Department of Integrative Biology

Chemical alarm cues are known to be important in mediating predator avoidance in a variety of taxonomic groups. The purpose of this study was to rest whether three species of salamanders that co-occur in the coastal mountains of Oregon utilize chemical alarm cues in predator avoidance. In laboratory experiments, Western redback salamanders, Plethodon vebiculum, and Southern torrent salamanders, Rhyacotriton variegatus, exhibited an avoidance response to stimuli from injured conspecifics, while Dunn's salamanders, Plethodon dunni did not. Additional experiments demonstrated interspecific alarm responses. P. vehiculum and R. variegatus responded to each other's alarm cues bur did not respond to the alarm cues of allotopic long-toed salamanders, Ambystoma macrodactylum. For R. variegatus this is despite the fact that they are more closely related to the allotopic species (A. macrodactylum) than to the syntopic species (P. vebiculum). Thus phylogeny alone may not explain patterns of cross-species alarm responses. Instead, interspecific alarm responses may occur between syntopic species that belong to the same prey guild (i.e. those species that co-occur spatially and temporally and are exposed to the same suite of predators).