Lobsters are marine crustaceans with a segmented body and exoskeleton. They possess five pairs of legs, some modified into pincers, compound eyes on stalks, and a flipper-like tail for swimming. True lobsters (Homaridae) have large claws on their first three pairs of legs and are found in most seas except polar regions and the deep sea. The American lobster ( Homarus americanus ) is a valuable species, typically caught in lobster pots. Females can lay thousands of eggs that hatch months later. Lobsters can live for many years and are preyed upon by various animals, including humans.

What kind of animal is a lobster?

Lobsters are marine crustaceans that belong to the phylum Arthropoda and order Decapoda. They are bottom-dwelling creatures found in oceans worldwide and are generally nocturnal. Lobsters have segmented bodies covered by a rigid exoskeleton and five pairs of legs, some of which are modified into pincers. They possess compound eyes on movable stalks, two pairs of antennae, and swimmerets on their abdomen. Lobsters use their muscular tail for swimming, propelling themselves backward by flexing their tail and abdomen. True lobsters have claws on their first three pairs of legs, with large claws on the first pair and a distinct snout. They scavenge for dead animals and consume live fish, mollusks, and seaweed. Some lobster species are commercially important as food for humans.

Where do lobsters live?

Lobsters are marine crustaceans found on the sea bottom, with different families inhabiting various regions. True lobsters (Homaridae) are located in all but polar seas and the greater depths. The American lobster ( Homarus americanus ) is found in waters from Labrador to North Carolina, while the European lobster ( H. gammarus ) inhabits the rocky bottoms of the European Atlantic coast and the Mediterranean Sea. Spiny lobsters (Palinuridae) are mainly in tropical waters, but Palinurus elephas can be found from Great Britain to the Mediterranean Sea. Slipper lobsters (Scyllaridae) are mainly tropical, while deep-sea lobsters (Polychelidae) reside in the deep sea.

How do lobsters protect themselves in the wild?

Lobsters have several adaptations to protect themselves in the wild:

What do lobsters eat, and how do they find their food?

Lobsters are marine crustaceans that dwell on the sea bottom and are mostly active at night. They are scavengers that feed on dead animals. They also consume live fish, small mollusks, other bottom-dwelling invertebrates, and seaweed. Lobsters have special water-displacement receptors that are reminiscent of the lateral-line organs in vertebrates. These receptors allow them to orient themselves in rivers and tidal currents. Many predatory crustaceans also respond chemically, moving against the current until they reach their prey.

How do lobsters grow and change throughout their lives?

Lobsters, like other crustaceans , grow and change through a process called molting because their rigid exoskeleton prevents continuous growth. Molting is a series of stages that includes premolt, shedding the old exoskeleton, postmolt (during which the new cuticle hardens), and intermolt. During premolt, calcium is absorbed from the old exoskeleton, and a new exoskeleton develops. To shed the old exoskeleton, it splits, and the lobster withdraws its body. After shedding, the lobster takes in water to expand, and the new cuticle hardens. The time between molts varies. Some crustaceans, like lobsters and crabs, continue to molt throughout their lives. This process is controlled by hormones.

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Introduction References & Edit History Related Topics

Images & Videos

Why do lobsters change color when cooked?

A man in rubber gloves and yellow apron stands on a lobster boat in Maine, hauling a wooden lobster trap from the sea near the boat's edge.

lobster fishing, Cape Breton, Nova Scotia, Canada

Observe social interactions of bottlenose dolphins at Scandola Nature Reserve on the coast of Corsica, also home to crabs and lobsters and other marine life

At a Glance

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Quick Facts

Related Topics:: Do lobsters mate for life?; scampi; slipper lobster; spiny lobster; Homaridae

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lobster

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Top Questions

What is a lobster?
Lobsters are marine crustaceans with a segmented body and exoskeleton. They possess five pairs of legs, some modified into pincers, compound eyes on stalks, and a flipper-like tail for swimming. True lobsters (Homaridae) have large claws on their first three pairs of legs and are found in most seas except polar regions and the deep sea. The American lobster (Homarus americanus) is a valuable species, typically caught in lobster pots. Females can lay thousands of eggs that hatch months later. Lobsters can live for many years and are preyed upon by various animals, including humans.
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1. lobster
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What kind of animal is a lobster?
Lobsters are marine crustaceans that belong to the phylum Arthropoda and order Decapoda. They are bottom-dwelling creatures found in oceans worldwide and are generally nocturnal.

Lobsters have segmented bodies covered by a rigid exoskeleton and five pairs of legs, some of which are modified into pincers. They possess compound eyes on movable stalks, two pairs of antennae, and swimmerets on their abdomen. Lobsters use their muscular tail for swimming, propelling themselves backward by flexing their tail and abdomen.

True lobsters have claws on their first three pairs of legs, with large claws on the first pair and a distinct snout. They scavenge for dead animals and consume live fish, mollusks, and seaweed. Some lobster species are commercially important as food for humans.
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2. lobster
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Where do lobsters live?
Lobsters are marine crustaceans found on the sea bottom, with different families inhabiting various regions. True lobsters (Homaridae) are located in all but polar seas and the greater depths. The American lobster (Homarus americanus) is found in waters from Labrador to North Carolina, while the European lobster (H. gammarus) inhabits the rocky bottoms of the European Atlantic coast and the Mediterranean Sea. Spiny lobsters (Palinuridae) are mainly in tropical waters, but Palinurus elephas can be found from Great Britain to the Mediterranean Sea. Slipper lobsters (Scyllaridae) are mainly tropical, while deep-sea lobsters (Polychelidae) reside in the deep sea.
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How do lobsters protect themselves in the wild?
Lobsters have several adaptations to protect themselves in the wild:
- Exoskeleton: Lobsters possess a rigid exoskeleton that protects their soft tissues and provides attachment sites for muscles.
- Camouflage: Lobsters use coloration to blend in with their surroundings, providing concealment from predators. Some species can even change color to match their environment.
- Claws: True lobsters have claws on their first three pairs of legs, with very large claws on the first pair, which can be used for defense.
- Molting: While the new exoskeleton is soft, the rapid intake of water immediately after ecdysis helps the crustacean swell, and makes it more difficult for predators to harm them.
- Nocturnal Behavior: Most lobsters are nocturnal, reducing their encounters with predators that hunt during the day.
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What do lobsters eat, and how do they find their food?
Lobsters are marine crustaceans that dwell on the sea bottom and are mostly active at night. They are scavengers that feed on dead animals. They also consume live fish, small mollusks, other bottom-dwelling invertebrates, and seaweed.

