Extinction is forever

| May 22, 2023

In the lead-up to World Biodiversity Day on 22 May, the Invasive Species Council has reviewed recent research showing Australia has been averaging at least 4.5 probable extinctions every decade since the 1960s, which is more than previously thought.An average of almost 3 extinctions per decade have been caused mainly by invasive species. A new report by the Invasive Species Council – GONE: Australian animals extinct since the 1960s – profiles the losses of 23 animal species, including species recently assessed by the Threatened Species Recovery Hub as probably extinct (with a >70% likelihood). ‘Telling the stories of these modern extinctions is a way of honouring those lost species, all unique to Australia, but also to learn from the past so as to better avoid future extinctions,’ said lead author and biologist Tim Low. ‘The report reveals that extinctions remain shockingly common and that both the extinction drivers and the animals being lost are becoming more diverse. ‘When you look at animal extinctions since European colonisation, one major threat stands out as an exterminating force – invasive species,’ said Mr Low.Up to 1960, the main causes were cats and foxes preying on mammals, and rats (as well as human hunters) preying on island birds. But since 1960, the exterminators have included several other invasive species – chytrid fungus, wolf snakes and trout – as well as other threats such as land clearing and hydrological changes. Frogs and reptiles have joined the lists of those gone forever. ‘As new invasive species arrive and spread, as climate change and fire regimes intensify and as more habitat is lost, the causes of extinction will continue to multiply,’ said Mr Low. ‘If the Australian government is genuinely committed to zero extinctions they need to start dealing effectively with the multitude of threats and prevent new threats arising.‘Australia has long had one of the highest rates of animal extinctions in the world (the highest for mammals). ‘The stories of modern extinctions show we have not yet learned from past mistakes. It is not enough to try to save species on the verge of extinction. Unless we focus on abating the major threats, more species will disappear before they are recognised as doomed. ‘The average Australian has not heard or known about most of these native animals that are gone forever. Telling their stories is a way to honour them and raise awareness of the problem’, said Mr Low.