Data for fish foraging and anti-predator escape behavior

Prior experience with predation risk can provide valuable
information and influence how prey animals trade off between food and
safety. We examine foraging and refuge use behavior among groups of social
goldfish (Carrasius auratus) at risk of predation from little egrets
(Egretta garzetta) for groups containing only individuals that previously
experienced predators, only naïve individuals, or mixed groups containing
both experienced and naïve fish. Groups of all-experienced fish consumed
significantly less food than the all-naïve and mixed groups, and spent the
least amount of time foraging outside of the refuge. Furthermore, within
the mixed treatment groups, naïve individuals spent more time foraging
compared to experienced group members. In terms of survival, the groups
containing all-naïve members experienced the highest mortality, and
significantly more naïve fish were captured within the mixed groups.
Interestingly, the mixed groups experienced overall mortality rates
similar to the less active all-experienced groups, even though the mixed
groups foraged more like the all-naïve groups. We found that the mixed
groups were able to detect the approaching predator significantly earlier
than the all-naïve groups, which may explain this result. Thus, we show
that naïve individuals within mixed groups did not reduce foraging
activity via social learning from experienced group members, but did
benefit from enhanced collective predator detection. This result
represents an interesting example of the benefit of sociality and living
in groups of individuals with different experiences.