September 27, 2013
Rainforest Wildlife Impacted By Forest Shrinkage
April Flowers for redOrbit.com - Your Universe Online
An international team of scientists reveals that species living in rainforest fragments could be far more likely to disappear than was previously thought.
The scope of the two decade study, published in the journal Science, allowed the researchers to witness the near-complete extinction of native small mammals on forest islands created by a large hydroelectric reservoir in Thailand.
"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."
The findings have important implications because forests around the world are being rapidly felled and chopped up into small island-like fragments. "It's vital that we understand what happens to species in forest fragments," said Antony Lynam of the Wildlife Conservation Society. "The fate of much of the world's biodiversity is going to depend on it."
The research team wanted to understand how long species can live in forest fragments. If such species can persist for many decades, it gives conservationists time to create wildlife corridors or restore surrounding forests. This would reduce the harmful effects of forest isolation.
Unfortunately, the research team saw native small mammals vanish with alarming speed. After 25 years, only a handful remained - on average one individual per forest fragment. "Native mammals suffered the harmful effects of population isolation, and they also had to deal with a devastating invader – the Malayan field rat."
The invasive rat grew so abundant in just a few years on the islands that it virtually displaced all native small mammals. Although the rat normally favors villages and agricultural lands, it will also invade disturbed forests.
"This tells us that the double whammy of habitat fragmentation and invading species can be fatal for native wildlife," said Lynam. "And that's frightening because invaders are increasing in disturbed and fragmented habitats around the world."
"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."