Wombat burrows help other critters survive after fires

Tracey Ferrier |

Cameras have revealed the popularity of wombat burrows with a wide range of other native species.
Cameras have revealed the popularity of wombat burrows with a wide range of other native species.

Wombat burrows act as survival boltholes for a surprising array of creatures after bushfires hit, a study suggests.

Researchers have analysed camera trap images from NSW’s Woomargama National Park and Woomargama State Forest, where more than 18,000 hectares burnt during the Black Summer fires.

Sensor cameras were installed in front of 28 wombat burrows in areas with varying degrees of fire damage.

Cameras were also positioned at 28 control locations, which had been impacted by fire but did not have burrows.

Native species such as bush rats, agile antechinus, lace monitors and painted button-quails were more prevalent around burrows compared to similar sites without them.

The cameras caught 30 species inspecting a burrow, 11 foraging at them, 10 entering or leaving a wombat hidey-hole, four drinking from a flooded burrow and one taking a bath.

Ecologist Grant Linley was the lead author on the study and is a PhD candidate with Charles Sturt University’s Gulbali Institute.

Researcher Grant Linley
Researcher Grant Linley says wombat burrows play an important role in forests prone to bushfires. (HANDOUT/WORLD WILDLIFE FUND (WWF))

He says the burrows of common wombats play a valuable role in Australia’s fire-prone forests and that makes the decline of the species more concerning.

“They’re the only surviving native species capable of digging deep, wide burrows. Their value as providers of shelter and a refuge for numerous species is only going to increase as fires become more intense in the future,” he says.

“Wombats alter the soil, topography and vegetation around their burrows. They turn over tonnes of soil constructing a burrow and their scats increase nitrogen levels which boosts herb cover.

“We think these changes increase the foraging opportunities for small insectivores and omnivores … and more small vertebrates hanging around could then be drawing in larger native predators so the impact of burrows may be cascading through the system.”

A red-necked wallaby looks into a wombat burrow
Animals such as a red-necked wallaby were filmed inspecting wombat burrows. (HANDOUT/WORLD WILDLIFE FUND (WWF))

The university’s Professor Dale Nimmo co-authored the paper and says shelter can be a rare commodity after bushfires and wombat burrows are potentially aiding in the survival, persistence and recovery of other animals.

WWF Australia scientist and study co-author Kita Ashman says wombat burrows could help some species deal with climate change.

“Wombats’ extensive burrow systems can create microhabitats that enhance water retention, assist in nutrient cycling and contribute to overall ecosystem resilience,” Dr Ashamn says.

“In an increasingly unstable climate, wombats can be valuable agents in adapting to and mitigating some of the impacts of climate change.”

The research has been published in the peer-reviewed Journal of Mammalogy.