DAMAGE TO FOOD SUPPLY BY MAMMALS 4! 



and soon became a menace to agriculture and stock raising. It is said 

 that in ten years from 1878 to 1880, the damage done by them 

 amounted to $15,000,000, in addition to tremendous sums expended 

 in efforts to destroy them and to prevent the depredations. 21 



Many species of the squirrel family are not particularly destruc- 

 tive, but perhaps tree squirrels do sometimes take more nuts than they 

 are entitled to, though as a rule they are easily kept in check. Some spe- 

 cies of ground squirrels are much more abundant, less easily controlled 

 and decidedly injurious. In 1908 Bailey estimated the annual damage 

 done by them to agriculture and fruit raising at $i 0,000,000, 22 but 

 in 1926 he estimated the annual damage in North Dakota alone at from 

 $6,ooo~boo to $9,000,000, besides $100,000 spent in combating them. 23 

 On the other hand, some species are about as useful as harmful. 24 



Woodchucks, usually not common enough to be very injurious, 

 sometimes become plentiful about farms and may be injurious to both 

 field and garden crops. 25 Porcupines do more or less damage to forest 

 trees and sometimes make harmful raids upon shade and orchard trees. 

 One orchard in a porcupine district was unmolested for seven years, 

 then in sixteen days they killed 140 plum and cherry trees and dam- 

 aged apple trees by climbing to the tops and nibbling the fruit spurs. 26 



The larger predatory mammals directly affect our meat supply by 

 their attacks upon cattle, sheep, swine, poultry, game birds and mam- 

 mals. So great has been their destruction of stock and game on the wes- 

 tern stock ranges and in national parks and national forests, that the 

 United States Biological Survey has for a number of years been co- 

 operating with stockmen and with the U. S. Forest Service and the 

 National Park Service in campaigns against wolves, coyotes, mountain 

 lions, bobcats and lynxes. From 1914 to 1920 these campaigns resulted 

 in the capture of 109,346 coyotes and 2936 wolves, besides many 



21 Palmer, U. S. Division of Ornithology and Mammology Bull. No. 8, p. 25, 1897 ; 

 Yearbook U. S. Dept. Agric. for 1898, pp. 87-110. 



22 Bailey, U. S. Dept. Agric., Farmers' Bull. No. 335, 1908. 



23 Bailey, N. Amer. Fauna, No. 49, p. 58, 1926. See also Birdseye, Farmers' Bull., 

 No. 484, p. 10, 1912. Burnett, Off. Colorado State Entom. Circular No. 9, 1913, No. 20, 

 1916. 



24 Burnett, Off. Colorado State Entom. Circ. No. 14, 1914; No. 18, 1916. Gillette, 

 Iowa Agric. Exper. Sta. Bull. No. 6, 1889. Aldrich, South Dakota Exper. Sta. Bull. 

 No. 30, 1892. Bailey, N. Amer. Fauna, No. 49, p. 58, 1926. 



26 Birdseye, Farmers' Bull. No. 484, 1912. Bailey, N. Amer. Fauna, No. 49, p. 67, 

 1926. 



28 Hosteller, Porcupines in relation to Wyoming orchards, Seventh Ann. Rept. 

 Wyoming Board of Horticulture, pp. 25-27, 1915. 



