American lobster
Encyclopedia
The American lobster, Homarus americanus, is a species
of lobster
found on the Atlantic coast
of North America
, chiefly from Labrador
to New Jersey
. Within North America, it is also known as the northern lobster or Maine lobster. It can reach a body length of 64 cm (25.2 in), and a mass
of over 20 kilograms (44.1 lb), making it the heaviest crustacean
in the world. Its closest relative is the European lobster Homarus gammarus, which can be distinguished by its coloration and the lack of spines on the underside of the rostrum
. American lobsters are usually bluish green to brown with red spines, but a number of color variations have been observed.
coast of North America
, from Labrador
in the north to Cape Hatteras
, North Carolina
in the south. South of New Jersey
, the species is uncommon, and landings in Delaware
, Maryland
, Virginia
and North Carolina usually make up less than 0.1% of all landings. A fossil
claw
assigned to Homarus americanus was found at Nantucket, dating from the Pleistocene
.
in the world; an average adult is about 9 in (228.6 mm) long and weighs 1.5 to 2 lb (680.4 to 907.2 g). The longest American lobsters have a body (excluding claws) 64 cm (25.2 in) long. According to Guinness World Records
, the heaviest crustacean
ever recorded was an American lobster caught off Nova Scotia, Canada, weighing 44.4 lb (20.1 kg) and having a total length of 3.51 ft (1.07 m).
The closest relative of H. americanus is the European lobster, Homarus gammarus. The two species are very similar, and can be crossed artificially, although hybrids are unlikely to occur in the wild since their ranges do not overlap. The two species can be distinguished by a number of characteristics:
measure about 2 in (5.1 cm) long and split into Y-shaped structures with pointed tips. Each tip exhibits a dense zone of hair tufts staggered in a zigzag arrangement. These hairs are covered with multiple nerve cells that can detect odors. Larger, thicker hairs found along the edges control the flow of water, containing odor molecules, to the inner sensory hairs. The shorter antennules provide a further sense of smell. By having a pair of olfactory organs, a lobster can locate the direction a smell comes from, much the same way humans can hear the direction a sound comes from. In addition to sensing smells, the antennules can judge water speed to improve direction finding.
Lobsters have two urinary bladder
s, located on either side of the head. Lobsters use scents to communicate what and where they are, and those scents are in the urine
. They project long plumes of urine 1 metre in front of them, and do so when they detect a rival or a potential mate in the area.
s. The larger one is the "crusher", and has rounded nodules used for crushing prey; the other is the "cutter", which has sharp inner edges, and is used for holding or tearing the prey.
An estimated one in 2–5 million lobsters is blue. A genetic mutation causes a blue lobster to produce an excessive amount of a particular protein. The protein and a red carotenoid
molecule known as astaxanthin
combine to form a blue complex known as crustacyanin, giving the lobster its blue color. In 2009 a blue lobster was caught in New Hampshire by a fisherman who thought he had caught a shiny blue beer can. In 2011, two blue lobsters were caught in Canada, one off of Prince Edward Island
, and another was caught in the Esgenoôpetitj First Nation territory in New Brunswick
.
Yellow lobsters are the result of a rare genetic mutation and the odds of finding one are estimated to be 1 in 30 million. Reports of yellow lobsters include one off Whaleback Island (at the mouth of the Kennebec River
), Maine
, on August 1, 2006, off Prince Edward Island
, Canada, on June 11, 2009, one discovered in Wainani Kai Seafoods in Kalihi, Hawaii
in a shipment from Nova Scotia
on April 30, 2010, in Narragansett Bay
off Rhode Island
on July 31, 2010.
In July 2010, an albino lobster was reportedly caught in Gloucester
. An estimated only one in 100 million lobsters is albino
— lacking in colored pigments.
On August 28, 2010, a calico lobster with a mottled orange and black shell was reported to have been caught in Maine. Diane Cowan, a lobster scientist and founder of the Lobster Conservancy in Friendship
stated only albino lobsters are rarer, and orange lobsters such as these are a 1 in 30 million catch.
Several lobsters have been caught with different colorings on their left and right halves. For instance, on July 13, 2006, a Maine fisherman caught a brown and orange lobster, and submitted it to the local oceanarium, which had only seen three lobsters of this kind in 35 years. The chance of finding one is estimated at 1 in 50 million. All split-colored lobsters observed by Bob Bayer of the Lobster Institute in Maine have been hermaphroditic
.
Red lobsters are the usual result of a lobster being cooked. According to the Gulf of Maine Institute, however, there is a 1 in 10 million chance of catching one alive with that color.
of H. americanus is well understood. Mating
only takes place shortly after the female has molted
, and her exoskeleton
is still soft. The female releases a pheromone
which causes the males to become less aggressive and to begin courtship
, which involves a courtship dance with claws closed. Eventually, the male inserts spermatophore
s (sperm
packets) into the female's seminal receptacle using his first pleopods; the female may store the sperm for up to 15 months.
The female releases eggs
through her oviducts, and they pass the seminal receptacle and are fertilized
by the stored sperm. They are then attached to the female's pleopods (swimmerets) using an adhesive, where they are cared for until they are ready to hatch. The female cleans the eggs regularly, and fans them with water to keep them oxygenated. The large telolecithal
eggs may resemble the segments of a raspberry
, and a female carrying eggs is said to be "in berry". Since this period lasts 10–11 months, berried females can be found at any time of year. In the waters off New England
, the eggs are typically laid in July or August, and hatch the following May or June. The developing embryo
passes through several molts within the egg, before hatching as a metanauplius
larva. When the eggs hatch, the female releases them by waving her tail in the water, setting batches of larvae free.
