probably are pelagic in the high arctic when 

 not breeding and have been found at extremely 

 high latitudes. The "Fram" expedition en- 

 countered them between 84°27' and 84°41' N 

 in July and August (Collett and Nansen, 

 1900). 



The species was present in the area of Bar- 

 row and along the coast to the study area, but 

 large flocks were observed only in the study 

 area (fig. 24). It was most common in the 

 northeast portion of the study area where the 

 ice coverage was greatest. This was the most 

 social of the gulls we observed and only 10 

 percent of the seventy 20-minute interval 

 counts were of single individuals (table III). 

 Flocks of approximately 120 birds were ob- 

 served on two occasions southwest of Icy Cape 

 and at one of the most westerly stations north- 

 west of Cape Lisburne (fig. 25). Approximately 

 one-half of all birds seen were immatures (fig. 

 26). Ross' Gull was absent from the Bering 

 Strait on 18 October. 



Some or all of the birds recorded by the 

 marine science technicians on the GLACIER 

 as Bonaparte's Gulls, Larus philadelvhia, or 

 Arctic Terns, Sterna paradisaea, that were 

 "following the ship" were most probably Ross' 

 Gulls. Bonaparte's Gull breeds north to Kotze- 

 bue Sound but has not been reported farther 

 north. The Arctic Tern breeds along the arctic 

 coast, but most leave Alaska on migration 

 toward southern hemisphere winter grounds by 

 early September. Sightings of this nature oc- 

 curred on 8, 17, 18, 19, and 20 September be- 

 tween 68°35' and 71°13'N, 164°13' and 

 167°43'W. 



We observed three different methods of feed- 

 ing by this species. Like other gulls, individuals 

 fed by hovering in the area of ice cakes while 

 in more open water they plunged to the surface. 

 Flocks sitting in leads in the ice were feeding 

 on the surface. One instance of an individual 

 hovering while feeding on Walrus dung was 

 observed. Arctic Cod and crustaceans appear 

 to be of about equal importance as food items 

 (table V). Three stomachs were examined in 

 detail. The amphipod Aphenisa glacialis was 

 the commonest crustacean found in the stom- 

 achs examined, with as many as 80 in one in- 

 dividual. Also present but in lesser numbers 

 were the large amphipods Atylus bruggeni, 

 Anonyx nugax and Gammarus locusta. One 



stomach contained portions of the exoskelton 

 of a beetle. Insects are the chief food during 

 the breeding season (Buturlin, 1906). Mal- 

 lophaga collected included both Saemundssonia 

 lari (0. Fabricius 1780) and Quadraceps 

 eugrammicus hryki (Timmermann 1952). 



Sabine's Gull (Xema sabinl) 



Sabine's Gull is circumpolar between 65° N 

 and 80° N in its breeding distribution and 

 breeds locally on the arctic coast of Alaska. In 

 summer, when there are few at-sea records, it 

 obtains most of its insect food by contact dip- 

 ping in tundra ponds while, after breeding, it 

 feeds on invertebrates cast up on the shore and 

 fish that it captures by contact dipping. Nelson 

 (1883) did not observe it in the Chukchi. 

 Jacques (1930) saw adults on 6 days during 

 August and juveniles on 23 and 25 August 

 south of Wrangel Island. Swartz (1967) re- 

 ported six scattered observations in the eastern 

 Chukchi. 



The species winters in the southern hem- 

 isphere, but there are surprisingly few records 

 of migrating birds for Alaska, although large 

 numbers of migrants are seen in fall off the 

 Oregon coast. This lead Gabrielson and Lincoln 

 (1959) to suggest that it stayed well offshore 

 while moving. Birds have been observed as late 

 as mid-September at Wainwright and 22 

 October at Barrow, but the bulk of migration 

 probably takes place earlier. 



We observed Sabine's Gull only in the area 

 of Barrow and Wainwright on September 23 

 and 24 (fig. 27). Eight flocks were observed 

 near ice cakes with the large.st flock containing 

 10 individuals. Our few observations suggest 

 that most individuals had already migrated 

 south and the lack of subsequent observations 

 indicates that migration, in this area at least, 

 takes place close inshore, contrary to Gabriel- 

 son and Lincoln's conclusion. 



Murres (C/naspp.) 



Two species of murres are found breeding 

 in the Chukchi Sea. The Thick-billed Murre 

 (Uria lomvia) is more northern in its distribu- 

 tion than the Common Murre (U. aalge). Both 

 species breed in the Bering Strait and at Cape 

 Thompson, while U. lomvia also nests at Herald 

 and Wrangel Islands, in small numbers near 

 Barrow and probably somewhere east of Bar- 

 row. Murres are the most abundant birds at 



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