feeding on schools of small fish. More 

 frequently they paddle slowly on the sur- 

 face dunking their heads (surface dipping, 

 Ashirole 1971), fly a few feet up from this 

 position and make short plunges in shallow 

 water (surface plunging, Ashmole 1971), or 

 forage over exposed tidal flats or inter- 

 tidal rocky substrates. Some of their 

 feeding techniques show remarkable ingenu- 

 ity. They paddle in shallow water, creat- 

 ing a current that moves away sediments to 

 expose infaunal prey. It is not uncommon 

 to see gulls cracking mollusc shells by 

 dropping them from the air onto docks, 

 boulders, parking lots, or any other large 

 hard object. 



flost New England terns are smaller 

 than the gulls. Some kinds with forked 

 tails are aptly called sea swallows. Their 

 speed and flight patterns, particularly 

 when being pursued by one of their own 

 kind, are remarkable to watch. They are 

 most famous for their group feeding "fren- 

 zies" when they plummet head first from 

 the sky to capture schooling fish and 

 crustaceans. More gracefully, on calm 

 days they can swoop down and snatch a 

 minnow without making a ripple. While 

 searching for food, they may be seen hov- 

 ering or "stilling". Their relatively 

 small feet serve to orient them but pre- 

 vent them from being good swimmers. Prey, 

 usually small fish or crustaceans, are 

 generally captured by plunge diving. 



At the turn of the century, no one 

 would have predicted that "sea gulls" 

 would become a symbol of the New England 

 seashore. During the last two hundred 

 years, the breeding populations of New 

 England gulls and terns have fluctuated 

 greatly. Surveys have been made at fre- 

 quent intervals during this century and 

 there is good documentation for recent 

 periods of both declines and expansions. 

 The following discussion of the historical 

 trends in these populations is summarized 

 from Drury (1973) and Nisbet (1973). 



During much of the 18th and 19th cen- 

 turies, the larger gulls were exploited 

 for their food value and nearly extermi- 

 nated in New England, and in the later 

 decades of the 19th century, the millinery 

 trade inflicted hunting pressures on terns 

 as well. By 1900, both gull and tern 

 populations were at low levels, and some 



conservationists feared these species were 

 on the verge of disappearing from the New 

 England coast. A conscious effort to save 

 these birds resulted in the passage of 

 several bird protection laws and the 

 response of the bird populations has been 

 good to spectacular for terns and gulls 

 respectively. 



The New England herring gull breeding 

 population numbered only about 10,000 

 pairs at the turn of the century, with the 

 great majority restricted to islands off 

 the Maine coast. Both the number and 

 range of gulls have increased tremendously 

 in the last 75 years. From 1900 to the 

 1960's, the population appears to have 

 increased by a factor of 15 to 30, dou- 

 bling every 12 to 15 years (Kadlec and 

 Drury 1968). As early as the 192C's, there 

 was concern that the rapidly increasing 

 herring gull population threatened farm 

 and blueberry crops in eastern Maine as 

 well as the continued survival of the 

 terns; in the 1930's, a gull control 

 program was initiated in the form of egg 

 spraying. This was originally focused in 

 Maine and the gulls responded in part by a 

 southwestward expansion into Massachusetts 

 (Kadlec and Drury 1968). During the 1940's 

 to early 1950's, the control program was 

 conducted on most colonies from Maine to 

 Massachusetts, but was eventually aban- 

 doned as ineffective. Although gulls col- 

 onized islands at the eastern end of Long 

 Island Sound by 1933, it was not until 

 1950 that herring gulls colonized the 

 shores of Connecticut. By 1960, they had 

 expanded their range as far south as North 

 Carol ina. 



The common tern has been the most 

 abundant tern nesting on the northeastern 

 coast of the United States, although the 

 Arctic tern may now be more numerous in 

 Maine (W.H. Drury; College of the Atlan- 

 tic; Bar Harbor, Maine; April 1981; per- 

 sonal commiunication). Historical popula- 

 tion estimates indicate a period of 

 increase early in this century followed by 

 a more recent period of decline in popula- 

 tion numbers. Peak populations occurred 

 during the 1940's and since then, the pop- 

 ulation has been reduced by about one 

 half. One author suggests that the 

 decline of these birds may be due in part 

 to decreased breeding success that has 

 resulted from the displacement of breeding 



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