Koalas are one of the species most at threat from man-made climate change (1). Why? Many reasons – I’ll outline some here.
1. Climate Change will increase the frequency and intensity of bushfires.
Bushfires kill koalas (2). They always have. In one example we have personally witnessed 90% of the koala population killed by a bushfire. Under natural conditions the koala population would slowly recover or recolonise from nearby unburnt habitat. But that takes time, and plenty of suitable adjoining habitat. Increasingly, koalas have neither. Due to climate change, bushfires are happening more often, to more forest, are hotter and more deadly.
So what’s the answer? We must fight climate change. But we won’t stop the bushfires immediately. However, we can give koalas more habitat to retreat to, and recolonise from.
2. Climate Change will increase the frequency of heat waves.
Koalas have limited options when the day is too hot. They are not able to quickly vacate an area affected by a heatwave. They often have no access to water. So when the temperature exceeds 37 degrees Celsius day after day, they simply overheat and die.
Due to climate change, heatwaves are occurring more regularly throughout the koala’s range. Two heatwaves in the summer of 2009 in Gunnedah killed 25% of the region’s koalas (3).
So what’s the answer? We must fight climate change. But again, we won’t stop the heatwaves soon enough to save koalas. What we can do is save/plant trees near water. Rivers, dams and lakes cool the air and koalas are attracted to these water bodies in heatwaves. They will also drink and sit in water if they need to. So by planting trees near water, we can make it easier for koalas to survive heatwaves.
3. Climate Change will make trees less edible to koalas.
Koalas need eucalyptus trees, they basically eat nothing else. Eucalyptus is poor-quality fodder, already rich in toxic chemicals, tannins and poisons, and low in water, protein and carbohydrate. Increasing temperature and carbon dioxide levels in the air are expected to increase the toxins/tannins in eucalyptus leaves and decrease the protein (4). So a tree a koala can eat today – a ‘good tree’ – will become a ‘bad tree’ – a tree they can’t eat, or can only eat in small doses – in a couple of years from now.
So what’s the answer? More habitat. Each koala will need more trees to live off in future so that they can choose the ‘good trees’ over the ‘bad trees’. The areas of koala forest we currently have we must keep, and new ones need to be planted.
There are many other ways that climate change will affect koalas, but these are the ‘big guns’.
Decisive action needs to be taken to save koalas, and quickly. You can help:
- Lobby your government hard to take decisive action on climate change. Attend climate protests, write letters, sign petitions, and vote for representatives that promise to take action to limit fossil fuel use quickly.
- If you are buying a house, make sure the developer did not clear forest to make that land available.
- Think twice about buying agricultural products from Queensland and native timber products from NSW or Victoria. These states are clearing forest at an alarming rate, largely for increased agriculture and timber/wood chips. Queensland & NSW are also the states that have seen the largest drop in koala numbers.
- Buy and use recycled paper. Try not to use disposable paper products.
- Support our Make a Home for Clancy Project – you can donate here, or come on one of our Koalas & Kangaroos IN THE WILD tours, or, if you’re local, plant trees with us on a Koala Conservation Day for Locals.
LINKS & REFERENCES:
(1) IUCN (2009) 10 species most vulnerable to climate change: https://www.iucn.org/content/species-climate-change-hit-list-named
(2) National Koala Management Strategy: http://www.environment.gov.au/system/files/resources/165139fc-3ab5-4c96-8b15-d11a1ad882ab/files/koala-strategy.pdf
(3) Wildlife and Climate Change: http://books.google.com.au/books?hl=en&lr=&id=bG8bAgAAQBAJ&oi=fnd&pg=PA150&dq=koalas+gunnedah&ots=d5XrBjIHkx&sig=zko7ty772sdIw0xjww9Z5lIPQFo#v=onepage&q=koalas%20gunnedah&f=false
(4) IUCN koala fact sheet: http://cmsdata.iucn.org/downloads/fact_sheet_red_list_koala.pdf
5) IUCN (2017) Climate Change Hitting Species Hard: https://www.iucn.org/news/climate-change/201703/climate-change-hitting-species-hard-%E2%80%93-we-should-keep-eye-most-vulnerable