Oviposition Preferences in Newts: Does Temperature Matter?

摘要

A female's decision where and when to place her eggs has important fitness consequences for her offspring. Although temperature is considered among the most relevant abiotic factors affecting female oviposition site choice in ectotherms, little is known about the relative importance of temperature cues in complex oviposition decisions. In this study, we examined female's oviposition choice under conflicting demands for temperature and embryo protection by studying oviposition behaviour in female alpine newts, Triturus alpestris, exposed to various thermal conditions and the availability of egg-wrapping vegetation. Females oviposited between 12.5 and 22.5pC in the aquatic thermal gradient (5-32.5pC) with the unrestricted availability of oviposition vegetation. The removal of the vegetation from predominantly chosen oviposition temperatures (15-20pC) induced egg-retention in most females. This suggests that both temperature and the presence of egg-wrapping vegetation play important roles in oviposition site choice of alpine newts.