Wombats

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Wombats

Wombats are thickset, bear-like, Australian marsupials (order Diprotodontia). They dig burrows, are about the size of a small dog, and have perpetually growing teeth (like placental rodents). Wombats are members of the family Vombatidae, which includes three species. The critically endangered Queensland or northern hairy-nosed wombat (Lasiorhinus krefftii ) is limited to a small area of Epping Forest National Park in central Queensland, where the surviving animals (about 100 individuals) live in burrows in an old riverbed. The southern hairy-nosed wombat (L. latifrons) lives in dry grass-lands of southern Australia, such as the Nullabor Plain along the Great Australia Bight. The hairy-nosed wombats have fine white hairs on a fairly large nose, while the nose of the common wombat (Vombatus ursinus) isleathery and bare. The common wombat lives in forests on mountainsides, and has characteristic, rounded ears.

Wombats can weigh more than 80 lb (40 kg) and can be 3 ft (1 m) long. They are gray or brownish gray, and are darker on the back than on the belly. The fur of the common wombat is coarse, while that of the hairy-nosed wombats is soft and silky. The feet of wombats have bare, leathery pads that withstand the energetic digging by their broad, flat, shovel-like claws (five on the front feet, four on the back).

In Australia and nearby islands, wombats occupy the ecological niche of a burrow-living plant-eater, similar to that of the woodchuck in North America. Wombats have chisel-like teeth that must grow continuously because they are eroded by constant chewing on coarse grasses and roots. Wombats are quick and efficient at digging, which they do by lying on their side and using their heavy-clawed front feet to dig and their hind feet to push the soil backward. Wombats often lie near the entrance to their burrow and bask in the sun, feeding at night.

Hairy-nosed wombats dig systems of interconnecting tunnels, while the common wombat is likely to inhabit a limited system of only two or three tunnels. Common wombats establish a territory of up to 60 acres (25 ha), but do not demand exclusivity, for it often overlaps with that of another wombat. Common wombats may even share the same burrow, though they occupy it at different times of day.

Wombats have a poorly developed cooling system, and if they get too hot they can die. They usually avoid high temperatures by retreating to their burrows, which provide cooler places in the summer and a warmer spot in winter. The hairy-nosed wombats rarely drink, getting all their water from the plants they eat. Their food is digested very slowly in order to get the most nourishment from it.

Wombats are solitary animals, except during the mating season, and then only if there is sufficient food available. Males fight for mating rights and females fight off males during courtship, so any pair that mates is usually bloody and scarred. After a gestation of only three or four weeks, a single offspring is born, which is carried in a rear-facing pouch. The wombat’s pouch is held closed by a strong muscle. As the tiny wombat grows and begins to move around, this pouch muscle relaxes, and the infant wombat may be seen peering out from between its mother’s hind legs. It takes at least five months for the eyes to open and the fur to grow in. The young wombat does not leave the pouch until it is about a year old. Wombats make amiable pets and have lived in captivity for over 25 years.