Juan Islands during the summer. This species may be particularly susceptible to human disturbance, since all three areas listed above are heavily used in the summer for recreation.
The distribution of breeding colonies of the pelagic cormorant is strongly determined by the availability of the steep cliffs on which it constructs its nest. This is the only common cormorant in southeastern Alaska. Throughout its extensive range, this species is generally found breeding in small numbers. Nothing is known about fluctuations in its numbers in Alaska.
This species is common in both British Columbia and Washington; nesting sites are of the same type as those in Alaska except in the San Juan Islands, where 200-300 birds nest on cliff faces composed of glacial deposits. Here, there is frequent nest loss due to slippage off the cliff face; this loss is especially severe on Smith and Protection islands. There do not appear to be any changes in the distribution of pelagic cormorants, but an accurate assessment of abundance is impossible from the data currently available.
The glaucous-winged gull is the characteristic gull of southeastern Alaska and British Columbia. In Washington, it is the dominant gull in the San Juan Island area but interbreeds with the western gull on the Washington outer coast from Tatoosh to Copalis Beach (Scott 1971). In Alaska, it is widely distributed and locally abundant on Forrester Island, St. Lazaria, and throughout Glacier Bay (S. Patten, personal communication). The biology of this species has been extensively studied in the southern part of its range, especially by Vermeer (1963) and James-Veitch and Booth (1954). The only study of the breeding biology of this species in southeastern Alaska is by Patten (1974) for Glacier Bay. Glaucous-winged gulls are apparently increasing in British Columbia (R. W. Campbell, unpublished data) and in Washington (T. R. Wahl, personal communication). This increase is undoubtedly a result of the proximity of breeding colonies to garbage dumps and commercial fishing fleets in both Canada and the United States. Little is known about changes in populations of gulls in southeastern Alaska.
The western gull is the common breeding gull of the Washington outer coast; however, there is increased interbreeding with glaucous-winged gulls northward from Destruction Island to Tatoosh Island. The percentage of glaucous-winged gulls steadily increases until Vancouver Island and the Strait of Juan de Fuca, where western gulls are rare. Population estimates of gulls on the outer coast of Washington are derived primarily from aerial flights. This makes identification of gulls difficult, and in view of the amount of interbreeding, it is probably impossible to classify many of the breeding gulls as to species. Western gulls appear to be increasing in the Grays Harbor area (G. D. Alcorn, personal communication).
The herring gull is typically found in inland Alaska but can be found uncommonly along the coast of southeastern Alaska, where it often forms mixed colonies with glaucous-winged gulls. These two species apparently hybridize where they are sympatric (Williamson and Peyton 1963; Patten and Weisbrod 1974; Patten 1974).
The black-legged kittiwake is found only in the northern portions of southeastern Alaska. It apparently is a common breeding bird in Glacier Bay National Monument (S. M. Patten, Jr., personal communication). No population estimates are available for this species other than that it is locally abundant.
Common murres are common in southeastern Alaska and the coast of Washington but breed only in small numbers in British Columbia and are absent in the San Juan Islands. Since this species usually prefers cliffs or the tops of inaccessible rocks, they are probably limited by island topography in British Columbia, and are most certainly so limited in the San Juan and Gulf Island groups.
In Alaska, common murres breed in unknown numbers in Glacier Bay and in large numbers on St. Lazaria, Forrester, and the Hazy islands. No data on population changes are available for any of the three regions.
The pigeon guillemot is common throughout the region from Cape Fairweather to Washington. Even though it is not truly colonial, it may be locally abundant where there are suitable nest sites. Since these nest sites are usually difficult to find, population estimates are seldom accurate, usually being conservative. It is evident that guillemots appear to be small in number when compared with other seabirds nesting at major colony sites in the north Pacific region (Table 10). This disparity may be exaggerated by the difficulty of censusing guillemots.
Since the marbled murrelet has been found to nest in coniferous forests (Binford et al. 1975), traditional census techniques are unsuitable. This species is common in southeastern Alaska (Gabrielson and Lincoln 1959), in British Columbia (Drent and Guiguet 1961), and in Washington (Jewett et al. 1953).
The difficulties in assessing breeding populations of Kittlitz's murrelet are the same as those for the marbled murrelet. This species nests on the ground at high elevation near the coast (Bailey 1973). The largest concentrations are in the vicinity of Glacier Bay National Monument (Gabrielson and Lincoln 1959). They are not found breeding in Washington or British Columbia.
