But they have no antidote to the virus, which last year wiped out whole colonies of frogs at more than 300 sites.
Hundreds of frogs can die within days of the first symptoms appearing, many in acute distress. Last summer the Frog Mortality Project - a partnership between pathologists at the Institute of Zoology and a private company, Herpetofauna Consultants International - was set up to study the phenomenon, and a public appeal for evidence brought a flood of heart-rending stories. 'I had people in tears on the telephone,' Tom Langton, an ecologist with HCI, said.
In the worst case, 500 were wiped out in a pond in Buckinghamshire. Deaths totalling 100 or more per site have become common, and scientists are considering a link with pollution. They say there is a world- wide decline in amphibians. In Tasmania, for instance, an entire species of frog has become extinct in recent years.
The scientists studied the corpses of 50 frogs gathered from garden ponds. The virus was found in 48.
The Frog Mortality Project can be contacted at PO Box 1, Halesworth, Suffolk, IP19 9AE.Reuse content