Fish Behaviour: Determinants and Implications for Welfare

Abstract

This chapter starts by spelling out different ways of answering the question “why does an animal behave in this way?”, often referred to as Tinbergen’s four question (Tinbergen, N., The study of instinct. Clarendon Press, Oxford, 1951). These are: what causes the behaviour? How does it develop? What are its consequences for fitness? and Through what stages did it evolve? Examples of answers to these different questions are given in relation to the behaviour of wild fish, looking at: use of space; foraging and feeding; avoiding predators; aggression and fighting and courtship. Farmed fish are relatively little domestication compared to farmed terrestrial species and they bring with them to the fish farm many of the behavioural characteristics of farmed fish; this is discussed in the context of each of the broad behavioural systems mentioned above. Problems for the welfare of farmed fish arising from expression of the natural behaviour of the fish concerned are discussed and behaviourally-based solutions suggested.