Tuesday, July 18, 2017

A Moment with Nature: Kangaroo Rat


From the Western Heritage Nature Trail System


Featuring: Kangaroo Rat (Dipodomys deserti)




The Desert Kangaroo rat is one of 22 species of kangaroo rats that can be found in the North American arid southwest. New Mexico is home to 3 of the kangaroo rats. These small rats inhabit the lowest, hottest, and most arid regions of our seven western states, they can be found in northern Mexico and up to the Canadian provinces too.

Habitat:
The Desert Kangaroo rat prefers arid climates with sparse vegetation covering sandy ground. Desert Kangaroo rats burrow into the sand dunes, they are rarely found on hard or gravelly soils These rats are one of the few animals to establish colonies and exist in shifting sand dunes. A colony will effectively dig 6 to 12 burrows with in the dunes, complete with entrance and escape holes, cache rooms for food supply storage, nesting areas and even a nursery for rearing the neonates.

Appearance:
A Desert Kangaroo rat size ranges from 3 to 6 inches. They have an extremely long tail up to 7 inches long and it tapers with white-tipped guard hairs along the top to the tip end. These rats have small forelimbs and long, strong hind legs which modified for jumping, hence the name “Kangaroo” rat. The legs have long hairs aiding in their defense tactics. Desert Kangaroo rats have the thickest hair in their genus that is a pale brown on their backs with scatterings of black hairs along the spine. They have indistinct white markings above their eyes, on their feet and underbelly. 

Breeding Season:
Desert Kangaroo rats mate in the spring coinciding with spring rains that bring on an abundance of food sources. The female Kangaroo rat is the ‘hussy’ of the rat-world, she will mate with several males. Once she has conceived this rat produces a fetal plug and no other males can breed with her. Droughts diminish the breeding populations considerably. The female can produce 2 litters a year and have 1 to 6 neonates (babies). Her gestation period is 29-32 days. The young are born head-first and the mother assists in delivery by pulling on the fetal membrane during the birthing process. Baby Desert kangaroo rats can breed at two month of age. Their life-span is 3 to 5 years.


Communication:
Desert Kangaroo rats have a keen sense of smell, extraordinary hearing, and excellent night vision. They are not vocal, but can make soft squeaks. All Kangaroo rats are “drummers”, they thump the ground with their powerful hind legs to make a loud noise when their burrow entrances are disturbed and danger is present. Drumming of their hind feet also signals the colony that food sources are found.

Food:
Desert Kangaroo rat diets comprise primarily dried seeds, nuts, leaves of certain food plants, mesquite bean pods. They can and will at times eat an insect, but mostly plant matter. They have fur-lined cheek pouches in which stuff the food sources and transport back to the colony and store in underground food chambers. They normally do not drink water, as their unique bodies metabolizes moisture from their food.

Predation Action:
All kangaroo rats are nocturnal creatures. During the day their colony entrances are packed with sand to keep predators out. These little rats with the unique hind legs sever in two purposes, one for travelling and the other for fear-flight response when a predator is hunting them down. Their hind legs can propel these rats 6 to 8 feet in a rapid response to escape.

Another unusual action of these little rats, is they can be staunch and aggressive for their size. I mentioned above about the long hairs on their hind leg to feet. When disturbed by a predator they will turn around and face the predator and begin kicking sand into the enemy’s eyes. This gives them a possible chance of escape by boing-boing off into a safe zone away from the predator.

Animals that do feed on the kangaroo rats are, hawks, owls, bobcats, skunks, coyotes, foxes and snakes.

So, when you are on the Western Heritage Nature Trail you won’t see a live Desert Kangaroo rat, but you can see a bronzed replica of this little amazing rat of the Lea County sand dunes. On any give moon-lit night, travel down some of the back county roads of Lea County’s oil patch and you will see the Desert Kangaroo rats hopping across the road in your headlights. 


This bronzed Desert Kangaroo rat is off to the South side as your walk to the front entrance of the museum. Oh, by the way, you may see a large Pack rat and some Cotton rats that are inhabiting the biomes in the trail system as you walk along.