Endangered dunnarts take shelter under tin roof refuges in simple but game-changing conservation method

News article | 28 July 2023

A cryptic and endangered Kangaroo Island mammal on the brink of extinction following the Black Summer bushfires has found new hope for its survival under the most Australian of outback shelters.

The humble corrugated iron sheet has attracted dozens of the cute but feisty Kangaroo Island dunnarts in a development that has shocked researchers and rewritten future conservation strategies.

In late 2021 Zoos SA and the Kangaroo Island Landscape Board trialled different trapping techniques to capture this extremely elusive species. Unexpectedly, corrugated iron sheeting proved to be more effective than any of the methods trialled.

So in March, the Kangaroo Island Landscape Board’s Dunnart Recovery team, with support from WWF-Australia, placed a series of corrugated iron sheets and terracotta tiles across 14 sites in the Flinders Chase National Park and Ravine des Casoars Wilderness Protection Area.

What happened next blew the lid off all expectations.

Using motion activated cameras, dunnarts were observed visiting 100% of refuges at burnt sites, with a staggering 75% of these entered. Visitation was lower at unburnt sites, suggesting that the artificial refuges provide critical habitat for the Kangaroo Island dunnart following a catastrophic fire event.

Endangered dunnarts take shelter under tin roof refuges in simple but game-changing conservation method — Checking a corrugated iron refuge (Image Martin Stokes).

“In the space of three months we captured 31 dunnarts under these refuges, 20 of which were previously unknown to us,” Project Manager Paul Jennings said. “These sorts of numbers are completely unheard of for the species.

“We’re detecting KI dunnarts at more sites than ever before, and we’re detecting them more frequently. The results have exceeded our expectations. The future is looking much more positive for the species than we ever anticipated.”

Mr Jennings said that KI dunnarts were previously thought to be primarily solitary animals.

“But for us to be able to come out to these sites and lift a sheet of iron and find two, three, four dunnarts denning together communally under these artificial refuges has really rewritten our understanding of what we know about this species.”

The catastrophic Black Summer bushfires of 2019/20 burnt more than 96% of the KI dunnart’s habitat and it was feared that a lack of suitable refuges would leave them vulnerable to extinction.

“As part of the study we wanted to look at the fire resistance and suitability of these refuges, so we teamed up with the National Parks and Wildlife Fire Management Program and installed the refuges immediately prior to a prescribed burn,” Mr Jennings said.

“What we found was that in open habitats where the refuges were installed, the temperature beneath only reached 40 degrees for a matter of minutes as the fire passed over them. This has provided us with the first insight into how they would perform during a wildfire and also how we might further insulate these refuges in the future.

“With future climate change predictions including more frequent and intense bushfires, threats around land modification and predation from feral cats, we’re focused on features or refuges that can be put in place to not only provide protection during a bushfire, but post-fire when these species are most vulnerable.

“In burnt habitat, the natural den sites used by dunnarts are often shared with other species. So providing additional resources in terms of places where they can den under the corrugated iron, along with the nests that we’ve constructed underneath, has proven to be perfect habitat for dunnarts.”