The short-tailed shrews, sometimes called mole shrews, of the genus Blarina belong to a single species with several geographic races occupying eastern Canada and the United States, from Nova Scotia, southern Quebec, Ontario, Minnesota, and North Dakota southward to Florida and the Gulf coast as far as eastern Texas. Vertically they range from sea-level up to the tops of the Alleghenies. Another group of American shrews, containing numerous species belonging to the genus Cryptotis, occupies the mountains of the Western States, and ranges south to northern South America. In external form it is indistinguishable from the short-tailed species.
Probably no mammal is more numerous in the eastern United States than the short-tailed shrew. It occurs everywhere—in forests, in brushy areas, in old fields, and along grassy banks. Within the city of Washington it is common in Rock Creek Park, where it lives in covered runs which it makes among the grass and fallen leaves. These shrews drink frequently, and this may in part account for their abundance near streams or other water, although it may be the desirable moist soil conditions which draw them to such situations.
THE TRACK OF A COMMON COW (A SMALL ONE)
It is well to take the tracks of domestic animals as standards in identifying tracks of wild big game. The roundness of the front foot and the narrowness of the hind are general characteristics, though not always so pronounced as here. But note that the hind foot is set ahead, beside, or behind the trail of the front foot, but rarely exactly on it. This peculiarity is commonly seen in animals that are accustomed to walk on bogs. Note also the toes are set pointing a little outward, not straight forward. The clouts, or accessory hoofs, rarely show; only in deep, soft ground.
The runways of these shrews are scarcely half an inch wide, usually partly sunken in the mold or rotting surface vegetation. These are not made by digging, but by pushing aside the loose mold, and they cross and re-cross in an irregular network. They lead to the entrances to burrows which generally drop nearly straight down. The burrows are sometimes amid the leaves, but usually under the shelter of a root, stump, old log, or other cover. In addition to their own runways, the shrews make free use of the runs of meadow mice and even traverse the tunnels of the pine mice and moles in their restless search for prey.
Small rounded chambers opening off their underground runways are filled with fine grass, pieces of leaves, and other soft matter for a nest. One nest examined was made entirely from the hair of meadow mice, probably the spoils of war from the bodies of victims. As a rule, shrews are extremely unsocial, but a pair of this species is sometimes found occupying the same nest, no doubt a temporary arrangement. Several litters, containing from four to six each, appear to be born through the summer and fall, usually beginning in June.
While equally active by day and by night, the eyes of these shrews seem to be of little use except to distinguish between light and dark, but their senses of hearing and smell are highly developed, as is also the sense of touch in their long hairs, or “whiskers,” about the nose. In captivity an extreme sensitiveness is exhibited to sudden sounds, especially such as those of a bird’s wings, indicating an instinctive fear born of age-long persecution by birds of prey. Food is located by smell, and as the flexible end of the snout is moved continually from side to side, odors are caught which may register conceptions as definite in the minds of these small animals as sight does in more favored beasts. All shrews are provided with musk glands and on account of these are apparently nauseous to most other animals, as they are rarely eaten by beasts of prey. These musky secretions must be of great service to facilitate them in locating one another.
THE SHORT-TAILED SHREW, OR BLARINA