The Insatiable Short-Tailed Shrew

Although short-tailed shrews are exceedingly common in the Northeast, many country dwelling people think they have never seen one. They mistake the small gray creature skittering through the leaves for a mouse!
The short-tailed shrew, known scientifically as Blarina, is about four inches long, and covered with silky, dense fur that can be brushed in either direction. He has small ears and minute eyes, almost hidden in fur. His eyesight is poor, but his senses of smell and of touch are acute. He has a very long, sensitive snout that he uses to probe in moist leaf litter and sniff out prey. Although shrews are our smallest of mammals, they are ferocious. Because of their exceedingly high rates of respiration and heartbeat, their metabolic needs make them voraciously hungry, always! They must hunt by day and by night, in the most inclement weather, with no time to hibernate. Within a day, if three shrews are confined in a box, first, two will kill and eat the third, then, by nightfall, only one victor will remain – his stomach quite full!
Although classified as an insectivore, Blarina is opportunistic and enjoys a varied menu. His long probing nose discovers in the leaf mold: insects, earthworms, slugs, snails, centipedes, salamanders and carrion. He also eats vegetable matter – especially beechnut kernels and seeds, some of which he may cache.
Even amongst shrews Blarina is unique. He has poisonous saliva! Woe to the young mouse noticed by voracious Blarina. He pounces on the hapless creature and bites it with his long, strong, hooked incisor teeth. Into the wounds flow the poisons whose effect is much like that of the cobra, and the mouse is paralyzed. Then he devours it with his numerous sharp teeth, tipped with red pigment. He can eat several times his own weight in a day!
Blarina has a gland on each side of his body that produces a strong odor, so disagreeable that some predators won't eat him. Birds don't have a good sense of smell, and owls, hawks and shrikes take him readily. He is also preyed upon by weasels, foxes, coyotes, wolves, bobcats, and house cats.
Blarina builds a spherical nest six to eight inches in diameter that incorporates dry grasses, shredded leaves, and, if available, rabbit hair. The entrance is a small opening on the side. Some shrews may shore up the edges of the nest with small stones! The nest may be built in a hollow tree, under a wood or brush pile, or in an abandoned mouse burrow. From spring to early fall, shrews may produce three litters with three to ten babies in each. The babies are born naked and helpless, and look like tiny, pink, wrinkled honey bees.
Within a month, the baby shrews are independent and are able to pursue their fierce, short lives. Because of their metabolic rate, most shrews "burn out" and survive less than one year!

More Articles by Miriam Sanders