ECONOMIC VALUE OF BIRDS TO THE STATE. 



35 



SWIFTS. Family Micropodidae. 



Chimney Swift (Cluztura pelagica). — No detailed study of the food of the 

 Chimney Swift appears to have been made. The species, however, so far as known, 

 is exclusively insectivorous and in view of its abundance is doubtless of much 

 economic importance. 



HUMMINGBIRDS. Family Trochilidae. 



Ruby-Throated Hummingbird {Trochilus colubris). — The juices of plants, 

 spiders, plant-lice, and other small insects constitute the food of the Humming- 

 bird, which also may be of service in pollenizing the flowers it visits. 



FLYCATCHERS. Family Tyrannidae. 



As their name indicates, the birds of this family are insectivorous. The food 

 habits of only four species appear to have been more than superficially studied. 



Kingbird (Tyranus tyrannus). — "In its food habits this species is largely 

 insectivorous. It is a true flycatcher by nature, and takes a large part of its food 

 on the wing. It docs not, however, confine itself to this method of hunting, but 

 picks up some insects from trees and weeds, and even descends to the ground in 

 search of myriapods or thousand legs. The chief complaint against the Kingbird 

 is that it preys largely upon honeybees; and this charge has been made both by 

 professional bee keepers and others. Many observers have seen the bird at work 

 near hives, and there is no reason to doubt the honesty of their testimony. One 

 bee raiser in Iowa, suspecting the Kingbirds of feeding upon his bees, shot a 

 number near his hives, but when the birds' stomachs were examined by an expert 

 entomologist not a trace of honeybees could be found. 



"The Biological Survey has made an examination of 28 \ stomachs collected in 

 various parts of the country, but found only 14 containing remains of honeybees. 

 In these 14 stomachs there were in all 50 honeybees, of which 40 were drones, 4 

 were certainly workers, and the remaining 6 were too badly broken to be identified 

 as to sex. 



" The insects that constitute the great bulk of the food of this bird are noxious 

 species, largely beetles — May beetles, click beetles (the larvae of which are known 

 as wire worms), weevils, which prey upon fruit and grain, and a host of others. 

 Wasps, wild bees, and ants are conspicuous elements of the food, far outnumbering 

 the hive bees. During summer many grasshoppers and crickets, as well as leaf hop- 

 pers and other bugs, are also eaten. Among the flies were a number of robber flies 



