SPECIAL ISSUE: AMPHIBIAN DECLINES Diversity and Distributions (2003) 9, 123–140

Abstract. As part of an overall ‘biodiversity crisis’, many amphibian populations are in decline throughout the world. Numerous factors have contributed to these declines, including habitat destruction, pathogens, increasing ultraviolet (UV) radiation, introduced non-native species and contaminants. In this paper we review the contribution of increasing UV radiation and environmental contamination to the global decline of amphibian populations. Both UV radiation and environmental contaminants can affect amphibians at all life stages. Exposure to UV radiation and to certain contaminants can kill amphibians and induce sublethal affects in embryos, larvae and adults. Moreover, UV radi-ation and contaminants may interact with one another synergistically. Synergistic interactions of UV radiation with contaminants can enhance the detrimental effects of the contaminant and UV radiation. Key words. Amphibian population declines, biodiversity, chytridiomycosis ozone depletion, contaminants, fertilizers, heavy metals, PAHs, pathogens, pesticides Saprolegnia, toxic chemicals, UV-B radiation