Environmental Protection Agency Narragansett Bay Commission University of Rhode Island Office of Marine Programs

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Feature Creatures

Holy Molting!
(Lobsters)

There are two types of lobsters in the world - the spiny lobster or Panulirus argus and the American lobster or Homarus americanus. The lobsters found in Narragansett Bay are Homarus americanus They live along the Eastern Seaboard from the Canadian Maritime Provinces to North Carolina. They prefer the cold waters along the New England coast to the warmer southern waters. According to The Uncommon Guide to Common Life of Narragansett by Frederick D. Massie: "Lobsters are the most valuable single-species fishery in the Rhode Island fishing economy."

The most distinguishing physical feature of the Homarus americanus are the two large front claws - the crusher and the ripper or tearing claws. These claws are used for killing and handling the lobsters' prey. The other spiny lobsters have smaller claws. The lobster shell is its skeleton. This is called an exoskeleton. In order for a lobster to grow it must molt which means it sheds its shell and grows a new one. Lobsters, along with shrimp, barnacles and crabs, are crustaceans. Crustaceans belong to the Arthropoda family, which includes spiders, insects, and horseshoe crabs.

Lobsters have eight walking legs, the first two have small claws to move the food from the crusher or ripper claw to the lobster's small mouth. The lobster uses antenna and hairy bristles along its body to hunt for food and sense dangers. They have eyes that stick out. They are active at night and swim backward by pumping their tails (when threatened). They can walk as far as a mile in one night while hunting for food. They have been known to eat their own species.

Adult females mate shortly after molting. They carry fertilized eggs on the underside of their tales for nine to twelve months. Females may carry between five to ten thousand eggs at a time. In the spring the female will move closer to the shore and release the eggs by lifting her tail and beating her swimmerets. Newly released from the egg casing, the baby lobsters are now larvae and plankton - they float to the top of the sea and float along with the currents. During this time they eat anything they can - including each other and are eaten by creatures larger than themselves. Of 10,000 eggs only 1/10 of one percent or maybe 10 eggs will survive the first four weeks of life.

The lobster will molt three times while they are plankton. By the fourth molt, it is heavy enough and its claws are developed enough for it to start its descent to the ocean bottom. After the fifth molt the lobster is at the bottom for good. It will spend the next few years hiding from fish and other lobsters. It will survive by eating whatever floats its way. It will molt about twenty five times in its first five years, after that it slows down to once or twice a year. An average 1 to 1.5 pound lobster is probably about six to eight years old.

Adult lobsters burrow in rock crevices or ledges. In a pinch they will bury themselves in mud for a day. Lobsters are cold blooded. They migrate nearer to shore in warm weather and to deep water for the fall and winter. Lobsters used to be much more plentiful in Narragansett Bay. Colonists and Native Americans could pick them up along the shore during low tides. They were used as fertilizer for the fields and as cheap food for prisoners and charity cases. It was considered cruel and unusual punishment to feed lobster to a prisoner or poor house inmate more than three times a week.

Lobsters are greenish brown on top and orange underneath. When cooked they turn red. Lobsterback was a derogatory term used during the American Revolutionary War towards English soldiers who wore red jackets.

Destruction of habitat, overfishing, and pollution threaten the future of lobsters. Codfish and humans are the lobsters' main enemies.

©2001 Debbie O'Hara



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