Scientific name: Blarina
Information in this Species Page was compiled by Aaron Serene in Biology 220W, Spring 2000, at Penn State New Kensington.
The Northern Short-tail shrew is a small, dark gray, "mouse-like" animal that is found abundantly throughout the Nature Trail. Shrews are members of the Order Insectivora of the class Mammalia. Insectivores are an extremely ancient groups of mammals. Fossils of insectivores dating back 130 million years have been described. Shrews and the ancestors were probably the prey of many types of small and medium sized dinosaurs!
Appearance and Venom
Shrews are opportunistic predators taking whatever prey season, habitat or opportunity presents. Prey includes mice, moles, salamanders, frogs, birds, bird eggs, all types of insects, slugs, snails, isopods, spiders, millipedes and centipedes. Shrews will also eat roots, berries, nuts, fruits, fungi and general vegetable materials if prey is limited or if these materials are abundant. Shrews must continuously eat in order to sustain their very high rate of metabolism. They are active all year round (they do not hibernate) and rely on cached food materials for consumption during times of resource limitations. A short-tail shrew must eat every two or three hours or they will succumb to starvation.
Short-tail shrews forage very actively in soil and leaf litter and even down into the burrows of other, larger animals. Their thick, stocky bodies are well adapted to pushing through dense leaf litter and vegetative debris. Shrews rely on their excellent senses of smell, touch and hearing to locate food. Their noses are richly innervated with olfactory receptors, and their snouts have dense groups of vibrissae (whiskers) to aid in tactile sensation. There is some speculation that shrews may use very high frequency vocalizations and their subsequent rebounding off objects to echolocate position and prey.
Shrews communicate primarily via scent markings and vocalizations. Two prominent sets of scent glands located on their bellies and on their flanks produce an array of pungent secretions that are used to mark individuals, territories and cache locations. Scent is also quite important for males to locate females during the breeding season which runs from March to September (but may begin even as early as January!).
The Pennsylvania State University ©2002
This page was last updated on August 07, 2003
Thank you for visiting Penn State New Kensington.