Lake Maxinkuckee, Physical and Biological Survey 527 



food becomes more and more scarce they eat other parts of 

 Vallisneria, and other plants which at first they reject. In fact, 

 when occasion requires, the Coots seem to be able to eat almost 

 any aquatic plant, and various kinds of animal food such as snails, 

 small crustaceans, and the like. There is no evidence that they 

 eat fish. Most of the stomachs examined in the fall contained 

 Chara, some contained bits of fine-leaved Potamogeton (probably 

 P. pectinatus) , also Ceratophyllum and Naias. Several stomachs 

 examined October 12, 1906, contained a quantity of finely com- 

 minuted light green material, probably leaves of Vallisneria. One 

 examined April 7 contained some vegetable fibers and leaves of 

 Potamogeton lucens mixed with white sand. Sixteen were exam- 

 ined September 9, and Naias was found to constitute the bulk of 

 the food. Two contained bits of Potamogeton and Ceratophyllum, 

 two had some small seeds like clover mixed with some fine gravel. 

 One examined November 4 contained fine fiits of Naias and a few 

 small shells of Vivipara contectoides. 



On January 3, 1901, the lake was frozen over excepting one 

 open pool near the Weedpatch, in which were several coots along 

 with a number of various species of ducks. At this time food was 

 particularly hard to get and the birds were disposed to rob one 

 another. Generally when one dived the others 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 rob each other but the ducks also robbed the 

 coots. Whenever a Coot came up with an unusually great amount 

 of food, the little bluebills and even the canvasback drake would 

 be on hand ready to help themselves. In this way the coots fed 

 not only each other but various ducks as well. It was observed 

 that the ducks did very little robbing of each other. Usually a con- 

 siderable mass of vegetcition was brought up each time. In this 

 particular place the principal food seemed to be one or more species 

 of Potamogeton, P. pectinatus predominating. The birds often 

 came up with long stems hanging over their backs. Quite often 

 the plant brought up looked like Chara, but of this we were not 

 sure. It is certain the plants they were getting here were not 

 their favorite food, but such as they could utilize when necessary 

 when better food was not to be had. 



Following is a tabular statement of the food found in a num- 

 ber of coots examined. 



3417618 



