September 29, 2010

Missing Or Extinct Species Being Rediscovered

A recently publsihed study reports that over a third of mammal species considered extinct or missing have been rediscovered, and a lot of effort is wasted in trying to find species that have no chance of being found again.

According to the United Nations, species face an accelerated rate of extinction because of pollution, climate change, habitat loss and hunting, and that this rate of loss is putting ecosystems and economies at even greater risk.

Researchers at the University of Queensland in Australia said that having a better understanding of patterns of extinction could channel more resources to find and protect species listed as missing before it is too late.

"In the past people have been very happy to see individual species found again but they haven't looked at the bigger picture and realized that it's not random," university research fellow Diana Fisher, lead author of the study, told Reuters.

Fisher and her colleague Simon Blomberg studied data on rediscovery rates of missing mammals to determine whether or not extinction from different causes is equally detectable.  They also wanted to find out which factors affect the probability of rediscovery.

The team found that species affected by habitat loss were more likely to be misclassified as extinct or to remain missing than those affected by introduced predators and diseases.

"It is most likely that the highest rates of rediscovery will come from searching for species that have gone missing during the twentieth century and have relatively large ranges threatened by habitat loss," they say in the report in the Proceedings of the Royal Society B journal.

The U.N. will host a meeting in Japan next month, at which countries are expected to agree on a series of 2020 targets to help battle the extinctions of plants and animals that help provide clean air and water, medicines and crops.

"Conservation resources are wasted searching for species that have no chance of rediscovery, while most missing species receive no attention," the authors told Reuters, pointing to efforts to try to find the Tasmanian tiger.

The last known living Tasmanian tiger died in 1936 in a zoo.  The tiger is a marsupial hunter the size of a dog.

Fisher told Reuters that there have been successful stories of rediscovering missing species of animals and plants.

However, he said that the rediscoveries barely make a dent in the rate of species loss overall.

"The number of additions every year outweighs the number of that have been rediscovered. There's still an accelerating rate of extinctions every year of mammals."


Image Caption: The last known Tasmanian tiger photographed at Hobart (formerly Beaumaris) Zoo in 1933.


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