34 BULLETIN 113, UNITED STATES NATIONAL MUSEUM. 



Behavior.— The flight of the ivory gull is said to be light and 

 graceful. Yarrell (1871) says "that its note is shrill and not un- 

 like that of the Arctic tern, and its flight is more like that of a tern 

 than of an ordinary gull." Nuttall (1834) writes: "Its. only note 

 consists of a loud and disagreeable scream." Selby (1833) says: 

 "Its voice is strong and harsh." Mr. A. L. : y.. Manniche. (1910) 

 says: "This pretty bird, with its short but sonorous note,,, would 

 make a wonderfully animating impression in these silent and deso- 

 late surroundings." 



Winter. — The migration amounts merely to a withdrawal from its 

 breeding grounds and such northern portions of its summer range 

 as are rendered uninhabitable by the closing in of ice and snow. The 

 species is merely forced southward by the advance' of winter condi- 

 tions and frequents the more or less open edge ; of t the ice pack all 

 winter. Mr. Clarke (1898) makes this statement: 



Dr. Neale records that in the autumn of 1881 the ivory gulls departed from 

 Gape Flora (Franz Josef Land) at the end of October, and arrived there the 

 following spring on the 20th of April. Pr. Nansen observed them for the first 

 time in 1896 as early as the 12th of March, at his winter quarters on Frederick 

 Jackson Island. 



On the Labrador coast it seems to occur in the late fall only. Mr. 

 Kumlien (1879) noted it as " very common " in Cumberland Sound 

 " just before it froze up, for a few days only." Doctor Townsend 

 (1907) writes: 



Dr. Mumford, Mr. Frank Lewis, and others at Battle Harbor told us of shoot- 

 ing " ice patridges," which came with-the ice and seals in November ! or Decem- 

 ber. They stay for about two weeks or a month and then depart,- not to be 

 seen again for a year. At times they are very abundant and even fly ; about the 

 houses. These birds are shot for food, and - are often obtained in the following 

 manner : About a gallon of seals' blood is poured on the ice near the rocks, and 

 as the birds hover about they are easily shot. Some of the birds in their eager- 

 ness to obtain the blood dash themselves with such force against the ice as to 

 kill themselves. 



A recent occurrence of the ivory gull in Portland Harbor, Maine, is 

 recorded by Mr. Arthur H. Norton (1918) ; he and Mr. Walter H. 

 Rich observed it at short range on January 5, 1918. He says : 



The snowy whiteness of its plumage was always noticeably different from any 

 other gull in the harbor, which contained at the time an abundance of Larus 

 argehtatus in all plumages, Larus kumlieni, and Larus leucopterus. Its habits 

 and flight also differed distinctly ; it was much more restless, now alighting on 

 the ice, either to remain at rest for a few minutes, or to feed at . the water's 

 edge, and then away to search the edge of the ice field or to feed near some 

 of the docks. It seemed to pay little or no attention to the other gulls or their 

 feeding. On the ice it ran rapidly, suggesting the action of a large plover. 



