September 10, 2010

Freshwater Turtle Population Facing Extinction

According to a new analysis by Conservation International (CI), freshwater turtles are in catastrophic decline.

The group says over a third of the estimated 280 species around the globe now face extinction.

The collection of turtles for food and to supply a lucrative pet trade are the main reasons for drivers behind the fall in numbers.

Another main concern for habitat loss is river damming for hydro-electricity.

Dr. Peter Paul van Dijk, the director of Conservation International's Tortoise and Freshwater Turtle Conservation Program, told BBC News the outlook was bleak.

"These are animals that take 15-20 years to reach maturity and then live for another 30-40 years, putting a clutch of eggs in the ground every year. They play the odds, hoping that in that 50-year lifetime, some of their hatchlings will somehow evade predators and go on to breed themselves."

"But if you take these animals out before they've reached 15 and can reproduce, it all ends there," he told BBC News.

Freshwater turtles adapt to live far up river systems, even into small foothill streams.  They populate lakes, rivers and estuaries.

However, the 11 families that comprise this collection of shelled creatures have seen the population drop drastically in the past two decades.

The turtles are highly prized throughout Asia, where their consumption is considered to have medicinal benefits.

On top of the exploitation of the turtles, some of their river habitats are being degraded.

"They need to have natural flow patterns in rivers otherwise their nests on the sandbank high up get flooded at the wrong time of year," van Dijk explained to BBC.

"They need clear water so they can see what they're eating. They need underwater plants, which can only grow if the water isn't too turbid. So, to some extent they can be seen as a proxy for the health of river systems."

The red river giant soft-shell turtle is the one turtle facing the most devastation.  There are only four reported individuals remaining alive in the world.

The red-crowned species was once widespread throughout the great rivers of northern India, Bangladesh and Nepal.  However, it has now been reduced to a single viable population in the "unholy" Chambal River of central India.

The Myanmar species' population is being built up for re-introduction program.

"All the tonnage of turtle that people want to consume can be satisfied by farming," van Dijk told BBC. "If we can eliminate the unsustainable collection from the wild, we have 80% of the battle won. Beyond that, it's a matter of habitat management for minimal impact on turtles and all the other wildlife in those habitats."


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