American Lobster (Homarus americanus)

• Populations of American lobster in the Gulf of Maine and Georges Bank are healthy and overfishing is not occurring. However, in Southern New England, lobster are overfished and overfishing is occurring.
• NOAA's National Marine Fisheries Service implements regulations for the American lobster fishery in offshore federal waters complementary to those implemented by the Atlantic States Marine Fisheries Commission in state waters.
• Lobster is low in saturated fat and is a very good source of protein and selenium. For more information, see Nutrition Facts. (USDA)
• American lobster is one of the most valuable fisheries in the Eastern United States, with landings of 75.2 million pounds valued at $350 million in 2007. Maine and Massachusetts accounted for over 90 percent of these landings.

Sustainability Status

Biomass: Gulf of Maine and Georges Bank abundance estimates are above their respective thresholds; Southern New England is not. The average abundance estimates of American lobster in the Gulf of Maine, Georges Bank, and Southern New England over the past 3 years have been 123 million lobsters, 9 million lobsters, and 19 to 25 million lobsters, respectively.
Overfishing: Yes (Southern New England); No (Gulf of Maine, Georges Bank)
Overfished: Yes (Southern New England); No (Gulf of Maine, Georges Bank)
Fishing and habitat: The principal fishing gear used to catch lobster is the trap. Lobster are also taken as bycatch in otter trawls. Lobster traps have very little impact on the habitat. Otter trawls may impact habitat, depending on where they are used.
Bycatch: A number of finfish (such as cod, tautog, scup, black sea bass, eels, and flounder) and invertebrates (such as rock, jonah, and red crabs and conch) can be found in lobster traps in both inshore and offshore fisheries. Ghost traps (lost gear that continues to fish) can also be a problem in the lobster fishery. Biodegradable escape panels or hinges are required on traps to prevent ghost fishing. NMFS implemented an October 2007 final rule requiring larger escape vents. The Northeast/Mid-Atlantic American lobster trap/pot fishery is a Category I fishery according to the Marine Mammal Protection Act's annual List of Fisheries. This means that annual mortality and serious injury of certain marine mammal stocks in this fishery is greater than or equal to 50 percent of the Potential Biological Removal level. NMFS is addressing this challenge through the Atlantic Large Whale Take Reduction Team, and implemented an October 2007 final rule to further protect large whales from American lobster gear.
Aquaculture: Research is currently underway to develop rearing techniques and to assess the economic feasibility of commercial aquaculture of American lobster.

Science and Management

In state waters (within 3 miles of shore), the American lobster fishery is currently managed under Amendment 3 and Addenda I through XII to the Atlantic States Marine Fisheries Commission's (ASMFC) Interstate Fishery Management Plan (FMP) for American Lobster. This FMP covers the U.S. portion of the Northwest Atlantic Ocean and adjacent inshore waters where lobsters are found. The coverage is divided into seven areas for management purposes. Amendment 3 set up a framework for area management that allows for industry participation through seven Lobster Conservation Management Teams, which are encouraged to develop area-specific management programs to address the fishery management needs of their respective management areas. In February 2007, Addendum X established new monitoring and reporting requirements for the lobster fishery.

NOAA's National Marine Fisheries Service (NMFS) has implemented complementary regulations for the American lobster fishery in offshore federal waters (3 to 200 miles from shore) under the Atlantic Coastal Fisheries Cooperative Management Act. The EEZ contains portions of six of the seven management areas; only Area 6 is totally within state waters. Federal management measures include minimum and maximum carapace length limits, protection of egg-bearing females, gear restrictions (trap size, gear marking requirements, escape vents, and ghost panels), trap limits, and several area-specific limited entry programs. Some regulations such as minimum and maximum carapace limits and trap limits vary among management areas.

Life History and Habitat

Life history, including information on the habitat, growth, feeding, and reproduction of a species, is important because it affects how a fishery is managed.

• Geographic range: American lobster is found in the Northwest Atlantic Ocean from Labrador to Cape Hatteras in coastal waters and out to depths of 2,300 feet. American lobster is most abundant inshore (out to a depth of about 131 feet) from Maine through New Jersey; it occurs offshore from Maine through North Carolina.
• Habitat: American lobster is a bottom-dwelling crustacean. Coastal lobsters are typically concentrated in rocky areas where shelter is readily available, although they are sometimes found in mud substrates suitable for burrowing. Offshore populations are most abundant along the continental shelf edge near submarine canyons.
• Life span: Lobsters are long-lived, but exact ages cannot be determined because lobster shed all hard parts when they molt, leaving no evidence of age. Scientists have estimated that the American lobster may live to be 100 years old, but it is more likely that the maximum age is 50 years.
• Food: Larvae and postlarvae are carnivorous and eat zooplankton (tiny floating animals) during their first year. Adult lobster are omnivorous, feeding on crabs, mollusks, polychaete worms, sea urchins, sea stars, fish, and macroalgae. Lobster are opportunistic feeders, so their diet varies regionally depending on the availability of prey species.
• Growth rate: Lobsters periodically molt (i.e., they shed their exoskeleton to grow). Older females tend to be smaller than males of the same age.
• Maximum size: The largest American lobster on record weighed 44 pounds.
• Reaches reproductive maturity: Lobsters molt about 20 to 25 times (over 5 to 8 years) between hatching and sexual maturity.
• Reproduction: Usually, lobsters mate after the females molt, or shed their hard, external skeleton. Males deposit sperm in the "soft" females. The female stores the sperm internally for a period of up to a year. Females can have 5,000 to 100,000 eggs, depending on their body size. The eggs are produced internally, and fertilized as they are extruded on the underside of the tail, where they are carried for a 9- to 11- month incubation period. The eggs hatch during late spring or early summer. The pelagic (free-swimming) larvae molt four times before attaining adult characteristics and settling to the bottom. They will molt over 20 times over a period of 5 to 8 years before they reach the minimum legal size.
• Spawning season: Variable; especially dependent on water temperature. Mating depends on when the female molts. Males and females mate within hours to a day after molting, but fertilization does not occur right away – sperm may be stored by the female for up to a year.
• Spawning grounds: No specific spawning grounds; egg-bearing females move inshore to hatch their eggs.
• Migrations: Near the coast, small lobsters do not move much, but larger ones may travel extensively. Offshore lobsters migrate during the spring anywhere from 50 miles to 190 miles.
• Predators: In general, predators of lobster include bottom or reef inhabiting species such as teleost fish, sharks, rays, skates, octopuses, and crabs. Larval and postlarval lobster are especially prone to predation. After settling to the mud bottom, they are eaten by mud crabs, cunner, and other bottom-feeding finfish species. When not in their burrows, juveniles are prey for sculpin, cunner, tautog, black sea bass, sea raven, Atlantic cod, wolffish, goosefish, tilefish, and several species of shark. Large, hard-shelled lobster may be immune to predation (except by humans).
• Commercial or recreational interest: Both; recreational fishing occurs in coastal waters
• Distinguishing characteristics: The American lobster is a bottom-dwelling, marine crustacean with a shrimp-like body and ten legs, two of which are enlarged and serve as crushing and gripping appendages.

