Mergus merganser americanus Cassin
Other Names.—Shelldrake; Goosander; Fish Duck; Sawbill; American Merganser.
Description.—One of the largest of the ducks; bill long and narrow, with teeth on both mandibles. Adult male: Head and upper neck greenish black; lower neck, patches in wings, and underparts white; belly suffused with salmon-pink, noticeable in some individuals; back, shoulders, and wings black; rump and tail gray; bill and feet red; eyes bright red. Adult female: Head, with two large crests, and neck rich brown, marked with white areas in front of eye and on chin and upper throat; upperparts ashy gray; patch in wings, and breast and belly white. Length: 25 inches.
Range in Pennsylvania.—A fairly common and regular migrant along the larger waterways and sometimes on the smaller streams from about March 15 to April 20 and from October 1 to December 1. It frequently occurs in winter when the water is free of ice.
The mergansers are all expert fishermen and like to fish in swift water. They dive easily and their serrate bills help them to hold their slippery prey.
The female Merganser is difficult to distinguish from the female Red-breasted Merganser; in the present species, however, the white area on the chin and upper throat is sharply defined, whereas in the Red-breasted species the chin and throat are not white, but of a brownish color, paler than the rest of the head.