Hyraxes: Hyracoidea

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HYRAXES: Hyracoidea


SOUTHERN TREE HYRAX (Dendrohyrax arboreus): SPECIES ACCOUNTS
ROCK HYRAX (Procavia capensis): SPECIES ACCOUNTS

PHYSICAL CHARACTERISTICS

Hyraxes are herbivores, plant eaters, that resemble guinea pigs. They have short legs, a stubby tail, and round ears. There is no average size, as the species vary greatly across Africa, but the growth of the hyrax seems to be directly linked to precipitation, or rainfall—the largest hyraxes are in the areas with the most rainfall.

The feet have pads on them that contain sweat glands. The hyrax sweats as it runs, which help its feet pads grip, making it easier to climb. The feet are flexible and can turn upwards. The front foot has four toes and the hind foot has three toes. All toes have flat nails except for the second toe of the hind foot. This toe sports a long, curved claw used for grooming.

All hyraxes have fur, but the length of it depends on the climate in which they live. The colder the temperature, the longer the fur. Coat color ranges from light to dark, and may be brown, white, or gray. The bulging eyes are framed by bushy white eyebrows. The head is flat on top, and the muzzle, nose and mouth area, is shaped like a skunk's muzzle.

GEOGRAPHIC RANGE

Hyraxes live mainly in Africa. The rock hyrax has been seen from Lebanon to Saudi Arabia.

HABITAT

Hyraxes easily adapt to their surroundings and can work with any kind of shelter so long as it provides the necessary protection from weather and predators, animals that hunt them for food.

Each species is distinct in terms of where it lives. The bush and rock hyraxes need mountain cliffs and an abundance of rocks for refuge. Tree hyraxes prefer moist forests and savannas, a tropical environment that contains trees and shrubs and has a dry season. At higher elevations they can survive among rocks.

DIET

The hyrax eats mostly twigs, fruit, and bark as well as leaves, but it also feeds on lizard and bird eggs. Because their food is plant based, hyraxes can go for long periods of time without water, getting the moisture they need from the plants they eat.

BEHAVIOR AND REPRODUCTION

Rock and bush hyraxes are active during daylight hours and tend to live in groups whereas tree hyraxes are nocturnal, active at night, and prefer to live on their own. The social unit of the rock and bush hyraxes includes one adult male and about seventeen adult females, with their young. Though solitary, tree hyraxes have been found in groups of two or three. In this group, too, there is a hierarchy, rank structure, and the male is at the top.

Hyraxes mate once a year. Gestation, pregnancy, lasts twenty-six to thirty weeks, and the number of babies per female ranges from one to four. Mothers suckle only their own babies, and the young stop nursing anywhere from one to five months. Both sexes are ready to mate between sixteen and seventeen months of age. At this time, females join the adult female group while males take off on their own. Adult females live longer than adult males and may reach eleven years or more.

Young hyraxes are playful, with normal behavior including biting, climbing, chasing, and fighting.

A PATCHWORK MAMMAL

Although the hyrax resembles a rabbit or guinea pig, it is actually closely related to elephants and other hoofed animals. Its anatomy is like an elephant and a horse. Its brain is like an elephant's while the stomach is like a horse's. It has a skeleton similar to that of a rhinoceros, and its upper incisors, chisel-shaped teeth at the front of the mouth, look like those found on rodents. The upper cheek teeth are like those of a rhinoceros and the lower cheek teeth are similar to those of a hippopotamus.

HYRAXES AND PEOPLE

Some African people hunt hyraxes for food and skin. The tree hyrax is harvested to be used in medicine. Deep coughs are relieved by drinking the ash of burnt hairs mixed with honey or water. Also, some tribes wrap newborn babies in hyrax skin to ensure health and vitality.

CONSERVATION STATUS

Three hyrax species are listed as Vulnerable, facing a high risk of extinction in the wild. Because these three species are found primarily in the African forests, their status is probably the result of habitat destruction, as well as being hunted for food and their fur. No other species has been given special status.

SOUTHERN TREE HYRAX (Dendrohyrax arboreus): SPECIES ACCOUNTS

Physical characteristics: From head to hind end, the southern tree hyrax is anywhere from 12.5 to 24 inches (32 to 60 centimeters) long and weighs 3.7 to 9.9 pounds (1.7 to 4.5 kilograms). The soft coat is made of long, dark brown hair.


Geographic range: Southern tree hyraxes are distributed throughout South Africa.


