Mountain Pocket Rats
| Mountain Pocket Rats | ||||||||||||
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Mountain Pocket Rat ( Thomomys bottae ) |
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| Scientific name | ||||||||||||
| Thomomys | ||||||||||||
| Wied-Neuwied , 1839 |
Mountain pocket rats ( Thomomys ) are a genus of pocket rats with nine species that occur in western North America .
Types and distribution
The genus includes the following species:
- Mountain pocket rat ( Thomomys bottae , Eydoux & Gervais, 1836), southwestern United States and northern Mexico .
- Camas pocket rat ( Thomomys bulbivorus , Richardson, 1829), in the valley of the Willamette River and its tributaries.
- Wyoming pocket rat ( Thomomys clusius Coues, 1875), State of Wyoming .
- Idaho pocket rat ( Thomomys idahoensis Merriam, 1901), Idaho and adjacent states.
- Mazama Pocket Rat ( Thomomys mazama , Merriam, 1897), Washington State to Northern California .
- Sierra pocket rat ( Thomomys monticola , JA Allen, 1893), northwestern California and neighboring areas of Nevada .
- Northern pocket rat ( Thomomys talpoides Richardson, 1828), Great Plains , Rocky Mountains and other mountain ranges in western Canada and the USA.
- Townsend pocket rat ( Thomomys townsendii Bachman, 1839), several dispersed populations in Idaho, Oregon , Nevada, and California.
- Dwarf pocket rat ( Thomomys umbrinus Richardson, 1829), from Arizona and New Mexico to central Mexico.
features
The types are similar to the other pocket rats in physique. They reach a head-trunk length of 11.5 to 30.5 cm, a tail length of 4 to 9.5 cm and a weight of 45 to 545 g. The color of the short and soft fur can vary greatly between the individual specimens; there are black, brown, gray and white tones, with the underside only appearing slightly lighter. The tail is only sparsely covered with hair at the base and bare at the tip. The species have long claws on the front paws with which they dig in the earth. They usually use the incisors on harder ground. Characteristic for the genus is the lack of grooves on the front of the incisors. This feature occurs only in a few other pocket rats.
Way of life
These pocket rats can dig in different types of soil . Some species reach rocky mountain ridges that are 4000 meters above sea level. Deserts, prairies , open forests and meadows serve as habitats .
The animals create complex tunnel systems, the deepest areas of which can be 3 meters below the surface of the earth. Within the system there are several chambers with a diameter of 20 to 25 cm as living rooms or storage space. In addition to their own burrow, passages are dug when searching for food, which are usually 13 to 46 cm long. In winter, the burrows can also lie above the ground within the snow cover.
Mountain pocket rats are active at different times of the day and all year round. They mainly eat roots and tubers, which are completed with various above-ground parts of the plant. The latter are usually collected at night or pulled into the tunnel by the roots. With their cheek pouches , the animals can carry large amounts of food into the storage rooms. They completely cover their fluid requirements with solid food.
Outside the breeding season, individuals avoid each other. If they meet, there will be fierce fighting. Mating takes place in the female's den after the cold season and depending on the species and distribution area. After about 19 days of gestation , 1 to 10 young animals are born. The average litter size varies between species. The young must leave the mother's den after about two months. They are fully grown after 5 to 6 months and will be able to reproduce next spring. Many specimens do not survive the first year. They fall prey to owls , silver badgers , coyotes , foxes and other predators or freeze to death in winter. Individual individuals, on the other hand, lived to be up to four years old.
Mountain pocket rats and humans
With their burrowing way of life, the species create better aeration and mixing of the soil, making it more suitable for further use. On the other hand, the combination of overgrazing by farm animals and the occurrence of mountain pocket rats can lead to an area becoming unusable more quickly. When the rodents eat potatoes or gnaw the roots of young trees, they are fought as pests.
All species are listed as Least Concern by the IUCN .
swell
- Ronald M. Nowak: Walker's Mammals of the World. Volume 2. 6th edition. Johns Hopkins University Press, Baltimore MD et al. 1999, pp. 1311-1312, ISBN 0-8018-5789-9 .
- Wilson & Reeder (Eds.): Mammal Species of the World . 3. Edition. Johns Hopkins University Press, Baltimore 2005, ISBN 0-8018-8221-4 (English, Thomomys ).
- Thomomys on the2015 IUCN Red List of Threatened Species. Accessed January 10, 2016.