The metanauplius of H. americanus is 1/3 in long, transparent, with large eyes and a long spine projecting from its head. It quickly molts, and the next three stages are similar, but larger. These molts take 10–20 days, during which the plankton
ic larvae are vulnerable to predation; only 1 in 1,000 is thought to survive to the juvenile stage. To reach the fourth stage – the post-larva – the larva undergoes metamorphosis
, and subsequently shows a much greater resemblance to the adult lobster, is around 1/2 in long, and swims with its pleopods.
After the next molt, the lobster sinks to the ocean floor, and adopts a benthic
lifestyle. It molts more and more infrequently, from an initial rate of ten times per year to once every few years. After one year, it is around 1 inch long, and after six years, it may weigh 1 pound (0.45359237 kg). By the time it reaches the minimum landing size
, an individual may have molted 25–27 times, and thereafter each molt may signal a 40%–50% increase in weight, and a 14% increase in carapace
length.
American lobsters are a popular food, with an image of refinement. They are commonly boiled or steamed. Hardshells (lobsters that are several months past their last molt) can survive out of water for up to two days if kept refrigerated. Softshells (lobsters that have only recently molted) do not survive more than a few hours out of water. Lobsters are usually cooked alive, which some people consider inhumane.
One common way of serving lobster 'tail' (actually the abdomen
) is with beef
, known as surf and turf
. Lobsters have a greenish or brownish organ called the tomalley
that performs the functions of the liver
and pancreas
in a human, i.e., it filters out toxin
s from the body. Some diners consider it a delicacy, but others avoid it because they consider it a toxin
source or dislike eating innards.
A set of nutcrackers and a long, thin tool for pulling meat from inaccessible areas are suggested as basics, although more experienced diners can eat the animal with their bare hands or a simple tool (a fork, knife or rock). Eating a lobster can get messy, and most restaurants offer a lobster bib. Meat is generally contained in the larger claws and tails, and stays warm quite a while after being served. There is some meat in the legs and in the arms that connect the large claws to the body. There is also some small amount of meat just below the carapace around the thorax and in the smaller legs.
Most lobsters come from the northeastern coast of North America, with the Atlantic Provinces of Canada and the U.S. state
of Maine
being the largest producers. They are caught primarily using lobster trap
s, although lobsters are also harvested as bycatch
by bottom trawlers
, fishermen using gillnet
s, and by scuba divers in some areas. Maine completely prohibits scuba divers from catching lobsters (violations could result in up to a $1000 fine). Massachusetts offers scuba divers lobster licenses for a fee, and they are only available to state residents. Rhode Island also requires divers to acquire a permit.
Lobster traps are rectangular cages made of vinyl-coated galvanized steel mesh or wood, with woven mesh entrances. These are baited and lowered to the sea floor. They allow a lobster to enter, but make it difficult for the larger specimens to turn around and exit. This allows the creatures to be captured alive. The traps, sometimes referred to as "pots", have a buoy
floating on the surface, and lobstermen check their traps between one and seven days after setting them. The inefficiency of the trapping system has inadvertently prevented the lobster population from being overfished. Lobsters can easily escape the trap, and will defend the trap against other lobsters because it is a source of food. An estimated 10% of lobsters that encounter a trap enter, and only 6% will actually be caught.
In the United States, the lobster industry is regulated
. Every lobsterman is required to use a lobster gauge to measure the distance from the lobster's eye socket to the end of its carapace: if the lobster is less than 3.25 inches (8.3 cm) long, it is too young to be sold and must be released back to the sea. There is also a legal maximum size of 5 in (12.7 cm) in Maine, meant to ensure the survival of a healthy breeding stock of adult males, but in parts of some states, such as Massachusetts, there is none. Also, traps must contain an escape hole or "vent", which allows juvenile lobsters and bycatch species to escape. The law in Maine and other states dictates a second large escape hole or "ghost panel" must be installed. This hole is held shut through use of biodegradable clips made of ferrous metal. Should the trap become lost, the trap eventually opens, allowing the catch to escape.
To protect known breeding females, lobsters caught carrying eggs are to be notched on a tail flipper (second from the right, if the lobster is right-side up and the tail is fully extended). Following this, the female cannot be kept or sold, and is commonly referred to as a "punch-tail" or as "v-notched". This notch remains for two molts of the lobster exoskeleton, providing harvest protection and continued breeding availability for up to five years.
In the late 1990s and early 21st century, lobster fishing was the cause of troubles between Acadians and Mi'kmaq First Nations in the Canadian Maritimes. The Acadian economy (and identity) relied substantially on fisheries, especially lobster. In 1998, the Supreme Court of Canada
ruled in favor of the First Nations and granted them unlimited rights to natural resources, based on an 18th-century treaty. The federal government tried to take licenses and quotas from the traditional fishermen, whose fishing quota had already dropped dramatically in the years before, and give them to the natives. Burnt Church, a reserve
between Miramichi
and the Acadian town of Neguac, was the hub of these troubles. The tension increased and decreased with each fishing season, reaching its climax came in April 2003, when a riot broke in the port of Shippagan, where three native-owned fishing ships and a fish processing plant were burnt down. Since then, efforts have been made to bring Acadians and natives closer together, and the tension has slowly abated.
, small crustacean
s, and mollusks
.
or red-tail is an extremely virulent infectious disease of lobsters caused by the bacterium Aerococcus viridans. It only requires a few bacterial cells to cause death of otherwise healthy lobsters. The "red tail" common name refers to a dark orange discoloration of the ventral abdomen of affected lobsters. This is, in fact, the haemolymph or blood seen through the thin ventral arthrodial membranes. The red discoloration comes from astaxanthin
, a carotenoid
pigment exported to the blood during times of stress. The same sign is also seen in other diseases of lobsters and appears to be a nonspecific stress response, possibly relating to the antioxidant and immunostimulatory properties of the astaxanthin molecule.
