New index shows endangered species

Scientists have developed a new measure that shows just how close critically endangered species such as the tiger are to becoming extinct.

The index shows it may be better in conservation terms to give the highest priority to species that have a better chance of recovery, such as the Sumatran rhinoceros rather than its Javan cousin.

Called SAFE (Species Ability to Forestall Extinction), its developers at the University of Adelaide and James Cook University say it is a big leap forward in the way threats to species are measured.

Professor Corey Bradshaw of the University of Adelaide says it assesses just how close species are to their minimum viable population.

"While we provide a formula for working this out, it's more than just a formula; we've shown that SAFE is the best predictor yet of the vulnerability of mammal species to extinction," he said in a statement on Thursday.

"For example, our studies show that practitioners of conservation triage may want to prioritise resources on the

Sumatran rhinoceros instead of the Javan rhinoceros.

"Both species are critically endangered but the Sumatran rhino is more likely to be brought back from the brink of extinction based on its SAFE index.

"Alternatively, conservationists with limited resources may want to channel their efforts on saving the tiger, a species that is at the 'tipping point' and could have a reasonable chance of survival."

SAFE is designed to be an adjunct to the International Union for Conservation of Nature Red List of Threatened Species, not a replacement.

Professor Bradshaw said a combined approach is a good method to gauge the relative safety of a species from extinction.

Of the 95 mammal species considered in the team's analysis, more than one in five are close to extinction, and more than half are at 'tipping points' that could take their populations to the point of no return.