According to the OIE, World Organisation of Animal Health, “an animal is in a good state of welfare if (as indicated by scientific evidence) it is healthy, comfortable, well nourished, safe, able to express innate behavior, and it is not suffering from unpleasant states such as pain, fear and distress […]’’. The question of whether fish are able to experience such states of physical and mental discomfort has been raised many times. It has been shown that some species of fish are able to pass the mark test, indicating that they have a higher level of self-awareness than has been attributed to them for a long time. Moreover, despite the fact that they do not possess a neocortex, the brain region that is associated with conscious awareness in other species, teleost fish fulfill all criteria generally used to determine both consciousness and the ability to feel pain. The animation advocates for the ethical treatment of fish, challenging their exhibition within small or inappropriate aquaria for mere entertainment.
Sources: “Introduction to the recommendations for animal welfare”, OIE (World Organisation of Animal Health), Terrestrial animal health code, (2010).
Kohda, Masanori et al. “If a fish can pass the mark test, what are the implications for consciousness and self-awareness testing in animals?” PLOS Biology, (2019).
Yue Cottee, S. “Are fish the victims of ‘speciesism’? A discussion about fear, pain and animal consciousness” Fish Physiology and Biochemistry, vol. 38, (2012): 5–15.