250 BIRDS IN THEIR RELATIONS TO MAN. 



and even a few grasshoppers. They catch their food when 

 they cannot steal' it. The four that visit us are the skua gull, 

 the pomarine, parasitic, and long-tailed jaegers. None of 

 them are common. 



THE PETRELS AND AUKS. 



The Petrels, including fulmars and shearwaters, are pelagic 

 birds, adapted for both flying and swimming, that rarely land 

 except to lay their eggs. They will follow a ship for days 

 together, picking up such bits of food as may be thrown over- 

 board. The stomachs of several specimens of Wilson's petrel, 

 opened by the naturalist for whom they were named, showed 

 barnacles, seeds of gulf- weed, and greasy refuse from vessels. 

 Leach's petrel, a common species off the New England coast 

 and northward, attends fishing-vessels for the sake of the 

 waste from the cleaning tables. Fulmars accompany whalers 

 and feast upon scraps of blubber. All petrels are especially 

 fond of fatty matter. 



The Auks are an exclusively marine family of diving birds 

 that feed wholly on animal substances, such as small fish, 

 shrimps, roe, and crustaceans. The puffins, which constitute 

 one branch of this family, exhibit strange nuptial changes in 

 their bills. As the breeding season advances, the bill increases 

 in a vertical direction until it is nearly as deep as the head 

 itself. This increase is caused by the growth of additional 

 flakes, which are shed with the feathers during the moulting 

 season. 



The Common Puffin, or Sea Parrot, is the only one to visit 

 our eastern coast. Other auks have seasonal changes of bill, 

 but none of them belong on the Atlantic coast. The Great 

 Auk, which has been extinct for more than fifty years, was 

 formerly killed in great numbers for its flesh and feathers. 

 Its wings were so small that flight was out of the question, 

 and, though able to take pretty good care of itself in the water, 

 when on land it was at the mercy of any foe larger and more 



