Throughout your childhood, do you ever remember growing out of your clothes or shoes from the previous year? Many marine organisms grow out of their “clothes” too, but instead of going shopping and buying new ones, they are capable of shedding their old outer layers and growing it back to fit.
Animals like crabs and lobsters have hard outer shells that are called exoskeletons. As they grow, these crustaceans need to get rid of their exoskeleton that is too small and grow a new protective layer that is a bigger size. This process is called molting and it happens at different times of the year for different animals. California spiny lobsters usually molt only once a year during the autumn, while crabs molt a few times a year in their early stages and then less often as they age.
Photo Credit: http://www.aquariumofpacific.org
The California spiny lobster is pictured above. Notice the species does not have front claws for defense against predators, but they have spines on their exoskeleton instead.
This is the tail molt of a California spiny lobster.
After the molting process, the shell of the crustaceans are soft and do not fully harden until a few days later. The soft shell leaves the animal exposed to the harsh elements in its environment and defenseless against predators. Molting is not only for shedding a small shell, but also for getting rid of shells that may be damaged or teeming with bacteria and harmful parasites.
Written By: Kenzie Richards
