178 THE GULLS 



kind, alive or dead, are freely eaten, and the lump fish, Cydopterus 

 lumpus, is especially sought for. Among Crustacea we may mention 

 Cancer pulex and C. araneus, and among Mollusca Venus islandica and 

 Pecten islandicus as forming part of its diet, as well as a large species 

 of Decapod (Hyas) and Holothurians. Hagerup states that in 

 spring, when the flocks of eiders are diving for mussels off the Green- 

 land coast, the glaucous-gulls may be observed swimming or flying 

 among them, and as soon as a duck comes to the surface with a 

 mussel, a gull attempts to seize it (Auk, 1889, p. 214). But this 

 is not all, for even when animal food is plentiful it likes to vary it 

 with seaweed. Saxby has taken as many as five species of Algse from 

 the stomach of one bird, chiefly Alaria esculenta, while Naumann says 

 that it is said to eat the berries of Empetrwm, nigrum. With such 

 varied tastes it is perhaps not surprising that Saxby found only one of 

 all that he examined to be in poor condition ; usually they were so fat 

 as to cause much trouble in skinning, and the fat always smelt strongly 

 of whale-oil. The more indigestible portions of the food are thrown 

 up again in the form of pellets, and Schalow gives some interesting 

 details of the contents of some of these obtained in Spitsbergen. 1 

 One huge pellet, nearly 8 inches long and 1 inch wide, contained the 

 remains of a young ivory-gull, which had been swallowed whole. 

 Another was globular-shaped, and measured about 2f inches long and 

 1| inch wide. As Schalow remarks, it seems inconceivable how a 

 pellet over 6 inches long and If inch wide can pass through the 

 gullet without injury to the bird. 



The notes of this species have a great resemblance to those of the 

 other large gulls, such as the great blackback. Le Hoi writes the 

 call-note as a loud "kau kau kawkawkaw," which is probably the same 

 sound which von Heuglin syllables as " gogdu, gogau" and Naumann as 

 "giiowutiu." When the breeding-place is invaded a shrill " gagagak" 

 or "gogogok" is incessantly uttered, probably the former being a 

 remonstrance by the hen and the latter by the cock bird. Other 



1 Journal filr Ornithologie, 1899, p. 378. 