Paramoebiasis
is an infectious disease of lobsters caused by infection with the sarcomastigophoran (ameba) Neoparamoeba
pemaquidensis. This organism also causes amebic gill disease
in farmed Atlantic salmon
, Salmo salar. Infection occurs throughout the tissues, causing granuloma
-like lesions, especially within the ventral nerve cord, the interstices of the hepatopancreas
and the antennal gland. Paramoebiasis is strongly suspected to play a prominent role in the rapid die-off of American lobsters in Long Island Sound
that occurred in the summer of 1999.
Systemic infections by the bacterium Vibrio fluvialis (or similar organisms) are reported to cause "limp lobster disease", wherein lobsters become lethargic and die.
Excretory calcinosis in American lobsters in Long Island Sound was described from an epizootic in 2002. The disease causes mineralized calculi
to form in the antennal glands and gills. These cause a loss of surface area around the gills, and the lobster eventually asphyxiates. Several reasons have been proposed for the cause of a recent outbreak of the disease. The most generally attributed factor is an increased duration of warmer temperatures in the bottom of the Long Island Sound.
by Thomas Say
in 1817, with a type locality of "Long-branch
, part of the coast of New Jersey
". The name Say chose, however – "Astacus marinus" – was invalid as a junior homonym of Astacus marinus Fabricius, 1775, which is in turn a junior synonym
of Homarus gammarus. The American lobster was given its current scientific name of Homarus americanus by Henri Milne-Edwards
in his 1837 work ("Natural History of the Crustacea"). The common name
preferred by the Food and Agriculture Organization
is "American lobster", but the species is also known locally as the "northern lobster", "Maine lobster" or simply "lobster".
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of lobster
Lobster
Clawed lobsters comprise a family of large marine crustaceans. Highly prized as seafood, lobsters are economically important, and are often one of the most profitable commodities in coastal areas they populate.Though several groups of crustaceans are known as lobsters, the clawed lobsters are most...
found on the Atlantic coast
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
of North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
, chiefly from Labrador
Labrador
Labrador is the distinct, northerly region of the Canadian province of Newfoundland and Labrador. It comprises the mainland portion of the province, separated from the island of Newfoundland by the Strait of Belle Isle...
to New Jersey
New Jersey
New Jersey is a state in the Northeastern and Middle Atlantic regions of the United States. , its population was 8,791,894. It is bordered on the north and east by the state of New York, on the southeast and south by the Atlantic Ocean, on the west by Pennsylvania and on the southwest by Delaware...
. Within North America, it is also known as the northern lobster or Maine lobster. It can reach a body length of 64 cm (25.2 in), and a mass
Mass
Mass can be defined as a quantitive measure of the resistance an object has to change in its velocity.In physics, mass commonly refers to any of the following three properties of matter, which have been shown experimentally to be equivalent:...
of over 20 kilograms (44.1 lb), making it the heaviest crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
in the world. Its closest relative is the European lobster Homarus gammarus, which can be distinguished by its coloration and the lack of spines on the underside of the rostrum
Rostrum (anatomy)
The term rostrum is used for a number of unrelated structures in different groups of animals:*In crustaceans, the rostrum is the forward extension of the carapace in front of the eyes....
. American lobsters are usually bluish green to brown with red spines, but a number of color variations have been observed.
Distribution
Homarus americanus is distributed along the AtlanticAtlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
coast of North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
, from Labrador
Labrador
Labrador is the distinct, northerly region of the Canadian province of Newfoundland and Labrador. It comprises the mainland portion of the province, separated from the island of Newfoundland by the Strait of Belle Isle...
in the north to Cape Hatteras
Cape Hatteras
Cape Hatteras is a cape on the coast of North Carolina. It is the point that protrudes the farthest to the southeast along the northeast-to-southwest line of the Atlantic coast of North America...
, North Carolina
North Carolina
North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte...
in the south. South of New Jersey
New Jersey
New Jersey is a state in the Northeastern and Middle Atlantic regions of the United States. , its population was 8,791,894. It is bordered on the north and east by the state of New York, on the southeast and south by the Atlantic Ocean, on the west by Pennsylvania and on the southwest by Delaware...
, the species is uncommon, and landings in Delaware
Delaware
Delaware is a U.S. state located on the Atlantic Coast in the Mid-Atlantic region of the United States. It is bordered to the south and west by Maryland, and to the north by Pennsylvania...
, Maryland
Maryland
Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...
, Virginia
Virginia
The Commonwealth of Virginia , is a U.S. state on the Atlantic Coast of the Southern United States. Virginia is nicknamed the "Old Dominion" and sometimes the "Mother of Presidents" after the eight U.S. presidents born there...
and North Carolina usually make up less than 0.1% of all landings. A fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
claw
Claw
A claw is a curved, pointed appendage, found at the end of a toe or finger in most mammals, birds, and some reptiles. However, the word "claw" is also often used in reference to an invertebrate. Somewhat similar fine hooked structures are found in arthropods such as beetles and spiders, at the end...
assigned to Homarus americanus was found at Nantucket, dating from the Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....
.
Description
Homarus americanus commonly reaches 8–24 in (20.3–61 ) long and weighs 1–9 lb (0.45359237–4.1 ) in weight, but has been known to reach lengths over 3 ft (0.9144 m) and weigh as much as 44 lb (20 kg) or more, making this the heaviest marine crustacean in the world. Together with Sagmariasus verreauxi, it is also the longest decapod crustaceanDecapoda
The decapods or Decapoda are an order of crustaceans within the class Malacostraca, including many familiar groups, such as crayfish, crabs, lobsters, prawns and shrimp. Most decapods are scavengers. It is estimated that the order contains nearly 15,000 species in around 2,700 genera, with...
in the world; an average adult is about 9 in (228.6 mm) long and weighs 1.5 to 2 lb (680.4 to 907.2 g). The longest American lobsters have a body (excluding claws) 64 cm (25.2 in) long. According to Guinness World Records
Guinness World Records
Guinness World Records, known until 2000 as The Guinness Book of Records , is a reference book published annually, containing a collection of world records, both human achievements and the extremes of the natural world...
