"The annual losses from rodent pests in the United States have been estimated as fully $300,000,000. About two-thirds of the damage is inflicted by house rats and mice (both introduced from the Old World) and the remainder by native species. This enormous waste of resources may be greatly reduced and largely prevented through systematic and organized campaigns against the noxious species. The bounty system effects no permanent relief from rodents and is far more costly than the use of poisons. The Bureau of Biological survey has developed and perfected practical methods of extermination which have been successfully applied over wide territory. The Bureau cooperates with the public in organizing and carrying out systematic campaigns against animal pests and invites correspondence on the subject. Protection of their natural enemies is urged as an important aid in controlling rodent pests." -- p. [2]
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