The Gambian pouched rat, 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. It is widespread in 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 2000 m. It is also an invasive species in Grassy Key in the Florida Keys.
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.
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.
In Africa, it is routinely eaten as bushmeat. It (and other mammals) are referred to by the pidgin name of "beef".
Invasive threat in Florida
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 USA, particularly the Southeast. Biologists say it would compete for food with native species, carry diseases, and damage the bird population by eating their eggs.
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. Several African species are believed to carry the disease.
In September 2008, the FDA and CDC have lifted the ban on pouched rats as pets in the United States. They are still illegal to import from outside the USA.
