Tales of wombat ‘heroes’ have gone viral. Unfortunately, they’re not true

Wombats may not usher other animals into their burrows, but their warrens still protect other species in bushfires.
Liv Falvey/Shutterstock

Dale Nimmo, Charles Sturt University

If you’ve been following the bushfire crisis on social media and elsewhere, you may have seen reports of benevolent wombats herding other animals to shelter into their fire-proof burrows.

These stories went quickly viral – probably reflecting the appetite for good news after the horrors of the bushfire crisis. However the accounts are not entirely accurate.

Wombats do not heroically round up helpless animals during a bushfire and lead them to safety. But wombats do help other animals in a different way – even if it’s not their intention.

Accidental heroes

Wombats can emerge as accidental heroes during a bushfire, by providing a safe refuge underground for other wildlife.

Wombat warrens – networks of interconnecting burrows – are large and complex, and considerably shielded from the above-ground environment. Small mammals are known to use wombat burrows to survive an inferno.

One study of the southern hairy-nosed wombat, for instance, found warrens with 28 entrances and nearly 90 metres of tunnels.

Wombats aren’t benevolent. They’re accidental heroes.

What’s more, temperatures deep within burrows are very stable compared to surface temperatures, with daily temperature fluctuations of less than 1℃, compared to 24℃ on the surface.

This thermal buffering would help a great deal during intense fires, and you can understand why other species would want access to these safe havens.

The wombat sharehouse

By placing camera traps outside 34 wombat burrows, a 2015 study showed a surprising variety of animals using southern hairy-nosed wombat burrows. Researchers observed ten other species, six of which used them on multiple occasions.

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The intruders ranged from rock wallabies and bettongs to skinks and birds. Little penguins were recorded using burrows 27 times, while the black-footed rock wallaby was observed using wombat burrows more often than wombats – nearly 2,000 visits in eight weeks! They were even observed using the burrows to specifically avoid birds of prey.

But wombats aren’t alone in providing real estate for other species. Hopping mice, echidnas, sand swimming skinks, barking geckoes and numerous invertebrates were found using the warrens of bettongs and bilbies in arid Australia.

Anybody home?

It’s also important to recognise wombats don’t have “a burrow”.
Rather, they have multiple burrows within their home range. In fact, a 2012 study tracked one wombat to 14 different burrows.

While wombats are often regarded as quite sedentary, another study found the average home range size of common wombats is 172 hectares.

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They spend a few nights sleeping in one burrow, before moving onto another.

Since each wombat has multiple burrows, many can be vacant within a home range, and abandoned burrows are common in some areas. A 2007 study showed that even among “active” burrows (those with signs of recent use), only one in three are actually occupied by a wombat at any given time.

Australian black-footed rock wallabies often use wombat burrows as makeshift lodges.
Ken Griffiths/Shutterstock

This means, at times, other species may not need to share burrows with wombats at all. It’s vacant real estate.

So how might a wombat react to an uninvited guest? This is difficult to know, and likely depends on who’s visiting. Wombats prefer not to share burrows with other wombats, although burrow sharing can be common when wombat populations are very high in one place.

In her book Wombats, Barbara Triggs recalls a fox being chased from a burrow by an angry wombat. Meanwhile, the crushed skulls of foxes and dogs in wombat burrows suggest not all intruders are welcome.

That a suite of species use wombat burrows suggests wombats may not notice or care about squatters – so long as they don’t pose a threat. But more research is needed on the fascinating interactions that take place in wombat burrows, particularly during fire.

The battle is not over

While empirical studies are needed, the available evidence suggests wombats may well provide an important refuge for other wildlife during fire.

In any case, it’s important to recognise that surviving fire is only half the battle.

Wombats and their house guests face a medley of challenges post-fire – not least avoiding predators in a barren landscape and eking out a living in a landscape with scarce food.

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Dale Nimmo, Associate professor/ARC DECRA fellow, Charles Sturt University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Mangy marsupials: wombats are catching a deadly disease, and we urgently need a plan to help them

Julie Old, Western Sydney University and Janine Deakin, University of Canberra

You may have seen recent media reports that wombats are under threat from a mysterious killer disease. That disease is sarcoptic mange, and while it affects the two wombat species that are not in immediate danger of extinction, it threatens to wipe out local populations.

