Long-term United Kingdom trends in the breeding phenology of the Common Frog, Rana temporaria

Many of the early indications of climate change detected in the United Kingdom have been changes in phenology and in particular the early occurrence of key biological events. Significant trends toward earlier breeding have been found in recent decades in most amphibian species in the United Kingdom, one notable exception being the Common Frog, Rana temporaria. We examine data for this species from the United Kingdom's Environmental Change Network for trends in breeding timing. Significant trends toward earlier congregation and spawning were found but not earlier hatching. The observed trends are strongly associated with climate, especially temperature.