Hellström, G., Heynen, M., Borcherding, J. et al. 2016. Individual consistency and context dependence in group-size preference of Eurasian perch. Behavioural Processes 133, 6-11.
Many fish spend a large part of their life in groups. The size of the group influences potential costs and benefits of group living, and depending on context a fish may prefer different group sizes...