Current issues in fish welfare: Review paper
By F. A. Huntingford, C. Adams, V.A. Braithwaite, S. Kadri, T.G. Pottinger, P. Sandøe & J. F. Turnbull (2006)
Journal of fish biology. Wiley-Blackwell
Abstract
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 weigh the concern for welfare of fish against the human interests involved, but ethical frameworks exist that suggest how this might be approached.
Different definitions of animal welfare focus on an animals condition, on its subjective experience of that condition and/or on whether it can lead a natural life. These provide different, legitimate, perspectives, but the approach taken in this paper is to focus on welfare as the absence of suffering.
An unresolved and controversial issue in discussions 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 humans is an important part of the neural mechanism that generates the subjective experience of suffering, is 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 suffering, though this may be different in degree and kind from the human experience of this state.
Recent empirical studies support this view and show that painful stimuli are, at least, strongly aversive to fish. Consequently, injury or experience of other harmful conditions is a cause for concern in terms of welfare of individual fish. There is also growing evidence that fish can experience fear-like states and that they avoid situations in which they have experienced adverse conditions.
Current issues in fish welfare: Review paper (pdf)