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Texas Invasive Species Institute

Texas Invasive Species Institute

Gambian Rat

Cricetomys gambianus

Class: Mammalia
Order: Rodentia
Family: Muridae

Cricetomys gambianus

Photographer: Poskan Komentar Source: http://mouflonhl.blogspot.com/2010/08/tikus-datang-membantu.html


The Gambian rat (Cricetomys gambianus), also referred to as the gambian pouched or African giant pouched rat, is among the largest rat in the family Muridae with an average length of 3 feet including the tail. The gambian rat can weigh as much as 9 lbs, which is comparable to a small domestic cat. A distinguishing feature of the gambian rat is the hairless tail, accounting for almost half of the animal's total length. As a nocturnal animal, the gambian rat doesn't see very well, but has a keen sense of smell and hearing. In its native continent of Africa, the gambian rat is used to detect underground mines.

Ecological Threat

The gambian rat is a large aggressive animal that poses the greatest threat to crops and smaller native species found in the Florida keys. Many endangered species are at the greatest risk from the gambian rat due to its ability to out-compete for resources combined with a high fecundity. The gambian rat differs from other rodents because of its ability to store grains and food in cheek pouches. This allows for greater consumption of food at one time and an increased potential to damage crops.


Gambian rats are omnivorous, and are known to consume vegetables, insects, crabs, snails, palm kernels, and palm fruits. As a member of the genus Cricetomys, which is known for a high fecundity, the gambian rat is able to complete gestation in 27 to 42 days, producing a litter of 1 to 5 young.


Eight gambian rats were accidentally released in 1999 by an exotic animal breeder in the Florida keys. Local experts believe the gambian rat is responsible for the introduction of the viral disease monkeypox in 2003, which was spread to prairie dogs purchased as pets. Shortly thereafter, the CDC and FDA issued a ban on distribution and sale of imported rats.

Native Origin

Native Origin: Africa

Current Location

U.S. Habitat: Gambian rats can be found in a variety of habitats near man-made establishments or in a forest. Shelters are underground and usually in the most shaded areas to keep the burrow cool and protected. As an omnivorous animal, the gambian rat can survive off a variety of food allowing for establishment in a variety of places where small invertebrates or vegetation are available.

U.S. Present: Florida Keys


Gambian rats are currently restricted to the Florida keys due to natural barriers preventing migration to the Florida mainland. It isn't entirely impossible for the rats to cross automobile bridges to the Florida mainland, so local experts are working to eradicate the isolated population before it spreads. The best current management methods are rat poison if an infestation is suspected, and notify local Fish and Wildlife authorities immediately to assist in eradicating the population.  




Ajayi, S. S. 1975. Observations on the biology, domestication, and reproductive performance of the African giant rat Cricetomys gambianus (Waterhouse) in Nigeria. Mammalia 39:344364.

Barbour, D. B. and S. R. Humphrey. 1982. Status and habitat of the Key Largo woodrat and cotton mouse (Neotoma floridana smalli and Peromyscus gossypinus allapticola). Journal of Mammalogy 63:144148.

Cook, J. L., and D. J. Richardson. 2010. Epifaunistic earwigs (Dermaptera: Hemimerina) associated with Emin's pouched rat (Cricetomys gambianus) in Cameroon, Africa. Entomological News 121(4): 397-399.

Drake, J. M. 2005. Risk analysis for invasive species and emerging infectious diseases: concepts and applications. American Midland Naturalist 153:419

Perry, N. D., B. Hanson, W. Hobgood, R. L. Lopez, C. R. Okraska, K. Karem, I. K. Damon, D. S. Carroll. 2006. New invasive species in southern Florida: Gambian rat (Cricetomys gambianus). Journal of Mammalogy 87:262-264.

Internet Sources


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