48 BULLETIN 113, UNITED STATES NATIONAL MUSEUM. 



accomplished by a quiver of the wings on the part of one of the two, a slight 

 rise as the other passed beneath, and then a similar descent, and the- con- 

 tinuation of the journey without any distinct napping whatever. They thus 

 sailed in plain view, as long as I remained on the rocks, probably 30 minutes. 



Winter. — These hardy birds of Arctic seas seem quite at home 

 among the drifting ice and snowstorms, and it is not until their sum- 

 mer feeding grounds become permanently closed with winter ice, in 

 October, that they are forced southward to spend the winter months 

 in the Aleutian Islands, along the Alaska coast, and south to Puget 

 Sound, or even California. Here they associate freely with the other 

 common gulls on the coast or spend their time offshore. They are so 

 much more pelagic in their habits than other gulls that they seem 

 much less abundant than they really are. 



DISTRIBUTION. 



< Breeding range.— 'Coasts and islands of the North Pacific, Bering 

 Sea, and the adjacent Arctic Ocean. East to Cape Lisburne and other 

 suitable parts of the western Alaskan coast. South to Seldovia, 

 Alaska, the Shumagin, Aleutian, Commander, and Kurile Islands. 

 West along the coast of Kamchatka and northeastern Siberia to 

 the Koliutschin Islands. Occurs in summer, but has not been found 

 breeding on the coast of southern Alaska (Yakutat and Sitka) at 

 Point Barrow and on the Siberian coast from Koliutschin Islands 

 to Chaun Bay. 



Breeding grounds protected in the following national reservations 

 in Alaska : Aleutian Islands (as Kiska, Near Islands, Unga, Unimak 

 Pass) , Pribilofs, St. George Island. 



Winter range. — From southeastern Alaska (Sitka) and perhaps 

 from the Aleutians, south along the coast of British Columbia, 

 Washington, Oregon, and California to northern Lower California 

 (San Geronimo Island). On the Asiatic side south to the Kurile 

 Islands and Japan (Yezo and Tokyo). 



Spring migration. — A return from ocean wandering to its breed- 

 ing grounds. Early dates of arrival : Commander Islands, Bering 

 Island, April 1; Pribilof Islands, St. Paul, April 20; Alaska, St. 

 Michael, May 6, and Point Barrow, June 2. Late dates of departure : 

 Lower California, San Geronimo Island, March 17; California, 

 Point Pinos, April 25 ; Washington, Port Townsend, May 19 ; British 

 Columbia, May 24. 



Fall migration. — Mainly eastward and southward off the coasts, 

 beginning in July and reaching British Columbia in September. 

 Average date of arrival at Point Pinos is November 14, earliest 

 November 5. Late dates of departure : Alaska, Point Barrow, 

 August 31, and St. Michael about October 15; Pribilof Islands, St. 

 Paul, October 12 ; Siberia, Koliutschin Island, September 22. 



