36 ISLAND BIRD-LIFE 



small space. To find one nest means, practically, to find all. 

 To a large extent, the lot of one is the fortune of its neigh- 

 bors. 



Weasels may find one or more nests of Sandpipers, or 

 Sparrows in Massachusetts and devour their contents with- 

 out materially affecting the status of the species in that 

 state but the same animals on Penikese or Muskeget, would, 

 in time, doubtless anihilate the Terns which nest there. 



Wild cats, in Florida, probably never miss an opportun- 

 ity to capture a sitting Wild Turkey, but there is no evidence 

 to show that the numbers of Wild Turkeys in the state has 

 ever been seriously affected by this habit. The same ani- 

 mals, however, on Pelican Island would soon put an end to 

 all the breeding Pelicans of eastern Florida. 



Even with arboreal species, gregariousness, while nest- 

 ing, often appears to require some form of insular isola- 

 tion ; and we usually find colonies of Cormorants, Anhingas, 

 Spoonbills, Ibises and Herons, breeding on islands or in 

 trees which are growing in water and are themselves is- 

 lands. 



When, therefore, we review the islands of our Atlantic 

 Coast, from the Gulf of St. Lawrence to the Florida Keys, 

 we will not be surprised to discover how many birds, which, 

 widely distributed at other times of the year, owe their ex- 

 istence to the protection island life has accorded them in the 

 nesting season. 



On the Bird Pocks and Bonaventure are found our sole 

 remaining Gannets (Sulci basscma) ; on Old Man's Island, 

 off the Maine coast, are the only Eiders nesting in the Unit- 

 ed States ; Penikese and Muskeget held for a time our only 

 large colonies of Terns ; Martha's Vinej^ard shelters the last 

 of the Heath Hens and the only Least Terns known north of 

 the Carolinas ; Gardiner's Island is distinguished by its Pip- 

 ing Plover and Black Ducks ; Cobb's Island has almost the 

 last of the Gull-billed Terns, and Pelican Island has the only 

 nesting Pelicans of the eastern coast of Florida. 



