Farmed Fish Consciousness and Pain Research

The scientific understanding of fish consciousness and pain has advanced dramatically over the past two decades, significantly strengthening the case for fish welfare protections in aquaculture and wild capture fisheries.

Key Facts

The 2021 Cambridge Declaration on Consciousness, and subsequent updates, affirm that fish have the neurological substrates for conscious experience
Fish show nociception, avoidance learning, wound-directed behaviour, and motivational trade-offs consistent with pain experience
Opioid receptors in fish brain tissue respond to morphine and other analgesics, reducing pain-related behaviours
The trigeminal nerve in fish, when activated by bee venom injection, produces behavioural changes that naloxone (opioid antagonist) reverses
Fish have been shown to prefer environments associated with pain relief (analgesic-treated water) when in pain
Cognitive bias experiments in fish show pessimistic responses consistent with negative emotional states after aversive events
UK law (Animal Welfare Act 2006) covers fish as vertebrate animals, but specific provisions for fish welfare in aquaculture are limited
The Fish Welfare Initiative estimates that over 1 trillion wild-caught fish and hundreds of billions of farmed fish may suffer annually

Welfare Considerations

The scientific case for fish pain and consciousness has grown from contested to compelling over the past 20 years. Fish show all the behavioural hallmarks of pain experience: avoidance, wound-directed behaviour, analgesic preference, and cognitive bias. The neurological substrates differ from mammals but the functional outcomes are similar. This matters enormously given the scale of fish farming and fishing - the numbers involved are orders of magnitude larger than all terrestrial animal agriculture combined. Despite this, fish welfare protections in most jurisdictions remain far weaker than for vertebrate land animals. Bringing fish welfare law and practice into alignment with the science is one of the most important and tractable improvements available in animal welfare policy.

What You Can Do

Engage with UK government fisheries policy to advocate for mandatory stunning before slaughter of farmed fish
Support the Fish Welfare Initiative and Fishcount organisations working on wild and farmed fish welfare
Choose sustainably and humanely certified fish products that specify pre-slaughter stunning
Reduce fish consumption and shift to certified higher welfare alternatives
Advocate for fish to receive the same legal welfare protections as other vertebrates in aquaculture regulation
Share evidence of fish consciousness with others to shift public and policy understanding