Lobsters are integral parts of marine food webs and are subject to predation. Their tough exterior provides protection, but various marine animals hunt them throughout their life stages.
Key Predators of Lobsters
Lobsters face many predators, with vulnerability depending on their life stage and physical condition. Larval and juvenile lobsters are particularly susceptible, as their small size and softer bodies make them easy prey for many fish. Early life stages are consumed by bottom-dwelling fish like cod, flounder, sculpin, wolf fish, eels, dogfish, tench, and crabs. Estimates suggest that only about one percent of lobster larvae survive to reach the ocean floor.
As lobsters grow, predators shift to larger marine species. Adult lobsters are preyed upon by large fish, including cod, haddock, and monkfish, which can tear or break open their shells. Sharks, like nurse sharks, and rays can crush lobster shells.
Octopuses ambush lobsters and manipulate their tough exteriors. Marine mammals like seals and sea otters include lobsters in their diets, using their strong jaws to crush them. Opportunistic raccoons may prey on lobsters in shallow, intertidal zones.
Cannibalism can occur among lobsters, especially when they are held in crowded conditions or when one lobster is in a vulnerable state, such as during molting. Lobsters are particularly defenseless immediately after shedding their old shells, as their new shells take time to harden, leaving them exposed to both their own kind and other predators.
How Lobsters Avoid Predation
Lobsters possess physical and behavioral adaptations that aid survival in predator-rich environments. Their most apparent defense is their hard exoskeleton, a strong external shell composed of chitin and reinforced with calcium carbonate. This armor protects their soft internal organs from direct attacks. However, during molting, when lobsters shed their old shell to grow, they are temporarily soft and vulnerable, often seeking secluded spots to hide until their new shell hardens.
Their powerful claws serve as both offensive and defensive tools. The larger “crusher” claw breaks hard objects, while the smaller “pincer” claw is used for tearing. Lobsters use these appendages to deter attackers or defend their territory. If a limb is grasped, lobsters can intentionally shed it (autotomy) and later regenerate the lost appendage, allowing escape.
Behaviorally, lobsters are nocturnal, meaning they are most active at night, which helps them avoid many diurnal predators. During the day, they remain hidden in rocky crevices, under rocks, or within burrows they construct in sand or mud. When threatened, lobsters rapidly propel themselves backward using a powerful tail-flicking motion, known as the caridoid escape reaction. This swift backward thrust allows them to quickly evade danger and retreat into shelters.
Lobsters also employ camouflage as a defense mechanism. Their greenish-brown coloration helps them blend seamlessly with the rocky, seaweed-filled ocean floor, making them difficult for predators to spot. Juvenile lobsters can adjust the lightness of their coloration over several weeks to better match their immediate surroundings, enhancing their ability to remain concealed.