Crabs feel pain from mild electrical shocks
The food and aquaculture industries should reconsider how they treat live crustaceans such as crabs, prawns and lobsters as they are likely to feel pain, a study has revealed.
The latest study by Professor Bob Elwood and Barry Magee from Queen's School of Biological Sciences looked at the reactions of common shore crabs to small electrical shocks, and their behaviour after experiencing those shocks.
Professor Elwood's previous research showed that prawns and hermit crabs respond in a way consistent with pain. This latest study provides further evidence of this.
"The experiment was carefully designed to distinguish between pain and a reflex phenomenon known as nociception. The function of pain is to aid future avoidance of the pain source, whereas nociception enables a reflex response that provides immediate protection but no awareness or changes to long-term behaviour," Professor Elwood said.
"While nociception is generally accepted to exist in virtually all animals the same is not true of pain. In particular, whether or not crustaceans experience pain remains widely debated," he said.
This latest study showed that shore crabs are willing to trade something of value to them and #65533; in this case a dark shelter and #65533; to avoid future electric shock.
Explaining how the experiment worked, Professor Elwood said: "Crabs value dark hideaways beneath rocks where they can shelter from predators. Exploiting this preference, our study tested whether the crabs experienced pain by seeing if they could learn to give up a valued dark hiding place in order to avoid a mild electric shock."
The research has been published in the Journal of Experimental Biology.