Wombats: Vombatidae

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WOMBATS: Vombatidae

COMMON WOMBAT (Vombatus ursinus): SPECIES ACCOUNT

PHYSICAL CHARACTERISTICS

Wombats are stout, stocky burrowing marsupials with powerful forearms and sharp claws for digging. A marsupial is a mammal that does not have a well-developed placenta and gives birth to immature and underdeveloped young, which it then continues to nurture, often in a pouch, until the young are able to fend for themselves. Wombats are about 3.3 feet (1 meter) long and weigh from about 55 to 88 pounds (25 to 40 kilograms). Their fur varies from gray to brown.

All three species of wombat look similar. They have large heads, small ears and eyes, and short, strong necks. They have front teeth, incisors, that continue to grow throughout their life and must be worn down by the food they eat. The main physical difference among the three species is the presence or absence of hair on their nose. Male and female wombats look similar. The female has a backward-opening pouch in which she carries her young. In the past, fossils show that there were as many as nine species of wombat, including one that weighed 440 pounds (200 kilograms). Today the closest living relative of the wombat is the koala.

GEOGRAPHIC RANGE

Wombats live in southeastern Australia. The common wombat is fairly widespread and can be found in parts of New South Wales, Victoria, South Australia, and Tasmania. The northern hairy-nosed wombat lives only in one place in Queensland, and the southern hairy-nosed wombat lives in a small area along the south central coast of Australia.

HABITAT

Wombats live under the ground in open grassland, open woodlands, and dry, shrubby, forested areas. They prefer areas where the ground is soft enough to dig extensive burrows.

DIET

Wombats are herbivores, and eat only plants. They mainly eat native grasses, but will also eat roots, bark, and moss. They graze above ground at night and may travel up to 1.8 miles (3 kilometers) each night looking for food. Because the food they eat is high in fiber and hard to digest, it is held in their digestive system for up to seventy hours in order to break down the fiber and release the nutrients.

BEHAVIOR AND REPRODUCTION

Wombats are nocturnal, active at night. During the day they rest in their burrows, which can be 100 feet (30 meters) long and 6 to 7 feet (1.8 to 2.1 meters) deep. The burrows usually have several entrances and side branches and are large enough for a small adult to fit into them. The southern hairy-nosed wombat builds particularly complex tunnel systems that it may share with other wombats.

Even when they share tunnels, wombats feed alone and are territorial about their feeding grounds. They mark their personal areas with scent and droppings, and act aggressively toward other wombats that move into their territory. Usually, male animals must leave their birth area to find a new territory, but it is the female wombats that are driven out of their birth area and are forced to find new feeding grounds when they mature.

THE WOMBAT BOY

In 1960 Peter "PJ" Nicholson was a fifteen year old student at Timbertops, a rural Australian boarding school. PJ became fascinated with wombats. For a year, he sneaked out at night and crawled down wombat burrows. He was patient, visiting often and letting the wombats become comfortable with him. Eventually he traveled 70 feet (21 meters) inside the tunnels to the wombat nests. The measurements and maps that he made of the tunnels were published, and his information is still used by scientists. PJ Nicholson later earned a degree in economics, although he never lost his interest in wildlife.

Wombats, like all marsupial mammals, have short pregnancies and give birth to a single tiny, underdeveloped newborn. Pregnancy lasts only about twenty-two days. After birth, the young crawl to the mother's pouch and remain there attached to a teat, nipple, for six to nine months. After leaving the pouch, the young wombat stays with the mother for another year, gradually nursing less and eating more plant material, until it is finally weaned, not nursing, and independent. Wombats become capable of reproducing when they are two years old. They live more than five years in the wild and have lived up to seventeen years in captivity.

WOMBATS AND PEOPLE

Although wombats have no commercial value, they are considered a symbol of Australia. There are active foster care programs for raising orphaned wombats. However, farmers sometimes see wombats as pests, because their tunnels allow rabbits to pass under rabbit fences and destroy crops. For this reason they are sometimes shot.

CONSERVATION STATUS

Development in Australia has reduced and fragmented wombat habitat. In addition, dogs, dingoes (wild dogs), and automobiles are the other main threats to wombats. The northern hairy-nosed wombat is Critically Endangered, facing an extremely high risk of extinction in the wild. It lives in only one place, the Epping National Forest in Queensland, where it is off-limits to visitors. As few as 100 individuals may remain in the wild. The other two wombat species are not threatened.

COMMON WOMBAT (Vombatus ursinus): SPECIES ACCOUNT

Physical characteristics: Common wombats have stocky bodies that ranges from 35 to 45 inches (90 to 115 centimeters) and short, stumpy tails only about 1 inch (2.5 centimeters) long. They can weigh anywhere from 48.5 to 86 pounds (22 to 39 kilograms). Their short, coarse fur is black, brown, or gray, and they are distinguished from the hairy-nosed wombats by their bare muzzles.

Geographic range: Common wombats are found in southeastern Australia, Tasmania, and Flinders Island.

Habitat: Common wombats prefer open forests and woodlands with well-drained soil that is easy to dig.

Diet: These animals are herbivores and eat mainly native grasses and roots.

Behavior and reproduction: Common wombats live alone and are active at night. They do not often share their burrows with other wombats. They have a home range that usually contains several burrows.

The young can be born at any time of the year. They remain in their mother's pouch for about six months, and continue to stay with the mother outside the pouch for about another twelve months. Males do not help raise their offspring.

Common wombats and people: In some areas, this wombat is considered a pest by farmers and is shot or poisoned.

Conservation status: These animals are not threatened, even though their habitat has been reduced by development. In many parts of their range, this animal is common. ∎