LIFE HISTORIES OF NORTH AMERICAN GULLS AND TERNS. 85 



the family repeated their parts of the act also. Whether all of this was mere 

 play or whether it possessed a greater significance it would no doubt be difficult 

 to determine. 



Winter. — About the middle of August, or as soon as the young are 

 able to fly and care for themselves, these gulls leave their breeding 

 grounds and wander about or start to migrate southward. They 

 sometimes appear on the Massachusetts coast in August, though not 

 regularly until September, where they are more or less common all 

 winter until the second or third week in April. Dr. Charles W. 

 Townsend (1905) records them as common on the coast of Essex 

 County, Massachusetts, from July 17 to May 1, and says, " as early 

 as July 17, 1904, 1 found seven adults in a flock of herring gulls on 

 Ipswich Beach," though these may have been summer stragglers and 

 not migrants from their breeding grounds farther north. Their 

 normal winter range extends from southern Greenland to Delaware, 

 with straggling records farther south. While wintering on our 

 coasts they associate freely with the herring gulls, with which they 

 seem to be on good terms, feeding with them on what refuse they can 

 pick up in our harbors or along the shores. They are practically 

 silent and not nearly so tyrannical as on their breeding grounds, 

 though they may occasionally be seen chasing the other gulls and 

 robbing them of their food. Adult birds can, of course, be easily 

 recognized and the superior size of the immature birds is distinctive. 

 While roosting on a sand bar or on floating ice a black-backed gull 

 always looms up large in a flock of herring gulls. They are exceed- 

 ingly shy at this season, and it is useless to attempt to approach 

 them in an open situation. 



DISTRIBUTION. 



Breeding range. — Coasts and islands of northeastern North 

 America and northern Europe. In the Western Hemisphere, from 

 North Devon Island and central western Greenland (Disco) south- 

 ward, along both coasts of Labrador to eastern Quebec (Godbout), 

 Anticosti Island, Newfoundland (Sandy Lake), Nova Scotia (Pic- 

 tou, Halifax, and Kentville) and Bay of Fundy (Isle au Haute). 

 In the Eastern Hemisphere, Iceland, Shetland, and Faroe Islands, 

 Scotland, and northern Europe east to eastern Eussia (Petchora 

 Biver), and south to about 50° N. 



Winter range. — Begularly on the coast of the United States from 

 Maine to New Jersey. More rarely north to southern Greenland 

 and south to northern Florida (St. Augustine) and Bermuda. 

 Occasionally south to Ohio (Columbus) and west to Michigan (De- 