Lobsters have special water-displacement receptors that are reminiscent of the lateral-line organs in vertebrates. These receptors allow them to orient themselves in rivers and tidal currents. Many predatory crustaceans also respond chemically, moving against the current until they reach their prey.
5 Britannica Sources
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
How do lobsters grow and change throughout their lives?
Lobsters, like other crustaceans, grow and change through a process called molting because their rigid exoskeleton prevents continuous growth. Molting is a series of stages that includes premolt, shedding the old exoskeleton, postmolt (during which the new cuticle hardens), and intermolt.

During premolt, calcium is absorbed from the old exoskeleton, and a new exoskeleton develops. To shed the old exoskeleton, it splits, and the lobster withdraws its body. After shedding, the lobster takes in water to expand, and the new cuticle hardens. The time between molts varies. Some crustaceans, like lobsters and crabs, continue to molt throughout their lives. This process is controlled by hormones.
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Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

lobster, any of numerous marine crustaceans (phylum Arthropoda, order Decapoda) constituting the families Homaridae (or Nephropsidae), true lobsters; Palinuridae, spiny lobsters, or sea crayfish; Scyllaridae, slipper, Spanish, or shovel lobsters; and Polychelidae, deep-sea lobsters. All are marine and benthic (bottom-dwelling), and most are nocturnal. Lobsters scavenge for dead animals but also eat live fish, small mollusks and other bottom-dwelling invertebrates, and seaweed. Some species, especially of true and spiny lobsters, are commercially important to humans as food.

The lobster has a rigid, segmented body covering (exoskeleton) and five pairs of legs, one or more pairs of which are often modified into pincers (chelae) with the chela on one side usually larger than that on the other. Lobsters have compound eyes on movable stalks, two pairs of long antennae, and several pairs of swimming legs (swimmerets) on the elongated abdomen. A flipperlike muscular tail is used for swimming; flexure of the tail and abdomen propel the animal backward.

The true lobsters (Homaridae) have claws (chelae) on the first three pairs of legs, with very large claws on the first pair. They have a distinct rostrum, or snout, on the carapace, which covers the head and thorax, or midsection. The American lobster (Homarus americanus) and the Norway lobster, also known as Dublin Bay prawn and scampi (Nephrops norvegicus), are the most valuable species and are often marketed alive; people eat the heavily muscled abdomen and claws. True lobsters are found in all but polar seas and the greater depths. H. gammarus, the European lobster, a dark greenish animal, occurs on rocky bottoms of the European Atlantic coast and the Mediterranean Sea. H. capensis, of the waters around South Africa, grows to 10 or 13 cm (4 to 5 inches) and is of little commercial value.

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H. americanus, found in waters from Labrador to North Carolina, sometimes dwells in shallow water but is more abundant in deeper water down to 366 metres (1,200 feet). Lobsters caught in shallow water weigh about 0.45 kg (about one pound) and are about 25 cm (about 10 inches) long. They are caught usually in lobster pots—cages baited with dead fish. In deeper water, they weigh about 2.5 kg (about 5.5 pounds) and are often caught by trawling. Exceptionally large specimens may weigh 20 kg (40 pounds). The American lobster is often marketed alive. It is commonly blackish green or brownish green above and yellow orange, red, or blue underneath. The red colour of cooked lobsters is caused by immersion in hot water.

Females are ready to lay eggs when about five years old. Males transfer sperm to females in summer, but eggs are not fertilized until spring. A female lays 3,000 or more eggs, which remain attached to her swimmerets until they hatch several months later. Unlike adults, the larvae, about 1 cm (0.4 inch) long, swim freely for about 12 days and then descend to the bottom, where they remain. The life span of some lobsters in the wild may be as long as 50 years, with the oldest individuals living 100 years or more. Young lobsters are preyed upon especially by dogfish, skates, and cod. Humans are the principal predators of adult lobsters.

Unlike true lobsters, spiny lobsters (Palinuridae), so called because of their very spiny bodies, do not have large claws. People eat the abdomen, which is marketed as lobster tail. The antennae are long. Most species live in tropical waters; Palinurus elephas, however, is found from Great Britain to the Mediterranean Sea. Two palinurid species are commercially important in the Americas: Palinurus interruptus, the California spiny lobster of the Pacific coast, and P. argus, the West Indian spiny lobster, from Bermuda to Brazil. P. interruptus attains lengths of about 40 cm (16 inches); P. argus about 45 cm (18 inches). Jasus lalandei, the commercially important South African rock lobster, occurs in waters around South Africa.

The mainly tropical slipper lobsters (Scyllaridae) are rather flat and clawless, with antennae flattened into broad plates. Most species are short and small and of little economic importance. Deep-sea lobsters (Polychelidae) are soft, weak animals with claws; some are blind. None is commercially important.

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