Effects of ambient UV-B radiation on early development of the common frog (Rana temporaria) embryos in the subarctic

Several recent field experiments have demonstrated that ambient ultraviolet -B radiation (UV-B; 280-315 nm) may cause severe mortality of amphibian emb ryos. We investigated the effects of ambient UV-B on early embryonic perfor mance of the common frog (Rana temporaria) in subarctic Finland (ca. 69 deg rees 03'N, 20 degrees 50'E), where levels of UV-B radiation during the egg laying period are roughly twice as high as those in southern Fennoscandia. We found no evidence for decreased embryonic mortality, decreased frequency of developmental anomalies or improved growth performance of embryos shiel ded from UV-8 as compared with embryos exposed to ambient levels of UV-B. O ur results concur with the results of earlier studies with this species con ducted in more southern populations, and suggest that current W-B levels al one are not likely to pose significant threat for the well being of subarct ic common frog populations.