Role in the Ecosystem

American lobsters compete for shelter with other bottom-dwelling species, such as crab, and various fish species that are common in rocky habitat. In muddy areas, lobsters dig large burrows for shelter. When they leave the shelter, the vacated burrows become habitat for other benthic species.

Additional Information

Human activities can have a significant impact on lobster and its environment. Deforestation, poor agricultural practices, urban development, quarrying, dredging, construction, or oil drilling can destroy habitat and adversely affect larval growth, development, and survival. Ocean dumping and disposal of dredged material can also impact lobster habitat and disrupt food resources. However, the dumping of uncontaminated material may enhance lobster habitat, once it is colonized with prey organisms.

Market name: Lobster
Vernacular name: None
European lobster (Homarus gammarus) is also marketed as Lobster.

Biomass

Biomass refers to the amount of American lobster in the ocean. Scientists cannot collect and weigh every single lobster to determine biomass, so they use models to estimate it instead. These biomass estimates can help determine if a stock is being fished too heavily or if it may be able to tolerate more fishing pressure. Managers can then make appropriate changes in the regulations of the fishery.

Three stocks - Gulf of Maine, Georges Bank, and Southern New England - support both inshore and offshore fisheries. The Gulf of Maine and Georges Bank lobster stocks have shown an increase in abundance over the past 10 to 15 years. The Southern New England stock increased in abundance from 1982 until 1997.

Landings

Landings refer to the amount of catch that is brought to land. Overall, the lobster fishery has expanded greatly from the late 1940s and early 1950s. Total landings were relatively constant around 31 million pounds through the late 1970s. More recently, lobster landings have risen from 62 million pounds in 1990 to 88 million pounds in 2005. Eighty percent of this catch is from state waters, and offshore landings have never comprised more than 20 percent of U.S. total landings.

In the Gulf of Maine, commercial landings have steadily increased since 1981. The majority of landings come from the nearshore trap fishery in Maine.

Georges Bank commercial landings were relatively stable, averaging over 3 million pounds (1,380 metric tons) annually, between 1981 and 2003. Since then, landings have risen to a high of over 5 million pounds (2,300 metric tons) in 2005.

Commercial landings in the Southern New England fishery increased from 5.7 million pounds (2,600 metric tons) in 1982 to 22.3 million pounds (10,100 metric tons) in 1997, but have since declined to 6.2 million pounds (2,800 metric tons) in 2005.

Note: Only domestic commercial landings are shown in the graph.

Biomass and Landings

Are landings and biomass related? Landings are dependent on biomass, management measures in the fishery, and fishing effort. In the Gulf of Maine, as biomass has increased, so has effort, including expansion into areas with previously low or no exploitation. There continues to be an excess of effort. Additionally, states report a substantial number of latent licenses that create the potential to increase that effort even further.

The Georges Bank lobster stock, although relatively stable, has shown a modest increase in abundance over the past 10 to15 years, and effort has simultaneously increased. The current efforts to limit and actually reduce effort should be continued.

As the Southern New England lobster stock increased in abundance from 1982 until 1997, effort increased to the point where abundance and landings began to decline. There continues to be an excess of effort.

Note: Biomass and landings are presented on different scales in the graph.

Data sources:
Biomass from Northeast Fisheries Science Center Status of Fishery Resources off the Northeastern U.S. – American Lobster

Landings from NMFS Annual Commercial Landings Statistics using "LOBSTER, AMERICAN" as Species and "ALL STATES" as State

Important Dates

1997 – Amendment 3 to the ASMFC American Lobster FMP is implemented
1999 – Commercial landings reach historic high of 89 million pounds
2007 – Addendum X established new monitoring and reporting requirements for the lobster fishery
2007 – Federal regulations for Area 3 off Southern New England amended to be consistent with recommendations from the ASFMC; new conservation measures include gauge size increases, an escape vent size increase (with implementation delayed until 2010), and trap reductions

Notes and Links

General Information:
Northeast Fisheries Science Center Status of Fishery Resources off the Northeastern U.S. – American Lobster

NEFSC Frequently Asked Questions

Fishery Management:
Atlantic States Marine Fisheries Commission - American Lobster Fishery Management

Stock Assessments:
ASMFC American Lobster Stock Assessment - January 2006

Northeast Fisheries Science Center Status of Fishery Resources off the Northeastern U.S. – American Lobster