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The uncommon wombat

The underground lifestyle and nocturnal habits of wombats mean they can be hard to catch sight of, but this time of year provides a great opportunity to spot the world's largest burrowing herbivore.

Wombats have a reputation for being muddle-headed, plodding and dozy. But this doziness actually masks a consummate skill for energy conservation — they have exceptionally slow metabolisms and very low water needs.

Their metabolism has been described as almost reptilian, allowing them to convert 'grass to wombat' three times more efficiently than kangaroos. The stable temperature in their underground burrows is particularly important, helping them to manage their energy usage efficiently throughout the year.

This means that the cooler months, from May to October, are the best time to spot wombats in the daytime.

"During the winter, they'll often come up in the afternoons or mornings and have a feed, then head back down and stay in their burrows through the night, because it's just too cold and they can conserve energy," explains Barbara Triggs, a wombat expert since 1972. "In summer they often won't emerge until midnight."

By letting body temperature drop while they are snoozing, wombats don't need to consume as much food as other mammals. Their diet is almost exclusively grass, with a nibble of moss, mushrooms or fungus as an occasional treat. They tend to only dig up roots and tubers in dry times.

And their efficiency extends to water usage. Wombats are amongst the lowest water consumers of any mammal on earth, needing only 20 per cent of what a sheep requires. They conserve water in all aspects of their lives, including excreting droppings four times drier than a camel's. Like their closest relatives, koalas, they can get almost all the water they need from vegetation.

Their dozy reputation hides another surprising wombat characteristic — wombats can turn on the power if they need to. The average wombat could win a gold medal in a 100 metre race with a human, as they can maintain 40 kilometres an hour for 150 metres. They've also been seen to leap over metre-high fences and squeeze through gaps only 10 centimetres high.

There are three species of wombats, all found exclusively in Australia. The common wombat (Vombatus ursinus) lives in the coastal and highland areas of south-east Australia. The southern hairy-nosed wombat (Lasiorhinus latrifrons) can be found in the arid areas of southern Australia, and the endangered northern hairy-nosed wombat (Lasiorhinus krefftii) is found in central Queensland, although you'll be very lucky to see it, at this or any other time of year.

Fact file: Other info: Wombats are nocturnal animals who spend a lot of time in burrows. But it's not all hiding and snoozing underground! The work in digging a 10 m burrow is equivalent to walking 120 km, and they can maintain a speed of 40 km/hr for 150m. There are three wombat species in Australia - the common wombat, the southern hairy-nosed wombat and the northern hairy-nosed wombat (which is very rare). The common wombat is solitary and sometimes aggressive, with coarse, dense bristle-like hair. The northern and southern hairy-nosed wombats are more social and more docile. They have angular, blocky heads with softer, silky fur.

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The uncommon wombat

The northern hairy-nosed wombat is only found within three square kilometres of Epping Forest National Park in central Queensland. Dr Alan Horsup, Senior Conservation Officer in the park, calls them the 'uncommon wombat'.

"Northern hairy-noses are amongst the top ten most endangered mammals in the world," he says. "To put it into perspective, take the giant panda, the most famous endangered animal in the world. There are 1800 giant pandas left. There are only about 100 of these creatures."

"It's the only tropical wombat. We nearly lost it. They were down to perhaps thirty individuals in the 1980's. If they become extinct, it will be the first large animal extinction since the thylacine. We don't want that to happen."

Weighing in at up to 40 kg and 1.3 m long, the 'northerns' are the largest species of wombat. Their fine, silky fur, squared-off heads, pig-like noses and large ears are just part of what differentiates them from common wombats. Geneticists calculate the commons and the hairy-nosed wombats are less closely related to each other than chimps and humans.

Dr Horsup is developing techniques to establish new populations within the park, and is looking for suitable land to establish a colony outside Epping Forest National Park.

"It's really risky having all the animals in just one spot," he says, "A disease outbreak or a bushfire could be a disaster."

The Northern Hairy-nosed Wombat Recovery Program is using innovative techniques such as DNA hair analysis and remote 'burrow-cams' to monitor these shy, scarce creatures with minimal disturbance. Limited funding means that the remote park is staffed by volunteers, but the list of those wanting the chance to see one of these exceptional beasts is long.

"We've started to see lots of young wombats' signs around tracks and diggings and in videos now," he says. "There's quite few new burrows. It's pretty encouraging."

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Joey spotting

Over the next few months, if you're in South Australia, you might see a joey (a baby wombat) poke its head out of a burrow, or a pouch, for the first time.

Unlike the common wombat and the northern hairy-nosed wombat, the southern hairy-nosed wombat has a seasonal, and therefore predictable, breeding cycle. Most southern hairy-noses are born from late August to October.

In a never-witnessed journey, the one gram neonate makes its way to the pouch and attaches to a teat. There may still be an elongated teat in the pouch which is accessed by the previous year's joey, now living outside the pouch.

"Like some other marsupials they can produce the appropriate milk for each offspring from different teats, " says Peter Temple-Smith, from Monash University. "Often they'll wean the older one off pretty quickly."

The maternal bond remains however, and the older juvenile wombat will stay around for many months to come.

"Sometimes, if they're still in the pouch, you might even catch sight of a two-headed wombat," says Temple-Smith. "While mum's grazing, there'll be a head poking out the other end chewing on a bit of grass as well. They learn from the pouch what's food and what's not."

With time, the females leave the joey in the burrow while they go out foraging. And after a while they just come out with her.

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Wombats don't make good pets!

Many people might remember the lovable Fatso, who lived with the local policeman in the old TV series A Country Practice. However, anyone thinking about 'adopting' one needs to think twice. First of all, it's against the law to keep them without a licence.

"They're a protected animal," says Gaylene Parker, an animal carer. "They have to be released and it has to be done the right way."

Parker has looked after over 500 orphaned wombats and now trains carers.

"We've had older confiscated wombats brought to us and 95 per cent of them die because they've been kept with a person, and they've run around the house with them during the day. When it comes to the age where it feels that it should be doing certain things, it doesn't have the confidence and skills to go out into the wild and fend for itself."

If someone finds a baby with a mother killed by the side of the road, they should contact WIRES, the RSPCA, National Parks or a vet, she says.

In any case, wombats are not the most domestic of animals.

"We once had a wombat come through a sliding door at full pace, just leaving a wombat-sized hole in it," says Triggs. "They're not destructive really. It's just that to get somewhere, it doesn't matter what's in the way, they'll just push it aside rather than go around."

And if you're still having second thoughts about having a lovable wombat for a pet, try tapping your knuckles on a common wombat's rump. The shiny patch over their rump marks an area of tank-like toughness formed by matted hair, centimetre-thick skin, cartilage and bone. It's used as a shield to block a tunnel against predators or even to crush the skull of an attacking dingo or fox against the burrow roof. It's like knocking on a door-mat!

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Links

Wombats — NSW National Parks and Wildlife Factsheet

Northern Hairy-nosed Wombat — Queensland Conservation Council fact sheet

Common and Southern Hairy-nosed Wombat — Queensland Conservation Council fact sheet

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Credits

With thanks to all the people mentioned above, and especially James Woodford, Patsy Davies and Nick Mooney.

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