Red-breasted Merganser 33 
nest is generally placed in a hollow tree, sometimes on 
the ground; it is constructed of moss and leaves and 
lined with down, plucked from the parents’ breast ; 
the eggs, usually ten, though as many as fourteen have 
been found, are oval and pale buffy to white in colour ; 
they measure 2°65 x 1°78. 
Red-breasted Merganser. Mergus serrator. 
A.O.U. Checklist no 129—Colorado Records—Ridgway 79, p. 234; 
Thorne 87, p. 264; Morrison 89, p. 148; Cooke 94, p. 183; 97, pp. 53, 
194; Henderson 03, p. 234; 09, p. 225; Cary 09, p. 180. 
Description.—Male—Head (with a long thin occipital crest) and upper- 
neck all round, black glossed with green; back black, becoming greyish 
on the rump and tail; wings chiefly white on the surface but the prim- 
aries black; below including the lower-neck all round, except for a 
dorsal dark line, white ; a patch of reddish-brown streaked with dusky 
on, the breast ; iris, bill and feet red. Length 24:0; wing 9:0; tail 4:0; 
culmen 2-20; tarsus 1°6. 
The female and young have the crown greyish-brown, becoming 
more rufous on the sides and neck ; rest of the upper-parts slaty, the 
white wing-patch much restricted ; below white; wing about 8:5. 
Both sexes can be easily distinguished from M. americanus by 
the position of the nostril, which is nearer the base of the bill instead 
of about the middle of its length. 
Distribution.—The northern parts of both hemispheres ; in America 
breeding from, Alaska and Greenland south to Minnesota and New 
Brunswick ; in winter south of these limits to California, the Gulf 
and Cuba. 
The Red-breasted Merganser is a somewhat rare bird in Colorado, 
but it occasionally winters at Barr, near Denver, and along the Platte 
River ; it is more common. on migration and has been, recorded from 
Fort Collins and Middle Park (Cooke), Boulder co. (Henderson) and 
Fort Lyon by Thorne, probably all on migration. Cary reports he 
saw a mounted specimen at La Veta which had been shot on a reservoir 
near by. Hersey informs me he has seen this species with “ flappers’ 
in July, on the Fraser Creek in Middle Park at about 7,500 feet, and 
he believes that it breeds there. 
Habits.—The Red-breasted does not differ very much 
from the American Merganser, except that the nest appears 
to be generally placed on the ground though sheltered 
D 
