Professor Culum Brown's (Macquarie University) presentation at E-Aquarium Conference 2021. For a long time, fishes have been considered as mindless automatons, but research on fish cognition over the past 20 years has greatly changed that view. All evidence suggest they are highly intelligent, sentient creatures. In 2002, the first evidence that fish had nociceptors (for detecting noxious stimuli) suggested that, like the rest of the vertebrates, they feel pain. Since that time there is mounting evidence that they do feel pain on an emotional level in a manner not dissimilar to humans.

However, since one cannot study emotions directly because “other mind” problem (it is subjective), scientists use multiple lines of indirect evidence that collectively show that animals respond aversively to painful stimuli (the signs and symptoms). Sneddon (2014) lists 17 criteria which collectively point to the capacity for pain and suffering in animals. Here I briefly outline what these criteria are and determine how many have been met by researchers studying fish pain. Some of these criteria a more closely linked to the nociceptor component of pain, while others are key indicators of conscious/emotional responses to pain, far beyond mere reflexes.