Swedish researchers have confirmed that crabs, and likely other crustaceans, experience pain, challenging long-held assumptions about these animals’ capacity for suffering.
While previous studies suggested that crustaceans might feel pain, this is the first to include EEG-style measurements, which detected pain signals being transmitted to the brains of shore crabs during chemical and mechanical stimulation.
Published in Biology, the study highlights the ethical implications for the treatment of decapod crustaceans, whose ability to feel pain has often been debated. Lead author Eleftherios Kasiouras from the University of Gothenburg emphasized that the findings could inform better welfare practices.
He also pointed out that species like lobsters and shrimp, which share similar nervous system structures with crabs, likely experience pain as well.
This research is particularly significant because crustaceans like crabs, lobsters, and shrimp are not currently covered by EU animal welfare legislation. Many are subjected to inhumane practices such as being boiled alive, with no legal protections in place.
According to Kasiouras, “All animals need a pain system to survive by avoiding danger. Given the similarities in nervous systems, we can assume that other crustaceans, including shrimp, crayfish, and lobsters, respond similarly to painful stimuli.”
The study arrives amidst a growing awareness of animal sentience. In the UK, the 2021 Animal Sentience Bill recognized crustaceans and cephalopods as sentient beings capable of experiencing feelings.
However, the lack of enforcement means cruel practices, like boiling these creatures alive, persist despite their recognized sentience.
Globally, up to 580 billion farmed crustaceans, including crabs, lobsters, prawns, and shrimp, are killed each year. Advocates argue that this staggering number underscores the need for immediate legal protections.
Yet, the research raises ethical concerns about how pain studies themselves are conducted, as they inherently involve exposing animals to discomfort.
Critics also point out that there may already be sufficient evidence to warrant protective measures for crustaceans without additional testing. Decades of research on pain responses in crabs and related species have consistently demonstrated their capacity for suffering.
Even with scientific evidence and official recognition of crustaceans’ sentience, meaningful legislative changes remain uncertain. For many animal advocates, the solution lies beyond regulation.
They argue that the only ethical choice is to abstain from consuming crustaceans and other animals altogether, as there may be no truly humane way to farm and kill sentient beings.