Updated

Up to 45 rare species of wallaby, bandicoot and other Australian animals could become extinct within 20 years unless urgent action is taken to control introduced predators and other threats, scientists warned Wednesday.

Dozens of mammals, birds, lizards and other vertebrates in the remote northwestern Kimberley region are at risk from hunting by feral cats and from destruction of their native habitat by wild donkeys, goats and fires, a study of the conservation needs of the area shows.

"We're in the midst of a massive extinction event in Australia and the north has really been the last stronghold for many species of birds and mammals and reptiles," said Tara Martin, a co-author of the report by the government-funded Commonwealth Scientific and Industrial Research Organization.

Nearly 30 percent of the endangered species identified in the study are unique to the Kimberley region, while others, like the golden bandicoot and golden-backed tree rat, have already disappeared elsewhere in the country.

"The Kimberley is really their last chance on Earth," Martin told The Associated Press.

The report says immediate funding of $96 million is needed to start a range of conservation programs, and that annual funding to protect the region's native animals should be doubled to $40 million.

The study, based on scientific data and information from about 30 experts with experience in the region, was commissioned by the Wilderness Society conservation group and released Wednesday.

It says the most effective ways of combating the threat of extinction are to reduce the number of wild donkeys and goats that compete with native species for scarce food and water, and to do more to fight wildfires that scorch the landscape.

It says attacks by feral cats should also be reduced by educating the community about the threat pets pose to small native animals and by building fences.

Donkeys, goats and cats are among dozens of species introduced by humans to Australia as stock animals or pets, but are now considered invasive species in many areas where wild populations swell because they have few natural predators. Martin said feral cats alone kill some 500,000 native animals in the region every day.

Martin said some benefits from the proposed conservation efforts would be seen relatively quickly, while others would take several generations.

Richard Hobbs, an ecologist at the University of Western Australia who did not participate in the study, said it was the first time a wide range of reliable information about the problem in the Kimberley has been compiled, and that the findings back smaller studies of individual species.

"The position for the Kimberley is that, at the moment, we are ahead of the extinction curve," he said. "However, if we let things continue unabated, there is little doubt that the same wave of loss of species will occur in the Kimberley as has occurred elsewhere, particularly in southern parts of Australia."

Hobbs said one encouraging sign from the report is that the measures proposed, while costly, are not too difficult to contemplate.

"The price tag sounds expensive, but relatively speaking it's a huge conservation bargain," he said.

(This version CORRECTS name of university in paragraph 12 to University of Western Australia)