The role of familiarity in shelter site fidelity: insights from a mesocosm experiment with a plethodontid salamander

Behavioral adaptation is one of the first responses put in play by individuals to buffer environmental variations and to maintain homeostatic equilibrium with their environment. Microhabitat selection is pivotal for maximizing fitness, survival and reproduction, but how individuals process and exploit information acquired from the environment to make future microhabitat choice is yet understudied. In this study, we used outdoor mesocosms in which we introduced Strinati’s cave salamanders (Speleomantes strinatii), to assess their behavioral patterns of shelter site fidelity. In each mesocosm three microhabitats were available to the salamanders: the leaf litter, a log and a rock. A total of 22 salamanders were tested over an 8-day period, 11 in autumn and 11 in spring. Salamanders shelter site fidelity was driven by both microhabitat humidity and previous experience obtained in the mesocosm. In our experiment, the time spent in the mesocosm was the main factor influencing shelter site fidelity, suggesting that previous experience and familiarity are important in salamanders’ behavioral adaptation. Therefore, cave salamanders are capable of learning from experience when selecting their shelters, a behavior that could also be relevant during migration, colonization of new environments and adaptation to climate change.