Understanding Shellfish Molting

Shellfish molt to grow larger, shedding their exoskeletons. This process, called ecdysis, is vital for their development. Unlike humans, shellfish must discard their rigid homes to expand.

Molting is initiated by environmental cues and hormones. As shellfish grow, hormonal changes trigger the development of a new, soft shell beneath their current one.

Before molting, shellfish reabsorb some minerals from their old shell. They may also ingest more calcium to prepare for the formation of a new, larger shell after molting.

During ecdysis, shellfish secrete enzymes to separate the old shell from the underlying skin. They then extract their body from the shell, which can be a vulnerable period for the creature.

Immediately after molting, shellfish are soft and defenseless until their new exoskeleton hardens. This period is critical, requiring them to hide from predators to survive.

Once the new shell hardens, the shellfish can resume normal activities. The soft shell expands before hardening, allowing room for future growth.

Young shellfish molt more frequently than adults due to their rapid growth. Some species can molt every few weeks, while older ones may only molt once or twice a year.

After molting, some crabs may eat their old exoskeleton to recycle minerals and nutrients.