THE OSPREY. 63 



very busy diving ami feeding. Tlie ducks were not so suitivo. It was lioth 

 amusing and instructive to watch them. Tlioy were not usually more than 

 eight to twelve feet from me, and 1 could plainly see the eyes of every one of 

 them, and the little bluebill came so close I could see the pupil of his eye. 

 I could see them close and open their eyes, which every one did frequently. 

 The little bluebill was a very active and persistent diver, lie seemed to be feed- 

 ing upon shells, as he never brought up anything bulky and he would do a lot of 

 vigorous chewing, and I could hear a crunching noise like shells being broken 

 up when he .chewed. The coots came so near I could see the black spots on 

 their bills and their red eyes. 



"While lying at this pool, several other ducks, chiefly mallartls and 

 whistlers, came and either alighted in the pool or circled about and left. The 

 whistlers dived very often, easily and rapidly, while the canvas-backs dived 

 but rarely and very clumsily at that. One or more of the coots were down 

 nearly all the time. They go down with a vim. Generally, when one dived, 

 the other three stayed up and watched for his coming up. They were able to 

 see him some moments before he reappeared and, hurrying to the spot where 

 they thought he would emerge, would be on hand ready to appropriate for 

 themselves as much of the food brought up as they could get possession of. 

 Not only would the coots thus rob each other, but the ducks also robbed 

 them. Whenever a coot came up with an unusually great load, the little blue- 

 bills and even the canvas-back drake would be on hand to help themselves. In 

 this way the coots feed not only each other but various ducks as well; but it 

 was observed that the ducks do very little robbing from each' other". 



Food: Usually a considerable mass of vegetation was brought up each 

 time. In this particular place the principal food seemed to be one or more 

 species of Potamogeton, P. pectinatus probably predominating. They often 

 come up with the long stems hanging over their backs. Quite often the plant 

 brought up looks like Chara, but of this I could not be sure. 



It is quite certain the plants they were getting here were not their favorite 

 food, but such as they could utilize when necessary. 



Depth: Soundings taken in this pool show that the depth was nine to 

 twelve feet. This open pool was not in the part of the lake which one would 

 expect to remain open longest, and Mr. Clark suggests the coots and ducks 

 determine the location of the open pools. As the ice-sheet spreads out more 

 and more from shore, it travels very rapidly, once the water has become 

 thoroughly chilled and the air cold and still. A number of birds feeding in 

 any particular place, or merely resting on the water, would keep the water 

 more or less disturbed, and the heat of their bodies would certainly raise the 

 temperature of the water slightly, at least, and freezing at this place would 



