Are Litoria aurea eggs more sensitive to Ultraviolet-B radiation than eggs of sympatric L. peronii or L. dentata?

Global declines in amphibian populations in often pristine habitats have led to suggestions that a ubiquitous agent might be involved, such as increased Ultraviolet-B (280-320 nm) radiation due to ozone depletion. The Green and Golden Bell Frog Litoria aurea, has suffered marked population declines and is presently listed as an endangered species in New South Wales. The effect of UV-B levels on hatching success in L. aurea and two sympatric species which have stable populations (L. deniata and L. peronii was tested at two elevations (sea-level and 600 m) and under three UV-8 treatments: 1) unfiltered sunlight, 2) sunlight filtered for UV-8, and 3) sunlight filtered for smaller wavelengths. Hatching success was significantly higher under the UV-B blocking treatment than under the unfiltered treatment in a repeat experiment involving one L. autea spawn (p = 0.01 7), but was not significantly different in the primary experiment involving three L. aurea spawns (p = 0.749). There were no significant differences between elevations or interactions between treatment and elevation in any species. There was a significant difference in survival between species (p = 0.001). with 46% of L. aurea surviving vs 76% each of L. deniata and L. peronii. The lack of a coherent trend in hatching success suggests that UV-B irradiance is not affecting survival in the egg to tadpole stage of L. aurea.