, the heaviest crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
ever recorded was an American lobster caught off Nova Scotia, Canada, weighing 44.4 lb (20.1 kg) and having a total length of 3.51 ft (1.07 m).
The closest relative of H. americanus is the European lobster, Homarus gammarus. The two species are very similar, and can be crossed artificially, although hybrids are unlikely to occur in the wild since their ranges do not overlap. The two species can be distinguished by a number of characteristics:
- The rostrumRostrum (anatomy)The term rostrum is used for a number of unrelated structures in different groups of animals:*In crustaceans, the rostrum is the forward extension of the carapace in front of the eyes....
of H. americanus bears one or more spines on the underside, which are lacking in H. gammarus. - The spines on the claws of H. americanus are red or red-tipped, while those of H. gammarus are white or white-tipped.
- The underside of the claw of H. americanus is orange or red, while that of H. gammarus is creamy white or very pale red.
Head
The antennaeAntenna (biology)
Antennae in biology have historically been paired appendages used for sensing in arthropods. More recently, the term has also been applied to cilium structures present in most cell types of eukaryotes....
measure about 2 in (5.1 cm) long and split into Y-shaped structures with pointed tips. Each tip exhibits a dense zone of hair tufts staggered in a zigzag arrangement. These hairs are covered with multiple nerve cells that can detect odors. Larger, thicker hairs found along the edges control the flow of water, containing odor molecules, to the inner sensory hairs. The shorter antennules provide a further sense of smell. By having a pair of olfactory organs, a lobster can locate the direction a smell comes from, much the same way humans can hear the direction a sound comes from. In addition to sensing smells, the antennules can judge water speed to improve direction finding.
Lobsters have two urinary bladder
Urinary bladder
The urinary bladder is the organ that collects urine excreted by the kidneys before disposal by urination. A hollow muscular, and distensible organ, the bladder sits on the pelvic floor...
s, located on either side of the head. Lobsters use scents to communicate what and where they are, and those scents are in the urine
Urine
Urine is a typically sterile liquid by-product of the body that is secreted by the kidneys through a process called urination and excreted through the urethra. Cellular metabolism generates numerous by-products, many rich in nitrogen, that require elimination from the bloodstream...
. They project long plumes of urine 1 metre in front of them, and do so when they detect a rival or a potential mate in the area.
Thorax
The first pair of pereiopods (legs) is armed with a large, asymmetrical pair of clawClaw
A claw is a curved, pointed appendage, found at the end of a toe or finger in most mammals, birds, and some reptiles. However, the word "claw" is also often used in reference to an invertebrate. Somewhat similar fine hooked structures are found in arthropods such as beetles and spiders, at the end...
s. The larger one is the "crusher", and has rounded nodules used for crushing prey; the other is the "cutter", which has sharp inner edges, and is used for holding or tearing the prey.
Coloration
The normal coloration of Homarus americanus is "dark bluish green to greenish brown", redder on the body and claws, and greener on the legs. This coloration is produced by mixing yellow, blue, and red pigments.An estimated one in 2–5 million lobsters is blue. A genetic mutation causes a blue lobster to produce an excessive amount of a particular protein. The protein and a red carotenoid
Carotenoid
Carotenoids are tetraterpenoid organic pigments that are naturally occurring in the chloroplasts and chromoplasts of plants and some other photosynthetic organisms like algae, some bacteria, and some types of fungus. Carotenoids can be synthesized fats and other basic organic metabolic building...
molecule known as astaxanthin
Astaxanthin
Astaxanthin is a carotenoid. It belongs to a larger class of phytochemicals known as terpenes. It is classified as a xanthophyll, which means "yellow leaves". Like many carotenoids, it is a colorful, lipid-soluble pigment. Astaxanthin is found in microalgae, yeast, salmon, trout, krill, shrimp,...
combine to form a blue complex known as crustacyanin, giving the lobster its blue color. In 2009 a blue lobster was caught in New Hampshire by a fisherman who thought he had caught a shiny blue beer can. In 2011, two blue lobsters were caught in Canada, one off of Prince Edward Island
Prince Edward Island
Prince Edward Island is a Canadian province consisting of an island of the same name, as well as other islands. The maritime province is the smallest in the nation in both land area and population...
, and another was caught in the Esgenoôpetitj First Nation territory in New Brunswick
New Brunswick
New Brunswick is one of Canada's three Maritime provinces and is the only province in the federation that is constitutionally bilingual . The provincial capital is Fredericton and Saint John is the most populous city. Greater Moncton is the largest Census Metropolitan Area...
.
Yellow lobsters are the result of a rare genetic mutation and the odds of finding one are estimated to be 1 in 30 million. Reports of yellow lobsters include one off Whaleback Island (at the mouth of the Kennebec River
Kennebec River
The Kennebec River is a river that is entirely within the U.S. state of Maine. It rises in Moosehead Lake in west-central Maine. The East and West Outlets join at Indian Pond and the river then flows southward...
), Maine
Maine
Maine is a state in the New England region of the northeastern United States, bordered by the Atlantic Ocean to the east and south, New Hampshire to the west, and the Canadian provinces of Quebec to the northwest and New Brunswick to the northeast. Maine is both the northernmost and easternmost...
