Does the presence of conspecifics facilitate exploratory behaviour in a cichlid fish (Etroplus suratensis)?

Animals confronted with any kind of novelty show behavioural responses driven by avoidance and exploration. The expression of both tendencies is modulated by anxiety. Especially in group -living animals, the presence of conspecifics can reduce anxiety in novel situations and hence increase exploratory tendency. Such intensified behavioural responses triggered by the social envi-ronment of an individual are called social facilitation. Here, we tested for social facilitation on the exploratory tendency of group-living juvenile Green chromide cichlid fish (Etroplus suratensis) by assessing each individual twice in an open field test: once alone and once together with a conspe-cific. Contrary to our expectations, we found no difference in exploratory behaviour between the groups. However, our results suggest that changes in exploratory tendency across the two treat-ments were highly individual, both in extent and direction, and are likely driven by the presence of the conspecific and the focal individual's own behavioural type.