The most obvious anti-predator adaptation is the development of massive chelipeds that are capable of exerting 14,000 pounds per square inch of pressure. These claws keep the number of adult stone crab predators to a minimum. The general consensus among experts in the study of Menippe mercenaria believe the low number of natural predators is probably due to the hard exoskeleton of the stone crab, which allows it to survive long enough to pinch and gash the predator's gastrointestinal lining. One species that seems completely unconcerned with the massive chelipeds of the stone crab is the octopus, which is the primary natural predator of the stone crab. Juvenile stone crabs are also depredated by large fish.