Behaviour 2019
Hatching time and embryonic learning in fathead minnows
Marianna E Horn, Douglas P Chivers. University of Saskatchewan, Saskatoon, SK, Canada

When faced with predation risk, animals may avoid foraging or miss mating opportunities. Because these lost opportunities come at a cost, an organism will benefit from the ability to evaluate the risk involved when it encounters potential predators. As animals grow, they may move through different prey guilds, and recognizing the ontogeny of injured conspecifics can help them to evaluate the relevance of a threat. We exposed embryonic minnows to different concentrations of injury-released alarm cues collected from adult minnows combined with predator odour. Previous research has shown that minnows can hatch early in response to embryonic alarm cues, but our minnows did not hatch early in response to adult cues. However, these same individuals learned from these exposure events and subsequently demonstrated a fright response to predator odour. Additionally, the intensity of their fright responses was correlated with the degree of threat as represented by the concentration of the alarm cue, with a shift in antipredator behaviour at the highest threat level.