PROTECTION OF BIRDS 469 



10* 2Qf< 30* 40* 50* 60* 70? 80* 90* 



ire* 



Cuckoo ----------------- 1 



_. . m 



Chipping Sparrow _______ \ 



House Wren ___________ 



P 

 _____ 





 Song Sparrow ____________ I 



Rose-breasted Grosbeak 



Baltimore Oriole 



Flicker 



Phoebe '' 



Kingbird ' 



Bluebird 



Wood Thrush 



Brown Thrashec ___________ 



Robin 



English Sparrow. ....... ___ 



Crow Blackbird _________ P 



Red-haaded Woodpecker . 

 Blue Jay. 



Jie 1 



Cedar Waxwing ' 



FIG. 183. Food Chart of 25 Common Birds. 



The upper black bar represents food to the bird's discredit (grain, cultivated fruit, 

 beneficial insects) ; the lower, food to the bird's credit (' ' injurious insects ; 



Kf&'fffffffm weed seeds). The length of line is based on the percentage that these 

 foods form of the bird's total food, as determined by the Bureau of Biological 

 Survey. 



