The impact of the discovery of the first instance of amphibian population decline due to the Chytrid fungus in Europe

Jaime Bosch, Iñigo Martínez-Solano and Mario García-París

Museo Nacional de Ciencias Naturales, CSIC. Madrid. Spain

A Chytrid fungus, a pathogen which has been causally related to amphibian population declines worldwide, is in the wild in Europe. The problem arose in the summer of 1997 when thousand of post-metamorphic common midwife toads (Alytes obstetricans) were found dead across the Peñalara Natural Park, a protected area in Central Spain at high altitude and very close to Madrid. Mass mortality episodes occurred again in the summers of 1998 and 1999. This latter year we studied the problem and were able to identify its cause. Just one species had been affected, while the other nine amphibian species present in the Park remained apparently unaffected.

We got a quick response to the problem from the authorities of the Natural Park, which supported our research. In addition, several newspapers, magazines, TV, and radio stations divulged the news in Spain. However, after an initial period of general concern, the problem lost interest probably because no real and efficient solutions could be tackled.

The affected species are patchily distributed in Central Spain, populations being largely isolated from each other, so recolonization of the area might be very difficult if extinction finally takes place. At present, we are studying the possibility of initiating a breeding program in semi-natural conditions, with public funds, by using healthy individuals captured in the area before the problem arose. In addition, an ambitious project for studying the conservation status of every amphibian population around the affected area is now under evaluation. Any initiative generated from this event will be probably considered by the Spanish conservation authorities.