Habitats for breeding marine birds are found along much of the 4,100-km coastline of Alaska that fronts on the Chukchi and Bering seas. Seasonal sea ice and an extensive outer continental shelf are dominant features that contribute to the productivity of these marine waters, which sustain populations of fishes, birds, and mammals that are of considerable and diverse values to man (Kelley and Hood 1974).
Our purpose in this paper is to describe the distribution, abundance, and relative status of some of the nearly 100 species of marine birds breeding within this region and the information base from which the descriptions are derived. Although the selection is admittedly arbitrary, we discuss mainly the colonial nesting species because they are generally in greater jeopardy from lost breeding habitat and from catastrophes than are the species that are widely dispersed or solitary in nesting. Because we believe matters affecting the conservation of marine birds will be geographically oriented, we discuss the status and distribution of breeding birds on that basis, rather than by the more traditional taxonomic approach. We use the terms "colony" and "colonies" somewhat loosely and interchangeably to include any aggregation of birds of the same or different species nesting in proximity to each other, even those on the same island or headland, although populations may be miles apart and occupy different kinds of habitats. The nature of this paper and the scale of our maps do not allow for detailed resolution of each colony's location (for the most part this information is not available), but rather facilitates a general impression of status.
Most place-names used by us are shown in Fig. 1; the others may be located by referring to Orth's (1967) gazetteer on Alaska.
Information Base
There is no adequate catalog of marine bird colonies and other avian habitats for the Bering-Chukchi region or for Alaska as a whole. King and Lensink (1971) described the waterfowl populations and major lowland habitats of the State and listed only a few of the many colonies of cliff-nesting birds. LeResche and Hinman (1973) identified a few additional colonies, provided fragmentary information on composition and abundance at some of these sites, and delineated areas of wetland habitats on maps in their statewide atlas on wildlife. General and occasionally site-specific information on the location, but rarely on population size and composition, of colonies can be gleaned from the 321 species accounts presented by Gabrielson and Lincoln (1959) and from the general works by Bent (1919, 1921, 1922, 1923, 1925, 1927, 1929), Dement'ev and Gladkov (1951), Dement'ev et al. (1951, 1952), Palmer (1962), Fisher (1952), Tuck (1960), and others. The birds on the Asiatic side of these waters, which are not treated in this paper, were described by Portenko (1973).
Information on the status of waterfowl in the region is generally more detailed than that for most other groups of birds because waterfowl have been the object of systematic surveys since the late 1940's as part of the continent-wide effort to manage populations for sport hunting. Because the emphasis of these surveys has been directed toward the species of ducks important to hunters in the "lower 48" States, data are not adequate to measure changes in populations for most sea ducks and marine geese nesting in this region. These surveys have, however, enabled biologists to delineate waterfowl habitats and make reasonable estimates of populations for some of the more abundant and conspicuous species (King and Lensink 1971; U.S. Fish and Wildlife Service [FWS] 1973c; U.S. National Park Service [NPS] 1973).
Chukchi Sea Coast
A disproportionate percentage of ornithological investigations in arctic Alaska have centered about Barrow, where ornithologists were attracted because of the propensity of vagrant birds to collect there and because of the above average facilities, conveniences, and transportation afforded first by the whaling station, then by the military, and later by a research laboratory. Recent petroleum development near Prudhoe Bay has resulted in a somewhat commensal eastward shift in ornithological studies.
Bailey (1948), Gabrielson and Lincoln (1959), and Pitelka (1974) reviewed much of the published information on arctic avifauna, including that of the Chukchi coast. Selkregg [1975] mapped various avian habitats, ascribed either relative or absolute values for the population size of certain groups of birds, and included a selected bibliography that did not entirely duplicate those provided by the other reviewers. Watson and Divoky (1975) described the avifauna of Alaska's Beaufort Sea coast, which is much the same as that of the Chukchi coast from Point Barrow south to Cape Lisburne (both coasts are of low relief).
Intensive studies near Barrow have done much to characterize the behavior, productivity, and ecological requirements of calidridine sandpipers (Pitelka 1959; Pitelka et al. 1974; Holmes 1970, 1971) and, to partly explain the cyclical relationships between jaegers (Stercorarius spp.) and their prey (e.g., Pitelka et al. 1955; Maher 1974). Quantitative estimates of certain bird populations at Cape Thompson (Swartz 1966; Williamson et al. 1966), Little Diomede (Kenyon and Brooks 1960), and on the coastal lowlands of the Seward Peninsula (King and Lensink 1971; U.S. NPS 1973), and for black guillemots (Cepphus grylle) throughout the region (Divoky et al. 1974) are among the best data on status of marine birds for any locality in Alaska. Grinnell (1900a) described the birds he observed in the Kotzebue Sound area.