Experimental study of dispersal behavior in the Common Wall Lizard, Podarcis muralis (LAURENTI, 1768)

Ecological aspects of the dispersal behavior of Common Wall Lizards, Podarcis muralis (LAURENTI, 1768), were studied under the short-term effects of population density and individual body condition. The individual dispersal attitude was assessed by comparing emigration rates between two alternative scenarios of (i) moderate starting density (augmentation design) and (ii) high starting density (colonization design). The study system consisted of two interconnected seminatural enclosures simulating two habitat patches linked by corridors. The study revealed that the dispersal activity in the study species was influenced by the starting lizard density in the enclosures. The study species showed no dispersal behavior in the augmentation design and a density-dependent pattern in the colonization design. Moreover, males moved more frequently between enclosures than females, whereas neither sex nor body condition influenced the dispersal rate. Podarcis muralis showed behavioral similarity with P siculus (RAFINESQUE-SCHMALTZ, 1810), although for this latter species dispersion rate was found to be higher and movements between enclosures to start at lower population densities. Unlike P. siculus, muralis exhibited different dispersal behavior at opposite density conditions: the lizards moved away from enclosures both highly crowded and unpopulated by conspecifics, i.e., avoided to stay longer in initially empty than in occupied enclosures.