Study finds crabs ‘probably feel pain’

The Queen’s University Belfast study looked at the reaction of common shore crabs to small electric shocks. The crustaceans were willing to sacrifice a dark shelter to avoid further jolts, Professor Bob Elwood said.

He warned the food and aquaculture industries should reconsider how they treat live seafood like crabs, prawns and lobsters.

The expert said: “In contrast to mammals, crustaceans are given little or no protection as the presumption is that they cannot experience pain. Our research suggests otherwise.

“More consideration of the treatment of these animals is needed as a potentially very large problem is being ignored.”

The Northern Ireland research was published in the Journal of Experimental Biology.

One way to cook crabs is to plunge them into boiling water on the assumption that they do not feel pain, although many modern chefs stun them first. Prof Elwood said their welfare should be considered.

The Queen’s University experiment was designed to distinguish between pain and a reflex reaction. It showed that shore crabs were willing to trade something of value to them, in this case a dark shelter, to avoid future electric shock.

A total of 90 crabs were put individually in a tank with two dark shelters and some were shocked after they chose one. This process was repeated and by the third time most shocked crabs went to the alternative safe shelter.

Prof Elwood added: “Having experienced two rounds of shocks the crabs learned to avoid the shelter where they received the shock. They were willing to give up their hideaway in order to avoid the source of their probable pain.”

He said his research highlighted the need to investigate how crustaceans used in food industries are treated. He said the data results were consistent with the idea of pain. “Thus we conclude that there is a strong probability of pain and the need to consider the welfare of these animals.”