Of the three wombat species, the northern hairy-nosed wombat is in the most precarious position overall – it is officially listed as critically endangered, with only about 200 individuals left. The other two, the southern hairy-nosed wombat and bare-nosed wombat, are both listed as of “least concern”, although all wombats have been affected by threats associated with the advent of European settlement.

Although the southern hairy-nosed and bare-nosed wombats are not in danger of extinction, both are under threat from sarcoptic mange, and some local populations are at risk of dying out.

Mange is a severely debilitating disease that affects a range of different mammals. It is caused by an infestation of mites, which burrow into the skin, causing severe itching, abnormal thickening of the skin, and loss of fur.

Usually the first sign of wombat mange is hair loss and thickened skin on the head, then progression to thickened crusty skin on the shoulders, flanks and limbs. Often the wombat will become deaf and blind due to thickening of the skin in and around its ears and eyes. Over the following months, the disease progresses to the point where all of the wombat’s skin is severely thickened, and eventually death occurs.

Tackling mange

Some wildlife groups have begun treating wombats with anti-parasitic treatments, with varying success. This typically involves invasive techniques (physically capturing the wombats and administering an injection), or administering “pour-on” products using treatment flaps. Both these techniques are very labour-intensive, as wombats require several treatments over a period of weeks or even months.

In addition, wombats can use several different burrows in a night, and some burrows are used by different wombats at different times, which makes it difficult to ensure that only the affected wombat is treated. And of course, these treatments are only possible in areas where wombats can be accessed by humans – treatment in remote areas is virtually impossible.

In the longer term, some of these treatments are likely to lead to resistance in the mites, further endangering the wombat populations. Both techniques may also raise the wombats’ stress levels over time, which can hamper their ability to maintain immunity against other parasites and diseases.

Healthy wombats are the aim.
JJ Harrison/Wikimedia Commons, CC BY-SA

A national wombat strategy

We therefore need to develop a nationwide management strategy to ensure the long-term survival of wombats, an iconic Australian marsupial that through its burrowing activities also helps to create valuable habitat for a host of other animals.

To develop this strategy, we first need to understand how big the sarcoptic mange problem really is. Field research to assess the levels of mange in the populations is limited by the large distribution area of wombats throughout parts of southern and eastern Australia. However, in combination with data currently being collected from citizen-scientists using an online system called WomSAT, much more information can be gained.

WomSAT allows anyone to log sightings of wombats (dead or alive, and if alive their level of mange) and wombat burrows. Together, field research and citizen-science information can be used to determine the distribution and severity of mange, and to identify other threats to wombats throughout Australia.

Second, we need to learn more about why wombats are so badly affected by mange, and why their immune system fails to fight the parasites. Unbelievably, little is currently known about the wombat immune system, most probably because of a lack of funding and research on wombats in general – especially when compared with other quintessentially Australian animals such as koalas and kangaroos.

It is clear that more is needed to ensure the survival of a truly unique Australian animal, as part of the wider effort to preserve Australia’s biodiversity. There has never been a better time to work towards a nationwide strategy to save the wombat, with recent genome technology coming to the forefront of marsupial immunology research and our ever-increasing need to preserve our unique wildlife. We need to act now.

Julie Old is Associate Professor, Animal Science and Zoology at Western Sydney University and Janine Deakin is Associate Professor in Genetics, Institute for Applied Ecology at University of Canberra

This article was originally published on The Conversation. Read the original article.

Australia: Re-wilding & the Northern Hairy-Nosed Wombat

The link below is to an article reporting on the practice of re-wilding and how it is assisting in the conservation of the Northern Hairy-Nosed Wombat.

For more visit:
http://www.guardian.co.uk/environment/2013/jul/05/wombats-endangered-species-hope

Australia: Queensland – Hairy-Nosed Wombats

The link below is to an article reporting on how man-made burrows are helping Hairy-Nosed Wombats survive and breed.

For more visit:
http://www.australiangeographic.com.au/journal/designer-burrows-man-made-for-rare-wombat.htm

Article: Australia – Hairy-Nosed Wombat

Numbers Are Slowly Rising

The following link is to an article reporting on slowly growing population of the extremely rare Hairy-Nosed Wombat. They have now risen from about 30 in the early 1980s to about 140 now.

For more visit:
http://www.news.com.au/breaking-news/endangered-wombats-a-nose-in-front/story-e6frfku0-1226367687864