BIRDS OF ESSEX COUNTY. 83 



7 [27] Cepphus grylle (Linn). 

 Black Guillemot; "Sea Pigeon." 



Common winter visitor ; September to April 19. 



This bird is to be found off rocky shores, as at Rockport on the end of 

 Cape Ann and less frequently off Nahant. It is a shy bird and difficult to 

 approach. It is generally seen singly or two or three together. While swim- 

 ming, the Sea Pigeon nervously ducks its head at frequent intervals, appearing to 

 be dabbing at the water. It goes under water with a flop, both wings partly 

 spread so as to be ready for the first stroke, for, like all the Alcidce and unlike 

 the Grebes, it actually flies through the water, using its wings for propulsion. 

 The small dark tail bobs up as the bird disappears, and on rear view its red 

 feet may sometimes be seen. Its aerial flight is very direct, generally close 

 to the water, and its short pointed bill, and especially the white of the wing, 

 are very conspicuous. It generally sways slightly from side to side in 

 flight. Just before alighting it often circles about, glides, flaps its wings 

 quickly, and suddenly settles on the water. I have seen two chasing each 

 other off Rockport in January making the water foam. Occasionally one would 

 dodge the other by diving under water, reappearing quickly a few yards off. I 

 once saw two squatting side by side on a partly submerged timber floating in the 

 sea, and my companion mistook them for wooden decoys. 



The only sound I have heard the bird utter is a hissing or whistling sound 

 when suddenly alarmed. 



The Black Guillemot is in the white or mottled white plumage during most 

 of its stay on the Essex County coast, and for that reason may escape notice on 

 a sea covered with white-caps. In April, birds may be found that still retain 

 most of the whiteness of winter, while others have nearly completed their spring 

 moult. There is a specimen in the Peabody Academy at Salem, collected April 

 6th, 1 89 1, at Marblehead, which is in full black summer plumage. In this plum- 

 age it is easily recognized as it is totally black and has a large white wing patch 

 which is plainly visible when the bird is swimming as well as when it is flying. 

 This wing patch is also noticeable in the winter plumage as the rest of the wing 

 even then is dark. Its small size, short neck, and pointed bill distinguish it in 

 any plumage. I have seen its red legs both as it flew and just as it dove. The 

 other white sea bird in winter with which it might be confused is the Old Squaw, 

 but the larger size, longer neck, and the head markings of the latter bird distin- 

 guish it. 



