Facts: The Red King Crab

Red king crabs are decapod crustaceans that are closely related to hermit crabs. They are not true crabs. They are native to the northern Pacific Ocean. King crabs have 10 legs. The first pair of legs are claws. The right claw is usually the largest. The next three pairs are their walking legs. The fifth pair of legs are normally tucked underneath. Red king crabs can have a leg span of 5 ft. They are edible and harvested commercially. Their bodies are covered in sharp spines. King crabs are omnivores. They feed on a variety of organisms such as mollusk, other crabs, and fish. Smaller king crabs are eaten by many animals, such as fish, octopuses, and other king crabs. Red king crabs migrate to deeper water annually. They migrate back to shallower water to spawn. Female king crabs are smaller than males. Males and females are easy to tell apart. Males have a triangular abdominal flap and females have a rounded one. A female broods thousands of eggs under her tail flap. Females use their fifth pair of limbs to clean their eggs. The eggs develop for close to one year and hatch into swimming larvae in the spring. The larvae feed on plankton. Larval crabs go through several stages over a few months before settling on the bottom. The crabs must molt their shell to grow. They shed their shell by absorbing water and cracking the old shell. After molting, they are soft and vulnerable to predators until their new shell hardens. Adult females must molt in order to mate. Red king crab juveniles form pods by coming together and stacking on top of each other. This is believed to help the young crabs forage safely over a large area. The pods may be several feet high. Red king crabs are thought to live 20 to 30 years. Historically, they have been one of the most commercially important shellfish in Alaska. For more marine facts, click the SUBSCRIBE button!!