MARINE BIRDS OF THE CHUKCHI AND BERING SEAS 



25 



Studies of particular species of marine birds 

 on the delta (again, all in the general vicinity 

 of Hooper and Hazen bays) were reported by 

 Hansen and Nelson (1957) and Shepherd 

 (1960) for black brant (Branta bernicla), by 

 Headley (1967) and Eisenhauer and Kirk- 

 patrick (1977) for emperor geese (Anser cana- 

 gica), by Dau (1974) and Mickelson (1975) for 

 spectacled eiders (Somateria fischeri), by 

 Petersen (1976) for red-throated loons (Gavia 

 stellata), and by Holmes (1970, 1971, 1972) for 

 dunlins (Calidris alpina) and western sand- 

 pipers (C. mauri). 



Birds of Nunivak Island were reported by 

 Swarth (1934), but the importance of the 

 island to marine birds was not put into proper 

 perspective until the Nunivak National Wild- 

 life Refuge was evaluated for designation as a 

 wilderness area (U.S. FWS 1972). 



The Pribilof Islands have served as a focal 

 point for ornithological investigations of the 

 Bering Sea in much the same way that Bar- 

 row has for the Arctic. The avifauna of the 

 Pribilofs has been described by Coues (1874), 

 Elliott (1882), Palmer (1899), Hanna (1918), 

 Preble and McAtee (1923), Gabrielson and 

 Lincoln (1959), Kenyon and Phillips (1965), 

 and a host of others that mainly added new 

 species to the record list. Although most of 

 these ornithologists marveled at the numbers 

 of birds, information is lacking from which 

 most changes in populations can be noted. 

 (An exception is the record of common and 

 thick-billed murres, Uria aalge and U. lomvia, 

 which formerly nested in such abundance on 

 Walrus Island that annually several tons of 

 eggs were gathered for consumption by resi- 

 dents of the islands [Palmer 1899], but were 

 greatly reduced in numbers by the summer of 

 1973, when J. C. Bartonek, J. G. King, G. J. 

 Divoky, and D. T. Montgomery observed only 

 a few thousand murres on a small portion of 

 the island. Most of the suitable nesting sites, 

 especially the flat areas often used by com- 

 mon murres, were occupied by Steller's sea 

 lions, Eumetopias jubata, which, apparently 

 because of reduced hunting pressure, occu- 

 pied the island and displaced the murres.) 



For some unexplained reason the numerous 

 and large marine bird colonies along the north 

 side of Bristol Bay appear to have been 

 largely overlooked until recent years (Bar- 

 tonek and Gibson 1972). Gabrielson and 



Lincoln (1959) summarized the few observa- 

 tions by Osgood (1904) and Turner (1886) in 

 this area, but obviously were unaware that, in 

 aggregate, these colonies rival those of the 

 Pribilofs. Dick and Dick (1971) made an 

 exemplary study of marine birds and their 

 numbers at Cape Peirce and on nearby Shaiak 

 Island. Murie (1959) provided annotated re- 

 marks on marine birds of Amak Island, but 

 not of nearby Sealion Rocks. 



Status and Distribution 



Seven groups of colonies of cliff-, burrow-, 

 and crevice-nesting birds are found on the 

 headlands and islands in the coastal region, 

 each numbering more than 1 million birds; 

 nine colonies range downward to 100,000 

 birds; and a host of others range downward to 

 1,000 birds (Fig. 2). Unestimated numbers of 

 other marine birds nest on the lowlands about 

 Kotzebue Sound, the Yukon-Kuskokwim 

 delta, and Bristol Bay, but are not shown in 

 Fig. 2. The occurrence at colonies of 20 of the 



Colony Size: 



. >100 

 >1,000 

 >10,000 



>100,000 



Fig. 2. Relative numbers of marine birds at colonies 

 in different localities, without regard to species 

 composition or breeding status. 



