BIRD PROTECTION 



387 



stacles on which many birds are dashed to death in their noc- 

 turnal migrations. Telegraph, electric light, trolley car, and 

 telephone wires are all deadly and their number is constantly 

 increasing. Thousands of woodcocks (Fig. 262) and many 

 other birds are killed by flying against them. Wire fences are 

 nearly as fatal to grouse and other low-flying birds. 



Last but perhaps not least among the causes which decrease the 

 number of birds about the centers of population there must be 

 enumerated the clearing up of underbrush, shrubbery, vines, and 

 thickets. Many birds of the tangle are driven out when this 

 cover is destroyed and replaced by well-kept lawns and fields. 



FIG. 263. Cat with bird in its mouth. (After Forbush.) 



Cats. We have already introduced into this country a 

 terrible scourge to birds, the domestic cat (Fig. 263). The 

 statement that the mature cat in good hunting ground kills, 

 on the average, fifty birds a year, is certainly within bounds. 

 Kittens and half-grown cats do not catch many birds, but the 

 old cat that wanders off into the fields and woods is terribly 

 destructive. John Burroughs says that cats probably destroy 

 more birds than all other animals combined. 



