BIRD KEY 



OME land birds 

 have the custom 

 of gathering in 

 large numbers at 

 certain favorite 

 spots to pass the 

 night. There are 

 well known robin roosts, and buzzard roosts, and 

 crow roosts, and nightly gatherings of swifts, 

 martins and other birds. The number of species which do 

 this is not large, and those which dwell in communities 

 while rearing their young is even smaller. 



With birds of the sea the reverse is the case. They often 

 accumulate in countless thousands on some lonely shore 

 for the purpose of rearing their offspring, sometimes many 

 species being thus associated. Of the gulls, petrels and 

 other birds which throng certain rocky islands in the Gulf 

 of St. Lawrence, Mr. Chapman and other naturalists have 

 told us. The Farallone Islands, lying in the Pacific Ocean 

 about thirty miles from San Francisco, are famous for 

 their abundance of bird life. 



On some of the South American islands flocks of feath- 



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