Scientist tracks crabs with fake limpets

Scientists have a new weapon in their efforts to study the struggle for survival on Britain's shoreline - a wax limpet. Richard Thompson, a marine ecologist at the University of Southampton, created the bogus shellfish to study the hunting strategies of crabs.

In the Journal of the Marine Biological Association of the UK, Dr Thompson describes how replica limpets, fashioned from dental modelling wax and screwed into inter-tidal rocks, tempted hungry crabs to leave deep claw marks to record each encounter. His ingenious study revealed that crabs from different places tended to hunt at different times and that they relied on sight to locate their prey.