FAUNA OF THE ALEUTIAN ISLANDS AND ALASKA PENINSULA 167 



amidst the rank growth of Elymus. The most important require- 

 ments seem to be a handy source of food, and protection from 

 mammalian intrusion. As in the case of many other birds, if blue 

 foxes inhabit an island, the gulls nest on offshore rocks. 



Size of colonies varies from a few individuals to as many as 

 5,000 birds — this is an estimated count of birds that I observed 

 nesting on Glen Island, at the entrance to Izembek Bay in 1925. 

 A colony on a high green slope above the cliffs on Amak Island 

 numbered about 2,000, and, on Amagat Island, there were at least 

 2,000. Throughout the Aleutian chain to the westward, however, 

 the colonies numbered from 50 to 150, rarely more than 400. 

 The large numbers in the colonies (mentioned above) may be 

 due to the large food supply provided by the refuse at the cannery 

 at False Pass, the salmon fragments left by brown bears on the 

 Alaska Peninsula, and the fish that the gulls are able to obtain in 

 the salmon-filled streams. 



Nests are usually the typical gull structure — a mass of vegeta- 

 tion consisting of grasses, dry kelp or eel grass rolled up by the 

 tide, with dry sponges and other debris mixed in. Frequently, 

 however, the nest is a depression with a scanty lining of grass 

 or other material, and in some instances the gulls had merely 

 formed a depression in a windrow of kelp and eel grass above the 

 usual high-tide mark. 



The eggs are of the well-known large gull type, but considerable 

 variation was found. The color tone (speaking in general terms) 

 varied from brownish to greenish. One unusual set of two eggs 

 were a plain light-blue color without brown markings. 



Curiously enough, a corresponding variation in color was noted 

 also among the downy young. The majority had a buffy color 

 tone, but a few were blue gray with no buffy color. 



The downy young gull is precocious and is wonderfully adept 

 at hiding at an early age, and therefore it is hard to find where 

 vegetation is rank. On open sandy nesting grounds, the young 

 are likely to run, and they take to the water fearlessly, swimming 

 out a considerable distance. When once started in flight over 

 open ground, these youngsters go headlong and do not stop until 

 they think a safe distance has been attained, even though pursuit 

 has stopped. 



One young bird, with its gullet bulging with food, presented 

 an ungainly and ludicrous sight running across the beach. It 

 stopped to spew up food several times until its throat had re- 

 gained its normal proportions, then it took flight. This action 

 was observed repeatedly. Was the bird consciously lightening its 



