STRIKING THE BALANCE 113 



BIRDS ALMOST WHOLLY BENEFICIAL 

 Name of bird Good done 



Bob-white. Eats insect pests and weed seeds. 



Chickadee. Eats insect pests. 



Cuckoos (two species). Eat insect pests. 



Rose-breasted grosbeak. Eats insect pests and weed seeds. 



Nighthawk. Eats insect pests. 



Baltimore oriole. Eats insect pests. 

 Native sparrows (about fifty spe- Eat insect pests and weed seeds. 



cies) . 



Swallows (six species). Eat insect pests 



Vireos (six species). Eat insect pests. 



Warblers (about forty species). Eat insect pests. 



Woodpeckers (nine species). Eat insect pests. 



House wren. Eats insect pests. 



Taking one hundred species of birds as the num- 

 ber of more or less common birds that might be 

 found in a locality, they would be divided approxi- 

 mately as follows: 



Injurious 4 per cent 



Neutral 5 " " 



Chiefly beneficial 13 " " 



Almost wholly beneficial 78 " " 



Or, to state the matter still more briefly, four per 

 cent do more harm than good, and ninety-one per 

 cent do more good than harm; that is, there are 

 about twenty-two tunes as many species of bene- 

 ficial birds as there are species of harmful birds. 



So that when one comes to consider the total 

 amount of harm done by birds under all conditions, 

 and the total amount of good done under all con- 

 ditions, and when to the economic value is added 

 the great aesthetic value, we find that the amount 

 of harm done is relatively insignificant, while the 



