title: The effects of solar UV-B radiation on embryonic mortality and development in three boreal anurans (Rana temporaria, Rana arvalis and Bufo bufo).
abstract: Many species of amphibians have experienced population and range reductions. It has been hypothesized that sensitivity to UV-B may contribute to the population declines of some amphibian species. We performed field experiments to measure the effects of solar UV-B on the hatching success of three Finnish anuran species, the common frog (Rana temporaria), moor frog (Rana arvalis) and common toad (Bufo bufo). Further, the effects of natural UV-B radiation on survival of the tadpoles of the same three species of anurans were tested. A significant percentage of R. temporaria and B. bufo embryos survived when exposed to and protected from solar UV-B and hatching success was not affected by solar radiation. Elimination of solar UV-B significantly increased the hatching success of R. arvalis, but embryonic mortality was high in both treatments. The data indicates that under natural conditions, solar UV-B radiation influences embryo survival in R. arvalis, but has no effect on R. temporaria and B. bufo. Solar UV-B radiation had no effect on R. temporaria and R. arvalis tadpoles, but elimination of UV-B significantly increased survival of B. bufo tadpoles. It seems that ambient UV-radiation levels have no effect on R. temporaria but may affect R. arvalis and B. bufo at different developmental stages.
authors.affiliation: Department of Biology, University of Joensuu, Finland.
authors.forename: J
authors.initials: J
authors.lastname: Häkkinen
authors.forename: S
authors.initials: S
authors.lastname: Pasanen
authors.forename: J V
authors.initials: JV
authors.lastname: Kukkonen
mesh_terms: D000818:Animals; D002025:Bufonidae / Q000196:embryology*; D004781:Environmental Exposure; D007814:Larva / Q000254:growth & development; D011157:Population Dynamics; D011898:Ranidae / Q000196:embryology*; D016019:Survival Analysis; D014466:Ultraviolet Rays / Q000009:adverse effects*