SAN BERNARDINO KANGAROO RAT } Dipodomys merriami parvus
DESCRIPTION: San Bernardino kangaroo rats have yellow to dusky brown fur above, with white undersides. Their long tails have dark brown stripes, and there is a dark line on each side of their noses. They measure approximately nine inches in length, more than half of which is their tail. Like all kangaroo rats, they have large hind feet on which they hop around, which also give them their name. San Bernardino kangaroo rats are distinguished from other species in that they have four toes instead of five on each hind foot.
HABITAT: San Bernardino kangaroo rats are found on the gentle slopes of alluvial fans, on flood plains, along washes, and on adjacent upland areas with soils containing sand, loam, and gravel deposited by rivers and streams. They also occupy areas where sandy soils are wind deposited. These soft soils allow kangaroo rats to dig shallow burrows and they support alluvial sage scrub, coastal sage scrub, and chaparral vegetation.
RANGE: The San Bernardino kangaroo rat was once a common resident of the San Bernardino Valley in Southern California’s San Bernardino County and in the San Jacinto River valley in Riverside County. The species’ range included 326,000 acres of alluvial scrub habitat in these areas. Critical habitat has been designated in the Etiwanda Fan, Lytle Creek, and Cajon Creek areas, along the Santa Ana River in San Bernardino County, and near the San Jacinto River and Bautista Creek in Riverside County.
MIGRATION: The San Bernardino kangaroo rat is nonmigratory.
BREEDING: Breeding occurs from January through November, peaking in late June. Following a one-month gestation period, female San Bernardino kangaroo rats give birth to one litter per year, averaging two to three young. Young rats are born and reared inside the burrow.
LIFE CYCLE: Kangaroo rats generally live two to five years.
FEEDING: San Bernardino kangaroo rats feed on seeds, grains, insects, and seasonally available green vegetation. They have pouches on the outsides of their cheeks that they use for carrying seeds back to their burrows. While kangaroo rats rely mostly on storing large quantities of seeds in tiny pit caches near their burrow entrances, insects have also been shown to constitute as much as half of their diet at certain times of the year. Kangaroo rats do not need to drink water, since they extract the moisture they need from their diet.
THREATS: Threats to the San Bernardino kangaroo rat include continued loss, degradation, and fragmentation of habitat due to sand and gravel mining, flood control projects, and urban development. Three of the largest blocks of remaining habitat for the species are actively mined for sand and gravel.
POPULATION TREND: Once considered common in San Bernardino and Riverside counties, the San Bernardino kangaroo rat had lost significant habitat by the 1930s. With continued habitat fragmentation and destruction, today nearly 95 percent of the kangaroo rat’s habitat has disappeared.