32 BULLETIlSr 107, Ul^^ITED STATES NATIONAL MUSEUM. 



are while, becoming dusky on the sides and tinged with pinkish buff 

 on the breast and throat. The young birds are nearly fully grown 

 before the first winter plumage is acquired, which appears first on 

 the breast and last on the neck and rump. Young birds in the fall 

 look very much like the horned grebe in corresponding plumage, but 

 they are somewhat smaller, with smaller and slenderer heads and 

 necks, and the shape of the bills is different and characteristic of the 

 species. The first winter plumage of the eared grebe, dark above 

 and white below, is similar to the adult winter plumage, but the 

 black of the back is "browner and the colors of the head are duller 

 and less distinctly outlined ; the bill is also smaller and not so clearly 

 defined in shape. A first prenuptial molt takes place in April and 

 May, Avhich involves nearly all, if not all, the contour feathers and 

 produces a plumage closely resembling that of the adult. At the 

 first post-nuptial molt, the following summer, the plumage is com- 

 pletely rencAved and young birds become indistinguishable from 

 adults at an age of 14 and 15 months. 



Adults have two molts, a partial prenuptial molt, involving the 

 head and neck and, at least part, if not all of the body plumage, 

 which begins in December, and a complete post-nuptial molt in 

 August and September. Thus it will be seen that the winter plum- 

 age, or perhaps it should be called the fall plumage, is worn but 

 three or four months in the fall. Individuals vary greatly in the 

 times at which this plumage is acquired and replaced. Adults in the 

 fall have white throats, have less brown in the sides and have only 

 traces of the yellowish brown ear tufts; but they can be recognized 

 by the size and shape of the bills and by the darker backs and heads ; 

 many birds also have more or less black in the throats during the 

 fall. The prenuptial molt into the adult spring plumage is some- 

 times prolonged into May but is usually completed by May 1. 



Food. — The food of the eared grebe consists principally of water 

 insects and their larvae, beetles, tadpoles, very small frogs and 

 shrimps, all of which it obtains by diving ; it also feeds to some ex- 

 tent on various water plants; and feathers, presumably from its own 

 body are often found in its stomach. Dr. T. S. Eoberts (1900) says: 



The stomachs and gullets of several birds collected by the writer and kindly 

 examined by Professor Beal, of the Biological Survey at Washington, con- 

 tained a mass of insect debris to the exclusion of all else. One stomach alone 

 furnished some 15 different species, among them several varieties injurious to 

 the interests of man. The chief part of the food, however, during the time 

 of our visit to the colony, and that on which the young were largely fed, was 

 the nymphs of dragon flies which were then to be found in immense numbers 

 in the meadows near by. The writer counted no less than 327 of these insects 

 in a single stomach. 



Behavior. — The eared grebe is seldom seen in flight, except on 

 migrations, for the bird seems reluctant to leave the water and pre- 



