LIFE HISTORIES OF NORTH AMEBIOAN DIVING BIRDS. 23 



as far south as South Carolina and they are not uncommon on the 

 Massachusetts coast; but even here most of the birds migrate north 

 before the molt is complete. The complete postnuptial molt occurs in 

 the later summer and early fall, but is often not completed before 

 October or later. 



Food. — One of the horned grebe's favorite articles of food is small 

 fish, which it is quite expert at chasing and catching, as it darts about 

 swiftly and skillfully under water, catching them unawares and pur- 

 suing them at full speed. While living on the coast in winter it feeds 

 on shrimps, minute crustaceans, and salt water minnows. On inland 

 waters it eats a large proportion of animal food, such as small frogs, 

 tadpoles, aquatic lizards, leeches, beetles, and other insects. It also 

 feeds to some extent on grasses and other vegetable matter. Audubon 

 (1840) speaks of having found large quantities of grass seeds in the 

 stomach of this grebe. Mr. W. L. McAtee (1912) has made an ex- 

 haustive report on the food of this species, as follows : 



The most remarkable point about the food habits of grebes is that the stom- 

 achs almost invariably contain a considerable mass of feathers. Feathers are 

 fed to the young, and there is no question that they play some essential though 

 unknown part in the digestive economy. As they are finely ground in the giz- 

 zards it Is probable that finally they are digested and the available nutriment 

 assimilated. Feathers constituted practically 66 per cent of the contents of the 

 57 horned grebe stomachs examined. However, it is not likely that they furnish 

 a very large percentage of the nourishment needed by the birds. ■ As the nutri- 

 tive value of the feathers is unknovrn, this part of the stomach contents is ig- 

 nored. The other items of food are assigned 100 per cent, and the percentages 

 are given on that basis. Various beetles, chiefly aquatic, compose 23.3 per cent 

 of the food ; other insects (including aquatic bugs, caddis and chironomid larvae,' 

 dragon-fly nymphs, etc.), nearly 12 per cent; fishes, 27.8 per cent; crawfish. 

 20.7 per cent ; and other Crustacea, 13.8 per cent. A little other animal matter 

 is taken, including snails and spiders, and a small quantity of vegetable food 

 was found in two stomachs. 



Behavior. — The flight of the horned grebe is strong, direct, and 

 well-sustained; it looks, when on the wing, much like a miniature 

 loon. Its neck and its legs are stretched out to their full extent, fore 

 and aft, and its wings vibrate very rapidly. In winter it is difficult 

 to distinguish from the eared grebe, but it can be easily distinguished 

 from the pied-billed grebe by the absence of brown in its plumage 

 and by its white secondaries, which are very conspicuous in flight. 

 Its wings are small in proportion to its weight, so that it experiences 

 some difficulty, in rising from the water or from the ground ; in rising 

 it has to run along the surface for a long distance, beating the water 

 with both wings and feet; but, when well under way, it attains very 

 good speed. When migrating it usually travels singly or in small 

 scattered flocks. Along the New England coast we frequently see 

 horned grebes migrating, with the scoters in October, a mile or two 

 offshore; often several are in sight at one time, but I have never seen 



