Choctawhatchee Beach Mouse

Peromyscus polionotus allophrys

Description

The Choctawhatchee beach mouse has a small body, haired tail, relatively large ears, and protuberant eyes. Its head and body length is 2.7-3.5 in (6.8-8.9 cm), plus a tail of 1.7-2.5 in (4.3-6.4 cm). Its upper parts are colored orange-brown to yellow-brown, the underparts are white, and the tail brownish with a variable dorsal stripe.

Behavior

The Choctawhatchee beach mouse probably feeds at night on grass seeds, roots, stems, and insects. It digs tunnel systems and living chambers within the root network of dune vegetation. It gives birth to several generations each year of naked, helpless young, which are raised by the female. Breeding may occur at any time of the year, but peaks during the fall and winter. The litter size ranges from two to seven. Beach mice are monogamous and remain in the same home range until the death of either mate. Their average lifespan is 180 days. Females reach sexual maturity at six weeks of age.

Habitat

The Choctawhatchee beach mouse inhabits sparsely vegetated, but mature, coastal sand dunes. It prefers areas with varied topography, and high densities of crab burrows as escape cover.

Distribution

The Choctawhatchee beach mouse was originally found along the Gulf of Mexico, between Choctawhatchee and St. Andrew Bays.

Threats

The recent distribution of the Choctawhatchee beach mouse is limited to two areas: about 4.9 mi (7.4 km) of beach from near Morrison Lake eastward to Stalworth Lake (Topsail Hill area, Walton County), and Shell Island at St. Andrews Bay in Bay County. In 1979, the total population was conservatively estimated at 515, including 357 beach mice on Shell Island and 158 in the Topsail Hill area. The Choctawhatchee beach mouse is threatened by beach development that decreases the extent and quality of its natural habitat, including residential and commercial development, the construction of roads, and recreational use. About 60% of the original habitat has been lost in these ways. Non-native house cats (Felis catus ) are thought to be a major predator. In addition, the introduced house mouse (Mus musculus ) appears to be competing with the Choctawhatchee beach mouse for food and cover, and may have displaced the rare mouse in the mainland portion of St. Andrews State Recreation Area. Human dwellings in the vicinity of beach mouse habitat serve as points of introduction for house mice and feral cats. Because of its small abundance and few populations, the rare beach mouse is threatened by extreme events of weather, such as hurricanes.

Conservation and Recovery

The most necessary conservation measures in support of the Choctawhatchee beach mouse are the preservation of the remaining privately owned, mature sand-dune systems, and the protection and enhancement of publicly owned habitat at the Gray-ton Beach State Recreation Area, Walton County; at the St. Andrews State Recreation Area, Bay County; and on the Tyndall Air Force Base on the eastern end of Shell Island, Bay County. Management actions include: the strict exclusion of off-road vehicles from sand-dune habitat; control of pedestrian access across the dunes by limiting transits to boardwalks; and the planting of native dune vegetation to stabilize severely eroded areas. It is also necessary to control or eliminate feral cats and house mice in the critical habitat of the endangered beach mouse. Recovery efforts undertaken for the Choctawhatchee beach mouse include the release in 1987-1988 of 30 animals in suitable habitat in Grayton Beach State Recreation Area. Surveys indicate that these mice are reproducing. In addition, the Alabama Cooperative Wildlife Research Unit at Auburn University is maintaining a captive-breeding facility for endangered beach mice.

Contacts

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
1875 Century Blvd., Suite 200
Atlanta, Georgia 30345
http://southeast.fws.gov/

U. S. Fish and Wildlife Service
6620 Southpoint Drive South, Suite 310
Jacksonville, Florida 32216-0958
Telephone: (904) 232-2580
Fax: (904) 232-2404

Reference

U. S. Fish and Wildlife Service. February 1991. "U.S. Fish and Wildlife Service Endangered Species, Species Accounts: Choctawhatchee Beach Mouse, Peromyscus polionotus allophrys. "U.S. Fish and Wildlife Service Endangered Species Program. (http://endangered.fws.gov/i/a/saa8d.html).

U. S. Fish and Wildlife Service. 1985. "Endangered and Threatened Wildlife and Plants: Determination of Endangered Status and Critical Habitat for Three Beach Mice." Federal Register 50 (109): 23872-23889.