A lobster thrown live into boiling water may suffer for many seconds, said a scientist who argued Thursday that crustaceans can likely feel pain.

A set of experiments on crabs revealed that the animals are willing to give up a valuable dark hiding place in order to avoid an electric shock, an indicator of pain, said a study in the Journal of Experimental Biology.

Crabs in the study learned to avoid the shelter in a laboratory tank where they had repeatedly received a shock, said study leader Bob Elwood of Queen's University in Belfast.

"They were willing to give up their hideaway in order to avoid the source of their probable pain."

Elwood told AFP it was impossible to prove beyond doubt that the animals feel pain, but the research results were "consistent" with pain and added: "Perhaps we should err on the side of caution".

Elwood said billions of prawns, crabs and lobster are caught or reared for human consumption every year and treated in "very extreme ways."

"Crabs have their claws torn off and the live crab is thrown back in the sea. Lobsters and prawns have the front half of the body torn off from the abdomen which is kept for the meat. The nervous system in the head and thorax is still functional an hour later."

The biologist said many people assumed that because crustaceans do not have a brain resembling that of vertebrate animals, they could not feel pain.

"Crustaceans are invertebrates and people do not care about invertebrates," he said.

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