Effects of ultraviolet radiation on boreal toads in Colorado

Paul Stephen Corn

doi:10.1890/1051-0761(1998)008[0018:eourob]2.0.co;2

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Effects of ultraviolet radiation on boreal toads in Colorado

Paul Stephen Corn

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Abstract

Field exposures of Bufo boreas embryos to fractions of ambient UV-B radiation at two sites in Rocky Mountain National Park, Colorado, USA, were conducted to evaluate UV-B as a possible cause of recent severe declines of this species. There were no differences in hatching success of B. boreas embryos exposed to 0–100% of ambient UV-B radiation at either study site, results that are different from those of recent studies in Oregon that found increased mortality of B. boreas embryos exposed to ambient UV-B. The reasons for these differing results are not apparent, and several possible explanations exist, including differences in experimental design, presence or absence of a pathogenic fungus, and geographic genetic variation. Bufo boreas embryos were probably not receiving higher doses of UV-B radiation during the experiments in Oregon compared to the experiments in this study. Results of this study do not support UV-B radiation alone as the cause of the decline of B. boreas during the past 20 yr in the southern Rocky Mountains, but UV-B cannot be dismissed because of the contradictory results from other studies.

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Ecological Applications Article

Source-reported bounding extent: 40.46036107657892° to 40.529795379276266° latitude; -105.62445146660353° to -105.45353483423148° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

Paul Stephen Corn. 1998. Effects of ultraviolet radiation on boreal toads in Colorado. https://doi.org/10.1890/1051-0761(1998)008%5B0018%3Aeourob%5D2.0.co%3B2

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