Current issues in fish welfare

Human beings may affect the welfare of fish through fisheries, aquaculture and a number of other activities. There is no agreement on just how to we igh the concern for welfare of fish against the hum an interests involved, but ethical frameworks exist th at suggest how this might be approached. Different definitions of animal welfare focus on an animal's condition, on its subjective experience o f that condition and/or on whether it can lead a natu ral life. These provide different, legitimate, pers pectives, but the approach taken in this paper is to focus on welfare as the absence of suffering. An unresolved and controversial issue in discussion s about animal welfare is whether non-human animals exposed to adverse experiences such as physical injury or confinement experience what humans would call suffering. The neocortex, which in huma ns is an important part of the neural mechanism tha t generates the subjective experience of suffering, i s lacking in fish and non-mammalian animals, and it has been argued that its absence in fish indicates that fish cannot suffer. However, a strong alternative view is that complex animals with sophisticated behaviour, such as fish, probably have the capacity for suffer ing, though this may be different in degree and kind fro m the human experience of this state. Recent empirical studies support this view and show that painful stimuli are, at least, strongly avers ive to fish. Consequently, injury or experience of othe r harmful conditions is a cause for concern in term s of welfare of individual fish. There is also growing e vidence that fish can experience fear-like states a nd that they avoid situations in which they have experience d adverse conditions.