the shack of a fisherman and many times when our host had 

 cleaned his fish we threw the offal on some bare rocks. Per- 

 haps there was not a gull in sight; after a few minutes one 

 or two would come sailing from the distance, they would cir- 

 cle over their find and settle down to feed. Within fifteen 

 minutes the rock would be white with gulls, all screaming and 

 quarrelling and greedily devouring every bit of food. The 

 gulls act as a kind of sanitary police of the Great Lakes; 

 they devour all kinds of garbage offal and thus prevent any 

 fouling of the water. 



I have often wondered how it is that- water-birds do not 

 seem to suffer from exposing their feet to the cold water. 

 The waters of Lake Superior never rise much above 45 de- 

 grees but every observer has seen gulls floating for hours on 

 this cold water at a time, and on the still colder ice they seem 

 just as comfortable. The fact is that the feet of aquatic birds 

 always feel cold to the human touch, perhaps their feet have 

 remained reptilian while their bodies have acquired a much 

 higher temperature; even higher than that of man or mam- 

 mals. 



A very recent bird city is the cormorant settlement of Cor- 

 morant Island in Devils Lake, N. D. About thirty years ago 

 when the lake was surveyed the island did not exist. About 

 ten years ago after the lake had been steadily falling the 

 island appeared as a small ridge of glacial boulders. Very 

 soon afterwards some cormorants discovered the new island 

 and now there are about a hundred nests on the island and 

 in July after many of the young are grown the white rocks 

 are often covered with five hundred coal-black birds. Cor- 

 morants are fishermen who catch their prey by diving for 

 it in fairly deep water. The only creatures on which they 

 had been feeding when I visited their colony was a small 

 stickleback and the young of an odd amphilbian, known to 

 naturalists as mud-puppy. These seem to -be the only crea- 

 tures that have survived since the waters of Devils Lake have 

 become more and more alkaline. The cormorants arrive on 

 the lake as soon as the waters are free from ice and they 

 go South with the migrating hosts of wild ducks and geese. 



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