The masked shrew ranges from Alaska and Canada, south through the Rocky Mountains to New Mexico, and through the Appalachian Mountains to western North Carolina and eastern Tennessee. The Great Smoky Mountains National Park is near the southern limit of the range of this shrew. Masked shrews are most commonly found among rocks and logs in moist deciduous and evergreen forests. Predators include snakes, owls, hawks, and carnivorous mammals. Eight masked shrews were found in the stomach of a bobcat taken on Newfound Gap Road in Tennessee.

Species Measurements:
- Adult Total Length: 85-100 mm (3?-4 in.)
- Tail: 30-40 mm (1?-1? in.)
- Hind Foot: 7-13 mm (? in.)
- Weight: 3-7 g (1/10-? oz.)

Physical Characteristics:
The masked shrew ranges from dark brown to brownish-gray on the back with pale gray under-parts. The tail is relatively long, and is indistinctly bicolored. Shrews have long tapering snouts, and tiny eyes and ears. Hearing and smelling are acute. The tips of the incisor teeth are a dark chestnut color. Shrews have five toes on each foot.

Habitat:
Masked shrews are most commonly found among rocks and logs in moist deciduous and evergreen forests.

Reproduction:
Little is known about breeding habits. Most masked shrews breed from spring to late summer, with females producing litters of three to six young. There may be two to three litters per year, with gestation lasting approximately three weeks. "Reproductively active" individuals were observed from mid-August to mid-October in the spruce-fir zone (Smith and Mouzon, 1985). Shrew nests are about 6 to 8 inches in diameter, with a 2 to 4 inch inside diameter, and are composed mainly of finely shredded grasses and leaves. Young are weaned, and become independent, between 3 and 4 weeks of age.

Longevity:
Masked shrews probably do not survive more than two years in the wild.

Terrestrial Ecology:
Masked shrews are active both day and night during all seasons of the year. Though primarily terrestrial, they are able to swim well.

Feeding Habits:
These shrews feed primarily on insects, spiders, worms, and other invertebrates (Linzey and Linzey, 1973).

The home range of shrews probably covers an area of up to 1 acre.

Predators and Defense:
Predators include snakes, owls, hawks, and carnivorous mammals, such as opossums, foxes, bobcats, weasels, and skunks. Eight masked shrews were found in the stomach of a bobcat taken on Newfound Gap Road in Tennessee at elevation of 3,700 feet (Linzey, 1995).

Parasites:
None recorded from the park.

The masked shrew ranges from Alaska and Canada, south through the Rocky Mountains to New Mexico, and through the Appalachian Mountains to western North Carolina and eastern Tennessee.

Masked shrews are frequently found above 3,000 feet in both deciduous and evergreen forests, although several have been taken at Smokemont (2,200 feet), along Buck Prong (2,500 feet), and 13 were taken along the Foothills Parkway, between Cove Creek and Caney Creek, at elevations ranging from 1,430 feet to 2,400 feet (Harvey, 1991). The Great Smoky Mountains National Park is near the southern limit of the range of this shrew.

References:

Harvey, M.J. 1991. Survey for Threatened and Endangered Mammals on the Right-Of-Way of Proposed Segment 8D of the Foothills Parkway. Report to the Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee.

Komarek, E. V. and R. Komarek. 1938. Mammals of the Great Smoky Mountains. Bulletin of the Chicago Academy of Science 5(6): 137-62.

Linzey, D. W. 1995a. Mammals of Great Smoky Mountains National Park. The McDonald & Woodward Publishing Company, Inc., Blacksburg, Virginia.

Linzey, D. W. 1995b. Mammals of Great Smoky Mountains National Park-1995 Update. Journal of the Elisha Mitchell Scientific Society 111(1): 1-81.

Linzey, D. W. 1998. The Mammals of Virginia. The McDonald & Woodward Publishing Company, Inc., Blacksburg, Virginia.