Giant Kangaroo Rat
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SpeU.S. Fish and Wildlife Service Giant Kangaroo Rat Dipodomys ingens vertical shaft with a circular opening The major units are fragmented into and no dirt apron and 2) larger, more more than 100 smaller populations, horizontally-opening shaft, usually many of which are isolated by wider than high with a well-worn several miles of barriers such as path leading from the mouth. steep terrain with plant communities Reproduction is influenced by unsuitable as habitat or by population density and availability agricultural, industrial, and urban of food. that offer no habitat for this species. Extant habitat is estimated to be Giant kangaroo rats are primarily 27,540 acres. CLASSIFICATION seed eaters. However, they also eat Endangered—April 1987 green plants and insects. They cache Within currently occupied habitat, ripening seed heads in small surface populations of giant kangaroo rats DESCRIPTION pits or large stacks on the surface studied since 1979 have expanded The giant kangaroo rat (Dipodomys over their burrow system. After and declined 6 to 10-fold with ingens) is the largest of more than 20 curing for several weeks, seeds are changing weather patterns. Density species in the genus Dipodomys. transported to underground larders. estimates range from 2.5 to 275 Giant kangaroo rats forage on the animals per acre. Changes in density The name is based on the fact that surface from around sunset to near generally coincide with rainfall and they are adapted for two-footed sunrise, with most activity taking herbaceous plant productivity; (bipedal) hopping like a kangaroo. place in the first two hours after however, seed caching behavior of They have large, flattened heads dark. Foraging activity is greatest in the species may offset this effect. with short necks. Large, fur-lined the spring as seeds of annual plants cheek pouches extend as deep ripen. Commonly consumed seeds THREATS pockets of skin along the sides if the include peppergrass (Lepidium spp.), Completion of federal and state head. Their hind limbs are large filaree (Erodium cicutarium), water projects resulted in rapid compared to the size of their Arabian grass (Schismus arabicus) cultivation and irrigation of giant forelimbs. Their tails are longer than and brome grasses (Bromus spp.). kangaroo rat habitat. Urban and their combined head and body industrial developments, petroleum length. The tails have a crest of long DISTRIBUTION and mineral exploration and hairs, terminating in a large tuft. The historical distribution of giant extraction, new energy and water Giant kangaroo rats are kangaroo rats encompassed a narrow conveyance facilities, and distinguished from the similar San band of gently sloping ground along construction of communication and Joaquin kangaroo rats (Dipodomys the western edge of California’s San transportation infrastructures nitratoides) by the number of toes on Joaquin Valley, with occasional continue to destroy habitat for giant their hind feet. Giant kangaroo rats colonies on steeper slopes and ridge kangaroo rats and increase the have five toes, San Joaquin kangaroo tops, from the base of the Tehachapi threats to the species by reducing rats have four. Adult giant kangaroo Mountains, Kern County, in the and further fragmenting populations. rats weigh from 4.6 to 6.4 ounces south, to near Los Banos, Merced In addition, use of rodenticide- (131 to 160 grams) and they are 12.2 County, in the north. Historical treated grain to control ground to 13.7 inches (311 to 348 habitat was estimated to have squirrels and kangaroo rats may have millimeters) long. included over 1.5 million acres. The contributed to the decline of giant population is currently fragmented kangaroo rats. Giant kangaroo rats prefer annual into six major geographic units. The grassland on gentle slopes of two units located in the southern San CRITICAL HABITAT: generally less than 10°, with friable, Joaquin Valley are: Kettleman Hills None sandy-loam soils. They develop and Western Kern County (Lokern, burrow systems with one to five or Elk Hills, McKittrick, Taft, and RECOVERY PLAN: more separate openings. There are Maricopa). September 1998 generally two types of burrows: 1) November 2016 .