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.