132 BULLETIN 113, UNITED STATES NATIONAL MUSEUM. 



Egg dates. — Utah and Nevada : Fifty-six records, May 8 to June 

 26 ; twenty-eight records, May 13 to 20. North Dakota and Sas- 

 katchewan : Twelve records, June 4 to 22. California : Six records, 

 May 18 to 25. 



LABUS DELAWARENSIS Old. 



BING-BILLED GULL. 

 HABITS. 



Audubon (1840) referred to this species as "The Common Ameri- 

 can Gull," a title which would hardly be warranted to-day, although, 

 with the possible exception of the herring gull, it is the most widely 

 distributed and most universally common of any of the large gulls. 

 In Audubon's time it was probably more widely distributed and cer- 

 tainly more abundant in some localities than it is now; he refers to 

 its breeding on " several islands between Boston and Eastport, an- 

 other close to Grand Manan at the entrance of the Bay of Fundy, 

 the great Gannet Rock of the Gulf of St. Lawrence, and certain 

 rocky isles in the deep bays on the coast of Labrador." I have 

 visited all of these localities without finding or hearing of any 

 breeding colonies of ring-billed gulls, and I can not find anything in 

 the published records to indicate that they have bred at any of these 

 places in recent years, except a few shifting colonies near Cape 

 Whittle in southern Labrador, found by Mr. M. Abbott Frazar 

 (1887) in 1884, and one found by Dr. Charles W. Townsend, referred 

 to below. The ring-billed gull yields readily to persecution, is easily 

 driven away from its breeding grounds, and seems to prefer to breed 

 in remote unsettled regions, far from the haunts of man. It could 

 never survive the egging depredations which the herring gull has 

 withstood successfully ; hence its breeding range has been gradually 

 curtailed as the country has become settled. Although its former 

 breeding range was nearly as extensive as that of the herring gull, 

 it is now mainly restricted to the interior, in the lakes of the prairies 

 arid plains of the Northern States and Canada, where it far out- 

 numbers the herring gull and is still the common gull. Here it is 

 probably holding its own except where civilization is driving it out. 

 In North Dakota in 1901, in Saskatchewan in 1905 and 1906, and in 

 Manitoba in 1913 we saw it almost daily about nearly all the lakes 

 we visited and we found numerous breeding colonies. Dr. P. L. 

 Hatch (1892) stated that they had become much more numerous in 

 Minnesota through a gradual increase since 1857, being " extensively 

 distributed over the lacustrine regions of the Commonwealth, breed- 

 ing in all places adapted to their habits." 



