CANVASBACK 151 



of flosetl wing gray, with minute white dots or veimiculations; flight feathers 

 slaty brown; spei-ulum pale bluish gray bordered behind by a bar of white, 

 and uppermost two or three feathers narrowly edged with black; axillars 

 white; lining of wing pale gray; sides, flanks and belly like back but more 

 nearly white; under surface otherwise pure white or with faint suggestion of 

 dusky vermiculation; under tail coverts blackish; feet "greyish-blue" tinged 

 with "yellow" (Audubon, 1843, VI, p. 309). Total length (both sexes): 

 "20.00-23.50" inches (507-596 mm.) (Eidgway, 1900, p. 102). Males: Folded 

 wing 8.98-9.50 (228-241); bill along culmen 2.36-2.47 (59.9-62.7); tarsus 1.70- 

 1.81 (43.2-46.1) (four specimens from California). Adult female: Head, neck 

 and breast dull reddish brown, darker on top of head, and lighter, almost 

 white, on chin and throat; an indistinct whitish spot behind eye; back and 

 scapulars slaty brown, with traces of white vermiculations; rump blackish; 

 upper tail coverts and tail dusky brown; outer surface of closed wing uniform 

 slate gray without vermiculations; flight feathers, speculum and under surface 

 of w^ing as in male; whole under surface of body dull white, mottled with 

 grayish brown; sides with meagre white and dusky vermiculations. Folded 

 wing 8.50 (216); bill along culmen 2.36 (59.9); tarsus 1.64 (41.6) (one speci- 

 men from California). Juvenile plumage: Like that of adult female. Natal 

 plumage: Top of head, stripe down hind neck, and most of back, greenish 

 brown; side of head deep straw yellow, washed with dusky; paired spots on back 

 at base of tail, behind wing, and on hinder margin of wing, bright straw 

 yellow; whole lower surface deep yellow. 



Marks for field identification — Large size, reddish brown head and neck, 

 canvas-colored back and low forehead sloping down to long slender bill (see 

 pi. 5 and figs. 20 and 21). Distinguished from Eedhead by larger size, espe- 

 cially of head, blackish coloration around base of bill, red iris, and sloping 

 forehead and bill (which meet without evident angle between the two). 



Voice — Of male: "a peeping or growling note." Of females: a lou<l quack 

 and, when startled, a screaming curr-row (Eaton, 1910, p. 205). 



Xest — In a clump of reeds or tules in a shallow pond or slough but gen- 

 erally near a larger body of water; a large structure of reeds or tules well 

 lined with gray down (Bent, 1902, pp. 11-12). 



Eggs — 6 to 10, ovate to elliptical ovate in shape, measuring in inches 2.36 to 

 2.57 by 1.68 to 1.80 (in millimeters, 59.9 to 65.3 by 42.6 to 45.7), and averaging 

 2.48 by 1.75 (62.8 by 44.4) ; color rich grayish olive or greenish drab (Bent, 

 loe. cit.). 



General distribution — North America. Breeds from central British Columbia, 

 Fort Yukon, Great Slave Lake and southwestern Keewatin south to Oregon, 

 northern Nevada, Colorado (rarely), Nebraska and southern Minnesota; 

 winters from southern British Columbia, Nevada, Colorado, Illinois, Pennsyl- 

 vania and western New York, south to central Mexico and the Gulf coast (A. 

 O. U. Check-list, 1910, p. 74). 



Distribution in California — Common winter visitant (October to March) 

 both interiorly and along the seacoast. Most numerous about salt water bays 

 and coastal sloughs and marshes, seeming to prefer the deeper waters to the 

 muddy margins. The marshes about San Francisco and San Pablo bays con- 

 stitute a feeding ground for great numbers of this species. No definite breed- 

 ing records are known for California. 



The Canvasback, the far-famed "Can'' of the hunter, is probably 

 the best known of all American ducks, not excepting even the Mallard. 



