LIFE HISTORIES 01? NORTH AMERICAN GULLS AND TERNS. 103 



position. As the sex can not be distinguished one may only guess 

 that it is the males that are thus parading themselves. At this time 

 of year, more than at other times, they are frequently to be seen chas- 

 ing each other in the air, and that too without the object of stealing 

 coveted food morsels. Mr. Ralph Hoffman reports seeing a pair of 

 these birds bowing to each other at Ipswich beach just prior to the 

 act of mating. On the ground they sometimes seize each other by the 

 bills and strike with the wings and feet. H. L. Ward (1906) de- 

 scribes an action on the part of the gulls which suggested to him the 

 dance of the albatross at Laysan. He says : 



Two adults may be standing near together, when one will stop, hold its neck 

 nearly horizontal, its bill pointed down, wave its head in and out from its 

 body, and slightly up and down, in a rapid, jerky way, reminding one somewhat 

 of the motions of a duck feeding in shallow water, at the same time emitting 

 a peculiar chickenlike chatter. The other one immediately joins in, apparently 

 directing its attention to the same place in the ground, and the performance 

 is kept up for a minute or two, when the birds straighten up, perhaps to 

 repeat the operation two or three times with short intermissions. 



Nesting. — The herring gull breeds in small or large colonies, but 

 always in the neighborhood of some body of water — a river, lake, or 

 the sea. Single nests are rare, and usually point to the breaking 

 up and scattering of a colony, for the herring gull is a very social 

 creature and prefers to nest, feed, rest, and sleep in companies. 

 Mr. Brewster in 1881 found many of the herring gulls on the south- 

 ern coast of Labrador nesting in widely scattered regions, and says 

 (1883) "the policy of scattering over wide areas, however, probably 

 preserves the majority of nests from discovery." 



At the Duck Islands off the coast of Maine is a large breeding 

 colony which has been protected for some years. Previously the 

 colony was despoiled of eggs every year by fishermen, and many 

 of the birds had acquired the habit of nesting in trees, where they 

 were less likely to be robbed. Herring gulls have resorted to trees 

 as nesting sites when disturbed by man in places other than these 

 Duck Islands. Audubon (1840) in 1833 found the gulls nesting in 

 fir trees on Grand Manan Island. He was informed that the habit 

 had been acquired within the recollection of those living there, and 

 that previously they had nested on the ground. Dr. Henry Bryant 

 visited the same locality in 1856 and found that fewer were building 

 in trees than in Audubon's time — a fact he attributes to greater 

 freedom from persecution. Barrows (1912) says that he has never 

 known herring gulls to nest in trees in the Great Lakes region. 

 When I visited the Duck Island in 1904 the birds under protection 

 had returned with few exceptions to the normal habit of nesting on 

 the ground. ' '" 



174785—21 8 



