30 



NORTH AMERICAN BIRDS EGGS. 



[Gray.] 



48. Slaty-backed Gull. Larus schistisagus. 

 Range. North Pacific and Arctic Oceans. 



This Gull, which is similar to the Great Black-backed, but is smaller 

 and has a lighter mantle, does not breed in any considerable numbers on the 



American side of the 

 _________ Pacific. It nests in 



' : ''""iii^~- June on some of the 



- ^~ ^ islands in Bering Sea 



and probably more 

 commonly farther 

 north. They often 

 nest in company with 

 other species, placing 

 their small mounds of 

 seaweed on the ground 

 on the higher parts of 

 the islands. The full 

 set contains three eggs 

 of grayish or brownish 

 color, spotted with dark 

 brown or black. Size 

 2.90 x 2. Data.-Har- 

 rowby Bay, N. W. T. 

 Canada, June 11, 1901. 

 Nest of grass, roots and 

 mud and lined with 

 dry grass ; on point 

 making into the bay. Collector, Capt. H. H. Bodfish. 



49. Western Gull. Larusoccidentalis. 



Range. Pacific Coast, breeding from southern California to British Columbia. 



This bird, which is the most southerly distributed of the larger Gulls 

 is twenty-four inches in length. Mantle slate colored ; primaries black, 

 both these and the secondaries being broadly tipped with white. 

 These Gulls nest abund- 

 antly on the Farallones, 

 the majority of them 

 showing a preference for 

 the lower portions of the 

 island, although they 

 nest on the ledges also. 

 Besides man, these Gulls 

 are the greatest enemies 

 that the Murres have to 

 contend against. They 

 are always on the watch 

 and if a Murre leaves its 

 nest, one of the Gulls is 

 nearly always ready to 

 pounce upon the egg and 

 carry it away bodily in 

 his bill. They also 

 devour a great many 

 young birds. The Gulls 

 too suffer when the eggers 

 come, for their eggs are 

 gathered up with the Murres for the markets. They make their nests of weeds 

 and grass, and during May and June lay three eggs showing the usual variations 

 of color common to the Gulls eggs. Size 2.75 x 1.90. Data. Farallone Is., Cal., 

 June 20, 1897. Nest a mass of Farallone weed on a ledge. 



[Pale greenish buff.] 



