LIFE HISTORIES OF NORTH AMERICAN WILD FOWL 135 



one is created by the mixture of old, worn, faded feathers with 

 fresh, new ones. There is also no marked seasonal change in any of 

 the scoters. 



Food. — The food of the white-winged scoter includes a varied bill 

 of fare, differing greatly in the various localities which it visits. 

 On the New England coast, where it is so abundant in the winter, 

 it is strictly maritime and seems to feed mainly on small mussels and 

 other small mollusks which it obtains by diving about the submerged 

 ledges, often to a depth of 40 feet, tearing, with its powerful bill, 

 the shellfish from the rocks to which they are firmly attached. I 

 have seen the crojj of one of these birds crammed full of mussels 

 nearly an inch long, and have often wondered whether the tough 

 shells were ground up in their muscular stomachs or chemically dis- 

 solved ; probably both actions are necessary. Some of our fishermen 

 have claimed that scoters are injurious to the shellfish interests on 

 our coast, accusing them of feeding on young scallops and clams, 

 but I doubt if they do much damage in this way; they certainl}; 

 could not obtain many clams, which are usually buried in the sand. 

 Sea clams, which are sometimes found on the surface of a sand flat, 

 are probably more often taken by these birds. J. C. Cahoon (1889) 

 recorded an instance where the clam was too big for the scoter, which 

 was found floating on the water with a large sea clam firmly clasped 

 on its bill ; probably the weight of the clam had kept the bird's head 

 under water until it was drowned. On inland lakes and ponds they 

 live largely on crawfish, slugs, snails, and mussels. They have been 

 known to eat, according to Dr. F. Henry Yorke (1889), small fishes, 

 frogs, tadpoles, fish spawn, and the larvae of insects. On the western 

 sloughs and marshes they evidently feed largel}'^ on vegetable food, 

 such as flags, duckweed, pondweed, and pickerel weed. Doctor Yorke 

 reports the following families of plants as identified among their 

 foods: Lemnaceae, Naiadaceae, Selaginellaceae, Salviniaceae, Glati- 

 naceae, Gentianaceae, Lentibulariaceae, Pontederiaceae, and Maya- 

 ceae ; also the following genera : Iris, Myriophyllum, Callitriche, and 

 Utricularia. 



Behavior. — The flight of the white-winged scoter is heavy and 

 apparently labored ; it seems to experience considerable difficulty in 

 lifting its heavy body from the surface of the water; except when 

 facing a strong wind, it has to patter along the surface for some 

 distance, using its feet to gain momentum. But, when well under 

 way, it is much swifter than it seems, is strong, direct, and well 

 sustained. Migrating flocks, in all sorts of irregular formations, 

 fly high under favorable circumstances; but when flying against the 

 wind or in stormy weather (northeast storms seem to be particularly 

 favorable for the migration of the scoters) they fly close to the 



