American lobster

Homarus americanus

Order: Decapoda

Family: Nephropidae

Genus: Homarus

DESCRIPTION

The American lobster is a large, cold-water crustacean known for its hard exoskeleton and two oversized claws—one crusher and one pincher—used for defence and feeding. Its colour is typically greenish-brown to dark bluish-green in the wild, but rare colour morphs (blue, yellow, calico, albino) occasionally occur. Lobsters can regenerate lost claws and legs over time and are known for their complex life cycle and lengthy lifespan.

HEAD AND BODY LENGTH

Adult lobsters typically range from 20 to 60 centimetres (8 to 24 inches) in length, though larger specimens have been recorded.

TAIL LENGTH

The tail makes up about one-third of the body length and is muscular, used for swimming in quick backward bursts

WEIGHT

Commonly 0.5 to 4 kilograms (1 to 9 pounds), though rare individuals can exceed 10 kilograms (22 pounds)

Conservation Status: IUCN

Distribution

American lobsters live along the Atlantic coast of North America, especially abundant in Canadian waters (Nova Scotia, New Brunswick, Prince Edward Island) and the northeastern U.S.

Habitat

Found on rocky and muddy ocean bottoms from the shoreline to depths over 400 metres (1,300 feet). Juveniles hide among rocks or seaweed, while adults often dwell in burrows or crevices. Cold, well-oxygenated water is essential for survival.

Diet

Omnivorous scavengers and hunters. Their diet includes molluscs (clams, snails), other crustaceans, worms, sea urchins, algae, and occasionally fish. Lobsters use their crusher claw to break shells and the pincher to tear soft tissue.

Reproduction

Lobsters reach sexual maturity at around 5 to 9 years, depending on water temperature. Mating occurs shortly after the female moults. Females carry eggs for 9 to 12 months under their tails, fanning them with swimmerets until they hatch. A single female may carry up to 100,000 eggs, though only a few survive to adulthood.

Adaptation

Hard exoskeleton protects against predators and must be shed (moulted) for the lobster to grow
Claws serve as both weapons and tools
Highly sensitive antennae detect chemicals and vibrations in the water
Nocturnal behaviour and burrowing habits help avoid predators
Regeneration of lost limbs improves survival

Threats to Survival

Climate change: Rising ocean temperatures may shift lobster distribution northward
Ocean acidification: May affect shell development in juveniles
Pollution: Especially in inshore nurseries
Overfishing: Well-managed but still a concern in some regions without proper regulation
Diseases: Such as shell disease in warmer waters