Photo: Kristian Bell

Birds shrinking, plants dying, some insects thriving due to climate change

Researchers have observed numerous examples of climate change already affecting Australian plants and animals, including plant extinctions, dieback in forests, changes to vegetation, changes in the size of birds, and shifts in reproduction behaviour.

‘There’s lots of awareness of the impacts on marine systems, such as failing coral reefs and mangrove forests, but less on land-based systems being affected by climate change,’ said Professor Ary Hoffmann, from the University of Melbourne’s School of BioSciences and Bio21 Institute.

Professor Hoffmann and colleagues have just published results from a study identifying eight examples of effects being observed around Australia.

Heat stress is causing canopy dieback across forests and woodlands in south-western Western Australia, a region rich in biodiversity.

‘Rainfall in the region has declined by 15 to 20 per cent in the last 30 years and temperatures have risen by one degree. There has been acute drought and a series of heatwaves. Canopy declines have occurred elsewhere too, as well as substantially increased fuel loads, leading to likely increases in fire spread rates,’ said Professor Hoffmann.

‘Smaller animals find it easier to cope with hotter conditions. Of the 24 Australian bird species that have been studied to date, many of them are becoming smaller.’

Widespread species do better than those with a narrow range. Alpine ecosystems globally are at acute risk from climate change, with some flora and fauna in Australia considered endangered.

‘The Bogong High Plains have experienced shifts in vegetation, with grasses decreasing and shrubs becoming more common. Climate change poses a substantial ongoing threat to the endangered Mountain Pygmy-possum.’

Climate change affects insect populations and is predicted to increase frequency and severity of insect pest outbreaks.

‘There are repeated outbreaks of what appears to be a new psyllid species across thousands of hectares of the critically endangered Cumberland Plain Woodlands of Western Sydney.’

‘As to the future, I do have some optimism. Part of the reason for this study was to encourage thinking about management. We can strengthen ecosystems to help some species adapt, particularly if we can predict what will happen beforehand.’

The research findings were published in the journal Austral

(Image credit: Steve Shattuck)