Retention of acquired predator recognition among shy versus bold juvenile rainbow trout
The ability to acquire information about predators allows prey to better balance threat-sensitive tradeoffs by responding only to ecologically relevant predation threats. However, predation risk is highly variable through time and responding to predators that no longer represent a threat would likely prove costly to prey. While a wealth of studies have examined the way in which prey learn, little attention has been paid to retention of acquired information. Recent studies suggest that retention is indeed plastic and shaped by a suite of intrinsic factors such as strength of initial conditioning and individual growth rate. Here, we investigated if the duration of retention of acquired information is influenced by individual behavioral tactics (i.e., ‘personality’). We recorded latency to escape an opaque acclimation chamber of juvenile rainbow trout (Oncorhynchus mykiss) as a measure of behavioral tactic. We then immediately conditioned individual trout to recognize pumpkinseed (Lepomis gibbosus) and tested for recognition 24 h or 8 days postconditioning. Our results demonstrate that while shy versus bold trout exhibited no difference in the strength of conditioned response to pumpkinseed odor during conditioning trials or when tested for recognition 24 h postconditioning, there was a significant effect of individual behavioral tactic on the retention of learned predator recognition. While shy trout continued to exhibit a learned response to pumpkinseed odor when tested 8 days postconditioning, bold trout were not different from our pseudoconditioned controls. These data suggest that the behavioral tactic employed at the time of conditioning influences the ‘memory window’ of acquired information.
KeywordsAcquired predator recognition Memory window Threat sensitivity Learning Rainbow trout Oncorhynchus mykiss
- Brown GE, Chivers DP (2005) Learning as an adaptive response to predation. In: Barbosa P, Castellanos I (eds) Ecology of predator–prey interactions. Oxford University Press, Oxford, pp 34–54Google Scholar
- Chivers DP, Smith RJF (1998) Chemical alarm signaling in aquatic predator–prey systems: a review and prospectus. Ecoscience 5:338–352Google Scholar
- Dugatkin LA, Godin J-GJ (1992) Prey approaching predators: a cost–benefit perspective. Ann Zool Fenn 29:233–252Google Scholar
- Lima SL, Steury TD (2005) Perception of predation risk. In: Barbosa P, Castellanos I (eds) Ecology of predator–prey interactions. Oxford University Press, Oxford, pp 166–188Google Scholar
- Vavrek MA, Brown GE (2009) Threat-sensitive responses to disturbance cues in juvenile convict cichlids and rainbow trout. Ann Zool Fenn 46:171–180Google Scholar