crabCrab experts are calling for better protection for crustaceans caught or reared for the food industry after using electric shocks to prove that the creatures both feel and remember pain.

The study, carried out by experts at Queen’s University in Belfast, used shells wired up to deliver small shocks to test the responses of hermit crabs, which have no shell of their own and live in the discarded shells of other molluscs, as they attempted to crawl inside.

The crabs were then offered alternative shells. The researchers discovered that crabs which had received shocks were more likely to exchange their old shells for the new ones.

Professor Bob Elwood, who led the study, said this suggested that the crustaceans remembered the experience of the shock and were looking to “move house”.

“There has been a long debate about whether crustaceans including crabs, prawns and lobsters feel pain,” Elwood said.

“We know from previous research that they can detect harmful stimuli and withdraw from the source of the stimuli but that could be a simple reflex without the inner ‘feeling’ of unpleasantness that we associate with pain.

“This research demonstrates that it is not a simple reflex but that crabs trade off their need for a quality shell with the need to avoid the harmful stimulus.

Professor Elwood explained that while such trade-offs have been seen in vertebrates, this is the first study to have demonstrated this type of trade-off in crustaceans.
He added that this indicated protection was needed for crustaceans involved in the food industry.

“More research is needed in this area where a potentially very large problem is being ignored,” said Elwood.

“Legislation to protect crustaceans has been proposed but it is likely to cover only scientific research. Millions of crustacean are caught or reared in aquaculture for the food industry.

“With vertebrates we are asked to err on the side of caution and I believe this is the approach to take with these crustaceans.”

This entry was posted on Friday, March 27th, 2009 at 2:37 pm and is filed under Crustaceans, Ocean. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.