American Water Shrew

About the American Water Shrew

The American water shrew or northern water shrew (Sorex palustris) is a shrew found in the nearctic faunal region located throughout the mountain ranges of the northern United States and in Canada and Alaska. The animal resides in semi-aquatic habitats, and is known for being the smallest mammalian diver.

The American water shrew is a sexually dimorphic species in which the males are generally larger and heavier than the females. The size of the shrew is 130–170 mm (5.1–6.7 in) and weight is 8–18 g (0.28–0.63 oz). Their tail length is 57–89 mm (2.2–3.5 in). The shrew exhibits a black and brown pelage which varies in shade depending on the season. When underwater, the animal appears to have a silver veneer on account of its water repellent fur trapping air bubbles. The snout features vibrissae which in the case of water shrews are specialized for aquatic hunting. Like other small mammals who spend part of their time in water, American water shrews have short hairs covering their hind limbs to bolster each paddle with increased surface area, an adaptation not dissimilar to flippers. Externally the American water shrew is indistinguishable from the western... Wikipedia →