UNITED STATES DEPARTMENT OF AGRICULTURE 



BULLETIN No. 619 & 



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Contribution from the Bureau of Biological Survey, 

 E. W. NELSON, Chief. 



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Washington, D. C. 



PROFESSIONAL PAPER 



March 8, 1918 



FOOD HABITS OF THE SWALLOWS, A FAMILY OF 

 VALUABLE NATIVE BIRDS. 



By F. E. L. Beal, Assistant Biologist. 1 



CONTENTS. 



Food habits of the swallows. . . 



Purple martin 



Cliff, or eaves, swallow 



Barn swallow 



Tree, or white-bellied, swallow 



Page. 



1 



3 



6 



11 



15 



Page. 



Violet-green swallow 19 



Bank swallow 21 



Rough-winged swallow 25 



Tabular summary 28 



FOOD HABITS OF THE SWALLOWS 



The swallows are the light cavalry of the army of birds, ever on 

 the move, always on the skirmish line, their wings tireless. From 

 early dawn until night they forage the fields of air, constantly on 

 the alert to cut off stragglers from insect camps and missing no op- 

 portunity to destroy these enemies of the farmer. From time im- 

 memorial these birds have been the friends and companions of man. 

 Whenever he has had a literature it has recorded the praise of the 

 swallow. Ever since the human race has had a history " the swallow 

 twittering from the straw-built shed" has roused the peasant at 

 break of day to resume his labors, and he has returned to his cabin 

 to rest " when the swallows homeward fly." 



All the species are more or less gregarious and appear to like not 

 only the companionship of their kind but also that of man, to whom 

 many have attached themselves, not as parasites but as cheerful com- 

 panions and helpful friends. Probably no group of birds has made 

 such a change in nesting sites as have some species of swallows, which 

 persistently use the structures of man as a shelter and foundation 

 for their nests instead of those provided by nature. 



1 Prof. Beal, the most experienced economic ornithologist in the country, died on 

 October 1, 1916, shortly after the preparation of this paper. — Editor. 



Note. — This bulletin is a technical study of the food habits of the seven North 

 American forms of the swallow family. It is for distribution in all sections of the 

 United States. 



14684°— 18— Bull. 619 1 



