November 10, 2024
Ground-penetrating radar used to map critically endangered northern hairy-nosed wombat burrows

In the middle of the southern Queensland bush, a man in a high-vis orange shirt looks starkly out of place as he slowly pushes a strange four-wheeled machine across the uneven, scrubby landscape. 

To the untrained eye, it looks like Max Thomas is searching for gold or mowing the grass as the sun shines down on him on this 30-degree winter’s day near St George.

But in the red dirt, stubby little footprints — almost like toddlers’ feet — give away what he’s really looking for.

A man pushes a lawnmower like device across rough ground with others watching on

Geospatial technician Max Thomas operates a device that sends radio waves underground to map wombat burrows.(ABC Southern Qld: Tobi Loftus)

The geospatial technician and a team of conservationists are mapping the burrows of one of the world’s most critically endangered animals — the northern hairy-nosed wombat.

“It’s the largest burrowing herbivore in the world,” explains Australian Wildlife Conservancy (AWC) field ecologist Andy Howe.

“It’s larger than the other two species of wombat that we have in Australia.

A wombat walks out of a burrow

The northern hairy-nosed wombat is one of the world’s most endangered animals.(Supplied: Australian Wildlife Conservancy)

“They max out at about 35 kilos, and they’re over a metre long. So, they’re an enormous burrowing animal.”

The lawnmower-looking device is covered in screens and sensors, and each push over the grassy scrub sends pulsating radio waves underground.

The conservation team is acutely aware that the mapping work being done here is imperative to the marsupial’s survival.

a man stands in the bush smiing

Andy Howe from the Australian Wildlife Conservancy.(ABC Southern Qld: Tobi Loftus)

From 30 to 300 wombats

There are only an estimated 315 northern hairy-nosed wombats left, and they are spread out across two protected reserves in rural Queensland.

The wombat species once lived in areas stretching from central Victoria to central Queensland, but by the 1980s, land clearing and pests had reduced their numbers to just 35.

The remaining wombats were isolated to one small pocket of central Queensland: Epping Forrest National Park, near Clermont.

Conservation work began at that park, and by the mid-2000s, the species was translocated to the Richard Underwood Nature Refuge, near St George.

Today, their population has grown to more than 300.

“They’re survivors,” says Leanne Brosnan from the Wombat Foundation.

“I’m amazed at their ability to survive, to come back from the brink the way they have.”

A woman smiles while standing in bushland in southern Queensland.

Leanne Brosnan from the Wombat Foundation.(ABC Southern Qld: Tobi Loftus)

But as Mr Howe points out, having “all your eggs in one basket” is a risk they cannot afford.

“If there’s a drought or a catastrophic fire at Epping, that’s where the majority of the animals are,” he says.

“There’s no space for error in terms of we’re only talking about 300-plus individuals.

“So having our population spread out over their historic range will allow us to manage this population better and safeguard it into the future.”

Charting the wombat burrows

A new study — a collaboration between AWC, the Wombat Foundation, and Subsurface Mapping Solutions — is now underway at the St George site to map the wombats’ burrows.

two men wearing high-vis orange shirts stand outside a van filled with technology.

Geospatial technician Max Thomas and Subsurface Mapping Solutions managing director Andrew Watson prepare to scan wombat burrows.(ABC Southern Qld: Tobi Loftus)

Subsurface Mapping Solutions managing director Andrew Watson says this is a first for his company, which generally maps underground services like phone, power, and water systems for design feasibility and survey works.

“We’re using a multi-array, ground-penetrating radar system that shoots radio waves into the ground, and it records a signal coming back up,” Mr Watson says.

“And that’s how we see our targets.”

small footprints on sand caused by a northern hairy-nosed wombat.

The northern hairy-nosed wombat generally comes out of its burrow at night.(ABC Southern Qld: Tobi Loftus)

Ms Brosnan says the results will provide a clear understanding of the structure of the wombats’ burrows.

“It’s critical in identifying potential new habitat for the northern hairy-nosed wombats so that we know more about their burrowing needs,” she says.

What has struck them most is how the wombats use the different soil structures at St George and at Epping.

“So here [at St George], we’re assuming that the burrows have a different structure and depth,” Mr Howe says.

“Understanding how deep the burrows go allows us to dictate where we can look for potential future habitat.”

Scrubby landscape near St George in southern Queensland.

The Richard Underwood Nature Refuge is located about an hour’s drive north of St George.(ABC Southern Qld: Tobi Loftus)

More sites planned

Queensland’s Department of Environment and Science (DES) has secured a third site at Powrunna State Forest, also near St George, with plans to transfer a wombat population within the next couple of years.

The DES’s species recovery plan also highlights the need for a fourth site by 2041.

Ms Brosnan says she hopes the work will eventually lead to seeing the species of wombat once again thriving in the wild.

“That’s the very long-term plan,” she says.

Get our local newsletter, delivered free each Wednesday

link

Leave a Reply

Your email address will not be published. Required fields are marked *