, on August 1, 2006, off Prince Edward Island
Prince Edward Island
Prince Edward Island is a Canadian province consisting of an island of the same name, as well as other islands. The maritime province is the smallest in the nation in both land area and population...
, Canada, on June 11, 2009, one discovered in Wainani Kai Seafoods in Kalihi, Hawaii
Hawaii
Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...
in a shipment from Nova Scotia
Nova Scotia
Nova Scotia is one of Canada's three Maritime provinces and is the most populous province in Atlantic Canada. The name of the province is Latin for "New Scotland," but "Nova Scotia" is the recognized, English-language name of the province. The provincial capital is Halifax. Nova Scotia is the...
on April 30, 2010, in Narragansett Bay
Narragansett Bay
Narragansett Bay is a bay and estuary on the north side of Rhode Island Sound. Covering 147 mi2 , the Bay forms New England's largest estuary, which functions as an expansive natural harbor, and includes a small archipelago...
off Rhode Island
Rhode Island
The state of Rhode Island and Providence Plantations, more commonly referred to as Rhode Island , is a state in the New England region of the United States. It is the smallest U.S. state by area...
on July 31, 2010.
In July 2010, an albino lobster was reportedly caught in Gloucester
Gloucester, Massachusetts
Gloucester is a city on Cape Ann in Essex County, Massachusetts, in the United States. It is part of Massachusetts' North Shore. The population was 28,789 at the 2010 U.S. Census...
. An estimated only one in 100 million lobsters is albino
Albinism
Albinism is a congenital disorder characterized by the complete or partial absence of pigment in the skin, hair and eyes due to absence or defect of an enzyme involved in the production of melanin...
— lacking in colored pigments.
On August 28, 2010, a calico lobster with a mottled orange and black shell was reported to have been caught in Maine. Diane Cowan, a lobster scientist and founder of the Lobster Conservancy in Friendship
Friendship, Maine
Friendship is a town in Knox County, Maine, United States. The population was 1,204 at the 2000 census.-History:...
stated only albino lobsters are rarer, and orange lobsters such as these are a 1 in 30 million catch.
Several lobsters have been caught with different colorings on their left and right halves. For instance, on July 13, 2006, a Maine fisherman caught a brown and orange lobster, and submitted it to the local oceanarium, which had only seen three lobsters of this kind in 35 years. The chance of finding one is estimated at 1 in 50 million. All split-colored lobsters observed by Bob Bayer of the Lobster Institute in Maine have been hermaphroditic
Hermaphrodite
In biology, a hermaphrodite is an organism that has reproductive organs normally associated with both male and female sexes.Many taxonomic groups of animals do not have separate sexes. In these groups, hermaphroditism is a normal condition, enabling a form of sexual reproduction in which both...
.
Red lobsters are the usual result of a lobster being cooked. According to the Gulf of Maine Institute, however, there is a 1 in 10 million chance of catching one alive with that color.
Life cycle
The life cycleBiological life cycle
A life cycle is a period involving all different generations of a species succeeding each other through means of reproduction, whether through asexual reproduction or sexual reproduction...
of H. americanus is well understood. Mating
Mating
In biology, mating is the pairing of opposite-sex or hermaphroditic organisms for copulation. In social animals, it also includes the raising of their offspring. Copulation is the union of the sex organs of two sexually reproducing animals for insemination and subsequent internal fertilization...
only takes place shortly after the female has molted
Ecdysis
Ecdysis is the moulting of the cuticula in many invertebrates. This process of moulting is the defining feature of the clade Ecdysozoa, comprising the arthropods, nematodes, velvet worms, horsehair worms, rotifers, tardigrades and Cephalorhyncha...
, and her exoskeleton
Exoskeleton
An exoskeleton is the external skeleton that supports and protects an animal's body, in contrast to the internal skeleton of, for example, a human. In popular usage, some of the larger kinds of exoskeletons are known as "shells". Examples of exoskeleton animals include insects such as grasshoppers...
is still soft. The female releases a pheromone
Pheromone
A pheromone is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting outside the body of the secreting individual to impact the behavior of the receiving individual...
which causes the males to become less aggressive and to begin courtship
Courtship
Courtship is the period in a couple's relationship which precedes their engagement and marriage, or establishment of an agreed relationship of a more enduring kind. In courtship, a couple get to know each other and decide if there will be an engagement or other such agreement...
, which involves a courtship dance with claws closed. Eventually, the male inserts spermatophore
Spermatophore
A spermatophore or sperm ampulla is a capsule or mass created by males of various animal species, containing spermatozoa and transferred in entirety to the female's ovipore during copulation...
s (sperm
Sperm
The term sperm is derived from the Greek word sperma and refers to the male reproductive cells. In the types of sexual reproduction known as anisogamy and oogamy, there is a marked difference in the size of the gametes with the smaller one being termed the "male" or sperm cell...
packets) into the female's seminal receptacle using his first pleopods; the female may store the sperm for up to 15 months.
The female releases eggs
Egg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...
through her oviducts, and they pass the seminal receptacle and are fertilized
Fertilisation
Fertilisation is the fusion of gametes to produce a new organism. In animals, the process involves the fusion of an ovum with a sperm, which eventually leads to the development of an embryo...
by the stored sperm. They are then attached to the female's pleopods (swimmerets) using an adhesive, where they are cared for until they are ready to hatch. The female cleans the eggs regularly, and fans them with water to keep them oxygenated. The large telolecithal
Telolecithal
Telolecithal , also known as macrolecithal, refers to the uneven distribution of yolk in the cytoplasm of ovums found in birds, reptiles, and fish...
eggs may resemble the segments of a raspberry
Raspberry
The raspberry or hindberry is the edible fruit of a multitude of plant species in the genus Rubus, most of which are in the subgenus Idaeobatus; the name also applies to these plants themselves...