Ancient murrelets appear to be locally common throughout southeastern Alaska. Their presence is probably strongly dependent upon a suitable soil in which to excavate burrows. The only available population estimates are those by Willett (1915) for Forrester Island (Table 1). Censusing this species is especially difficult because its burrows are easily confused with those of Cassin's auklet. There are no studies of this species in southeastern Alaska; however, it has been well studied in the Queen Charlotte Islands to the south by Sealy (1975).
A synthesis of literature and unpublished observations led Gabrielson and Lincoln (1959) to conclude that Cassin's auklet has greatly decreased in numbers and is not abundant anywhere in Alaska. They also concluded that the colony on Forrester Island (Table 1) was the only well-documented colony in southeastern Alaska. Fishermen in the southeastern Alaska area occasionally see this species (M. E. Isleib, personal communication), but it is apparently still uncommon though more widespread than just Forrester Island. The nocturnal habits and burrowing in dense vegetation makes censusing this species very difficult. Nothing is known about the ecology of this species in Alaska.
Rhinoceros auklets seem to be found breeding only on islands where there is a well-developed soil in which to excavate their extensive burrows. From the limited evidence available, it appears that the largest rhinoceros auklet populations probably are to be found in southeastern Alaska. Willett (1912) found a very large population on Forrester Island (Table 2), and the species has been found in the summer in the Barren Islands east of Kodiak Island (E. P. Bailey, personal communication). More intensive surveys of the Alexander Archipelago will probably reveal other populations of this species.
This species is less common in British Columbia than either Alaska or Washington. A possible reason for this is lack of suitable nesting areas. In Washington, the two largest colonies are at Protection Island in the Strait of Juan de Fuca and Destruction Island on the outer coast. Smaller numbers exist on other coastal islands and on Smith Island in the Strait of Juan de Fuca. The Smith Island colony is an interesting one since it appears that early human disturbance in the late 19th or early 20th century eliminated the species from the island. In their discussion of Smith Island, Jewett et al. (1953) made no mention of auklets, only of puffins and guillemots. Couch (1929) did not record the species in 1925. The colony now numbers about 600 pairs.
Although the horned puffin is one of the most abundant seabirds in other parts of Alaska, it is much less abundant in the southeastern portion. In addition to the information discussed by Sealy (1973), it now appears that this species may breed as far south as Triangle Island, British Columbia (K. Vermeer, personal communication; D. A. Manuwal, personal observation). Here, as on Forrester Island, it is greatly outnumbered by the tufted puffin. No data are available on the breeding or status of this species in the study area.
The tufted puffin is found breeding on scattered islands throughout the region. The largest known colonies are on Forrester Island, Alaska, Triangle Island, British Columbia, and Carroll Island, Washington. It is notably absent from most of the gulf and San Juan Islands. Even though puffins have apparently never been numerous in the San Juan Islands, their population has noticeably declined during the past 35 years. For example, Jewett et al. (1953) reported a colony of 50 pairs on Bare Island in 1937, but in 1973 only 2 pairs were counted (D. A. Manuwal, unpublished data). Likewise, in 1915 there were more than 250 pairs on Smith Island, but by 1916 there were only 75 pairs (Jewett et al. 1953). The decline is attributed to rapid erosion of the glacial-deposit cliffs. There are no puffins on Smith Island today, and the largest colony in the Puget Sound area is the 35 pairs on Protection Island (D. A. Manuwal, unpublished data).
The total minimum estimate of the breeding seabird populations of British Columbia and Washington is 216,500 pairs (Table 10). No comprehensive estimates are available for breeding seabirds of southeastern Alaska. It is likely, however, that the number of breeding seabirds in the Alexander Archipelago may be equal to (or exceed) the populations of both British Columbia and Washington. Data are desperately needed from that area. Of the total seabird population in the study area (Table 10) 43% reside in northern British Columbia. The Washington State population represents 28% of the total. Fork-tailed storm-petrels comprise almost 25% of all the breeding seabirds in the area under consideration. The Cassin's auklet is the next most numerous species (18% of the total).
It is apparent that current data are, for the most part, inadequate for assessing anything but catastrophic changes in seabird breeding colonies. This inadequacy is due to inadequate censusing because of excessive reliance upon aerial surveys; in the past, this has often been a result of insufficient funding.
