Mammal species living in rainforest fragments are likely to become extinct faster than previously believed, researchers of a new study found.
Nearly a decade ago, the government of Thailand launched a huge, unplanned experiment. They built a dam across the Khlong Saeng river, creating a 60-square-mile reservoir. As the Chiew Larn reservoir rose it drowned the river valley transforming 150 forested hilltops into islands, each with its own isolated menagerie of wildlife.
Previously, researchers have established that fragmenting wilderness can lead to the extinction of certain species but the rate of this extinction remained unknown, up until now. A team of international scientists from the National University of Singapore found that certain mammal species living in rainforest fragments are likely to become extinct faster than previously believed.
"It was like ecological Armageddon," said Luke Gibson from the National University of Singapore, who led the study. "Nobody imagined we'd see such catastrophic local extinctions."
Researchers noted that native small mammals vanished with alarming speed. They found that some small mammal species on forest islands became extinct in just five years.
"Our study focused on small mammals, but what we did not report was a similar near-complete extinction of medium to large-sized mammals, such as elephants, tigers and tapirs, which are now completely absent from these islands in the reservoir," Gibson told BBC news. "All of these animals were all in the forest landscape before the creation of the reservoir."
The findings of this study hold utmost importance, especially in an era when forests trees are being felled and chopped and deforestation has become a common phenomenon.
Gibson revealed that the inspiration to conduct this study came from his desire to learn how long certain mammal species could survive in fragmented forests. This can help ecologists determine the window of time they have to create wildlife corridors or restore surrounding forests to reduce the harmful effects of forest isolation.
"The bottom line is that we must conserve large, intact habitats for nature," said Gibson. "That's the only way we can ensure biodiversity will survive."
