348 REPORT UNITED STATES ENTOMOLOGICAL COMMISSION. 



burnt off in Nebraska later than the middle of April, or at least the Ist of May, or else 

 some birds are sure to lose their nests or young. Stringent legislation should be in- 

 voked to stop such vandalism. The great majority, however, who indulge in such 

 practices will voluntarily abstain from them without the aid of restraining laws when- 

 ever they understand the harm that it does. 



Like the human race, birds often suffer a great deal from the conduct of their own 

 kind. Among the birds most hostile to birds are the blue jays. They rob the nests of 

 other birds of their eggs. Wantonly they often kill even the young and throw them 

 out of the nest. The increase of jays is, therefore, incompatible with the general in- 

 crease of insectivorous and other small birds, especially of those that nest on trees and 

 shrubs. It is hard for the naturalist to give up such a dandy among birds, but, as he 

 is only a blackleg in tine clothes, the feathered tribes are healthier and safer without 

 his society. 



Perhaps no bird causes such wholesale destruction among birds as the cowbird. Its 

 habit of laying its eggs in the nests of other birds, one only in a nest, and leaving 

 them to be hatched out and nourished by the foster parents to the destruction of their 

 own kind merits banishment and death. Unfortunately they are abundant in Nebraska, 

 but as attention is being directed to their bad habits a limit will soon be made to their 

 increase. Even crows and magpies do much less harm to other birds than jays and 

 cowbirds. 



DAMAGE DONE TO INSECTIVOROUS BIRDS BY BIRDS OF PREY. 



As will be seen in the part of this paper devoted to an examination of the food of 

 birds, many of the order Eaptores, or birds of prey, feed more on insects, reptiles, and the 

 small mammalia, especially mice, gophers, and ground-squirrels, than they do on birds. 

 Some indeed never or rarely feed on birds. It is, therefore, a great mistake to destroy 

 such. The following, however, feed principally on birds, and it will be best to shoot 

 them. I mention only those that are common to Nebraska, but what are found here 

 will probably all be found in Iowa and Kansas. 



Those that will carefully examine the stomachs of owls will see that the greater part 

 of them live principally on insects. In Nebraskg. the white owl {Nyctea scandiaca) de- 

 stroys small and large birds, and should be banished, but the remainder generally are 

 not chargeable with this fault. But the following members of the hawk family are 

 more or less destructive to birds : Cooper's hawk (Acclpiter cooperi), American goshawk 

 (Asiur atrlcapillus), prairie falcon (Falco polyagrus), duck-hawk {F. comwiMwis), American 

 merlin (F. richardsoni), sparrow-hawk (F. sparverius). This last will be seen to destroy 

 an equal quantity, in bulk, of insects, small mammalia, and birds. The same can be 

 said of the hen-hawk (Buteo horealis). Swainson's buzzard (Buteo swainsoni) is in many 

 sections looked on as an especial foe to birds ; but it is doubtful whether it eats any- 

 thing besides insects, the smaller mammalia, and reptiles. The cases when it captures 

 a bird must be rare. The American rough-legged hawk (Archibuteo lagopus, var. sancii- 

 Johannis) also live mostly on other than bird-food, although regarded by many as 

 specially obnoxious. For the sake of having as great a variety as possible of insectiv- 

 orous birds, if for no other reason, it is certainly desirable to preserve all the birds of 

 prey that are not injurious to the feathered tribes. For this purpose it is important for 

 people to learn to distinguish between the useful and the injurious Raptores. 



It has been suggested that the general economy of Eature in the fertilization of 

 plants would be interfered with by a general destruction of insects. But in Nebraska, 

 at least, there are no plants of economic importance that would suffer from such a re- 

 sult. Even the few species of orchids in this Territory would continue to attract in- 

 sects enough to perpetuate their kind. I have observed the Buffalo berry (Sheperdia 

 argopliylld) to be fertilized by insects. But where this shrub is cultivated the stam- 

 inate and pistillate individuals can be placed close enough to be fertilized by the winds. 

 Red clover is not yet grown to any extent, and it is doubtful whether this plant is as 

 dependent on insect agency for its fertilization as some authors have maintained. 



