Hundreds of extinct species rediscovered

Javan Elephant once thought extinct was rediscovered in 2008 (credit: Jan Vertefeuille)

An amazing piece of research has just been published by the University of Singapore. Together with their colleagues at the University of Adelaide and Princeton University they discovered that over the last 122 years at least 351 species which had been declared extinct have reappeared.

Average extinction was 61 years before rediscovery.

The study was the first ever research to look at mammal, amphibian and bird species that had been declared extinct but later found again. The average length of time that the animal was ‘extinct’ was 61 years. The actual lengths of years that the species was considered extinct ranged from as little as 3 years all the way to the re-appearance of a species after 331 years.

Rediscoveries, without aggressive conservation, likely represent the delayed extinction of doomed species and not the return of viable populations.

One of the big question first asked in the paper was whether these new discoveries were viable or just a slow continuation on the path to extinction.

Not all good news as many species remain threatened.

It was not all good news for these species. Most of them are still threatened and mainly because of habitat loss. The majority of the species studied appeared to be confined to very small ranges and this makes them particularly at risk from habitat loss.

The lead researcher, Brett R. Scheffers, who is from the Department of Biological Sciences at National University of Singapore said, ”We still have much to discover and these results indicate that it may not be too late for many species that have gone unseen for many years.“

The study also highlighted the dangers of there being such a long gap between sightings. With an average of 61 years of ‘extinction’ it makes planning for the conservation of the species very difficult because monitoring can be over such a long time.

False extinction claims could threaten habitats.

One of the dangers is that because a species have not been seen for many years it may be considered no longer alive and it’s habitat turned over to alternative use such as agriculture.

Scheffers said, “Rediscoveries, without aggressive conservation, likely represent the delayed extinction of doomed species and not the return of viable populations. In short, there is hope but we must step up rapid conservation efforts.”

Many extinct species now actively being looked for.

Many of the big conservation groups are now actively looking for extinct species to find out if they can be rediscovered. For example in 2009 BirdLife undertook active surveys for 47 species of birds that have been considered extinct for up to 187 years. Conservation International have also released details of plans to go looking for 100 ‘extinct’ species of amphibians.

One of the trends that the research discovered was that the rate at which extinct species have been rediscovered have increased in recent times. Whether this is because of better and more surveying techniques or because of less habitat to search through the researchers did not say.

The rediscovered species was fairly equally split over different types of animals with 104 amphibians, 144 birds, and 103 mammals rediscovered.