, and a female carrying eggs is said to be "in berry". Since this period lasts 10–11 months, berried females can be found at any time of year. In the waters off New England
New England
New England is a region in the northeastern corner of the United States consisting of the six states of Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, and Connecticut...
, the eggs are typically laid in July or August, and hatch the following May or June. The developing embryo
Embryo
An embryo is a multicellular diploid eukaryote in its earliest stage of development, from the time of first cell division until birth, hatching, or germination...
passes through several molts within the egg, before hatching as a metanauplius
Metanauplius
Metanauplius is an early larval stage of some crustaceans such as krill. It follows the nauplius stage.In sac-spawning krill, there is an intermediary phase called pseudometanauplius, a newly hatched form distinguished from older metanauplii by its extremely short abdomen...
larva. When the eggs hatch, the female releases them by waving her tail in the water, setting batches of larvae free.
The metanauplius of H. americanus is 1/3 in long, transparent, with large eyes and a long spine projecting from its head. It quickly molts, and the next three stages are similar, but larger. These molts take 10–20 days, during which the plankton
Plankton
Plankton are any drifting organisms that inhabit the pelagic zone of oceans, seas, or bodies of fresh water. That is, plankton are defined by their ecological niche rather than phylogenetic or taxonomic classification...
ic larvae are vulnerable to predation; only 1 in 1,000 is thought to survive to the juvenile stage. To reach the fourth stage – the post-larva – the larva undergoes metamorphosis
Metamorphosis
Metamorphosis is a biological process by which an animal physically develops after birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation...
, and subsequently shows a much greater resemblance to the adult lobster, is around 1/2 in long, and swims with its pleopods.
After the next molt, the lobster sinks to the ocean floor, and adopts a benthic
Benthos
Benthos is the community of organisms which live on, in, or near the seabed, also known as the benthic zone. This community lives in or near marine sedimentary environments, from tidal pools along the foreshore, out to the continental shelf, and then down to the abyssal depths.Many organisms...
lifestyle. It molts more and more infrequently, from an initial rate of ten times per year to once every few years. After one year, it is around 1 inch long, and after six years, it may weigh 1 pound (0.45359237 kg). By the time it reaches the minimum landing size
Minimum landing size
The minimum landing size is the smallest length at which it is legal to keep or sell a fish. What the MLS is depends on the species of fish. Sizes also vary around the world, as they are legal definitions which are defined by the local regulatory authority...
, an individual may have molted 25–27 times, and thereafter each molt may signal a 40%–50% increase in weight, and a 14% increase in carapace
Carapace
A carapace is a dorsal section of the exoskeleton or shell in a number of animal groups, including arthropods such as crustaceans and arachnids, as well as vertebrates such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron.-Crustaceans:In crustaceans, the...
length.
As food
One common way of serving lobster 'tail' (actually the abdomen
Abdomen
In vertebrates such as mammals the abdomen constitutes the part of the body between the thorax and pelvis. The region enclosed by the abdomen is termed the abdominal cavity...
) is with beef
Beef
Beef is the culinary name for meat from bovines, especially domestic cattle. Beef can be harvested from cows, bulls, heifers or steers. It is one of the principal meats used in the cuisine of the Middle East , Australia, Argentina, Brazil, Europe and the United States, and is also important in...
, known as surf and turf
Surf and turf
Surf and turf or surf 'n' turf is a main course in American cuisine which combines seafood and meat. It is particularly common in British or Irish pubs in North America and North American steakhouses, and typically includes lobster, Dublin Bay prawn, or shrimp, which may be grilled or breaded and...
. Lobsters have a greenish or brownish organ called the tomalley
Tomalley
Tomalley or lobster paste is the soft, green substance found in the body cavity of lobsters, that fulfills the functions of both the liver and the pancreas. Tomalley corresponds to the hepatopancreas in other arthropods...
that performs the functions of the liver
Liver
The liver is a vital organ present in vertebrates and some other animals. It has a wide range of functions, including detoxification, protein synthesis, and production of biochemicals necessary for digestion...
and pancreas
Pancreas
The pancreas is a gland organ in the digestive and endocrine system of vertebrates. It is both an endocrine gland producing several important hormones, including insulin, glucagon, and somatostatin, as well as a digestive organ, secreting pancreatic juice containing digestive enzymes that assist...
in a human, i.e., it filters out toxin
Toxin
A toxin is a poisonous substance produced within living cells or organisms; man-made substances created by artificial processes are thus excluded...
s from the body. Some diners consider it a delicacy, but others avoid it because they consider it a toxin
Toxin
A toxin is a poisonous substance produced within living cells or organisms; man-made substances created by artificial processes are thus excluded...
source or dislike eating innards.
A set of nutcrackers and a long, thin tool for pulling meat from inaccessible areas are suggested as basics, although more experienced diners can eat the animal with their bare hands or a simple tool (a fork, knife or rock). Eating a lobster can get messy, and most restaurants offer a lobster bib. Meat is generally contained in the larger claws and tails, and stays warm quite a while after being served. There is some meat in the legs and in the arms that connect the large claws to the body. There is also some small amount of meat just below the carapace around the thorax and in the smaller legs.
