Reproduction in the Checkered Garter Snake, Thamnophis marcianus, from Southern Texas and Northeastern Mexico: Seasonality and Evidence for Multiple Clutches

Abstract

Preserved and laboratory maintained specimens of the checkered garter snake, Thamnophis marcianus from southern Texas and northeastern Mexico were examined for their reproductive characteristics. Female T. marcianus undergo follicular vitellogenesis primarily in the spring, however, some reproduction occurs in late summer. The variability in parturition dates suggests that some females are producing a single clutch in midsummer, whereas others have their young in late spring and/or late fall. This suggests that T. marcianus may sometimes alternate between producing a single clutch in one year and producing two clutches the next year. Clutch size, clutch weight and size of young increased with size of the female. Hoever, relative clutch mass was not correlated to female size.