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BIRDS OF NEW MEXICO 
Nest. —Usually in hollow trees or stumps, but sometimes on the ground, or in 
holes under bowlders, lined with twigs, moss, leaves, grasses, and light grayish 
white breast down, usually mixed with white breast feathers. Eggs: 6 to 17 
creamy buff. 
Food. —Small fish (many predatory), eels, aquatic salamanders, frogs, craw¬ 
fish, snails, bivalves, and leeches; caddice-fly larvae and winged ants; and occasion¬ 
ally seeds, stems, and roots of aquatic vegetation. 
General Habits. —The descriptive names of Buff-breasted Shel¬ 
drake for the drake and Dun-diver or Morocco-head for the duck seem 
to belong to this species; but the name Saw-bill is also applied to the 
Red-breasted and Hooded Mergansers. Goosander and Sheldrake are 
also common names for the American. As Mr. Henshaw says, “the 
narrow, serrated bill of the Goosander as contrasted with the broad, 
smooth bills of most ducks would suggest to the merest tyro that its 
habits must differ widely from those of most of its kin,” and he adds that 
its bill “with its saw-like teeth, is especially adapted to seizing and hold¬ 
ing slippery prey of various kinds.” Its long narrow body, as he also 
notes, “eminently fits it for swift progress under water where it spends 
much of its time” (1918, p. 108). It is, too, so well clad that it may 
winter wherever open water and food are found. 
On the bird reservation at Carlsbad in January, 1917, Mr. Willett 
estimated that there were about a thousand American and Red-breasted 
Mergansers, the American being the more abundant of the two. They 
were plentiful all winter, the Hooded occurring also but in smaller 
numbers. Gadwall, Mallards, Shovellers, and Pintails were also plenti¬ 
ful, Green-winged Teal abundant, the Blue-winged less so, Redheads and 
Golden-eyes occasionally seen. 
In Alaska Mr. Swarth saw the American Mergansers swimming 
slowly with neck outstretched and bill held at the surface of the water, 
filtering their food as the Shoveller does. He also noted a peculiar 
habit which made them conspicuous during th summer; individuals 
rising high in the air and circling around for h urs at a time, making at 
frequent and regular intervals “a most unmclodious squawk,” dis¬ 
tinguishable from the “coarse masculine quack” of the duck. Several 
times an old Merganser was seen “floating gently down a stream, with 
may be half a dozen downy young surrounding her, and with three or 
four perched on her back” (1911a, pp. 39-40). 
Additional Literature.—Bent, A. C., U. S. Nat. Mus. Bull. 126, 1-13, 1923. 
RED-BREASTED MERGANSER: Mergus serrator Linnaeus 
Description. — Length: About 20-25 inches, wing 8.6-9, bill about 2.5, tarsus 
1.8-1.9. Bill long, narrow, serrate, nostrils near base. Adult male in winter and 
breeding plumage: Head with double-pointed occipital crest black, glossed with 
green; neck with white collar ; forepart of back black, middle and hinder part gray 
waved with white and dusky; tail gray; surface of closed wing mostly white, crossed 
