Intraspecific variation in the egg-wrapping behaviour of female smooth newts, Lissotriton vulgaris

Abstract

In many species of the Salamandridae family, females provide parental care by carefully wrapping plant material around their eggs. As this behaviour has been shown to have a large effect on offspring survival, variation in this trait is expected to be low. Detailed investigations are, however, lacking. In the present study, we analyzed the consistency of egg-wrapping behaviour in two time periods within a breeding season in female smooth newts (Lissotriton vulgaris). We found a surprisingly low proportion of wrapped eggs of around 47% during the first period (when males were present) and an almost doubled ratio of around 92% in the second period (when males were absent). Also, the variation between individuals was significantly lower in the second period than in the first one. Furthermore, the bigger the females were, the more the proportion of wrapped eggs increased day by day within the first period; however, this relationship did not fully explain the observed difference between the two periods. Our results suggest that parental care in smooth newts can be influenced by the presence of mating partners and body size, and provide the first empirical evidence for within-individual variation in egg-wrapping in a salamandrid species. © 2011 BRILL.