Giant kangaroo rat  (Dipodomys ingens)

Classified as Critically Endangered (CR) on the IUCN Red List 2007 (1).

The giant kangaroo rat is the largest of more than 20 species of kangaroo rats, which are small rodents that (as their name would suggest) move by hopping on their back legs. The front limbs are reduced and used only for digging, whist the hind limbs are long and powerful and the exceptionally long tail is used for balance (4). The hind legs can propel an individual in leaps of over 2 metres when escaping from predators (2). As with other kangaroo rats, this species has large eyes, small rounded ears and a somewhat rounded body (5). The fur is buff-coloured, and it has a white belly and a white stripe across the hindquarters. The tufted tail is dark but has white lines along either side (5).

Endemic to the San Joaquin Valley in California, USA (1).

Giant kangaroo rats are found in dry areas that receive less than 15 centimetres of rainfall each year, in well-drained sandy soils that are sparsely populated by annual grassland (2) (3).

These nocturnal animals hide in their burrows during the heat of the day, plugging the burrow entrance with loose soil and only emerging at night (2) (6). They are solitary and territorial, advertising their territory with a loud drumming produced by the thumping of the hind feet (2). Burrows tend to be fairly shallow and contain many connected enlarged chambers; one that acts as a nest and the rest used to store food (7). Kangaroo rats feed on seeds, vegetation and insects, storing a cache of seeds to see them through periods of drought (1). In years of good rainfall, a female may give birth to up to three litters and individuals born that year may themselves begin breeding when only 12 to 13 weeks old (2).

Population numbers of the giant kangaroo rat plummeted during the 20th Century (1), mainly as a result of habitat loss as desert areas were converted to agriculture (7). Over 95 percent of the former range of this species has been lost due to a combination of overgrazing, cultivation, mining operations and the introduction exotic plants (1).

This species is listed as Endangered by the California Fish and Game Commission and the United States Fish and Wildlife Service (1). A Recovery Plan has been developed in an effort to secure the future survival of this species (8), and populations are protected within the Carrizo Plan Natural Heritage Reserve and a number of Federal lands (1).

For more information on the giant kangaroo rat see:

• U.S. Fish and Wildlife Service:
  http://ecos.fws.gov/species_profile/servlet/gov.doi.species_profile.servlets.SpeciesProfile?spcode=A08P
• California Bureau of Land Management:
  http://www.blm.gov/ca/forms/wildlife/details.php?metode=serial_number&search=2603&detaillabelc=Giant%20Kangaroo%20Rat&detaillabels=Dipodomys%20ingens
• Smithsonian National Museum of Natural History:
  http://www.mnh.si.edu/mna/image_info.cfm?species_id=75

Authenticated (18/06/08) by Dr. David J. Hafner, Chair and Curator, Biosciences Department, New Mexico Museum of Natural History.
http://www.nmnaturalhistory.org

• Endemic: a species or taxonomic group that is only found in one particular country or geographic area.
• Nocturnal: active at night.

1. IUCN Red List (June, 2008)
   http://www.iucnredlist.org
2. Endangered Species Recovery Program, California (April, 2003)
   http://arnica.csustan.edu/esrpp/gkrprofl.htm
3. Williams, D.F., Byrne, S. and Rado, T.A. (1992) Endangered and Sensitive Species of the San Joaquin Valley, California.California Energy Commission, California.
4. Macdonald, D. (2001) The New Encyclopedia of Mammals.Oxford University Press, Oxford.
5. Desert USA (April, 2003)
   http://www.desertusa.com/aug96/du_krat.html
6. Hafner, D.J. (2008) Pers. comm.
7. California Bureau of Land Management (April, 2003)
   http://www.blm.gov/ca/forms/wildlife/details.php?metode=serial_number&search=2603&detaillabelc=Giant%20Kangaroo%20Rat&detaillabels=Dipodomys%20ingens
8. U.S. Fish and Wildlife Service (April, 2003)
   http://ecos.fws.gov/species_profile/servlet/gov.doi.species_profile.servlets.SpeciesProfile?spcode=A08P