Pygmy Shrew

Photo Credit: Thomas French

SCIENTIFIC NAME: Sorex hoyi  Baird

OTHER NAMES.  Pigmy Shrew

DESCRIPTION.  The pygmy shrew is the smallest North American mammal.  Three subspecies are generally recognized in the eastern United States, with S. hoyi winnemana occurring in the south-central states including Alabama.  Pygmy shrews were once placed in the genus Microsorex, but current researchers include them in Sorex.

The pygmy shrew weighs about 1/16 to 1/8 ounce and averages 3-1/8 to 3-7/8 inches in length.  The dorsal coloration varies from reddish-brown to gray.  The undersides are grayish-white to smoke-gray tinged with light buff.

DISTRIBUTION.  Pygmy shrews are found in boreal Alaska and Canada southward to the Great Lakes area.  They are also found in the New England area of the United States and southward through the Appalachians to southern Tennessee, northwest Georgia and extreme northeast Alabama.

In Alabama, Sorex hoyi is known only from five individuals captured in and around the James D. Martin/Skyline Wildlife Management Area in extreme north Jackson County by Josh Laerm of the University of Georgia.  This species has been documented on the Cumberland Plateau of Tennessee and Georgia, and Laerm suggested that this species may occur further south on the Cumberland Plateau in Alabama.  His efforts to document the species in DeKalb County and the Talladega National Forest were not successful.

Sorex hoyi was once considered rare as they were difficult to catch with snap traps due to their size.  However, trapping success has improved with the increased use of sunken-can pitfall traps.

HABITAT.  Sorex hoyi occurs in virtually the entire spectrum of forest communities, seral stages, moisture regimes and elevations throughout the Southeast.  These shrews make tiny burrows beneath stumps, logs, and leaf litter.  Due to the wide variety of habitats S. hoyi occupies, it is unlikely that habitat is a limiting factor.

LIFE HISTORY AND ECOLOGY.  Pygmy shrews are active year-round.  Breeding records indicate S. hoyi breeds in the summer bearing 5 to 8 young.

CONSERVATION STATUS.  Due to the rarity and limited range of the species in Alabama, its status in the state is unknown.  It is classified as a species of high conservation concern.

SELECTED REFERENCES.

Choate, J. R., J. K. Jones, Jr., and C. Jones,  1994.  Handbook of Mammals of the South-Central States.  La. St. Univ. Press., Baton Rouge. 304 pp. 

Laerm, J., L. Lepardo, T. Gaudin, N. Monteith and A. Szymczak,  1996.  First Records of the Pygmy Shrew, Sorex hoyi winnemana Preble (Insectivora:Soricidae), In Alabama.  Journal. Ala. Acad. Sci. 67:43-48.

Long, C.A., 1974.  Microsorex hoyi and Microsorex thompsoni. Mammalian Species.33: 1-4.

Whitaker, J.O., Jr. and W.J. Hamilton, Jr.,  1998.  Mammals of the Eastern United States, 3^rd ed. Comstock Pub. Assoc., Cornell Univ. Press., Ithaca, N.Y. 583 pp.

Author:  M. Keith Hudson, Wildlife Biologist, Division of Wildlife and Freshwater Fisheries