WA Premier Mark McGowan says there is no evidence numbats were killed or affected by a prescribed burn in a forest known to contain one of the state's only wild numbat populations.
The burn, which scorched nearly 1,900 hectares of forest, was lit by the Department of Biodiversity, Conservation and Attractions (DBCA) in Perup, east of Manjimup, on March 25.
Conservationists who inspected the Perup bush before and after the burn believe most of the numbat population was wiped out in the fire.
However, Mr McGowan said the DBCA had advised him there was no evidence numbats had been killed.
"The advice I have is there is no evidence that any numbats were killed or affected and that measures were put in place to protect them," Mr McGowan said.
Numbats were once widespread across the western half of Australia but Perup and Dryandra, near Narrogin, remain the only two major populations.
Farmer Bill Smart, whose property backs onto the Perup reserve, and who has photographed numbats in the area for years, said he could not imagine how the marsupials would have survived the burn.
In 2014, the numbats' conservation status was elevated to "endangered".
It's estimated that fewer than 2,000 numbats are left in the wild.
Mr McGowan said he was concerned about protecting the marsupial but drew short of backing a plan, proposed by the Opposition, for an auditor general investigation into prescribed burning in WA..
Fire intensity higher than planned: Minister
In a statement, WA Environment Minister Amber-Jade Sanderson said DBCA had advised "there were areas where the intensity of the fire was higher than planned".
"The impact on the local numbat population is still being determined," she said.
"However, special attention was paid to protecting the numbats prior to this prescribed burn."
An internal review of the fire will be completed this month.