Habitat: They live in evergreen forests up to 13,500 feet (4,500 meters), and among boulders in the Ruwenzori Mountains.

Diet: Tree hyraxes eat leaves, twigs, and fruit year-round.

Behavior and reproduction: Southern tree hyraxes spend daylight hours nestled in the hollows of trees and venture out only in the safety of the night. More often heard than seen, the male tree hyrax emits shrill shrieks in order to claim his territory, and as an effort to keep in contact with his family throughout the night.

Southern tree hyraxes are very good climbers but are awkward on the ground.

Not much is known about the reproductive behavior and cycle of the tree hyrax. Gestation lasts from 220 to 240 days, and each pregnancy yields one to two babies. Babies are competent tree climbers by the end of their first day. Southern tree hyraxes live at least ten years.


Southern tree hyraxes and people: Some African people eat the southern tree hyrax and use the skin to make rugs and clothing. They are also used as medicine. Southern tree hyraxes play important roles in African spiritual traditions as well.


Conservation status: Southern tree hyraxes are not threatened. ∎

ROCK HYRAX (Procavia capensis): SPECIES ACCOUNTS

Physical characteristics: Rock hyraxes are 17 to 21 inches (44 to 54 centimeters) long and weigh 4 to 12 pounds (1.8 to 5.4 kilograms). Their fur is light to dark brown.


Geographic range: Rock hyraxes are found from southwest to northeast Africa, Sinai to Lebanon, and the southeast Arabian Peninsula.


Habitat: Rock hyraxes prefer mountain cliffs and rocky outcrops or boulders. They live in the crevices of rocks.


Diet: Rock hyraxes eat quickly, with some members of the colony keeping watch for predators while the rest feed on leaves, fruit, lizard and bird eggs, and long grasses. When they eat, rock hyraxes take a mouthful of food, then quickly check out their surroundings. Because their greatest predators are birds of prey, the rock hyrax must be able to look into the sky to avoid being swooped down upon and eaten. For this reason, they have a protective film over their pupils that allows them to look directly into the sun without damaging their eyes.


Behavior and reproduction: Rock hyraxes are social creatures and live in colonies up to fifty members. As many as twenty-five hyraxes can share one den. Unlike tree hyraxes, rock hyraxes are busy during daylight hours, but since they are unable to regulate their body temperature, they will not be found foraging during very hot or very cold temperatures.

The social unit is comprised of one adult male, up to seventeen females, and their young. Although several groups may live in one area, the head male will defend his territory from other males. Predators of the rock hyrax include leopards, snakes, and birds of prey.

Rock hyraxes have more than one mate, but they give birth just once a year. Pregnancy results in one to four babies per female after a gestation period of 212 to 240 days. Once a baby reaches one to five months of age, it is weaned, taken off its mother's milk. By sixteen or seventeen months, the rock hyrax is ready to breed.

Rock hyraxes live anywhere between nine and twelve years, with females living longer than males.


Rock hyraxes and people: Some African tribes hunt the rock hyrax for food, and it is mentioned numerous times in the Bible as "conie," which means "rabbit."


Conservation status: Rock hyraxes are not threatened. ∎

FOR MORE INFORMATION

Books:

Mostue, Trude. Wild About Animals. London: Madcap, 1999.

Ricciuti, Edward R., Jenny Tesar, and Bruce Glassman, eds. What on Earth is a Hyrax? Detroit: Gale Group, 1996.

Periodicals:

Slattery, Derek M. "Kenya—the Rock and Tree Hyrax or Dassie." PSA Journal (September 2003): 29–31.

Web sites:

"Hyrax." Out to Africa. http://www.outtoafrica.nl/animals/enghyrax.html?zenden=2&subsoort_id=4&bestemming_id=1 (accessed on July 9, 2004).

"Hyrax." Science Daily. http://www.sciencedaily.com/encyclopedia/hyrax (accessed on July 9, 2004).

"The Hyrax: More Elephant than Rodent." BBC Science & Nature: Animals. http://www.bbc.co.uk/nature/animals/features/155index.shtml (accessed on July 9, 2004).

"Rock Hyrax." Nature Niche. http://natureniche.tripod.com/hyrax.html (accessed on July 9, 2004).

"Rock Hyrax." Wildlife Safari Info. http://www.wildlifesafari.info/hyrax_rock.html (accessed on July 9, 2004).

World Wildlife Fund. http://www.panda.org/ (accessed on July 9, 2004).