Learned recognition of intraspecific predators in larval long-toed salamanders Ambystoma macrodactylum

Citation
El. Wildy et Ar. Blaustein, Learned recognition of intraspecific predators in larval long-toed salamanders Ambystoma macrodactylum, ETHOLOGY, 107(6), 2001, pp. 479-493
Citations number
41
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Animal Sciences","Neurosciences & Behavoir
Journal title
ETHOLOGY
ISSN journal
0179-1613 → ACNP
Volume
107
Issue
6
Year of publication
2001
Pages
479 - 493
Database
ISI
SICI code
0179-1613(200106)107:6<479:LROIPI>2.0.ZU;2-K
Abstract
The ability of prey to detect predators and respond accordingly is critical to their survival. The use of chemical cues by animals in predator detecti on has been widely documented. In many cases, predator recognition is facil itated by the release of alarm cues from conspecific victims. Alarm cues el icit anti-predator behavior in many species, which can reduce their risk of being attacked. It has been previously demonstrated that adult long-toed s alamanders, Ambystoma macrodactylum, exhibit an alarm response to chemical cues from injured conspecifics. However, whether this response exists in th e larval stage of this species and whether it is an innate or a learned con dition is unknown. In the current study, we examined the alarm response of naive (i.e. lab-reared) larval long-toed salamanders. We conducted a series of behavioral trials during which we quantified the level of activity and spatial avoidance of hungry and satiated focal larvae to water conditioned by an injured conspecific, a cannibal that had recently been fed a conspeci fic or a non-cannibal that was recently fed a diet of Tubifex worms. Focal larvae neither reduced their activity nor spatially avoided the area of the stimulus in either treatment when satiated, and exhibited increased activi ty towards the cannibal stimulus when hungry. We regard this latter behavio r as a feeding response. Together these results suggest that an antipredato r response to injured conspecifics and to cannibalistic conspecifics is abs ent in naive larvae. Previous studies have shown that experienced wild captured salamanders do s how a response to cannibalistic conspecifics. Therefore, we conducted an ad ditional experiment examining whether larvae can learn to exhibit antipreda tor behavior in response to cues from cannibalized conspecifics. We exposed larvae to visual, chemical and tactile cues of stimulus animals that were actively foraging on conspecifics (experienced) or a diet of Tubifex (naive treatment). In subsequent behavioral treatments, experienced larvae signif icantly reduced their activity compared to naive larvae in response to chem ical cues of cannibals that had recently consumed conspecifics. We suggest that this behavior is a response to alarm cues released by consumed conspec ifics that may have labeled the cannibal. Furthermore, over time, interacti ons with cannibals may cause potential prey larvae to learn to avoid cannib als regardless of their recent diet.