Winter activity in a coastal population of Vipera aspis (Reptilia, Viperidae)

Winter activity patterns in a little coastal population of Vipera aspis (4 adult males, 3 adult females) have been studied during three winters using radiotracking. Most of studied specimens are mainly active, hiding just under leaves, moving from a refuge to another, covering up to 150 m. About 50% of snakes were active in the sun (29% of total days). Home ranges and core areas were similar between sexes, even if males attained at larger home ranges. Recorded home ranges were relatively large with respect to those presumed for the winter season, during which the reported activity is usually absent or reduced. Short and long displacements and movements were relatively higher and more frequent in males than in females. Favourable temperatures due to the geographic position and climatic situation of the area seemed the major stimulus for this asp viper population to be active.