I 



Yearbook of the Department of Agriculture. 



bounties upon pocket gophers alone. Of thi> sum a single 

 county paid $11,138. One county in California paid out in 

 bounties upon ground squirrels $18,570 during 1916. Such 

 typical bounty expenditures have usually served to reduce 

 the numbers by less than the annual reproductive increase, 

 thus leaving each year a larger breeding stock of mature 

 animals to propagate, and with their progeny to continue 

 their devastating ravages upon the crops. 



GREAT DAMAGE DONE BY RODENTS. 



In States west of the Mississippi River prairie-dogs, 

 ground squirrels, pocket gophers, rabbits, cotton rats, and 

 field mice have taken a continually increasing toll from the 

 crops of wheat, oats. corn, barley, and other cereals; from 

 alfalfa, potatoes, beans, fruit, melons, and almonds; and 

 from pasture ranges. States east of this boundary have suf- 

 fered heavily from the depredations of rabbits, woodchucks, 

 and meadow, pine, and white- footed mice in gardens, field 

 and truck crops, orchards, and vineyards. The value of 

 crops destroyed annually from these sources in the United 

 States has recently been estimated to be in excess of $150,- 

 000,000. This amount is based upon information regarding 

 conditions reported by field representatives of the Biological 

 Surve} T , county agricultural agents, other competent officials, 

 and farmers; it does not include losses inflicted by house 

 mice and rats. 



Some idea of the losses suffered by individual States from 

 native rodents may be obtained from the following estimates 

 recenth' submitted by directors of agricultural extension: 

 Montana, $15,000,000 to $20,000,000; Xorth Dakota, $0,000,- 

 000 to $9,000,000; Kansas, $12,000,000; Colorado, $2,000,000; 

 California, $20,000,000; "Wyoming, 15 per cent of all crops; 

 Nevada, 10 to 15 per cent of all crops, or $1,000,000; New 

 Mexico, $1,200,000 loss to crops and double this amount to 

 range. In a single county of Virginia losses of orchard 

 trees from depredations of pine mice during the last two 

 or three 3'ears are estimated at not less than $200,000. Simi- 

 larly heavy losses are being disclosed in other States as atten- 

 tion is being directed to these causes of decreased production, 

 causes which have too frequently been overlooked, unrecog- 



