Page:Popular Science Monthly Volume 91.djvu/932

 Consider the Rat

The most destructive mammal that lives with man.. It costs $200,000,000 to keep our rat population every year

By Fred Telford

RATS probably destroy more property than any other mammal. They are a luxury hard to support. A little incident reported by Edward Howe For- bush, Massachusetts state ornithologist, in his booklet "Rats and Rat Riddance," il- lustrates the prevailing ignorance. with regard to the depredations of this un- conscionable pest.

A grocer in a Massachusetts town com- plained to his landlord of the injury to his stock caused by rats, and asked to have the building made rat-proof. As this in- volved considerable changes, the landlord proposed that he pay the amount of the dam- ages instead. When he was presented with a bill for $25 at the end of the first month, however, he refused to believe that the damage was really so great until shown the ruined goods. Then he decided it was cheaper to make the building rat-proof. When this was done and the rats in the building destroyed by phosphorus, the depredations ceased.

Just at present the damage done by rats is particularly serious because their principal food is grain and grain prod- ucts. Corn is eaten both in the field in the shock, and in the crib. Wheat if not ac- tually consumed is rendered unfit for the table or manger farmer had such a numerous colony of rats that they destroyed one-fourth of the corn in two cribs containing two thousand bushels. He killed as many as one hundred and fifty rats a day.

The rat population of farms of all kinds where grain for food is abundant is nothing less than startling. An Illinois farmer killed 3,435 rats on his farm, while on two Georgia rice plantations it was estimated that forty-seven thousand rats were killed during the spring and summer of one year. A rat hunt in Ohio, with sides chosen, yielded over eight

916

����Wires from which the insula- tion has been gnawed by rats

An Iowa

��thousand rats. Many ships also have a big rat population; when the steamer Minnehaha was fumigated at London some

years ago seventeen hundred

rats were killed.

100,000,000 Is Our Rat Population

The most reliable estimates of our rat population are based upon the figures ob- tained in the rat-killing cam- paigns instituted when the bubonic plague, a rat-borne disease, invaded the United States a few years ago. In the first four months of the campaign about 130,000 rats were killed in San Francisco; up to May, 1908, 278,000 were actually captured, and probably 500,000 poisoned. The most careful estimates place our rat population at 100,000,000, or about a rat per person.

The direct cost of main- taining this enormous rat population mounts into large figures. David E. Lantz, assistant biologist for the United States department of Agriculture, several years ago estimated that the cost of feeding a rat on grain was from 60 cents to $2 a

���A few examples of the rat's costly depredations

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