Nature at risk
Australia is one of 17 recognised megadiverse countries, which together hold the majority of earth’s biodiversity. Our Southwest Ecoregion is one of only 34 recognised global biodiversity hotspots, with nearly 3000 species of native plants found nowhere else. Yet 7% of our unique native mammals are already extinct and 20% threatened with extinction. Unmitigated climate change is predicted to result in the extinction of over 40% of all native mammal, bird, reptile and amphibian species in Queensland alone.
Scientists predict that a global temperature rise of 2–3°C will result in about 20–30% of the Earth’s species being at risk of extinction 1.
In Australia, at least 90 species are already considered at risk.
Some Australian species under threat are:
- Nest temperatures of 25–32°C are necessary for the successful incubation of green turtle eggs. If the sand gets too warm, only females are born and at higher temperatures the embryos will die before hatching
- Snow cover in the mountain pygmy possum’s alpine habitat acts as a winter blanket. Projected warming could leave it more exposed to cold weather and predators
- Many Australian Frogs from cooler regions are threatened by a fungal disease that seems to thrive in warmer climates
- During hot weather, flying fox colonies move deeper into the forest for protection. Rising temperatures could see them stranded by the heat and habitat loss
- Within 20 years, many eucalypt species on which koalas depend could be threatened by extreme temperatures and changing rainfall. More frequent and intense bushfires could also be disastrous
- A report recently released by WWF showed that birds are already changing their behaviour in response to climate change. Up to three-quarters of bird species in the Wet Tropics could become extinct.
Global warming stresses ecosystems through temperature rises, water shortages, increased fire threats, weed and pest invasions, intense storm damage and salt invasion, just to name a few. Some of Australia’s great natural icons, such as the Great Barrier Reef, are already threatened.
Scientists predict that a 1.5°C temperature rise will result in 97% of the Great Barrier Reef being bleached.
Higher summer water temperatures are the main cause of bleaching.
The Australian Alps are considered one of our three most vulnerable ecosystems under potential climate change.
Snow depth in the Australian Alps has reduced by 30–40% since the 1950s and the resulting feral mammal intrusions have been detrimental to native species.
Kakadu and the Northern Territory
By 2030, the average warming over the Northern Territory will be about 0.2–2.2°C relative to 1990, causing most of the NT to become drier.
This warming will result in a greater number of more intense cyclones and rising sea levels are likely to devastate Kakadu’s low-lying freshwater ecosystems.
Scientists predict that a global temperature rise of 2–3°C will result in about 20–30% of the Earth’s species being at risk of extinction2.