Of the several threats facing seabird populations, none may be as important as oil pollution. A general review of this subject is presented elsewhere by Vermeer and Vermeer (1975). It is apparent from this review that the most vulnerable species are those that dive beneath the sea surface, including all the alcids and cormorants breeding along the coast that are discussed in this paper. This group makes up almost 60% of all the breeding seabirds in this area. Unfortunately, our knowledge of several of these species is scanty and our current census techniques are unsuitable for most of these birds.
Studies of the changes in seabird numbers have been made in other oceans. For example, in Great Britain (Bourne 1972a, 1972b; Harris 1970), eastern Canada (Nettleship 1973), and the Atlantic coast of the United States (Kadlec and Drury 1968), two major trends seem apparent. First, there is an overall decline inalcid and tern numbers. The decline in auks may be due to their extreme vulnerability to oil pollution (Bourne 1972a, 1972b; Vermeer and Vermeer 1975). The Atlantic puffin, however, may be suffering the additional effects of gull cleptoparasitism (Nettleship 1972). Secondly, there seems to be an increase in gull populations on both sides of the Atlantic, particularly the herring gull and black-legged kittiwake.
Compared with the Atlantic coast of North America and northern Europe, the data base for seabird populations of the Pacific coast is poor. The fragmentary evidence now available indicates that there may be small population increases in the western and glaucous-winged gulls and range extensions of the Brandt's and double-crested cormorants and of the rhinoceros auklet (Scott et al. 1974). Whether these changes represent actual population increases or displacements remains unclear. The remote locations of most of the large Pacific seabird colonies may provide unofficial protection from human interference. Intensive surveys are needed to establish base-line inventories in these areas.
As a consequence of this first comprehensive review of the status of breeding marine birds of the northeast Pacific coast of North America, we recommend the following future research topics as necessary for the conservation of this great international resource.
• Seabird colony census techniques should be refined since almost 68% of the seabirds in this area are nocturnal and nest in burrows. The present reliance on aerial censusing, although economical, is inadequate to census most breeding seabird populations; more on-site surveys are needed. For surface-nesting species and diurnal, burrowing species, studies on species specific activity cycles are needed so that census data can be corrected for birds not observed at the colony. For nocturnal, burrowing species seasonal burrow occupancy rates must be determined so that burrow counts can be corrected for inactive burrows.• Comprehensive surveys should be made every 3-5 years.• In 1980 a coordinated breeding bird survey of the entire Pacific coasts of Mexico, Canada, and the United States should be conducted.• Specific islands where key populations exist should be carefully monitored for subtle changes in population density or species composition.• Increased study of the breeding biology of seabirds should be carried out so that base-line reproductive characteristics can be determined.• Detailed studies of the effects of human disturbance should be made, especially for species that breed near large coastal cities or marine recreation areas.
• Seabird colony census techniques should be refined since almost 68% of the seabirds in this area are nocturnal and nest in burrows. The present reliance on aerial censusing, although economical, is inadequate to census most breeding seabird populations; more on-site surveys are needed. For surface-nesting species and diurnal, burrowing species, studies on species specific activity cycles are needed so that census data can be corrected for birds not observed at the colony. For nocturnal, burrowing species seasonal burrow occupancy rates must be determined so that burrow counts can be corrected for inactive burrows.
• Comprehensive surveys should be made every 3-5 years.
• In 1980 a coordinated breeding bird survey of the entire Pacific coasts of Mexico, Canada, and the United States should be conducted.
• Specific islands where key populations exist should be carefully monitored for subtle changes in population density or species composition.
• Increased study of the breeding biology of seabirds should be carried out so that base-line reproductive characteristics can be determined.
• Detailed studies of the effects of human disturbance should be made, especially for species that breed near large coastal cities or marine recreation areas.
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Bailey, E. P. 1973. Discovery of a Kittlitz's murrelet nest. Condor 75:457.
Binford, L., B. Elliott, and S. Singer. 1975. Discovery of a nest and the downy young of the marbled murrelet. Wilson Bull. 87:303-319.
Bourne, W. 1972a. The decline of auks in Great Britain. Biol. Conserv. 4:144-146.
Bourne, W. 1972b. Threats to seabirds. Int. Counc. Bird Preserv. Bull. XI:200-218.
Couch, L. 1929. Introduced European rabbits in the San Juan Islands, Washington. J. Mammal. 10:334-336.
