Invaders taking toll on threatened species Tracey Ferrier, Australian Associated Press February 19, 2019 3:56am

Species introduced into Australia are having a devastating effect on native plants and animals that are at risk of disappearing, new research shows.

A study published this week found 82 per cent of Australia's 1533 threatened species are under pressure from foreign invaders and the rabbit is the worst of them all.

The European rabbit is a problem for 321 threatened species, taking pole position in a toxic top 10 ahead of a fungus-like microorganism that causes plant disease, as well as feral pigs, cats, goats and foxes.

Lead researcher Stephen Kearney from the University of Queensland says his findings demonstrate the urgent need for national plans to take down the invaders and protect Australia's biodiversity.

He looked at 160 invasive species and looked at how they were affecting the prospects of threatened species across the nation and the results were sobering.

Thanks to their voracious appetites, the European rabbit was found to be a disaster for struggling plants but also for smaller animals.

"They eat threatened plants. And if there's enough rabbits, and enough pressure, they can stop the seedlings of that plant from growing," he told AAP.

"That stops recruitment so you get a lot of older plants but no new ones coming through."

Rabbits are also affecting the prospects of small mammals that need good ground cover to survive and avoid being eaten by predators, including feral cats which finished fourth on Mr Kearney's list.

"They really do pose quite a big, indirect threat to a lot of animals as you lose that habitat complexity."

He said the same was true for another invader, phytophthora, a soil fungus that can wipe out root systems and decimate the habitats of threatened animals.

Mr Kearney said his study showed the need for much greater investment in the management of at-risk plants and animals.

But he said there must also be better coordination in managing the threats posed by invaders.

"We really do need these nationally coordinated plans," he said.

The study, by the Threatened Species Network, has been published in the scientific journal Pacific Conservation Biology.

FACTBOX:

Australia's 10 worst invaders and the species they are threatening

European rabbit: 321