Competitor Assessment and Area Defense by Territorial Salamanders

Abstract

viously marked by a nonresident conspecific male. We found that intruders approached residents in both conditions, that residents resorted to significantly more threat behavior and significantly more nose-tapping (scent-mark sampling) in condition 1, and that intruders significantly increased their rates of gular pumping (sampling air-borne odors?) in condition 1. From the results of this and previous experiments, we pose a preliminary hypothesis for the function of territorial scent marks by P. cinereus. Such scent marks have little effect on repelling or intimidating intruders. They are important to the resident in identifying his defended area, provide information to intruders about the status (e.g., size) of the resident, and probably allow the intruder to identify correctly the resident (as compared to other simultaneous intruders). Thus, scent marking appears to function primarily in providing information to both resident and intruder that can be used in their decisions con