During the first year Alaskan king crabs hide in crevices formed by rocks or kelp forests to avoid predation. From the ages of 1 to 4 Alaskan king crabs form clusters of up to 500,000 individuals called pods. The pods disperse only for feeding. This behavior is thought to be used for protection during molting, when a crab is most vulnerable. The adult Alaskan king crabs have few predators because of their heavily armored and bumpy carapace. Carcinonemertes (nemertean worms) feed on eggs while mother is incubating. Erimacrus isenbeckii (Korean hair crab), Enhydra lutris (sea otters), and Heimlepidotus or Myoxocephalus (sculpins) are possible predators for adults.