CHAPTER LXXVII 

 BIRDS IN RELATION TO MAN 



452. The food of birds. As in the case of most animals, 

 birds are important to us chiefly because of the food they eat. 

 But unlike most insects, the feeding of birds usually turns out 

 to be of advantage to mankind. Observation has convicted 

 many birds of eating fruit in the orchards, and the sharp- 

 shinned hawk has been caught carrying off hens from the 

 barnyard. But the systematic study of the contents of birds' 

 stomachs has shown that most of the food of practically all 

 the common wild birds consists of insects, the seeds of various 

 undesirable weeds, and field mice, shrews, mice, and other un- 

 desirable animals. In other words, with a very few exceptions, 

 the common birds are worth more alive than dead. The value 

 of most wild birds as destroyers of insects, vermin, and weeds 

 is vastly greater than their value as sources of feathers, as 

 food, or as objects of sport. 



453. Destruction of birds. Many birds are destroyed wantonly 

 by ignorant boys and men, others are killed to supply feathers, 

 and still others are exterminated in the destruction of eggs and 

 nests out of idle curiosity or in the interests of untrained col- 

 lecting. In rural and suburban districts the domestic cat is a 

 serious menace to the native birds, and does damage that is far 

 from compensated for by the mice or rats killed by the cats. 



During their migrations many birds are killed by flying 

 against telephone and telegraph wires, and against plate-glass 

 windows. Along the shores, migrating birds frequently hover 

 about the lighthouses at night until they are exhausted. The 

 extension of cities, the clearing of forests, and the improvement 

 of farms are all tending to exterminate various species of birds. 



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