WA's prescribed burning regime is becoming increasingly problematic amid a drying climate, failing to adapt to protect rare and endemic biodiversity, a parliamentary committee has heard.
The public hearing was scheduled by the Environment and Public Affairs Committee, following a petition calling for an independent review of the long-held approach.
Prescribed burning is a method of applying fire to a predetermined area to reduce the severity of bushfires and to help protect lives and property, as well as biodiversity.
Among the thousands of signatories to the petition was a group of scientists, known as the Leeuwin Group.
Biologist Stephen Hopper, formerly the director of Perth's Kings Park and the Kew Gardens in London, is a part of that group and said the way prescribed burns were carried out was putting rare plants and animal species at risk.
Drought threatens biodiversity
He pointed to a now-barren and charred peat swamp in the Walpole wilderness as one example of what he calls a "systematic" issue in the way burns are carried out.
The area was set alight by a prescribed burn in 2019.
"This is like an island within a forest, and because it's island-like it has a range of animals and plants that are found nowhere else on the planet," he said.
"So if one of these swamps go up, it's of far greater concern from a conservation point of view than the adjacent forest."
Dr Hopper said climate change was making it easier for those areas to catch alight during a burn.
"Where once the fire would have stopped at the edge, now they come into the heart of them," he said.
"I am not about stopping prescribed burning, not in the least because life and protection is fundamental.
"But we need to be very strategic about how we go about that."
Numbat habitat decimated
Peatlands are recognised by the Department of Biodiversity, Conservation and Attractions (DBCA) as fire sensitive ecosystems, and the Walpole peat swamps are known habitats of the endangered sunset frog.
During the hearing other examples were raised, including a burn in the Fitzgerald River Park in October 2019 that was meant to burn 2,000 hectares of land, and instead took out 10,000 hectares.
A prescribed burn in the South West which decimated one of only two numbat habitats left in Western Australia was also raised.
An analysis of the area by DBCA found there was no evidence numbats had been killed.
Climate change increases risk
Bushfire is a familiar and increasing threat to Australia, with research showing the number of extreme fire weather days increasing with climate change.
West Australian authorities have used prescribed burning to mitigate the severity of bushfires for more than half a century.
In order to reduce the build-up of flammable fuels, they have a target to burn 200,000 hectares of forest a year in the south-west.
This aims to keep 45 per cent of the forest younger than six years old.
In a response to the petition, DBCA, which manages the prescribed burn program, said the target was supported by evidence and “decades of operational evidence”.
A paper by Dr Matthias Boer in 2009 examined the historical occurrence of bushfire with prescribed burns in the Warren region over a 50-year period.
The findings found prescribed fire treatments had a significant effect on bushfire up to six years after treatment.
The study did not make any recommendations about fire management policies or targets for the Warren Region or other forest regions of South West WA.
Aerial ignition concern
During the hearing, the 200,000-hectare target was pinpointed as one of the key concerns with the prescribed burn program, as was the method of burning with aerial ignition.
Botanist Joanna Young from the environmental group Fire and Biodiversity WA said she believed this was leading to a “burn above all else” mentality.
“There has been systematic failure over a lot of burns, where they haven’t met objectives,” she said.
Smaller, cool burns were suggested as a better option, including the option for more Noongar cultural burns.
Dr Young told the hearing there needed to be an independent review, frustrated by what she called a “tin ear” to their concerns.
“We have had no studying, no monitoring,” she said.
“I’m hoping if there is an independent review that we could find common ground in the community for better protecting (communities), agreeing where there has to be compromise to perhaps biodiversity sacrifice to some degree.
“But at least an acknowledgement of what frequent hotter burns will do.”
Protecting peat swamps
DBCA executive director of regional and fire management services Jason Foster told the hearing its program was not target-driven, but risk-driven.
He told the committee prescribed burning was also important to protect biological assets, like peat swamps.
"We know during large scale summer intense bushfire that the whole landscape gets consumed, including those peat swamps," he said.
"So we are looking at opportunities with the burn program to undertake [prescribed burning] to give an added level of protection to those peat swamps."
Mr Foster said the department considered all evidence and was constantly adapting.
"We are really fortunate as a department to have over 60 years of both operational and science to support our prescribed burn program," he said.
"And certainly there has been an evolution of the way we undertake prescribed burning and the way we implement those burns."
Burns extensively planned
Fire management services manager Stefan de Haan told the committee the department conducted monitoring before and after each burn to consider biodiversity impacts, which informed their future burns approach.
"Because that's obviously integral information to what we do, and the reality is potentially changing some of the elements that we undertake," he said.
But he said the information was generally not made public.
He said they were also looking at updating their mapping of areas.
The committee will decide whether to inquire further into the matter or to finalise the petition.
