Zur Biometrie und zum Parasitenbefall von Zauneidechsen-Populationen der Region Halle-Leipzig (Lacerta agilis)

Abstract

From March to October in 2007 and 2008, a population of sand lizards (Lacerta agilis) at the south-western edge of the Dölauer Heide (Halle/Saale) and three other populations in the area of Halle and Leipzig were examined. During this study, biometric data and tick infestation of 165 sand lizards were analyzed.From all study sites, the population at the south-western edge of the Dölauer Heide possessed the largest number of individuals. Over all populations, the biometric data pointed out, that one third of all sampled animals lost their tail at least once. While in the reference populations, the proportion of autotomized individuals between sexes did not drift so far apart, the proportion of autotomized males in the population at the south-western edge of the Dölauer Heide laid well below that of autotomized females. Both successful predation and displacement of due to autotomy disadvantaged males might have led to this phenomenon. The adult animals with the largest snout-vent length and BCI values were found at the south-western edge of the Dölauer Heide. This could be an indicator that in this population also relatively old animals can be found, taking into consideration that an age estimation of adult sand lizards on the basis of biometric factors proves to be difficult. Across all populations a relatively high tick infestation rate (Ixodes ricinus) was observed, with slightly more males parasitized than females.Furthermore, it became evident that biometric data, in particular tick infestation and body condition index, can be significantly influenced by the time of sampling during the course of the year.