Merriam’s Kangaroo Rat, Dipodomys merriami
Merriam’s kangaroo rat, named after Clinton Hart Merriam , is a small rodent (about fourteen inches long) that has a pouch lined with fur that serves as food storage. These rats use their cheek pouches for convenient food storage when foraging. The kangaroo rat is named so because of their extremely long feet, similar to those of an actual kangaroo. Like a kangaroo, this rat will hop or jump as a means of travel, instead of running or scurrying. Because of this, the kangaroo rat has a very long tail meant to help counterbalance the motions of hopping or jumping. A tuft on the tip of the tail is also thought to help with balance, giving drag in order to keep the rat stable. The fur on the kangaroo rat is usually tan or light brown. Mirriam’s kangaroo rats, unlike other kangaroo rats, have four toes on each hind foot.
Merriam’s kangaroo rat, or Dipodomys merriami, lives in Baja, California, the southwestern United States, and Mexico. They can also be found in washes and desert east of Volcan, the Palomar Mountains, and Lugana. These nocturnal rodents live individually in mazes of burrows, making sure that there are multiple entrances at the base of desert shrubs around the middle of their territory. The males and females live separately, each defending their space from other kangaroo rats in order to protect their food sources, which are often scarce.
Being granivorous , the diet of the kangaroo rat consists mostly of grassland and desert plant seeds. The kangaroo rat rarely drinks water, instead metabolizing water through the moisture content of their food. Losing water by the evaporation process through gas exchange has caused the kangaroo rat to adapt this form of water consumption. Because they spend so much time in their burrows, moisture is transferred from their bodies into the air, and then into the seeds they eat.
Merriam’s Kangaroo Rat is active at night, going out of its burrow to forage for food, defend its territory, or find a mate. If there is a lot of moonlight, or a full moon, the rat will stay outside for only two or less hours in order to avoid predation and heat. After the kangaroo rat is done hopping about its territory collecting food, it will return to its burrows and store the gathered food, eating some immediately. During the day, it will stay in its cool burrows to avoid heat, sometimes sealing entrances to keep out the heat.
Predators of this rat include many desert animals such as snakes, owls, badgers, coyotes, and foxes. Mirriam’s kangaroo rat can produce up to three litters per year, with up to four pups in each litter. The weaning process occurs between twenty-two and thirty-three days after birth.
Although humans have not caused problems for the Merriam’s kangaroo rat in general, one subspecies known as the San Bernardino Kangaroo Rat has been affected greatly. This kangaroo rat, located in southern California, was listed as endangered by the United States Fish and Wild Life Services in 1998 due to issues including urbanization and the building of dams.
Image Caption: A female Dipodomys merriami, upon release to the wild after a brief period of observation. Capture was conducted as part of a biological survey for the State of California near the Salton Sea. Credit: Baiken/Wikipedia(CC BY-SA 3.0)