Amphibian and reptile numbers fall by 75% in reserve meant to save them
Ian Sample, science correspondent
Tuesday April 17, 2007
The Guardian
A protected rainforest in one of the world's richest biodiversity hotspots has suffered an alarming collapse in amphibians and reptiles, suggesting such havens may fail to slow the creatures' slide towards global extinction.
Conservationists working in a lowland forest reserve at La Selva in Costa Rica used biological records dating from 1970 to show that species of frogs, toads, lizards, snakes and salamanders have plummeted on average 75% in the past 35 years.
Dramatic falls in amphibian and reptile numbers elsewhere in the world have been blamed on habitat destruction and the fungal disease chytridiomycosis, which has inflicted a devastating toll across central and South America. But scientists hoped many species would continue to thrive in dedicated reserves, where building, land-clearance and agricultural chemicals are banned.The new findings suggest an unknown ecological effect is behind at least some of the sudden losses and have prompted scientists to call for urgent studies in other protected forest areas. The researchers, led by Maureen Donelly at Florida International University, believe climate change has brought warmer, wetter weather to the refuge, with the knock-on effect of reducing the amount of leaf litter on the forest floor. Nearly all of the species rely on leaf litter to some extent, either using it for shelter, or feeding on insects that eat the leaves. (Read more...)
