﻿FOOD HABITS OF THE VHIEOS 



21 



SUMMARY 



The economic value of the blue-headed vireos rests largely upon 

 their work in the consumption of caterpillars, moths, and hemipter- 

 ans. Their destruction of ladybird beetles is to be regretted. The 

 balance of favor, however, swings to the birds because of the over- 

 whelming predominance of injurious forms in the food. 



THE WHITE-EYED VIREOS 



Vireo griseus, subspp. 



The white-eyed vireos, in their subspecies, are locally common over 

 the greater part of the eastern United States and Mexico. They are 

 preeminently dwellers in damp, dense underbrush, one of their fa- 

 vored types of retreat being impenetrable growths of catbrier. In 

 such places, during the proper season, one may hear the birds giving, 

 in addition to their own song, impromptu imitations of other birds. 

 The nest is similar to that constructed by the red-eyed vireo, but is 

 placed lower, usually from 2 to 5 feet from the ground. 



In the Biological Survey's collection of stomachs are 221 of this 

 species suitable for tabulation. Eight others, nearly empty, afforded 

 additional information concerning food items. These were collected 

 over the entire range of the bird during the first 10 months of the 

 year. Vegetable matter plays a much more important part in the 

 economy of the species than in the case of either the yellow-throated 

 or blue-headed vireos, but slightly less than in that of the red-eye, 

 amounting to 11.76 per cent of the emtire food. (See fig. 7.) 



yvoA/7~/yi.y /^oo£> <a>=~ j^//S^o (P/s/^^c/^ 





iici. 7.— Monthly ijroportions of the various items in the food of the white-«yod vireos (Fi'reo griieus, 

 subsppOi based on fbe analysis of the contents of 221 stomachs, with the average of each item for the 

 year 



50209— 25t 4 



