496 



THE NATIONAL GEOGRAPHIC MAGAZINE 



The whippoorwills, swift of wing and 

 with capacious mouths beset with bris- 

 tles, attend to the night-flying insects 

 when most birds are asleep, while the 

 hawks by day and the owls by night sup- 

 plement the work of other birds and have 

 a special function of their own, the de- 

 struction of noxious rodents. 



Thus every family of birds plays its 

 own part in the warfare against insects 

 and other foes to man's industry, and 

 contributes its share to man's welfare. 



Birds would fall far short of what they 

 accomplish for man were they not the 

 most active of living things. It is curious 

 that the group of vertebrates which live 

 the fastest — that is, have a higher tem- 

 perature and a more rapid circulation 

 than any other — should be related by de- 

 scent to a family of such cold-blooded 

 creatures as the reptiles and lizards, 

 which often go without food and hiber- 

 nate for considerable periods. Very dif- 

 ferent is it with birds. Few realize the 

 enormous quantity of food required to 

 sustain the energy of these creatures, 

 most of whose waking hours are spent 

 in a never-ending search for food. 



In satisfying their own hunger birds 

 perform an important service to man, for 

 notwithstanding the fact that the acreage 

 under cultivation in the United States is 

 larger than ever before, and that the 

 crops are greater, the cost of foodstuffs 

 continually mounts upward. Meanwhile 

 the destruction of farm and orchard 

 crops by insects and by rodents amounts 

 to many millions each year, and if any 

 part of this loss can be prevented it will 

 be so much clear gain. 



The protection of insectivorous and 

 rodent-destroying birds is one of the 

 most effective means of preventing much 

 of this unnecessary loss, and the public 

 is rapidly awakening to the importance 

 of this form of conservation. From the 

 farmers' standpoint, such birds as the 

 bobwhite, prairie-chicken, the upland 

 plover, and the other shore birds are 

 worth very much more as insect eaters 

 than as food or as objects of pursuit by 

 the sportsman. This statement applies 

 with especial force to such species as the 

 prairie-chicken, which everywhere in its 

 old haunts is threatened with extinction. 



BIRDS CHECK RAVAGES OF DISEASE- 

 CARRYING INSECTS 



The value of birds to the farmer is 

 plain enough, but we do not usually think 

 of birds as having any direct relation to 

 the public health. To prove that they do, 

 however, it is only necessary to state that 

 500 mosquitoes have been found in the 

 stomach of a single night-hawk; that in 

 a killdeer's stomach hundreds of the 

 larvae of the salt-marsh mosquito have 

 been found, and that many shore birds 

 greedily devour mosquito larvae. As 

 mosquitoes are known to carry the germs 

 of such serious diseases as dengue fever 

 and malaria, it is evident that by destroy- 

 ing them birds are conferring an impor- 

 tant benefit on man. It may be added 

 that not infrequently ticks are eaten by 

 birds, and that the tick responsible tor 

 the spread of Texas fever among cattle 

 has been found in the stomach of the 

 bobwhite. 



Since birds perform such invaluable 

 service, every effort should be made to 

 protect the birds we now have and to in- 

 crease their numbers. This can be done 

 in several ways: (a) by furnishing nest- 

 ing boxes for certain species to nest in, 

 as swallows, martins, wrens, woodpeck- 

 ers, great-crested flycatchers, and others ; 

 (b) by planting berry-bearing shrubs 

 about the farm or orchard as food for 

 the birds in winter; (c) by the establish- 

 ment of bird santuaries, where birds may 

 be reasonably safe from their natural 

 enemies and be permitted to live and 

 breed in absolute security as far as man 

 is concerned. 



Here, again, the National Government, 

 taking the lead, has set apart no less than 

 64 bird refuges in various parts of the 

 United States. These for the most part 

 are rocky, barren islands of little or no 

 agricultural value, but of very great use- 

 fulness in the cause of bird protection. 

 The example thus set is now being fol- 

 lowed by certain States, as Oregon and 

 Wisconsin. Several private citizens also 

 have acquired islands for the purpose of 

 making bird preserves of them ; others 

 not only prevent the destruction of wild 

 life on their forested estates, but go much 

 farther, and endeavor in various ways to 

 increase the number of their bird tenants. 



