Description
The water shrew is the largest North American member of i the longtail shrews. It typically
attains a total length of 6 inches including a tail that is between 2-3 inches. Its fur is dark gray on top and
slightly lighter on the belly with the tail also being light on the bottom and darker on top. It has a compact body, with short legs and a pointy snout. Its small eyes and ears that are barely visible. The water shrew has very large hind feet that feature fringe hairs and are slightly webbed between the third and fourth toes to enable efficient movement in the water.
Water shrews start their breeding in early spring and typically have several broods of four to eight
young by September. Water shrews use dried moss to build nests in underground burrows
under rocks and logs or in stream banks. They are active year round and will leave their burrows in winter to forage when weather permits.
The diet of the water shrew consists mainly of aquatic insects though they will consume terrestrial invertebrates--snails, slugs, spiders, beetles, centipedes and worms--
and small fish, fish eggs, as well as amphibians and their larvae. Shrews can consume over half their body weight in food each day and spend a large portion of their active hours searching for food sources.
Habitat
The Northern water shrew is usually associated with high elevation northern hardwood forests. This animal is typically found living along mountain streams characterized by cut banks, rocks, fallen logs and abundant moss and leaf litter. Water with a high quality that harbors an abundance of aquatic insects is an essential part of its habitat. In West Virginia, the water shrew has been found in Preston, Tucker, Randolph, Pendleton and Pocahontas counties at locations over 2000 feet in elevation.
Threats
Water shrews are especially vulnerable to declines in water quality and stream pollution, acidification and sedimentation that have negative impacts on the aquatic invertebrates that make up the mainstay of the shrew's diet will negatively affect the shrew. Additionally, channellization and stream bed manipulations can reduce the number of feeding pools, runways, and nest sites as can the removal of fallen logs and boulders. Other threats to this secretive animal are loss of habitat to residential and recreational development, and stream side logging.
