An invading horde of hungry octopuses from the Mediterranean is decimating crab fisheries in British waters.

Shellfish wholesalers say the huge influx has resulted in swingeing cuts to restaurant orders, leaving chefs scrambling to keep their kitchens stocked.

The canny octopuses, thought to have been lured north in their thousands by unusually warm UK waters, have learned to raid fishermen's pots through a small 'escape hatch' – designed to allow juvenile crabs and lobsters to crawl free.

And while they will dine on all shellfish, crab is considered their favourite prey.

The owner of one Devon boat, Brian Tapper, of Plymouth, said: 'The octopuses are ruining us.