posted July 22, 2015 04:24 PM            

Feral cats have been identified as the main culprit behind Australia's high rate of mammal extinction, with more than 10 percent of species wiped out since Europeans settled here two centuries ago.

Environment Minister Greg Hunt has said the advice he has received is that the cats number 20 million across the country and devour countless native animals every night.

"They are tsunamis of violence and death for Australia's native species," he told the Australian Broadcasting Corporation last week.

Hunt said a target of eradicating two million feral cats had been set for 2020, in addition to creating feral-free enclosures to aid the recovery of birds and mammals among other measures.

The government has stressed the eradication of cats will be carried out humanely, but Bardot urged the government to reconsider the plan which she said was "appalling" to the international community.

"This animal genocide is inhumane and ridiculous. In addition to being cruel, killing these cats is absolutely useless since the rest of them will keep breeding," she said in the English translation of the open letter to Hunt.

Bardot, who said the money set aside to destroy the animals would be better spent on setting up a large-scale sterilisation campaign, said Australia's public image was being hurt by its culling of animals.

Earlier this year officials said that close to 700 koalas had been killed off in southeastern Australia because overpopulation led to the animals starving, while feral camels and wild horses have been culled in the Outback to stop them destroying land.

"Your country is sullied by the blood of millions of innocent animals so please, don't add cats to this morbid record," Bardot wrote.

People for the Ethical Treatment of Animals (PETA) said Wednesday that the culling of animals had been proven in the past to be ineffective and called on the government to look for long-term, non-lethal solutions including suppressing the cats' fertility.

"Not only is shooting and poisoning cats cruel, culls have been shown to be unsuccessful in the long term," a spokeswoman for PETA Australia told AFP.

"The use of poison in suburban areas also puts domestic cats, dogs, and carnivorous wildlife at risk."

Animals Australia said it was sceptical that the government's proposed measures would make a significant difference to the wild cat population.

"It's worth noting that the primary and most significant threat to the continued existence of Australia's native species is the destruction of their habitat and food sources," said the organisation's Lisa Chalk.

The Australian Wildlife Conservancy, which works to protect endangered animals, said there was no doubt that feral cats, along with foxes and rabbits, were having a damaging impact and it was important that the government was attempting to tackle the issue.

"It's hard to be critical of the plan because it's the first time someone has focused so much on cats. Someone needs to act," chief executive Atticus Fleming told AFP.

"We want to do it in a manner that's as humane as possible but, yes, culling two million cats is necessary," said Fleming.

While the government felt that killing the animals with poisoned bait was an option they could not avoid now, other biological and genetic solutions would be needed in the future, he added.

"If you decide you want feral cats in our landscape then you are effectively saying you do not want native mammals such as our bilby."

The bilby is a small marsupial unique to Australia.