206 BIRDS IN THEIR RELATIONS TO MAN. 



times lizards enter largely into the bird's diet. Professor 

 King reports that of seven sparrow-hawks which he examined 

 in Wisconsin "two had eaten two mice; four, twenty-five 

 grasshoppers ; three, twenty-five crickets ; one, six beetles ; 

 one, live moths ; and one, two hairy caterpillars. One was 

 seen to take a young robin from the nest and one to capture 

 another bird not identified."' Ten Nebraska specimens ex- 

 amined by Professor Aughey had eaten large numbers of 

 insects, comparatively few being locusts; three of them had 

 also eaten mice, three others gophers, one a rabbit, one a 

 quail, one an unidentified bird, and one some frogs. All the 

 evidence goes to show that the sparrow-hawk preys only to 

 a limited extent upon our native insectivorous birds. 



The Broad-winged Hawk is comparatively a common species 

 throughout eastern North America, spending the winter south 

 of the fortieth degree of latitude, but coming north for the 

 summer. It breeds in trees, building a bulky nest similar to 

 that of other common hawks ; and feeds on mice, frogs, small 

 snakes, toads, crayfish, chipmunks and red squirrels, earth- 

 worms, and many insects, — making a specialty among the 

 latter of the large caterpillars of the sphinx- and emperor- 

 moths, such as the cecropia-caterpillar so often destructive to 

 shade-trees. This is one of the few birds that venture to 

 attack these formidable-looking creatures. This hawk very 

 seldom attacks poultry or small birds. 



Several species of the birds of prey are of great benetit to 

 man as insect destroyers. In the Western States none of 

 them surpasses in this respect the common Swainson's Hawk, 

 a large bird which during the late summer and early autumn 

 months feeds to so great an extent on grasshoppers and their 

 allies that it might well be called a grasshopper hawk. The 

 evidence on this point is abundant and conclusive, as is also 

 that in regard to the work this bird does in destroying ground- 

 squirrels (Spermophiles) and related pests. Flocks of several 

 hundreds of these hawks have repeatedly been seen foraging 