North American lobster industry
Most lobsters come from the northeastern coast of North America, with the Atlantic Provinces of Canada and the U.S. state
U.S. state
A U.S. state is any one of the 50 federated states of the United States of America that share sovereignty with the federal government. Because of this shared sovereignty, an American is a citizen both of the federal entity and of his or her state of domicile. Four states use the official title of...
of Maine
Maine
Maine is a state in the New England region of the northeastern United States, bordered by the Atlantic Ocean to the east and south, New Hampshire to the west, and the Canadian provinces of Quebec to the northwest and New Brunswick to the northeast. Maine is both the northernmost and easternmost...
being the largest producers. They are caught primarily using lobster trap
Lobster trap
Not to be confused with Lobster-tailed potA lobster trap or lobster pot is a portable trap that traps lobsters or crayfish and is used in lobster fishing. A lobster trap can hold several lobsters. Lobster traps are constructed of wire and wood. An opening permits the lobster to enter a tunnel of...
s, although lobsters are also harvested as bycatch
Bycatch
The term “bycatch” is usually used for fish caught unintentionally in a fishery while intending to catch other fish. It may however also indicate untargeted catch in other forms of animal harvesting or collecting...
by bottom trawlers
Bottom trawling
Bottom trawling is trawling along the sea floor. It is also often referred to as "dragging".The scientific community divides bottom trawling into benthic trawling and demersal trawling...
, fishermen using gillnet
Gillnet
Gillnetting is a common fishing method used by commercial and artisanal fishermen of all the oceans and in some freshwater and estuary areas. The gillnet also is used by fisheries scientists to monitor fish populations. Because gillnets can be so effective their use is closely monitored and...
s, and by scuba divers in some areas. Maine completely prohibits scuba divers from catching lobsters (violations could result in up to a $1000 fine). Massachusetts offers scuba divers lobster licenses for a fee, and they are only available to state residents. Rhode Island also requires divers to acquire a permit.
Lobster traps are rectangular cages made of vinyl-coated galvanized steel mesh or wood, with woven mesh entrances. These are baited and lowered to the sea floor. They allow a lobster to enter, but make it difficult for the larger specimens to turn around and exit. This allows the creatures to be captured alive. The traps, sometimes referred to as "pots", have a buoy
Buoy
A buoy is a floating device that can have many different purposes. It can be anchored or allowed to drift. The word, of Old French or Middle Dutch origin, is now most commonly in UK English, although some orthoepists have traditionally prescribed the pronunciation...
floating on the surface, and lobstermen check their traps between one and seven days after setting them. The inefficiency of the trapping system has inadvertently prevented the lobster population from being overfished. Lobsters can easily escape the trap, and will defend the trap against other lobsters because it is a source of food. An estimated 10% of lobsters that encounter a trap enter, and only 6% will actually be caught.
In the United States, the lobster industry is regulated
Regulation
Regulation is administrative legislation that constitutes or constrains rights and allocates responsibilities. It can be distinguished from primary legislation on the one hand and judge-made law on the other...
. Every lobsterman is required to use a lobster gauge to measure the distance from the lobster's eye socket to the end of its carapace: if the lobster is less than 3.25 inches (8.3 cm) long, it is too young to be sold and must be released back to the sea. There is also a legal maximum size of 5 in (12.7 cm) in Maine, meant to ensure the survival of a healthy breeding stock of adult males, but in parts of some states, such as Massachusetts, there is none. Also, traps must contain an escape hole or "vent", which allows juvenile lobsters and bycatch species to escape. The law in Maine and other states dictates a second large escape hole or "ghost panel" must be installed. This hole is held shut through use of biodegradable clips made of ferrous metal. Should the trap become lost, the trap eventually opens, allowing the catch to escape.
To protect known breeding females, lobsters caught carrying eggs are to be notched on a tail flipper (second from the right, if the lobster is right-side up and the tail is fully extended). Following this, the female cannot be kept or sold, and is commonly referred to as a "punch-tail" or as "v-notched". This notch remains for two molts of the lobster exoskeleton, providing harvest protection and continued breeding availability for up to five years.
Canada
Supreme Court of Canada
The Supreme Court of Canada is the highest court of Canada and is the final court of appeals in the Canadian justice system. The court grants permission to between 40 and 75 litigants each year to appeal decisions rendered by provincial, territorial and federal appellate courts, and its decisions...
ruled in favor of the First Nations and granted them unlimited rights to natural resources, based on an 18th-century treaty. The federal government tried to take licenses and quotas from the traditional fishermen, whose fishing quota had already dropped dramatically in the years before, and give them to the natives. Burnt Church, a reserve
Indian reserve
In Canada, an Indian reserve is specified by the Indian Act as a "tract of land, the legal title to which is vested in Her Majesty, that has been set apart by Her Majesty for the use and benefit of a band." The Act also specifies that land reserved for the use and benefit of a band which is not...
between Miramichi
Miramichi, New Brunswick
Miramichi is the largest city in northern New Brunswick, Canada. It is situated at the mouth of the Miramichi River where it enters Miramichi Bay...
and the Acadian town of Neguac, was the hub of these troubles. The tension increased and decreased with each fishing season, reaching its climax came in April 2003, when a riot broke in the port of Shippagan, where three native-owned fishing ships and a fish processing plant were burnt down. Since then, efforts have been made to bring Acadians and natives closer together, and the tension has slowly abated.
Management
American lobster tends to have a stable stock in northern (colder) waters, but gradually decreases in abundance moving southward. To manage lobster populations, more regulations and restrictions, geared towards achieving sustainable populations, are implemented gradually southward.Ecology
The American lobster thrives in cold, shallow waters where there are many rocks and other places to hide from predators. It typically lives at a depth of 4 metre, but can be found up to 480 m (1,574.8 ft) below the surface. It is both solitary and nocturnal, and feeds on fishFish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
, small crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
s, and mollusks
Mollusca
The Mollusca , common name molluscs or mollusksSpelled mollusks in the USA, see reasons given in Rosenberg's ; for the spelling mollusc see the reasons given by , is a large phylum of invertebrate animals. There are around 85,000 recognized extant species of molluscs. Mollusca is the largest...
.
