Economic Reasons for Protection 103 



and his feeding habits are similar. Most of 

 his food consists of insects, and four specimens 

 examined by Professor Aughey in Nebraska 

 contained 157 grasshoppers. 



Night hawks and whippoorwills are policemen 

 of the air, and are especially useful in that they 

 are working in the dusk and at night, when most 

 other birds are off duty. The amount of good 

 work they do is almost unbelievable. An 

 Arkansas night hawk whose stomach was ex- 

 amined, had captured six hundred insects. 

 Gnats, beetles, flies, and grasshoppers are also 

 eaten by night hawks, and seven Nebraska speci- 

 mens were found to have gathered in 348 Rocky 

 Mountain locusts. 



Swifts also capture most of their insect food 

 while on the wing, and they are apt to be found 

 on duty at any hour of the day or night. They 

 should be encouraged to nest in the chimneys 

 wherever they will. 



Flycatchers, too, catch most of their prey on 

 the wing, but unlike the swifts and night hawks, 

 they do not go far afield to hunt for it. Upon 

 some dead tree top, a telegraph pole, the gable 

 of a barn, or similar vantage point, they stand, 

 quiet but very watchful, until some luckless 

 insect comes within range of their vision. A 

 swift dive out into space, the click of a bill, and 



