Gambian pouched rat

Gambian pouched rat
Conservation status
Least Concern (IUCN 3.1)[1]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Rodentia
Superfamily:	Muroidea
Family:	Nesomyidae
Subfamily:	Cricetomyinae
Genus:	Cricetomys
Species:	C. gambianus
Binomial name
Cricetomys gambianus Waterhouse, 1840

The Gambian pouched rat (Cricetomys gambianus), also known as the African giant pouched rat, is a nocturnal pouched rat of the giant pouched rat genus Cricetomys. It is among the largest muroids in the world, growing up to about 0.9 metres (3 ft) long including their tail which makes up half their length.^[2] It is widespread in Sub-Saharan Africa, ranging geographically from Senegal to Kenya and from Angola to Mozambique (although it is absent from much of the DR Congo, where Emin's pouched rat is present) and in altitude from sea level to 2,000 metres (6,600 ft).^[1] It is also an invasive species in Grassy Key in the Florida Keys.^[3]

Characteristics

The Gambian pouched rat has very poor eyesight and so depends on its senses of smell and hearing. Its name comes from the large, hamster-like pouches in its cheeks. It is not a true rat but is part of a uniquely African branch of muroid rodents. It typically weighs between 1 and 1.4 kilograms (2.2 and 3.1 lb).^[2] In its native Africa, this pouched rat lives in colonies of up to twenty, usually in forests and thickets, but also commonly in termite mounds. It is omnivorous, feeding on vegetables, insects, crabs, snails, and other items, but apparently preferring palm fruits and palm kernels.

Unlike domestic rats, it has cheek pouches like a hamster. These cheek pouches allow it to gather up several kilograms of nuts per night for storage underground. It has been known to stuff its pouches so full of date palm nuts so as to be hardly able to squeeze through the entrance of its burrow. The burrow consists of a long passage with side alleys and several chambers, one for sleeping and the others for storage. The Gambian pouched rat reaches sexual maturity at 5–7 months of age. It has up to four litters every nine months, with up to six offspring in each litter. Males are territorial and tend to be aggressive when they encounter one another; otherwise, this rodent is extremely friendly and has become popular as an exotic pet. It is intelligent, social and can be very gentle if handled from an early age. However, feral subjects have been known to attack humans living in cramped conditions.

In Africa, it is routinely eaten as bushmeat.

Invasive threat

Currently, these rats have become an invasive species on Grassy Key in the Florida Keys. Perry et al. (2006) confirmed that animals found on the island are, in fact, representative of a breeding population and are not isolated escapees. It is unknown how the rat was released to the wild, and there is fear that if the rats reach Key Largo, they could invade the Everglades and cause great ecological damage. As fruit eaters, the rats also pose a huge agricultural threat to South Florida, prompting USDA leadership in the trapping effort. Peterson et al. (2006) determined through computer modeling that C. gambianus (and, to a lesser degree, C. emini) has strong potential to be successfully invasive across much of the mainland U.S., particularly the Southeast. Biologists say it would compete for food with native species, carry diseases, and damage the bird population by eating their eggs.

In late August, 2011, press reports indicated the species had established at least a toehold in the New York City area.^[4]

This outsized African rodent is also believed to be responsible for the current outbreak of monkeypox in the United States. In 2003, the United States' CDC and FDA issued an order preventing the importation of the rodents following the first reported outbreak of monkeypox. Around 20 individuals were affected.^[5] Several African species are believed to carry the disease.

In September 2008, the FDA and CDC lifted the ban on pouched rats as pets in the United States. They are still illegal to import from outside the U.S.^[6]

Ability to detect land mines and tuberculosis by scent

Main article: APOPO

A Tanzanian social enterprise founded by two Belgians called APOPO, trains Gambian pouched rats to detect land mines and tuberculosis with their highly developed sense of smell. The trained pouched rats are called HeroRATS.

See also

• APOPO
• Giant pouched rat

References

1. ^ ^{a b} van der Straeten, E., Kerbis Peterhans, J., Howell, K. & Oguge, N. (2008). "Cricetomys gambianus". IUCN Red List of Threatened Species. Version 2009.1. International Union for Conservation of Nature. http://www.iucnredlist.org/apps/redlist/details/5522. Retrieved 11 July 2009. 
2. ^ ^{a b} Kingdon, J. (1997). The Kingdon Field Guide to African Mammals. p. 199-200. ISBN 0-12-408355-2
3. ^ Rat & Mouse Gazette: African Giant Pouched Rats as Pets, July/Aug 1997
4. ^ "Virginia girl found eating herself in cage in mobile home; parents Brian and Shannon Gore charged". Daily News (New York). http://www.nydailynews.com/ny_local/2011/08/25/2011-08-25_giant_rat_killed_by_pitchfork_in_marcy_houses_is_believed_to_be_.html. 
5. ^ Conlon, Michael (2008-10-06). "Kids want an exotic pet? Ask your doctor first". Reuters. http://www.reuters.com/article/oddlyEnoughNews/idUSTRE49576S20081006. Retrieved 2008-10-06. 
6. ^ http://edocket.access.gpo.gov/2008/pdf/E8-20779.pdf

• Novak, R.M. and Paradiso, J.L.; Walkers Mammals of the World, Vol II. Johns Hopkins University Press, Baltimore, 1991.
• Perry, N. D., et al. 2006. "New invasive species in southern Florida: Gambian rat (Cricetomys gambianus)". Journal of Mammalogy, 87:262-264.
• Peterson, A. T., et al. 2006. "Native range ecology and invasive potential of Cricetomys in North America". Journal of Mammalogy, 87:427-432.
• [1] - a story from National Geographic News regarding the use of giant pouched rats and bees to detect land mines in Africa

External links

• "Apopo" mine clearance agency
• Hero Rat
• African and Gambian Giant Pouched Rats - Facts and Care
• EKF: African Giant Pouched Rat Forum