Koalas ‘Functionally Extinct’ After Australia Bushfires Destroy 80% Of Their Habitat
By Trevor Nace (*) - 23. November 2019 - see update below
As Australia experiences record-breaking drought and bushfires, koala populations have dwindled along with their habitat, leaving them “functionally extinct.”
The chairman of the Australian Koala Foundation, Deborah Tabart, estimates that over 1,000 koalas have been killed from the fires and that 80 percent of their habitat has been destroyed.
Recent bushfires, along with prolonged drought and deforestation has led to koalas becoming “functionally extinct” according to experts.
Functional extinction is when a population becomes so limited that they no longer play a significant role in their ecosystem and the population becomes no longer viable.
While some individuals could produce, the limited number of koalas makes the long-term viability of the species unlikely and highly susceptible to disease.
Deforestation and bushfires destroy the main nutrient source of koalas, the eucalyptus tree. An adult koala will eat up to 2 pounds of eucalyptus leaves per day as it’s main staple of nutrients. While eucalyptus plants will grow back after a fire, it will take months, leaving no suitable food source for koalas and starvation a likely scenario for many.
Many are urging the Australian government to enact the Koala Protection Act, written in 2016 but never passed into law and molded after the Bald Eagle Protection Act in the U.S. The Koala Protection Act would work to protect habitats and trees vital to koalas as well as protect koalas from hunting.
Recent viral videos of Australians rescuing koalas has led to increased donation to support hospitalization and help for burned koalas.
The Port Macquarie Koala Hospital setup a Go Fund Me page seeking donations to help the hospital treat injured koalas. To date, they have raised $1.33 million, well over their $25,000 goal. This comes from over 30,000 donors.
Part of their effort is to install drinking stations for koalas in areas devastated by the fires. The funds will also be used for a “Koala Ark” as a refuge for burned koalas to live in a healthy habitat during rehabilitation.
Trevor Nace - Senior Scence Contributor. I am a geologist passionate about sharing Earth's intricacies with you. I received my PhD from Duke University where I studied the geology and climate of the Amazon. - Follow me on Twitter or LinkedIn.
By Michael Le Page - NewScientist - 17 May 2019 , updated 25 November 2019
These iconic animals aren’t dying out
This story was written in May 2019. The claim that koalas are functionally extinct was repeated after forest fires in November 2019. This time it has also been claimed that 80 per cent of their habitat has been destroyed. But ecologist Diana Fisher says the fires damaged only 1 million hectares of the 100 million hectares of forest in eastern Australia, and that koalas are still nowhere near functionally extinct.
Who has said koalas are “functionally extinct”?
The Australian Koala Foundation, which lobbies for the animals’ protection, has put out a press release stating that it “believes koalas may be functionally extinct in the entire landscape of Australia”. The release triggered a flurry of worried headlines.
So are they?
No, although many populations of koalas are falling sharply due to habitat loss and global warming.
Could they go extinct?
There is no danger of koalas going extinct in Australia overall, says biologist Christine Adams-Hosking of the University of Queensland, who has studied the marsupials’ plight. “But at the rate of habitat clearing that is going on, we are going to see increased local population extinctions,” she says.
Why has the AKF made this claim now?
The claim was made on the eve of elections in Australia in which environmental issues such as climate change have become a big issue. The AFK has called on politicians to act. “There’s a lot of politics going on, and somehow the koala gets involved,” says Adams-Hosking.
What does functionally extinct even mean?
The term is used in several different senses. It can mean that a species has declined to a point where it can no longer plays the role it once did in a ecosystem, with significant effects on that ecosystem. Some define it even more narrowly, saying a species is functionally extinct when its decline leads to the extinction of other species. That’s not what we’re talking about here.
There are more meanings?
Yes. Others use it – arguably incorrectly – to describe a species that is probably extinct but we can’t be sure. For instance, when researchers failed to find any river dolphins in China in 2006, they declared the baiji “functionally extinct”.
Surely this isn’t what the AKF meant?
No. The term is also used to describe a species where there are still many surviving individuals but the species is thought to be doomed in the long-term because, say, of the loss of genetic diversity. This is the sense of functionally extinct meant by the AKF. “This is a scientific term to describe ‘beyond the point of recovery’,” wrote the head of the AKF, Deborah Tabart, in a blog post.
But koalas haven’t passed this point?
Some local populations of koalas are indeed heading towards functional extinction, says Adams-Hosking. “But Australia is a big country, there are koalas all over the place and some of them are doing fine,” she says. “You can’t just make that statement broad-brush.” Adams-Hoskins also questions the AKF’s claim that just 80,000 koalas remain. In 2016, she and colleagues estimated that there are around 300,000.
That sounds better…
No one knows for sure how many are left. What we do know is that koala numbers are falling as the eucalyptus forests they live in and feed on are cut down to make way for cities and farms. Habitat loss is the biggest threat, as it is to most wildlife.
What about climate change?
It is already having a big impact, says Adams-Hosking, causing some populations to decline 80 per cent. Koalas can’t cope with day after day of temperatures above 36°C, as has been happening in the west of the country during the many recent heatwaves. Extreme droughts are also harming the eucalyptus trees they feed on.