500 land-based vertebrates face extinction threat

Human activity and climate change are driving more than 500 land-based vertebrates-amphibians, birds, mammals and reptiles-to the brink of extinction, according to researchers.

Professor Paul Ehrlich from the department of biology at Stanford University in California, said: "When humanity exterminates populations and species of other creatures, it is sawing off the limb on which it is sitting, destroying working parts of our own life-support system."

He added: "The conservation of endangered species should be elevated to a national and global emergency for governments and institutions, equal to climate disruption to which it is linked."

Ehrlich is one of the authors of a study published in the scientific journal, Proceedings of the National Academy of Sciences of the United States of America.

The study says the extinction is accelerating and calls for immediate global conservation actions to prevent a "catastrophic ecosystem collapse".

Researchers looked at 29,400 species-on the International Union for the Conservation of Nature's Red List of Threatened Species and from Birdlife International, a worldwide alliance of nongovernmental organizations that promotes the conservation of birds and their habitat-and found that 1.7 percent, or 515 of these species, are on the brink of extinction.

They also say 84 percent of the 388 terrestrial vertebrate species that have fewer than 5,000 remaining individuals are located in the same geographical regions as species on the brink and may therefore soon face a similar risk due to the human-driven collapse of regional biodiversity.

Additional analyses suggest that terrestrial vertebrate species on the brink have collectively lost approximately 237,000 populations since 1900.

Call for global action

According to the authors, the findings underscore the need for global action to prevent further loss of terrestrial vertebrate species.

The study says, "There will be more pandemics if we continue destroying habitats and trading wildlife for human consumption as food and traditional medicines.

"It is something that humanity cannot permit, as it may be a tipping point for the collapse of civilization. What is at stake is the fate of humanity and most living species."

"We are facing our final opportunity to ensure that the many services nature provides us do not get irretrievably sabotaged," said Professor Gerardo Ceballos of the National Autonomous University of Mexico, who led the research.

Commenting on the study, Diana Fisher, associate professor, School of Biological Sciences at the University of Queensland, and vice president of the Australian Mammal Society, said species on every continent except for Antarctica are under threat.

"This is an important study that deserves attention," Fisher said. Why? "Because so many people do not realize how much of the world's wildlife faces impending extinction."

Australia has the second highest number of land vertebrates on the brink of extinction, despite being the smallest continent. Only South America has more species on the brink, because of the many critically endangered frogs there.

The study highlights the wildlife trade, but, in Australia, habitat loss and invasive predators and diseases are particularly serious threats.

Amy Coetsee, a threatened species biologist at Zoos Victoria, said: "Globally, humans are driving many species towards extinction at an accelerated rate."

She said the latest study is a "wake-up call" to take urgent action on a global scale, to reverse the extinction crisis.

"If we don't, civilization is at risk. Australia has the worst mammal extinction record in the world. Many of our unique species are on the brink of extinction due to habitat destruction, introduced species, such as cats, foxes, cane toads, and climate change," Coetsee said.

Fertile soils degraded

"We can already see the evidence of what happens when we lose species. Since European settlement, our once fertile soils have become degraded as our digging mammals, such as bandicoots, potoroos and bettongs, have disappeared across most of their range. These diggers perform an important role when they turn over the soil every night looking for food."

She added: "Whilst we are currently on a devastating trajectory, there is hope we can reverse the extinction crisis. With strong environmental laws that protect native wildlife, long-term investment into threatened species recovery and a renewable energy future, we will save species from extinction."

Chris Johnson, professor of wildlife conservation at the University of Tasmania, said the current rate of extinction of species is higher than at any time since 65 million years ago, when the collision of a space rock with the Earth killed off dinosaurs and many other species.

"Threats to species in today's world-things like habitat destruction and climate change-are growing rapidly," Johnson said.

"This suggests the rate of extinction may be about to increase further. The significance of this study is that it provides evidence for that impending rise in extinctions," he said.

"The tragedy of all of this is that we have the knowledge to save species from extinction, and doing that is cheap in a global context. But this task is just not given enough priority by society and governments."