Dassie Rat: Petromuridae

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DASSIE RAT: Petromuridae

PHYSICAL CHARACTERISTICS

Dassie rats look a lot like squirrels. Soft and silky hair covers their bodies, with the exception of the undersides, which are yellow and hairless. The hairs are joined together in groups of three or five. Their fur color is usually brown, gray, or buff, or a combination of those colors. These colors help them blend into the surrounding rocks in their habitat. This sort of camouflage helps keep birds from spotting them from above.

Dassie rats have blunt heads; big eyes; short, black, round ears; and long, black vibrissae, stiff hairs that can be found near the nostrils or other parts of the face in many mammals. The tail is shorter than the head and body length, and long hairs cover the end part of their tails. Their tails have soft joints, which allow the tail to break off at the base if a predator, animal that hunts it for food, grabs a dassie rat by the tail. The dassie rat can simply release its tail and escape, relatively unharmed.

Dassie rats' front feet have four toes with claws. The thumbs on the front feet are short. Their hind feet have five toes with short, curved claws. The hind feet also have thicker hairs that look like tiny combs and are probably used for grooming. The soles of their feet have round, naked pads that help them to move around in the rocky areas where they live. Their feet are narrow. The head and body length of males is 10.9 to 14.0 inches (27.9 to 36.0 centimeters) and the head and body length of females is 9.9 to 14.0 inches (25.3 to 35.8 centimeters). Males weigh 6.0 to 7.4 ounces (170 to 210 grams) while females weigh 8.8 to 9.2 ounces (250 to 261 grams). Their flexible ribs and flat skulls help them to flatten their bodies, and squeeze into small areas when necessary. This can be helpful when escaping from predators. The nipples on females are on their sides, rather on their undersides, so if they are squeezed into a small space, the young can still feed.

GEOGRAPHIC RANGE

Dassie rats can be found in the Southwest Arid Zone of Africa, from southwestern Angola to the central and western parts of Namibia to the northwestern Northern Cape Province in South Africa.

HABITAT

Dassie rats live in areas with a lot of rocks on hills or mountains. This environment allows them to find small areas between or under the rocks to crawl into in case of an attack by a predator. When examining living areas, dassie rats will choose an area with good shelter over an area with good plant life. The rocky shelters that they choose include lookout areas and sunbathing platforms. They make sure to choose shelters that have protecting rocks over the sunbathing platforms as a defense against birds of prey that may try to attack while they are sunbathing. In addition, feeding areas are near their shelters, so they do not have to travel long distances.

DIET

Dassie rats are herbivores, plant-eating animals. They eat leaves, berries, seeds, grasses, twigs, and shrubs. They look for this food on the ground or in bushes, and take it back to their shelters. They may use grasses and leaves to build a nest in the shelter. Dassie rats can regurgitate (re-GER-jih-tate), throw up partially digested food, into their mouths where they chew it again and then swallow it. They are also coprophagous (kuh-PRAH-fuh-gus), which means that they eat their own pellets, or dung, for additional nutrients. They do not usually drink water, but get all the water they need from their food instead.

BEHAVIOR AND REPRODUCTION

Dassie rats are active during the daytime, especially during the early morning and the late afternoon. They sunbathe under rocks that shelter them from possible attacks by birds. They often urinate in one spot, which makes the rocks at this spot become white due to stains from the urine. A dassie rat may live alone, with another dassie rat, or in a group. However, they only travel alone or with one other dassie rat.

When a predator attacks, dassie rats squeeze into a crack or other small area, quickly escape by jumping on rocks, or let out a warning whistling call to show that they are scared. Dassie rats are able to squeeze into very small cracks that most other animals would not be able to enter.

The dassie rat mating season is from November to December. Females give birth to one or two babies once a year, when the raining season is just beginning. The young are born almost fully developed.

DASSIE RATS AND PEOPLE

Dassie rats do not have any special relationship with humans.

CONSERVATION STATUS

Dassie rats are not listed as threatened by The World Conservation Union (IUCN), but there is only a small population and they are not present in a large number of areas.