GULLS 



(39) Pagophila alba 



{Gunn.) (Gr., ice-loving; Lat., white). 



IVORY GULL; SNOW GULL. 

 Ad. — Plumage entirely pure white; 

 shafts of primaries straw color. Bill 

 yellow. Feet black. Iris brown. 

 Im. — Upper parts spotted with 

 gray; tips of primaries and tail 

 feathers with dusky spots. Plum- 

 age otherwise Hke that of the adults. 

 L., 17.50; W., 13.2s; T., 5.50; Tar., 

 1.4s; B., 1.40. Nest — Of grasses, 

 seaweed and feathers; on ledges 

 of sea-cliffs or on low ground; three 

 grayish-buff eggs, spotted with brown 

 and black, 2.30 x 1.70. 



Range — Arctic seas, breeding from 

 Melville Island and Baffin Land to 

 northern Greenland. Winters cas- 

 ually south to Long Island, Ontario, 

 and B. C. 



home is within the Arctic Circle, where they nest on the 

 ground in the moss-covered tundras. 



Family LARIDtE. Gulls and Terns 



The sub-family LARIN^, Gulls, is a large group of 

 chiefly maritime swimmers, whose plumage is largely white. 

 The bills of most species are large and slightly hooked, 

 usually yellow in adults. The tails are usually square- 

 ended. 



Gulls are fine swimmers, but do not dive; they get their 

 food from the surface of the water or from the ground. 

 Nearly all are, to a certain extent, carnivorous, for they 

 devour the eggs and young of other smaller sea-birds. 

 Their flight is strong and graceful, but not fast, the head and 

 bill normally being carried in horizontal positions. The 

 plumages of the adults, year olds and young vary greatly. 

 The character of markings on the outer primaries is fairly 

 stable and often serves to distinguish species. The colored 



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