What should have been a damp swamp beside Victoria’s Bemm River in East Gippsland was a blackened crunchy mess when Nick Clemann arrived in early March.
“These are habitats not known for burning. To have them converted to just smouldering charcoal was pretty confronting,” says Clemann, a senior scientist for the Victorian state government’s Arthur Rylah Institute for Environmental Research.
Clemann was in Croajingolong national park to search for the threatened swamp skink.
Lifting up logs and rocks, Clemann would usually expect to find dozens of skinks, but he found only a handful of survivors among the charcoal. At other sites nearby, he found none.
The swamp skinks are among the astonishing 2.46bn lizards and snakes estimated to have been in the path of Australia’s fires last summer.
Clemann is a reptile specialist and has been out across Victoria assessing the impacts of the fires. He’s worried about the alpine she-oak skink, which doesn’t burrow but hangs around on vegetation that would have been incinerated. Some patches of its favourite habitat were spared, but others around Mount Kosciuszko were not.
He says until last summer’s fires, the places around East Gippsland had always been considered a refuge for threatened lizards. A place for them to hang on. Now he’s not so sure.
Land of the lizards
As the Guardian revealed last month, an interim report from 10 scientists estimated that almost 3bn animals were in the path of Australia’s bushfires. More than 2bn of those were squamates – also known as lizards and snakes.
Separately, conservation experts advising the department of environment have identified 23 reptile species that need urgent action.
But what does it mean to lose millions – perhaps billions – of reptiles from Australia’s landscape?
Reptiles make up such a large number of animals hit by the fires because of their ubiquity across Australia. They are literally everywhere.
“They’re the most diverse group of terrestrial vertebrates that we have,” says David Chapple, an associate professor at Monash University.
“They occur across every single different type of environment and habitat. They’re a part of every food web of every ecosystem.”
Prof Rick Shine, a biologist and reptile expert at Macquarie University in Sydney, says Australia is known as the “land of the lizards”.
“Australia is a tough place to make a living and you have droughts and floods and bushfires with long periods of little food available.
“Reptiles can survive long periods without access to food and water and so they tend to dominate a lot of Australian ecosystems in a way they don’t in other parts of the world.
“These reptiles are incredibly important in a wide range of Australian ecosystems. Taking them out through threats like bushfires will have a strong impact on our ecosystem function and a huge impact on biodiversity.”
Compared with other species, comparatively little is known about Australia’s lizards.
As Australia’s east coast was ablaze late last year, scientists published a comprehensive assessment of the health of the nation’s snakes and lizards. The last major assessment was in 1993.
The research found Australia had 1,020 species of lizard and snake, of which 96% exist nowhere else in the world.
For comparison, says Dr Hal Cogger, an expert on reptiles at the Australian Museum who co-wrote Australia’s previous reptile action plan, North America has 390 species and the UK just six.
About 7% of Australia’s species are considered threatened and among those the research found one in five existed entirely outside protected areas such as national parks.
Since 1993, three reptile species – all on Christmas Island – have been declared extinct in the wild and 36 have been added to the national threatened species list.
Chapple, who wrote an action plan for the country’s snakes and lizards on the back of that work, says the conclusions of the 1993 action plan were eerily similar to the latest efforts.
“After more than 20 years our message was exactly the same – we are still getting a grasp on species. It’s hard to get long-term population trends and you don’t know enough to implement effective recovery strategies.”
Cold and scaly
Now retired, Cogger spent 40 years at the Australian Museum – mostly around the herpetology department. The reason reptiles are an understudied group is simple, he says.
“This goes back to support for conservation of all species,” he says. “The reality is that the publicity is concerned with the warm and cuddly rather than the cold and scaly.
“We tend to overlook that the lizard population can be in the tens of thousands and will have a big impact on other animals like the insects they eat but also the birds and warm cuddly mammals that eat them.”
During workshops to develop the most recent action plan, Chapple says, no one had entertained the idea that the impact of fires could be so widespread.
“With these fires we’ve seen entire regions being burned and that was a scale of threat that we did not believe was possible.
“It’s made us reassess the way we try to estimate the likelihood of an entire species being lost.”
Even if reptiles can survive fires, they already have pressure from other human-caused problems, such as habitat destruction, increasing frequency of fires and predation by feral animals, in particular cats.
“These creatures are pretty resilient, but the difficulty comes when we add multiple threatening processes,” Shine says. “It reaches a point where the sum total of challenges becomes too much.”
Across Victoria’s reptile populations, Clemann is worried that species already under pressure are becoming isolated in pockets, increasing their vulnerability from fires.
“Even in the worst cases you’ll get survivors, but the problem comes when there are so few individuals that you lose genetic diversity – you get a genetic bottleneck with high levels of in-breeding.
“When we think about climate change and increasing fire frequency, a concern is that a single bottleneck event is undesirable, but several of them can be absolutely catastrophic.”
Another largely unseen problem in burnt areas, says Clemann, is that when vegetation grows back over years and decades, it tends to be dense.
“The reptiles were there because an area provided the right thermal environment, but the forest becomes incredibly dense after fires.
“That brings new challenges to reptiles because their ability to lie out in the sun has been taken from them.”
Strategies for survival
Clemann is busy planning projects to save the state’s reptiles – even those that almost no one has heard of.
One lizard – the hand-sized mountain skink – lives in small family groups in hilly regions that were badly burned. Recent monitoring trips have recorded fewer and fewer of them, and Clemann fears that “by the time we get to taking it seriously” the species could be too far gone.
He also wants to take samples from some lizard’s tails to assess their genetic health.
An emerging conservation strategy – called genetic rescue – could be one solution, where specimens from different isolated groups are mixed together to make them healthier.
But he says aside from tackling climate change, the solutions to helping reptiles are local – stopping further habitat loss through developments and transport infrastructure.
“If we are genuine about wanting to stop the obvious decline and extinction trajectory of some of these species, then we first need to stop doing harm,” he says.
“If we want them to have the resilience to cope with climate change and disease and fires, then we need to ease all the other pressures that are within our power.”