As tinderbox conditions continue to hamper wildlife assessment and rescue efforts, bushfires in Victoria have burned habitat crucial to bird and animal species, including eastern bristlebirds and dingoes.
Some plant species are feared extinct.
Prof Don Driscoll, a terrestrial ecologist at Deakin University, said he was particularly concerned for the state’s population of endangered eastern bristlebirds – shy songbirds with cinnamon-brown feathers – after fires near Mallacoota burned about 60% of their habitat at Howe Flat.
The state’s population numbered fewer than 200 birds, and any that survived the flames would now be exposed, Driscoll said. “That’s a particular concern because these ground-inhabiting birds are hanging around in dense vegetation, and they rely on that for protection from predators.”
Six years ago, authorities mounted a rescue mission to capture 14 birds, fearing the species was at risk of extinction from the black summer fires. There was no emergency mission this time around, Driscoll said.
There are fewer than 200 eastern bristlebirds left in Victoria. Photograph: Darryl Whitaker/Zoos Victoria
The state’s environment department said active fires had prevented it from sending in specialist staff to assess the situation. Once the area was declared safe, the department would establish accurate figures of affected birds and work to reduce threats, such as controlling foxes and cats.
“While this is a concerning situation for the eastern bristlebird population, we’ve had promising recovery results in the recent past, including establishment of a recently translocated population at Wilsons Promontory to help manage extinction risks from these types of bushfire events,” said James Todd, the department’s chief biodiversity officer.
Bushfires that ignited across Victoria in January have since torn through more than 435,000 hectares of land, as back-to-back heatwaves pushed fire danger to extremes, and caused thousands of flying foxes to perish in the worst mass mortality event since black summer.
Wildlife Victoria said there was likely to have been a substantive loss of animals given the ferocity and scale of the fires.
“The impact of bushfires on wildlife can be catastrophic. Native animals are often unable to escape fires and are highly vulnerable to death, dehydration, disorientation, burns, injury, and the loss of food and habitat,” chief executive Lisa Palma said.
The charity continued to receive reports of animals affected, mainly kangaroos, koalas and wallabies, after a record number of calls at the peak – more than 1,100 in a single day. Assistance was provided where possible, but many firegrounds remained unsafe for rescuers and volunteers to enter.
Researchers don’t yet know the full extent of the damage caused by the fires, and are waiting until firegrounds are declared safe to collect monitoring equipment. Photograph: Wildlife Victoria
Victoria’s environment department has deployed wildlife teams across multiple firegrounds to search for and assess affected animals, but a full picture of the devastation has yet to emerge.
All animals were impacted by the fires, with mammals particularly vulnerable, said Driscoll, the lead author of a Nature paper detailing the biodiversity impacts of the 2019-20 fires.
“They can’t fly away like many birds can. They’re too big to hide in small crevices like some of the frogs, reptiles and insects could,” he said. Animals that sheltered in tree hollows, including greater gliders and yellow-bellied gliders, were especially at risk, he said.
Prof Euan Ritchie, an ecologist at Deakin University, said animals that survived the heat and flames could still suffer or perish in the aftermath through greater exposure to foxes and cats, reduced food and the loss of hollow-bearing trees.
Victoria was the most-cleared state in the country, he said, which compounded the effects of other threats.
Fires in the north-west of the state had burned through 60,000 hectares of Wyperfeld national park, an important habitat for wilkerr (dingo), as well as critical nesting trees for endangered flame-crested cockatoos.
Researchers don’t yet know the full extent of the damage, Ritchie said – they are waiting until firegrounds are declared safe to collect monitoring equipment – but at least one animal was thought to have died, from an adult population smaller than 80 dingoes.
“As part of recovery efforts, Parks Victoria has worked with the Barengi Gadjin Land Council to install temporary water points in areas of Wyperfeld national park,” Todd said. “The water points will help wildlife in areas where water is scarce to discourage animals from moving on to private property to seek out water.”
Some threatened plants may have been lost for good.
Prof David Cantrill, chief botanist at Royal Botanic Gardens Victoria, held grave concerns for the endangered southern shepherd’s purse, a small native herb with spoon-shaped leaves and “pretty white flowers”, after fires near Harcourt burned Mount Alexander, home to the last remaining wild plants.
There are fears the southern shepherd’s purse may be extinct after fires near Harcourt. Photograph: Andre Messina/Royal Botanic Gardens Victoria
Another major fire near Mount Lawson encompassed a fenced flora reserve containing the only known population of critically endangered summer leek orchids, along with several state-listed species, including the endangered dusky bush-pea and grey rice-flower.
Botanists were holding out hope that some orchid tubers may have survived in the ground, “providing it’s not too hot and hasn’t burnt too deeply into the soil”, Cantrill said.
“We will be able to make assessments towards autumn when anticipated rainfall and improved conditions may lead to germination and re-sprouting,” Cantrill said. “Then our botanists will move in to assess damage to populations and secure seeds and plant cuttings, to propagate as backup populations.”
Driscoll said fires were becoming more severe, extensive, and frequent due to human-caused climate change. As well as acting faster on climate change, he said states such as Victoria needed the capability for “rapid attack” – quickly identifying when fires started and investing in enough equipment and people to control and extinguish them before they escalated.
Some areas, such as rainforests and wetter zones, should be flagged for special protection, he said, similar to how Wollemi pines were saved in New South Wales during black summer.
Dr Tom Fairman, research fellow at the University of Melbourne’s FLARE Wildlife Research, said the state needed an overarching strategy for protecting priority ecosystems as bushfires became more frequent and severe. Elements of the natural landscape were already being lost as fires burned, and then burned again, he said.
“We shouldn’t be surprised when a fire happens and some of these ecosystems start collapsing.”