LIFE HISTOEIES OF NORTH AMERICAN PETRET^S AND PELICANS. 239 



the first winter plumage the belly is nearly white. In this respect 

 they differ from double-crested cormorants, which have a light-gray 

 breast shading down to black on the lower belly. With good glasses 

 I have been able to distinguish the two species at the distance of a 

 mile. In the full adult plumage both sexes are alike, and are blue 

 black beloAv and bronzy slate-brown above. There is a broad band of 

 white on the throat below the bare gular sac, there are scattered 

 linear white feathers on the side of the head and upper neck, and 

 there are patches of white feathers on the flanks. These white 

 patches, but particularly the white feathers of the throat, are ex- 

 cellent field marks to distinguish this bird from the double-crested 

 cormorant. The fowlers of Belfast Lough, Ireland, according to 

 Patterson (1880) speak of the flank patch as " the watch that it carries 

 under the wing." The bill is grayish-black ; yellowish white on the 

 edges of both mandibles and at the base of the lower mandible. 

 The iris is a light bluish green with a dull olive bare space above and 

 a bright red space below. The gular sac is yellow, not orange as in 

 the double-crested species. The feet are grayish black. 



The distinctive white patches are worn by both sexes but for a 

 brief time during the nuptial season. Yarrell (1871) reports some 

 observations on this point on captive birds in the gardens of the 

 London Zoological Society; the white feathers on the side of the 

 head and neck began to appear January 4th, arrived at greatest per- 

 fection February 26th, began to disappear on April 2d, and were 

 gone by May 12th ; the white patches on the thighs began on January 

 24th, were complete in five weeks, began to disappear on June 16th 

 and were almost entirely gone on July 30th. It is probably that 

 three or four years are needed before the full adult plumage is at- 

 tained. 



Food. — The cormorant is an expert on the wing and in the water, 

 and its habits are very similar to those of its double-crested cousin. 

 Its food consists entirely of fish, which it is able to follow under 

 water with great speed and seize with its powerful hook-like bill. 

 When it appears on the surface it sometimes throws the fish up into 

 the air in order to get a better hold; its gullet is so wide that its 

 swallowing capacity is large. Most of the fish it captures are of no 

 economic importance to man, but in some cases, no doubt, a toll is 

 taken of useful fish. On Cape Cod I have seen cormorants perched 

 on the fencing of fish weirs, and it is probable that they are not 

 considered desirable visitors by the fishermen. With us the cormorant 

 is rarely seen away from the sea, although there are records from 

 Lake Ontario. Stead (1906) says of it in New Zealand that it " is 

 with us largely an inland bird, frequenting fresh-water lakes and 

 rivers." Yarrell (1871) writes that they follow the course of rivers 

 many miles inland. 



