BIRDS IX RELATION TO MAN 



575 



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. 



The destruction of dead limbs and dead trees in forests and 



Cooper's hawk {Accipiter coopert) 



Bronzed grackle {Quiscahis quiscjdd) 



Blue-jay (Cyanocitta crisiata) 



Crow {Corvus americanus) 



Fig. 241. Some undesirable bird neighbors 



Cooper's hawk preys upon poultry and insectivorous birds. The blue-jay and the 



bronzed grackle destroy the eggs of other birds, and the grackle also eats a great deal 



of grain. The crow destroys grain, fruit, useful insects, and eggs of useful birds 



wood-lots will mean the disappearance of the downy woodpecker 

 and the red-headed woodpecker, but it is worth while to keep 

 the wood-lot clear. 



The spraying of orchard trees w-ith poisons intended to de- 

 stroy caterpillars has led to the death of thousands of birds that 



