Why it matters
Molting controls growth rate, seasonal softness, reproductive timing, and predator risk. It also affects when lobsters are most vulnerable to warming, disease, and handling stress.
Molting (Ecdysis)
The process by which a lobster sheds its hard outer shell, absorbs water, and hardens a new, larger shell.
Definition
Molting, also called ecdysis, is how lobsters grow. They split the old shell, crawl out, swell to a larger size, and harden a new exoskeleton.
Conservation impact
NOAA notes that lobsters molt roughly 20 to 25 times before reaching the minimum harvest size. Because newly molted lobsters are soft-shelled and stressed, changing temperatures can alter both fishery timing and survival.
Quick facts
- Growth mechanism
- Only way lobsters increase size
- Early-life molts
- Roughly 20 to 25 molts in 5 to 8 years
- Conservation link
- Soft-shell periods increase stress and predation risk
Related reading
Climate Change and Lobster Migration: How Warming Oceans Are Reshaping Populations
As the Gulf of Maine warms at three times the global ocean average, American lobster populations are undergoing dramatic geographic shifts. GMRI's 2024 data shows the region recorded its 12th-warmest year, with scientists now predicting populations will decline to early 2000s levels within 30 years. Here is what the science says.