[2.88] BIRDS OF OREGON 



DISTRIBUTION. General: Arctic Coast and islands west of Greenland, to Point 

 Barrow in migration, south in winter to coast of British Columbia and California. 

 In Oregon: Uncommon winter visitor known with certainty from a few specimens. 



ON DECEMBER 2.2., 1932., Gabrielson collected an adult female (Gabrielson 

 Coll. No. 2.098) on the Columbia River near Portland that proved to be 

 a Thayer's Gull. An immature bird (Gabrielson Coll. No. 2.196), taken 

 January T.^, 1933, near the same spot, was very puzzling. It matched 

 closely a single bird in Jewett's collection, taken at Netarts, August xo, 

 192.5, but we could not find similar birds in any of the collections avail- 

 able to us including those of the Biological Survey and the United States 

 National Museum. By process of elimination the birds were finally placed 

 as L. a. thayeri. Later they were sent to George Willett for comparison 

 with the fine series of northern gulls in the Bishop collection. He con- 

 firmed the identification, and today these are the only definite records for 

 this form from the State. Thayer's Gull cannot be distinguished in life 

 from the Herring Gull, and careful comparison with the skins in hand is 

 required to establish its identity. In habits and behavior it is like the 

 other species that make up the swarming hordes of gulls found on the 

 Oregon coast and the Columbia River during winter. 



California Gull: 



Larus californicus Lawrence 



DESCRIPTION. "Adults: Mantle clear bluish gray; outer primaries black, tipped with 

 white, the first two with subterminal white spots; a distinct gray wedge on inner 

 web of second; bill yellow, with red and black spot near end of lower mandible; feet 

 greenish. Young: upper parts coarsely spotted and mottled with dusky, buffy, 

 grayish, and whitish; under parts mottled and streaked; quills and tail blackish; bill 

 dusky, with black tip." (Bailey) Downy young: "The young bird when first 

 hatched, is covered with thick, soft down of plain, light colors to match its sur- 

 roundings, 'light buff' to 'cartridge buff,' brightest on the head and breast; the 

 upper parts and throat are clouded or variegated with light grayish, and the head 

 is sparingly spotted with dull black." (Bent) Si%e: "Length 2.0-2.3, wing 15.00- 

 16.75, bill 1.65-1.15, depth of bill at angle .60-. 75." (Bailey) Nest: Of usual gull 

 type, usually on ground, composed of weeds, grass, bits of sticks, feathers, and other 

 similar available material. Eggs: 2. or 3, similar to other gulls' eggs, ground color 

 varying shades of brown or buff, irregularly spotted and blotched with browns and 

 grays. 



DISTRIBUTION. General: Breeds from Great Slave Lake, Canada, and Stump and 

 Devils Lake, North Dakota, south to northern Utah and west to central British 

 Columbia and northeastern California. Winters on Pacific Coast from British Colum- 

 bia to Lower California. In Oregon: Breeds in Klamath (Spring and Upper Klamath 

 Lakes), Lake (Summer and, formerly, Silver Lakes), and Harney (Malheur Lake) 

 Counties. Winters largely on coast and sparingly on open water anywhere in State. 

 A few summer birds remain on coast but do not breed. 



THE BEAUTIFUL medium-sized California Gull (Plate 47, A) was first 

 noted by Newberry (1857), who found it at the mouth of the Columbia 

 in October 1855. It is now one of the most widely distributed and 



