22 BIRDS IN THEIR RELATIONS TO MAN. 



nois, Michigan, Ohio, and Utah have vainly attempted to de- 

 stroy Hit 1 pest under the bounty system. 



"functions of the division from the stand-point of economic 



ornithology. 



" From the stand-point of economic ornithology the Divi- 

 sion may be said to have three functions: (1) to determine 

 as accurately as possible the food of birds of economic im- 

 portance ; (2) to act as a court of appeal to investigate com- 

 plaints concerning depredations of birds on crops; (3) to 

 diffuse the results of its work and educate the public as to 

 the value of birds. In studying birds' food dependence is 

 placed chiefly on examination of stomachs to ascertain what 

 has been actually eaten. Stomachs are collected in different 

 localities at all seasons and in sufficient numbers to show 

 clearly the character of the food. The stomach contents are 

 examined microscopically and identified by comparison with 

 reference collections of seeds and insects. This laboratory 

 examination is supplemented by experiment and field work. 



"INVESTIGATIONS RE(iARDIN(i SUPPOSED INJURIOUS BIRDS. 



"Species popularly considered injurious, such as hawks 

 and owls, the crow, blackbirds, woodpeckers, and blue-jays, 

 received attention first. A report on hawks and owls was 

 undertaken by Dr. A. K. Fisher, one on the crow by Professor 

 \Y. B. Barrows, assisted by Mr. F. A. Schwarz in the identi- 

 fication of insect material, while the investigations on the 

 crow blackbird, woodpeckers, and blue-jay were made by 

 Professor F. E. L. Beal. 



" The destruction of birds of prey in Pennsylvania, fol- 

 lowing the passage of the 'scalp act' of 1885, had attracted 

 wide-spread interest, and showed the necessity for correcting 

 erroneous views concerning the value of hawks and owls. 

 About two thousand seven hundred stomachs of these birds 

 were collected, the contents carefully examined, and the re- 