Drent, R. H., and C. Guiguet. 1961. A catalogue of British Columbia seabird colonies. Occas. Pap. B. C. Prov. Mus. 12. 173 pp.
Franklin, J., and C. Dyrness. 1973. Natural vegetation of Oregon and Washington. U.S. For. Serv. Gen. Tech. Rep. PNW-8. 417 pp.
Gabrielson, I., and F. Lincoln. 1959. The birds of Alaska. The Stackpole Company, Harrisburg, Penn., and Wildlife Management Institute, Washington, D.C. 922 pp.
Grinnell, J. 1897. Petrels of Sitka, Alaska. Nidologist 4:76-78.
Grinnell, J. 1898. Summer birds of Sitka, Alaska. Auk 15:122-131.
Grinnell, J. 1909. Birds and mammals of the 1907 Alexander Expedition to southeastern Alaska. Univ. Calif. Publ. Zool. 5:171-264.
Guiguet, C. 1971. A list of seabird nesting sites in Barkley Sound, British Columbia. Syesis 4:253-259.
Harris, M. P. 1970. Rates and causes of increases of some British gull populations. Bird Study 17:325-335.
Heath, H. 1915. Birds observed on Forrester Island, Alaska during the summer of 1913. Condor 17:20-41.
James-Veitch, E., and E. Booth. 1954. Behavior and life history of the glaucous-winged gull. Walla Walla Coll., Publ. Biol. 12.
Jewett, S., W. Taylor, W. Shaw, and J. Aldrich. 1953. Birds of Washington State. Univ. of Washington Press, Seattle. 767 pp.
Kadlec, J., and W. Drury. 1968. Structure of the New England herring gull population. Ecology 49:644-676.
Kenyon, K., and V. Scheffer. 1961. Wildlife surveys along the northwest coast of Washington. Murrelet 42:29-37.
Manuwal, D. A. 1974. Conservation notes (Protection Island). Pac. Seabird Group Bull. 1.
Nettleship, D. 1972. Breeding success of the common puffin (Fratercula arcticaL.) on different habitats at Great Island, Newfoundland. Ecol. Monogr. 42:239-268.
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FOOTNOTES:[5]Data are minimum estimates of pairs and do not include breeding sites with less than 100 birds.[6]Does not include the black oystercatcher, marbled murrelet, and western gull.[7]Estimates only for colonies of 100 or more birds.[8]Estimates are in number of pairs.[9]Estimates are number of pairs.[10]Estimates are numbers of pairs.[11]Data for southeastern Alaska were inadequate to enable estimates of breeding pairs.[12]Population estimates are minimum and represent numbers of pairs.[13]Does not include the following species for which population estimates are lacking: black oystercatcher, herring gull, black-legged kittiwake, marbled murrelet, Kittlitz's murrelet.[14]Data for southeastern Alaska were inadequate to enable estimates of breeding pairs.
[5]Data are minimum estimates of pairs and do not include breeding sites with less than 100 birds.
[5]Data are minimum estimates of pairs and do not include breeding sites with less than 100 birds.
[6]Does not include the black oystercatcher, marbled murrelet, and western gull.
[6]Does not include the black oystercatcher, marbled murrelet, and western gull.
[7]Estimates only for colonies of 100 or more birds.
[7]Estimates only for colonies of 100 or more birds.
[8]Estimates are in number of pairs.
[8]Estimates are in number of pairs.
[9]Estimates are number of pairs.
[9]Estimates are number of pairs.
[10]Estimates are numbers of pairs.
[10]Estimates are numbers of pairs.
[11]Data for southeastern Alaska were inadequate to enable estimates of breeding pairs.
[11]Data for southeastern Alaska were inadequate to enable estimates of breeding pairs.
[12]Population estimates are minimum and represent numbers of pairs.
[12]Population estimates are minimum and represent numbers of pairs.
[13]Does not include the following species for which population estimates are lacking: black oystercatcher, herring gull, black-legged kittiwake, marbled murrelet, Kittlitz's murrelet.
[13]Does not include the following species for which population estimates are lacking: black oystercatcher, herring gull, black-legged kittiwake, marbled murrelet, Kittlitz's murrelet.
[14]Data for southeastern Alaska were inadequate to enable estimates of breeding pairs.
[14]Data for southeastern Alaska were inadequate to enable estimates of breeding pairs.