Pelagic Bird and Mammal Observations in the 

 Eastern Chukchi Sea, Early Fall 1970 



George E. Watson > and George J. Divoky - 



INTRODUCTION 



The Smithsonian Institution was invited to 

 make marine bird and mammal observations 

 during a U.S. Coast Guard ecological cruise off 

 the north slope of Alaska in early fall, 1970. 

 The purpose of the cruise was to gather base- 

 line data on the marine ecosy.stem in order to 

 evaluate the effects of pollution which may 

 occur as a consequence of development of the 

 Alaskan north slope. The icebreaker GLA- 

 CIER was deployed to the Beaufort Sea from 

 22 September to 18 October for the cruise. Ice 

 conditions in the western Beaufort Sea proved 

 so heavy in late September, however, that it 

 was decided to investigate an alternate area in 

 the eastern Chukchi Sea from Icy Cape to Cape 

 Lisburne. This region may likewise be de- 

 veloped for its mineral and petroleum re- 

 sources. The change in area of study proved a 

 happy one ornithologically since little was pre- 

 viously known of pelagic bird distribution in 

 the Chukchi and our fall, at-sea observations 

 are the latest in the season for the area. This 

 preliminary report on the pelagic birds and 

 mammals is intended to present distributional 

 and feeding data and to relate them to the 

 presence of ice and the timing of migration. 

 The preponderance of information collected 

 dealt with birds reflecting both the authors' 

 field of specialization and the relative abun- 

 dance of observations. 



PREVIOUS STUDIES ON MARINE BIRDS 

 AND MAMMALS 



The lack of shipping routes through the 

 Chukchi Sea has limited knowledge of the dis- 

 tribution and abundance of pelagic birds for 



' Chairman and ' Research Collaborator, Department 

 of Vertebrate Zoology, National Museum of Natural 

 History, Smithsonian Institution, Washington, D.C. 

 20560. 



this area. There are only three published ac- 

 counts of extensive at-sea obsei-vations. E. W. 

 Nelson (1883) entered the Chukchi aboard the 

 U.S. Revenue Cutter "Corwin" in late June 1881 

 and except for a short time in the Bering Sea, 

 stayed until 14 September of the same year. 

 His precise cruise course is not clear but he 

 visited the Siberian coast as far west as North 

 Cape including Herald and Wrangel Islands 

 and the Alaskan coast as far east as Barrow. 

 F. L. Jacques (1930) was in the Chukchi 

 aboard the schooner "Morrissey" from 30 July 

 to 25 August 1928 as part of the Stoll- 

 McCracken Expedition. Most of the cruise 

 track was south and east of Herald Island. His 

 most easterly position was approximately 

 164° W and the most northerly, 73° N. Swartz 

 (1967) published at-sea observations obtained 

 by E. J. Willoughby aboard the research vessel 

 "Brown Bear," from 6 August to 28 August 

 1960. Most of the cruise was south of Point 

 Hope and in the Kotzebue Sound area; only 

 seven legs were north of Cape Lisburne with 

 70° N being the most northerly position. 

 Swartz's detailed account is the only one of 

 the three that attempts to deal with observa- 

 tions on a quantitative basis. In addition to 

 these accounts Stresemann (1949) discussed 

 the birds observed and collected on Captain 

 Cook's last voyage. The "Resolution" and "Dis- 

 covery" were in the Chukchi from 11 August 

 to 3 September 1778 and from 5 July to 31 July 

 1779. Cook sailed up both the Siberian and 

 Alaskan coasts until he encountered ice. An 

 expedition from Harvard University, aboard 

 the power schooner "Polar Bear," sailed 

 through the Chukchi Sea from Cape Serdze, 

 Siberia to Cape Lisburne, and thence north to 

 Point Barrow in July, 1913. Brooks (1915) 

 and Dixon (1943) reported extensively on land 

 observations in Siberia and on the north slope 

 of Alaska before and after their Chukchi cross- 



Ill 



