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Species Description

• Adult total length: 9 - 12 in. (225 - 300 mm)

• Tail: 4 - 7 in. (100 - 175 mm)

• Hind foot: 1 1/8 - 1 1/2 in. (28 - 37 mm)

• Weight: 1 2/5 - 3 oz. (40 - 85 g)

• Physical Characteristics: The fur of the slender, moderate-sized native marsh rice rat varies from gray to brown with blackish hairs intermixed. The underparts and feet are whitish. The ears are small and the long, sparsely haired tail is sharply bicolored, being darker above than below. The tail is as long, or longer, than the head and body.

left lateral view of skull and mandible	dorsal view of skull	ventral view of skull

The marsh rice rat ranges from eastern Texas throughout most of the southeastern United States. It is found north to southeastern Missouri, southern Illinois, and Kentucky, and northward mainly along the Atlantic Coastal Plain to New Jersey and southeastern Pennsylvania (Linzey, 1998).

• Range Maps

  North America	Great Smokies

• Great Smoky Mountains National Park: Only one rice rat has been recorded from the park (Linzey, 1995a, 1995b). An immature female was found dead on i the sill of an old barn near a marshy creek on April 3, 1931, by the Komareks. Komarek and Komarek (1938) stated: "This record is unique in that there seem to be no records of this species occurring above 1000 feet. Its distribution was apparently extended into the mountains as a result of agricultural activities of local residents."
  • Sevier Co.: Greenbrier (2,200 feet).

Index

Natural History

• Reproduction
  The breeding season of the marsh rice rat varies. It is seasonal from March to October. Gestation lasts about 25 days with females usually bearing several litters of three to five young annually. Newborn rice rats are naked, blind, and helpless. The eyes are open and solid food is being consumed by early in their second week of life. Females may reach sexual maturity by six weeks of age.

• Longevity
  Life expectancy is generally less than one year.

• Terrestrial Ecology
  Rice rats are primarily a nocturnal terrestrial species that is active during all seasons. They are a highly carnivorous rodent feeding on carrion, crabs, clams, snails, insects, fish, baby turtles or birds, and even birds' eggs. Sometimes it eats plant material (Rose and Dueser, 1999).

• Predators and Defense
  Owls, hawks, mink, weasels, raccoons, foxes, skunks, and snakes prey on rice rats.

• Parasites
  None recorded from the park.

• eNature

Index

Acknowledgements

• Text
  • Dr. Donald W. Linzey, Wytheville Community College - wclinzd@wcc.vccs.edu
  • Christy Brecht, Wytheville Community College - wcbrecc@wcc.vccs.edu

• Photographs
  • Roger Barbour

• Map development
  • Richard Schulz, Great Smoky Mountains National Park - richard_schulz@nps.gov

• Web page design & coding
  • Denise Lim, University of Georgia, Athens
  • John Pickering, University of Georgia, Athens

• Komarek, E. V. and R. Komarek. 1938. Mammals of the Great Smoky Mountains. Bulletin of the Chicago Academy of Sciences 5 (6): 137 - 162.

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

• 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. Blacksburg, Virginia: The McDonald & Woodward Publishing Company, Inc.

• Rose, R.K. and R.D. Dueser. 1999. Marsh rice rat. Pages 554 - 555. In: D.E. Wilson, and S. Ruff (eds.). The Smithsonian Book of North American Mammals. Washington, D.C.: Smithsonian Institution Press.

• Wolfe, J.L. 1982. Oryzomys palustris. Mammalian Species No. 176: 1-5. American Society of Mammalogists.