ECOLOGY AND WILD LIFE CONSERVATION 483 



the north central states. Spring hunting was abolished and the fall sea- 

 son was greatly shortened, the bag limit was drastically reduced, and 

 other restrictions were placed on hunting. Federal refuges from Canada 

 to the Gulf Coast were developed to furnish food and safety for migrat- 

 ing birds in order to save enough for breeding stock the following spring. 

 Hundreds of acres of wild life food plants were planted around artificial 

 ponds on the refuges and soon millions of ducks and geese were finding 

 protection there. A group of private individuals raised millions of dol- 

 lars to improve the nesting sites of waterfowl in Canada where the 

 majority of the birds nest and raise their young. As a result of all 

 these efforts, there has been a moderate increase in the population of 

 ducks and geese, but the permanent loss of proper habitat due to the 

 growing human population makes further increase doubtful. 



The Role of the Predator 



A large number of animals (mammals, birds, reptiles, amphibians, 

 and fish) are carnivorous ; that is, they eat the flesh of other animals. 

 When they kill animals that are of value to man, it has been customary 

 to regard them as obnoxious predators which should be destroyed. 

 Stories of the "sly fox" or the "big, bad wolf" are present in many 

 nursery tales and inculcate a hatred of such animals in young children. 

 Modern ecologists have proved this view erroneous and have shown that 

 predators have an important role in maintaining the balance of nature. 

 If all the hawks and owls are destroyed, rodents become a serious pest. 

 This actually happened in parts of Pennsylvania some years ago, where 

 a bounty was paid on these birds. Rats and mice became so abundant 

 when their natural checks were removed that farm crops were badly 

 damaged. A pair of barn owls nesting in a barn have been estimated 

 to save the lucky farmer twenty-five dollars worth of grain a year. 

 Similarly a pair of red-shoulder hawks (better known as mouse hawks) 

 nesting in his wood lot and patrolling his meadows and farm lands all 

 day may be worth the same amount. Even the fierce Cooper's hawk, 

 often known as the chicken hawk, may actually serve an important func- 

 tion in keeping wild life healthy. Such gregarious upland game birds 

 as the quail are often attacked by contagious diseases which may spread 

 rapidly through the whole covy. However, when a Cooper's hawk- 

 swoops down on the covy, the sick bird will be too slow to escape and 

 will be caught and devoured by the hawk before the disease has had 

 time to spread ; the hawk will also remove birds with hereditary weak- 

 nesses. For these reasons predators are often spoken of as the doctors 

 of the wild who not only prevent the spreading of a disease but also 



