LIFE HISTORIES OF NORTH AMERICAN PETRELS AND PELICANS. 169 



crustaceans from the surface of the water. When picked up wounded 

 or caught in their burrows the birds eject from their bill and nostrils 

 a yellow or reddish oily fluid with a strong musty odor. This odor 

 is very characteristic and clings to the skins of these birds in collec- 

 tions. Robert Hall (1900) says living birds when handled eject "a ■ 

 fatty globule for a distance of 2 feet." I have found this oily fluid 

 in their stomachs and on one or two occasions a few bits of charcoal, 

 on another a few small pebbles. 



As already shown the Wilson petrel spends its nonbreeding season, 

 its winter, in the northern summer. As the bird is very tame its 

 habits may be studied at close range on almost any cod-fishing expe- 

 dition a mile or more from the Atlantic seaboard of North America. 

 When sailing or steaming along the coast or even in mid-Atlantic one 

 rarely fails to see an occasional petrel flying close to the water beside 

 or ahead of the boat or a few gathering in the wake, ever on the alert 

 to pick up any morsel that may drop from the vessel. Day after day 

 we may watch these tireless birds from any transatlantic steamer, but 

 it is, of course, impossible to say how far the same birds follow the 

 boat. On one or two occasions at night I have seen a petrel start up 

 from near the bow of the vessel, wheel wildly over head and disap- 

 ])ear in the darkness astern. Occasionally they drop on the deck. 

 Whether the birds were asleep on the water or not is a matter of con- 

 jecture. 



When a boat stops to fish the scattered wide-ranging petrels are 

 at once attracted by the bait and " gurry" that are inseparable from 

 this pursuit, and gather sometimes in considerable numbers. If fish 

 are being cleaned, or if one purposely throws out bits of fish livers to 

 attract the birds the gathering is often a large one. A large piece 

 of liver may be seized upon by several birds until it is torn to pieces. 

 It is not often that these birds actually settle on the water, but they do 

 so at times and ride as lightly as phalaropes. As a rule the petrels pick 

 up the food as they skim over the water either bounding with both 

 feet together or pattering lightly over the water running or walking 

 with alternate feet. In both cases they keep their wings spread, and 

 support themselves largely on these. Both methods — feet together or 

 alternate — are extremely graceful and fascinating to watch ; in the 

 first case the birds appear as if on springs and bound lightly from 

 wave to wave. The wings are often held motionless and the birds ap- 

 pear to take advantage of the upcurrents of air deflected from the 

 waves. 



Behwvior. — The flight of the Wilson petrel is graceful and swallow- 

 like and the birds often winnow the air as if for insects. The stormier 

 the da}'' the more likely is one to see them close to the shore, but it is 

 rare that they are seen flying over it except in their nesting region. 



