Australia is losing up to three native insects and other invertebrates to extinction every week, according to research.
More than 9,000 invertebrate species have disappeared since European colonisation, with another 39 to 148 species predicted to become extinct in 2024 despite the Australian government’s pledge to prevent all extinctions.
According to the paper, published in Cambridge Prisms: Extinction, many of the losses were “ghost extinctions” where critters were gone before they could be named.
Lead author Prof John Woinarski, from Charles Darwin University and the Biodiversity Council, said Australians were blind to the loss of invertebrate species.
“We’ve caused far more harm, loss of species, loss of nature, than what we’ve recognised and acknowledged to date,” he said.
Only one invertebrate extinction – the Lake Pedder earthworm – was officially recognised under the federal Environment Protection and Biodiversity Conservation Act, he said.
The Tasmanian worm became extinct after its only habitat – the lake’s original beach – was flooded in the early 1970s.
Woinarski said threats facing invertebrates were similar to those facing other species, including climate change, habitat loss, land clearing, waterway pollution, misuse of insecticides and introduced species.
“Climate change is a major factor for invertebrate conservation,” he said. Warming temperatures and worsening bushfires put many at risk, especially ancient creatures such as velvet worms, which he described as “relics of an age of millions and millions of years ago, when Australia used to be cooler and wetter”.
Dr Jessica Marsh, a conservation biologist affiliated with the University of Adelaide and co-author of the paper, specialises in spiders – especially those living in extremely restricted zones considered at high risk of extinction.
Cave invertebrates were particularly vulnerable because often a single species is confined to a single cave. A single threat or event – such as a large fire or habitat clearance – could wipe them out.
Dr Kate Umbers, a conservation scientist based at Western Sydney University and managing director of non-profit Invertebrates Australia, said the estimated number of extinctions probably sounded shocking to many but it wasn’t a surprise for people working in the field.
“Species are going extinct before we can name them,” she said.
Umbers, who was not an author of the paper, said invertebrates – animals without a backbone – made up 95% of animal species on Earth. Their “enormous, mind-boggling diversity” included butterflies, bees, cicadas, worms, moths and spiders.
Her own research focused on critters adapted to alpine areas, including bogong moths, mountain katydids and skyhoppers that change colour from black to turquoise when their body temperature exceeds 25C.
Umbers said many of the “cutie crawlies” found in Australia were unique and played a critical role maintaining healthy ecosystems and agriculture.
“We’re custodians of an incredibly large and incredibly important proportion of global biodiversity,” she said. “We should care about that.”
