LIFE HISTORIES OF NORTH AMERICAN" WILD FOWL. 211 



the chest. By February the head is practically adult, and the 

 remainder of the plumage closely resembles that of the adult, before 

 summer. Young birds of both sexes do not breed the first spring 

 but remain in flocks by themselves completing the molt. 



A complete molt of both old and young birds occurs in summer, 

 but it produces only a partial eclipse plumage, and after this molt 

 young birds become practically indistinguishable from adults, al- 

 though the full perfection of plumage is not acquired until a year 

 later. Mr. Millais (1913) says of the eclipse plumage: 



The adult male is somewhat late in assuming its eclipse dress, and seems to 

 require to be in good health to attain it, for both pochards and scaup which I have 

 kept in confinement have not fully changed as the wild birds do. About the middle 

 or end of July the adult male passes into a fairly complete eclipse. The whole of 

 the wings, scapulars, back, rump, tail and chest are at once molted direct to the 

 winter dress, a feature of the chest feathers being a broad band of white on the edge 

 of every feather. But an intermediate or temporary plumage for July, August, and 

 September is furnished in a large number of eclipse feathers for parts of the head, 

 neck, mantle, and flanks. The head becomes a dull brownish black, showing light 

 gray on the cheeks (due to the old winter feathers reaching the extremity of tJieir 

 length) . A few white feathers come into the lores (showing a distinct affinity to female 

 plumage), the neck assumes a gray collar, and the nape and mantle, instead of being 

 black, are filled with new gray and black vermiculated feathers similar to those on 

 the back. The flanks instead of being white as in spring and winter, are now filled 

 with white feathers finely vermiculated with brown . All of these new eclipse feathers 

 are again molted gradually. From the end of September, when the bird is still in 

 eclipse dress, till the end of October new winter feathers are constantly coming in and 

 displacing the old ones; and the full winter plumage is not assumed until November. 



Dr. Arthur A. Allen tells me that in both of the scaup ducks 

 molting begins about mid-August and the birds are in full eclipse by 

 mid-September. Breeding plumage begins to show again in mid- 

 October, but the full plumage may not be attained until the following 

 April, though some birds, probably the oldest, are practically in full 

 plumage by December 1st. 



Food. — The feeding grounds of the scaup duck are mainly in fairly 

 deep water at a safe distance from the shore where their food is 

 obtained by diving; they are expert at this and can remain under 

 water for 50 or 60 seconds. Where food is plentiful they often feed 

 in large companies, diving separately, indiscriminately, or all in 

 unison ; they show no particular system in their manner of diving 

 and are not very careful about posting sentinels to watch for dangers; 

 sometimes the whole flock will be below the surface at the same time, 

 so that an approach is fairly easy. In their summer homes in fresh- 

 water lakes and ponds they more often feed on or near the surface, 

 where they live on fish fry, tadpoles, small fishes, small snails and 

 other moUusks, flies, and water insects; they also eat some vegetable 

 food, such as the buds, stems, roots, and seeds of floating and sub- 

 merged water plants. Dr. F. Henry Yorke (1899) has identified 



