The Herpetological Journal

pp.145-148

Authors: Florentino Braña, Luis Frechilla And Germán Orizaola

Abstract: We have analyzed the effect of introduced fish on amphibian assemblages in mountain lakes of the Cantabrian range (Asturias and León; northern Spain), by comparing amphibian species richness, abundance and diversity in lakes occupied by introduced fish and in those without fish. Amphibian species numbers were significantly lower in lakes inhabited by fish, both considering the absolute number and the values corrected for the effect of the main correlates of the species richness (shore extent and altitude). Amphibian abundance (all species and stages pooled) and diversity also tended to be lower in lakes inhabited by fish as compared with the fishless ones. Direct predation by fish, for which we present evidence in our studied lakes, is likely to be the main cause for the reported amphibian depletion, although recognition by adult amphibians of chemical cues from predatory fish and subsequent avoidance of habitats with fish for reproduction could also be contributory.