MIGRATIONS OF BIRDS 



During the summer our woods and fields are the homes of 

 vast numbers of happy birds ; but as fall approaches, they begin 

 to disappear, and before winter comes, nearly all of them have 

 gone. Late in February, the hardiest kinds begin to reappear 

 again. These are quickly followed by other varieties and in 

 early June we are once more charmed with the bright plumage 

 and sweet songs of the full chorus of birds. 



Not all the birds, however, leave us in winter. Some 

 remain throughout the year. These we call permanent resi- 

 dents. Those that come in the spring and return to the south 

 after raising their young are summer residents. Others that 

 come down from the far north to spend the winter here, are 

 winter visitants, while still others that only pass through our 

 section north and south are transient visitants. The migration 

 periods afford excellent opportunities for the study of the 

 several kinds of birds. 



Why do birds migrate? Ornithologists are not able to 

 answer the question fully, but they agree that the lack of food 

 and the severity of our climate in winter drive many varieties 

 of birds to warmer lands. But why birds leave those warmer 

 climes teeming with bird food of every kind and come back 

 through thousands of miles of distance to the colder north 

 with its short summers and scant food supply is still an 

 unsolved problem. 



Where do the birds spend the winter? Careful observa- 

 tions made over a large part of the Western Continent prove 

 that the winter homes of most of our migratory birds extend 

 from the Southern United States through the islands of the 



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