The influence of body condition and prey availability on female breeding success in the smooth snake (Coronella austriaca Laurenti)

A study of individually marked smooth snakes Coronella austriaca was carried out in Wareham Forest, southern England between 1992 and 2001. On average, approximately one-third of potential breeding females reproduced each year and within this group, the proportion breeding was positively correlated with snout-vent length (SVL). Successful breeders had a higher than average body condition at the start of the breeding year compared with unsuccessful breeders. The density of gravid females was positively correlated with prey density in the breeding year but not in the year preceding it. No significant relationships were found between the density of non-breeding females and prey density in either the breeding year or the preceding year. Although most breeding females did not produce young in consecutive years, a small proportion did. There was a weak positive relationship between clutch size and female SVL. This study suggests that the potential for female smooth snakes to breed is provided by stored energy reserves but that this potential is regulated by prey availability in the breeding year.