According to work published in the Journal of Experimental Biology, there is further evidence that crustaceans — crabs, lobsters, crayfish, shrimp and krill – experience pain. A study has revealed that the shore crab, a close relative of the species we use for food, responds to electric shocks and then goes on to avoid them. Earlier research shows that prawns and hermit crabs also react to pain.
Though there are currently no regulations to protect these animals, it’s time to reconsider our treatment of these beings. Some fisheries remove the claws of live crabs—claws that end up on our plates — before throwing them back.
Professor Bob Elwood of Queens University in Belfast: “You see these practices and you really do have to question whether they are reasonable… Even if you are reluctant to believe the data as being strongly suggestive [that the animals experience pain], is it worthwhile imposing this on billions of animals ever year throughout the world?”
He designed an experiment to assess how crustaceans respond to potentially painful situations:
“He looked at the European shore crab (Carcinus maenas) – a creature that usually takes shelter under dark rocks during the day to avoid being spotted and eaten by seagulls. The researchers placed the crabs in an arena and studied how the responded to electric shocks . Ninety crabs were individually placed in a brightly lit arena, and had the option of scuttling to two dark shelters. Once the creatures had taken refuge away from the light, half were given an electric shock in the first shelter they chose. The shocked crabs were then placed back into the tank again, but to the researchers’ surprise, most of them moved back to the original shelter where they had been stunned. Those that made this decision were then shocked a second time. But now the painful experience had an impact on their future behavior.”
Prof Elwood said: “Previously-shocked crabs were more likely to change shelters than crabs who hadn’t been shocked. Two experiences were enough to produce a significant behavioral change. “They leave what is a desired place — a dark shelter — to go out into this dangerous light environment — they are giving up something very valuable.”
The experiment was produced eight times. The result? Though there were no more shocks, the crustaceans continued to avoid the shelter where they had been shocked. For scientists, this was not merely a simple reflex action; the animals learned from their experience, and their experiences colored their future choices. Earlier work performed by this team also revealed that prawns and hermit crabs display behavior consistent pain perception.
A spokesperson for the European Food Safety Authority (EFSA) said that the organization had concluded that fish could feel pain, BUT, in the EU, decapods (a group that includes lobsters and crayfish) were not classified as sentient species. The subject of crustacean pain was “controversial” and a matter of interpretation, he said.
ref: BBC World Service
- Do Crabs Feel Pain? Maybe – and Maybe We Should Rethink Eating Them (science.time.com)