A new University of Liverpool study has concluded that the anglers’ myth ‘that fish don’t feel pain’ can be dispelled: fish do indeed feel pain, with a similarity to that experienced by mammals including humans.

From hyper-ventilating and loss of appetite to long-term behavioural changes after a painful experience, the review by Dr Lynne Sneddon explores pain among fish and across the animal kingdom and explains its shared molecular foundations and the behaviours associated with avoiding and alleviating it.

Dr Lynne Sneddon, a biologist and one of the world’s leading experts on fish pain, said: “When subject to a potentially painful event fishes show adverse changes in behaviour such as suspension of feeding and reduced activity, which are prevented when a pain-relieving drug is provided.

“When the fish’s lips are given a painful stimulus they rub the mouth against the side of the tank much like we rub our toe when we stub it.

“If we accept fish experience pain, then this has important implications for how we treat them. Care should be taken when handling fish to avoid damaging their sensitive skin and they should be humanely caught and killed.”

The paper is published as part of ‘Evolution of mechanisms and behaviour important for pain’ – the latest theme issue of Philosophical Transactions of the Royal Society B that includes over a dozen articles on pain.

Research reference:

Sneddon Lynne U, Evolution of nociception and pain: evidence from fish models, 374, Phil. Trans. R. Soc. B, https://doi.org/10.1098/rstb.2019.0290