It's probably not something you want to be thinking about when you're ordering dinner from the seafood menu, knowing full well that any crustacean that you choose will likely be plucked life from the water and immediately dropped into a boiling pot. I've enjoyed many an episode of The Deadliest Catch over the past few years, and although I have voiced a thought or two about how the crabs stuffed into the ship's tanks can't be very comfortable, I have to admit that I haven't given it too much thought after that.
However, this new study, by Barry Magee and Robert Greenwood, of Queen's University in Belfast, UK, may provide proof that crustaceans do feel pain.
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According to the article in The Guardian, the researchers tested a group of 90 shore crabs, placing them in a brightly lit tank with various shelters at the bottom. They waited until the crabs followed their natural instinct — to hide in the shadow of rocky shelters to avoid predators — and then randomly produced a mild electric shock under one of the shelters. The shocked crabs immediately scattered out into the open, some of them choosing other shelter and some of them retreating back to where they were. A second shock was produced under the same shelter, causing the crabs to scatter again, but after this second time, only a small number of the crabs chose the same shelter. The rest all went to other non-shocking shelters.
According to Professor Greenwood, this result demonstrates classic shock avoidance by 'discrimination learning', which is seen in all species that are capable of feeling pain. The avoidance of the electric shocks so quickly shows that the crabs were able to perceive the pain of the shocks and avoid the harm by choosing another shelter. If it was just a reflex reaction to stimuli, the crabs would have just, again and again, gone right back to the same shelter they were just shocked out from under.
With the many regulations in place now to help ensure that the other animals we use for food are treated in a humane way, if this study turns out to be correct, how will the seafood industry be affected. Crabs caught for market are routinely stuffed into cramped ship tanks, with barely any room to move, and entire catches have suffocated before they can get back to port.
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"Crabs in some fisheries around the world have their claws just torn off and the live animals are thrown back into the sea – because it's only the claws that are required by fisherman," said Elwood. "You have lobsters being processed, prawns that are being processed live by the front end, the head and the thorax being torn off. And the head with the brain will carrying on being a viable nervous system and will continue to go on like that for an hour or so."
There is still some debate about the issue, of course, however as Elwood points out: "Even if there's a slight chance they feel pain, I feel we should start attending to that now."
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