'VERMIN, a term comparable to "weed,)) signifying small animals obnoxious in some particular to human plans and operations. Am mals may be regarded as vermin in one place which in another would be classed as innocent or even beneficial. Thus among English game keepers all the weasel tribe— stoats, polecats and weasels— are typical vermin, because they kill game and eat eggs of preserved pheasants, etc., whereas in America they are regarded as useful fur-bearers; and in the United States rats, mice and the various °gophers° are the animals which inostly fall into that class. Rats and mice, especially field mice, may increase in such numbers as to destroy large quantities .of grain and thus become decidedly destructive vermin, while serious loss may also be caused to the farmer by hares and burrowing ground squirrels, etc., especially in the Western States. Among birds, some of the hawks (see HEN HAWKS) and owls are occasionally destructive to poultry and game and have been classified as vermin; but as they feed chiefly on insects and mice, they are on the whole beneficial to man by repressing animals which are far more typically named vermin than themselves.
In the economy of nature a balance of power is rigidly observed and in the maintenance of such a balance the so-called vermin play an important part. The lemmings (q.y.) present an instance of how the equilibrium is naturally restored. It is rarely needful or wise, at any rate with reference to birds and small mam mals, for man to interfere when a case like that of the prairie-dogs (q.v.) of the western United
States arises; where repression is necessary, it is usually the result of previous human interfertnce with nature's arrangements. Agri culturists are beginning to recognize that the birds which visit their fields are of extreme value in the repression of the insects and their larvw which feed on the tender shoots of the grain. But even admitting that the fields may occasionally suffer from the visitation of com mon birds, the damage inflicted thereby.is but trifling when compared with their services in repressing the insect species. Even the much persecuted mole has been shown by Darwin to be a thorough fertilizer of the ground and the earthworm itself acts in this way also. Both animals, in fact, by their operations in turning over the soil, in bringing fresh layers to the surface and in breaking the clods, tend to open up the ground and thus to ensure favorable conditions for the germination of the seed. The despised and hunted rats al may be shown like the whellcs and crabs of the sea, to play no unimportant part in nature's sanitary arrange ments, by the wholesale destruction of offal and garbage in which they indulge. In America the use of the term vermin is often applied mainly to obnoxious insects, as fleas, bedbugs, lice, itch-mites, etc., that seek to live on human beings.