Between 1-3 Australian insects and other native invertebrate species are becoming extinct every week, according to a peer-reviewed study published this week, revealing the country’s biodiversity crisis is far greater than previously recognised.
The research was published this week by in Cambridge University Press, estimating that about 9,000 invertebrates have become extinct since European arrival to the continent in 1788.
“These estimates dwarf the number of formally recognised extinctions of Australian invertebrates (10 species) and of the single invertebrate species listed as extinct under Australian legislation,” the study’s abstract said.
The authors predict 39-148 species will become extinct in 2024, flying in the face of the Australian government’s pledge to prevent all new extinctions.
The lead author and professor, John Woinarski, emphasised the importance of invertebrates, saying they are “the foundation of all healthy environments and a liveable planet”.
“Invertebrates provide myriad essential functions that people depend on like pollinating crops and breaking down organic matter,” he said in a media statement.
“As we lose invertebrates the health of our crops, waterways, forests, and even local parks and backyards will decline.”
While the government has formally recognised the extinction of the Lake Peddler earthworm in legislation, Woinarski said most species become extinct before they were described and named by scientists, referring to this event as “ghost extinctions”.
“Despite their incredible importance, there has been a long-running bias against invertebrates, with little funding available for their research and conservation,” he said.
The study highlighted that conservation efforts more broadly have been biased towards iconic and well-known groups of animals.
CLUTCHING AT AIR
Researchers came up with their deductions via two approaches, the first was to calculate the average extinction rate as a percentage across Australian endemic species in well-known taxonomic groups, and apply this proportion to the estimated number of endemic Australian non-marine invertebrate species.
The second method was to use the conservation status assigned by the International Union for Conservation of Nature and Natural Resources to invertebrate species and applied the global percentage of extinct invertebrate species to estimate number of Australian invertebrate species – assuming Australian invertebrates have become extinct at the same rates as invertebrates globally.
For each of these approaches, the authors used a mathematical technique known as the Monte Carlo simulation to come up with its conclusions on both the number of extinctions that have occurred since European settlement, and the number that will occur in 2024.
While the authors “explicitly recognise” many assumptions and caveats in their estimations, they said most of these figures were likely conservative.
“To some extent, our assessment if clutching at air: although we can estimate the likely number of extinctions, we cannot put names to (most of) them. This invites scepticism and the anonymity of the extinct species may simply reinforce public and political disinterest and incredulity,” the study stated.
It said more investment was needed to increase the knowledge about invertebrates, as well as inventory and monitoring and identifying the key threatening processes that affect them.
The research also called for more use of the precautionary principle to allow for the listing of poorly-known species at high risk of extinction, and the inclusion of co-dependent species when listing better-known threatened species, among other recommendations.
Additionally, co-author Jessica Marsh, from the University of Adelaide and member of the Biodiversity Council, said it was great to see a growing recognition of the impact of pesticides on invertebrates, and moves towards reducing their usage.
“Using pesticides in your garden often kills the beneficial invertebrates your garden needs like bees and flies that pollinate, lady beetles that help control aphids, and worms that improve your soil,” she said.
“Many invertebrate species have already lost a huge amount of habitat, and ongoing habitat loss remains a major threat.”
CATS OUT OF THE BAG
Separately, Australian environment ministers signed off on the national threat abatement plan for feral cats – a key driver of animal extinctions in Australia.
A communique released by the ministers said it was the first threat abatement plan to be made jointly by state, territory, and Commonwealth ministers under national environmental law.
“[It] is an important first step on coordinated action to reduce the devastating impact of feral cats on millions of birds and other wildlife,” the communique said.
Ministers agreed to work together to implement the plan consistent with state and territory legislative and policy frameworks and priorities, and to “consider” making further national threat abatement plans for priority invasive species.
Experts recently told Carbon Pulse that the abatement plan was a positive first step, but committing sufficient funding to ensure its execution would be key.
The adoption of the plan by ministers was welcomed by the Australian Land Conservation Alliance.
A Linkedin post by the alliance said however they were concerned that since the launch of the government’s National Roadmap for protecting and conserving 30% of Australia’s land by 2030, no tangible next steps have been collectively agreed to by Australia’s environment ministers.
By Mark Tilly – mark@carbon-pulse.com
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