Mergus merganser, Linn. Syst. Nat. i. p. 208 (1766) ; Naum. xii. p. 358, Taf. 326 ; Hewitson, ii. p. 439, pl. cxviii. fig. 3. ; Gould, v. pl. 384 ; Dresser, vi. p. 685, pl. 452 ; David and Oust. Ois. Chine, p. 510 ; Saunders, p. 471 ; Lilford, vii. p. 137, pl. 58 ; Tacz. F. O. Sib. O. p. 1203 : M. castor, Linn. Syst. Nat. i. p. 209 (1766) ; Gould, B. of Gt. Brit. v. pl. 34 ; (Salvadori), Cat. B, Br. Mus. xxvii. p. 472 ; (Blanf.), F. Brit. Ind. Birds, iv. p. 469 ; M. comatus (Salv.), tom. cit. p. 475 (1895).
Grand Earle, French ; Smergo maggiore, Ital. ; Grosser Sager, German ; Groote Zaagbek, Dutch ; Stor Skallesluger, Dan. ; Korfagel, Norweg. ; Storskrake, Swed. ; Kussa-koalsi, Lapp. ; Iso-koskelo, Uu-koskelo, Finn. ; Bolshoy-Krahal, Russ. ; Gulond, Icel. ; Kawa-aisa, Jap.
Male ad. (Archangel). Head and upper neck glossed with green, the occipital feathers elongated ; lower neck and upper back white, the latter marked with black, becoming with the outer webs of scapulars glossy black ; lower back, rump, upper tail-coverts, and tail dark ashy, the last darkest ; primaries ashy black ; secondaries white margined with black, the innermost black ; primary coverts, edge and base of wing blackish grey ; rest of wing-coverts and under parts white, the breast and abdomen tinged with warm reddish buff ; bill deep vermilion, the ridge of upper mandible and tooth blackish ; legs vermilion ; iris deep reddish brown. Culmen 2.4, wing 11.0, tail 5.0, tarsus 1.9 inch. The female has the crown, nape, and upper neck rusty red, the lores and round the eye dark brown ; upper parts brown, greyish on the back ; chin, lower neck, and under parts white, the flanks marked with pale slate-grey ; wings as in the male.
Hab. High north of Europe and Asia in the breeding season, in winter visiting Britain, Central and Southern Europe to the Mediterranean ; Central Asia east to Japan and Mongolia ; China and India in winter. The American form, M. americanus, Cass, differs very slightly in having a black bar across the wings at the base of the greater coverts.
Frequents fresh water during the breeding season, being found on the sea-coast only in the winter. Its cry is loud and harsh, chiefly uttered when the bird is on the wing. It feeds principally on fish, but also eats water-insects and larvae. It usually nests in a hollow tree, and readily takes to a nest-box, but sometimes on the ground under a stone, the nest being well lined with down, and late in April or early in May deposits 8 to 12 eggs, which are warm yellowish white, smooth in texture, and measure about 2.65 by 1.81.
878. Mergus merganser