Overview
The giant kangaroo rat is the largest member of the family that includes kangaroo rats, kangaroo mice and pocket mice. Named for its unique two-footed hopping movements, the giant kangaroo rat lives in grassland areas generally along the western edge of California's San Joaquin Valley from Fresno County in the north to Kern County in the south and the Carrizo Plain and Cuyama Valley in San Luis Obispo County. They were listed as endangered in April 1987.
The giant kangaroo rat has a large, flattened head and a short neck. Large, fur-lined cheek pouches are used to store and carry seeds found while foraging. Their tails are longer than their combined head and body length. The tails have a crest of long hairs, terminating in a large tuft. Their long, strong legs enable them to quickly hop away from predators such as snakes.
The giant kangaroo rat faces several threats that have the potential to reduce populations. These threats include:
- Habitat conversion and fragmentation due to agricultural use, urban and industrial developments, oil and mineral exploration and extraction, solar energy, water conveyance facilities, and construction of communication and transportation infrastructure
- Rodenticide use associated with agricultural operations, including legal and illegal cannabis cultivation
Scientific Name
Identification Numbers
Characteristics
Habitat
The giant kangaroo rat prefers annual grassland on gentle slopes with sandy soils. However, most remaining populations are on poorer, marginal habitats which include shrub communities on a variety of soil types and steeper slopes.
Giant kangaroo rats develop burrow systems, called precincts, with one to five or more separate openings. There are generally two types of burrows: 1) a vertical shaft with a circular opening and no dirt apron, and 2) a larger, more horizontally opening shaft—usually wider than high—with a well-worn path leading to the burrow.
The historical distribution of giant kangaroo rats encompassed a narrow band of gently sloping ground along the western edge of the San Joaquin Valley, with occasional colonies on steeper slopes and ridge tops, from Merced County in the north to Kern County in the south and the Carrizo Plain and Cuyama Valley in San Luis Obispo County. Historical habitat was estimated to be over 1.5 million acres.
Today, the species is currently fragmented into six major geographic units: (1) Ciervo-Panoche in western Fresno and eastern San Benito counties; (2) Kettleman Hills in southwestern Kings County; (3) San Juan Creek Valley, east of San Luis Obispo County; (4) the Lokern area, Elk Hills, Taft, and Maricopa in western Kern County; (5) the Carrizo Plain in eastern San Luis Obispo County; and (6) the Cuyama Valley along and east of the Santa Barbara-San Luis Obispo County line.
Land on which the natural dominant plant forms are grasses and forbs.
Arid land with usually sparse vegetation.
Environments influenced by humans in a less substantial way than cities. This can include agriculture, silvaculture, aquaculture, etc.
Food
Giant kangaroo rats are primarily seed eaters; however, they also eat green plants and insects.
Giant kangaroo rats forage above ground from sunset to near sunrise, with most activity taking place in the first two hours after dark. Foraging activity is greatest in the spring as seeds of annual plants ripen. Commonly consumed seeds include peppergrass (Lepidium spp.), filaree (Erodium cicutarium), Arabian grass (Schismus arabicus) and brome grasses (Bromus spp.).
The giant kangaroo rat is excellent at storing food for the winter months. They forage for seeds and then place the ripening seed heads in small pits or large stacks on the surface over their burrow system. After curing for several weeks, they move the seeds to underground storage areas.
Life Cycle
Reproduction is influenced by population density, availability of food and environmental conditions. During non-drought years, females can have one to three litters a year with one to four young per litter after approximately 30 days of gestation. Breeding generally occurs in the winter but can extend into the spring and summer months. Their average lifespan is not well documented but is likely around 2 years. Some individuals have been known to live for 6 years.
Physical Characteristics
Giant kangaroo rats have large, flattened heads and short necks. Large, fur-lined cheek pouches extend as deep pockets of skin along the sides if the head, which they fill with seeds as they forage. Their hind limbs are large compared to the size of their forelimbs. These strong rear legs enable the species to hop from place to place and help them quickly get out of the way of predators, such as snakes. Their tails are longer than their combined head and body length. The tails have a crest of long hairs, terminating in a large tuft.
Giant kangaroo rats are distinguished from the similar San Joaquin kangaroo rats (Dipodomys nitratoides) by the number of toes on their hind feet; giant kangaroo rats have five toes, San Joaquin kangaroo rats have four. Thie giant kangaroo rat can be distinguished from the more common Heermann’s kangaroo rat (Dipodomys heermanni) based on a greater hind foot length and body size.
Size and Shape
- Weight: Adult giant kangaroo rats weigh 3.5 to 6.7 ounces (100 to 190 grams)
- Total Length: 12.2 to 13.7 inches (311 to 348 millimeters)
Timeline
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