BIRDS THAT EAT THE COTTON BOLL WEEVIL. 



INTRODTJCTION. 



The problem of controlling the ravages of the cotton boll weevil in 

 the United States is of such moment that it is being studied by the 

 Department of Agriculture from a number of different standpoints. 

 One of these is the relation of birds to the weevil. Accurate informa- 

 tion as to the value of our native birds as destroyers of this pest is of 

 considerable importance to the cotton grower, but such information 

 can be obtained only by means of careful and continued observation 

 in the field, supplemented by study of the stomach contents of the 

 birds. Field observations alone, unverified by stomach examinations, 

 have proved unreliable. Birds may be observed picking insects from 

 cotton plants, but it does not follow that the insects are boll weevils; 

 nor is the statement that boll weevils have been found in birds' 

 stomachs, if made by persons unaccustomed to the identification of 

 insects, to be accepted as conclusive. Insect remains in a bird's 

 stomach are nearly always in a more or less disintegrated condition, 

 so that identification of the species is difficult and requires the services 

 of a specialist. 



Investigation of the problem was begun by the Biological Survey 

 in the fall of 1904 under the direction of Vernon Bailey. The results 

 of this study, with a summary of work done by the Bureau of 

 Entomology, were published in a special bulletin by Mr. Bailey in 

 1905. '^ Stomachs of 38 species of bixds were examined, and 11 

 species were found to have eaten boll weevils. The number of 

 species known to feed on the weevil was increased to 20. 



PROGRESS OF THE INVESTIGATION. 



During 1905 investigations were continued by the Biological Survey, 

 and particular attention was devoted to the seasons about which 

 least was known — namely, the period from February to October.'' The 



a Bulletin 22, Biological Survey. 



«> Field work was carried on by James H. Gaut in three localities in Texas for periods 

 aggregating nearly six weeks, as follows: At Hempstead, Februaiy 21 to March 3; at East 

 Bernard, May 2 to 17, and at Columbus, May 18 to June 1. A considerable number of birds' 

 stomachs were obtained by him, but as no traces of the boU weevil were found in any of 

 them thev are not considered in the present bulletin. 



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