LIFE HISTORIES OF NORTH AMERICAN WILD FOWL 85 



a bubble. Like the oldsquaws, the eider mothers join their little flocks, and one 

 mother leads the file while the other brings up the rear. From the time they 

 are hatched until they leave for the South, they keep to the open sea, coming 

 in to the shore sometimes to rest, but more frequently resting on ice floes. 



While the young birds are developing in strength and ability to swim, the 

 mothers constantly lead them southward. From mid-August to mid-September 

 a constant procession of eiders swims outward from the bays and fjords and 

 goes on southward. The southward flight migration is late, beginning about 

 the 1st of September and continuing until the ice freezes, often in October. 

 Even so, many of the young birds are still unable to fly when the fjords freeze 

 over, and frequently flocks of them are caught by sudden freezes and im- 

 prisoned in little pools where they finally freeze to death or fall prey to the 

 foxes, bears, or Eskimo. 



Plumages. — The downy young of the three eiders, inollissima, 

 dresseri^ and V-nigra^ 'are all practically indistinguishable. The 

 upper parts are " olive brown," deepening to " clove brown " on the 

 crown and rump, and paling to " light drab " on the sides and to 

 " pale drab-gray " on the throat and belly ; there is a broad supercil- 

 iary stripe of " light drab " or dull " wood brown " above the eyes 

 and the cheeks, and lores are abruptly darker than their surround- 

 ings. Before the young bird is half grown the first dusky, brown- 

 tipped feathers of the juvenal plumage appear on the flanks and 

 scapulars; the tail feathers start next, then the breast plumage and 

 the head; the young bird is nearly fully grown before the last of 

 the down disappears from the upper back and rump ; the wings ap- 

 pear last of all, so that both old and young birds are flightless to- 

 gether in August. 



In the juvenal plumage the sexes are much alike; this plumage is 

 worn by the young male through the fall and resembles that of the 

 young female, but not that of the adult female. Sometimes as early 

 as October, but more often not until December, the young male 

 begins to differentiate by acquiring a few black feathers in the 

 flanks and scapulars and a few white feathers on the lower neck or 

 chest. These two colors increase in purity and extent by a prac- 

 tically continuous molt throughout the winter and spring, with 

 considerable individual variation. The tail is molted during the 

 winter, the time varying with different birds, and some white 

 feathers appear in the scapulars and rump, in early spring or before 

 that. By April many young males have the throat, neck, and chest 

 almost wholly white, the back almost wholly black and white, and 

 the head nearly all black above, but the wings and the under parts 

 are still wholly immature; at this stage, the sea-green patch over 

 and behind the ear coverts is often completely developed or inter- 

 mixed with black and brown feathers of the first stage. 



The next change takes place at the summer molt, in July and 

 August. This is a complete molt involving a double molt of much 



