Sovremennye ouspekhi v izoutchenii vnoutrividovoï khimitcheskoï kommounikatsii ou evropeïskogo sourka (Marmota marmota). Recent advances in the study of intraspecific chemical communication in alpine marmot (Marmota marmota) [Résultats actuels de l'étude de la communication intraspécifique chez la marmotte alpine].

Résumé

Scent marking by cheek-rubbing in the Alpine marmot was investigated from 1991 to 1996, in order to know more about the functional meaning of such a behaviour, and to understand the mechanism underlying the chemical communication of this species. First, field observations of animals individually marked were performed. Results showed that reproductive adult territorial residents scent mark their home range especially on main burrow defence. In a second part, our objectives were to find some reliable behaviours, performed by resident marmots, in response to foreign scent marks. Results indicated that the intensity of overmarking, as well as the time of sniffing were significant, and could from the bioassay. Then, using this response-guided strategy, we tested fractions of the marking substance in order to isolate the semiochemicals involved in the chemical communication. Field experiments showed that the biologically active fraction consisted in the total volatile fraction issued from the secretions of the orbital gland. The next step of the study was to identify the molecules entering the composition of this fraction: more the 30 compounds were detected in each individual sample. Thus, the hypothesis of the molecular complexity variability of chemical composition among individual samples is evaluated, and the link between this variability and social or physiological factors is discussed.