AVOIDANCE-RESPONSE OF A TERRESTRIAL SALAMANDER (AMBYSTOMA-MACRODACTYLUM) TO CHEMICAL ALARM CUES

Organisms from a wide variety of taxonomic groups possess chemical ala rm cues that are important in mediating predator avoidance. However, l ittle is known about the presence of such alarm cues in most amphibian s, and in particular terrestrial salamanders. In this study we tested whether adult long-toed salamanders (Ambystoma macrodactylum) showed a n avoidance response to stimuli from injured conspecifics. Avoidance o f stimuli from injured conspecifics could represent avoidance of a che mical alarm cue or, alternatively, avoidance of a territorial pheromon e or conspecific predator odor. Consequently, we also tested whether s alamanders avoided stimuli from noninjured conspecifics. Salamanders a voided stimuli from injured but not from noninjured conspecifics. Ther efore, we concluded that the response to injured conspecifics represen ts avoidance of a chemical alarm cue and not avoidance of a territoria l pheromone or predator cue. This is the first clear demonstration of chemical alarm signaling by a terrestrial amphibian and the first repo rt of chemical alarm signaling in an ambystomatid salamander. By avoid ing an area containing stimuli from injured conspecifics, long-toed sa lamanders may lower their risk of predation by avoiding areas where pr edators are foraging.