Diseases
GaffkemiaGaffkaemia
Gaffkaemia is a bacterial disease of lobsters, caused by the Gram-positive lactic acid bacterium Aerococcus viridans var. homari.-Discovery:...
or red-tail is an extremely virulent infectious disease of lobsters caused by the bacterium Aerococcus viridans. It only requires a few bacterial cells to cause death of otherwise healthy lobsters. The "red tail" common name refers to a dark orange discoloration of the ventral abdomen of affected lobsters. This is, in fact, the haemolymph or blood seen through the thin ventral arthrodial membranes. The red discoloration comes from astaxanthin
Astaxanthin
Astaxanthin is a carotenoid. It belongs to a larger class of phytochemicals known as terpenes. It is classified as a xanthophyll, which means "yellow leaves". Like many carotenoids, it is a colorful, lipid-soluble pigment. Astaxanthin is found in microalgae, yeast, salmon, trout, krill, shrimp,...
, a carotenoid
Carotenoid
Carotenoids are tetraterpenoid organic pigments that are naturally occurring in the chloroplasts and chromoplasts of plants and some other photosynthetic organisms like algae, some bacteria, and some types of fungus. Carotenoids can be synthesized fats and other basic organic metabolic building...
pigment exported to the blood during times of stress. The same sign is also seen in other diseases of lobsters and appears to be a nonspecific stress response, possibly relating to the antioxidant and immunostimulatory properties of the astaxanthin molecule.
Paramoebiasis
Paramoebiasis
Paramoeba Parasite is a parasite that attacks the nervous system of lobsters. Lately, lobsters that have been pulled up in Western LIS have been dead with the parasite. Also, it caused almost all the deaths of the lobsters in 1999....
is an infectious disease of lobsters caused by infection with the sarcomastigophoran (ameba) Neoparamoeba
Neoparamoeba
Neoparamoeba is a genus of Amoebozoa....
pemaquidensis. This organism also causes amebic gill disease
Amoebic gill disease
-Introduction:Amoebic gill disease is a potentially fatal disease of some marine fish.It is caused by Neoparamoeba pemaguidensis and Neoparamoeba perurans, some of the most important amoebas in cultured fish....
in farmed Atlantic salmon
Atlantic salmon
The Atlantic salmon is a species of fish in the family Salmonidae, which is found in the northern Atlantic Ocean and in rivers that flow into the north Atlantic and the north Pacific....
, Salmo salar. Infection occurs throughout the tissues, causing granuloma
Granuloma
Granuloma is a medical term for a tiny collection of immune cells known as macrophages. Granulomas form when the immune system attempts to wall off substances that it perceives as foreign but is unable to eliminate. Such substances include infectious organisms such as bacteria and fungi as well as...
-like lesions, especially within the ventral nerve cord, the interstices of the hepatopancreas
Hepatopancreas
The hepatopancreas, digestive gland or midgut gland is an organ of the digestive tract of arthropods, molluscs and fish. It provides the functions which in mammals are provided separately by the liver and pancreas, including the production of digestive enzymes, and absorption of digested...
and the antennal gland. Paramoebiasis is strongly suspected to play a prominent role in the rapid die-off of American lobsters in Long Island Sound
Long Island Sound
Long Island Sound is an estuary of the Atlantic Ocean, located in the United States between Connecticut to the north and Long Island, New York to the south. The mouth of the Connecticut River at Old Saybrook, Connecticut, empties into the sound. On its western end the sound is bounded by the Bronx...
that occurred in the summer of 1999.
Systemic infections by the bacterium Vibrio fluvialis (or similar organisms) are reported to cause "limp lobster disease", wherein lobsters become lethargic and die.
Excretory calcinosis in American lobsters in Long Island Sound was described from an epizootic in 2002. The disease causes mineralized calculi
Calculus (medicine)
A calculus is a stone that forms in an organ or duct of the body. Formation of calculi is known as lithiasis...
to form in the antennal glands and gills. These cause a loss of surface area around the gills, and the lobster eventually asphyxiates. Several reasons have been proposed for the cause of a recent outbreak of the disease. The most generally attributed factor is an increased duration of warmer temperatures in the bottom of the Long Island Sound.
Taxonomy
The American lobster was first describedAlpha taxonomy
Alpha taxonomy is the discipline concerned with finding, describing and naming species of living or fossil organisms. This field is supported by institutions holding collections of these organisms, with relevant data, carefully curated: such institutes include natural history museums, herbaria and...
by Thomas Say
Thomas Say
Thomas Say was an American naturalist, entomologist, malacologist, herpetologist and carcinologist. A taxonomist, he is often considered to be the father of descriptive entomology in the United States. He described more than 1,000 new species of beetles and over 400 species of insects of other...
in 1817, with a type locality of "Long-branch
Long Branch, New Jersey
Long Branch is a city in Monmouth County, New Jersey, United States. As of the 2010 United States Census, the city population was 30,719.Long Branch was formed on April 11, 1867, as the Long Branch Commission, from portions of Ocean Township...
, part of the coast of New Jersey
New Jersey
New Jersey is a state in the Northeastern and Middle Atlantic regions of the United States. , its population was 8,791,894. It is bordered on the north and east by the state of New York, on the southeast and south by the Atlantic Ocean, on the west by Pennsylvania and on the southwest by Delaware...
". The name Say chose, however – "Astacus marinus" – was invalid as a junior homonym of Astacus marinus Fabricius, 1775, which is in turn a junior synonym
Synonym (taxonomy)
In scientific nomenclature, a synonym is a scientific name that is or was used for a taxon of organisms that also goes by a different scientific name. For example, Linnaeus was the first to give a scientific name to the Norway spruce, which he called Pinus abies...
of Homarus gammarus. The American lobster was given its current scientific name of Homarus americanus by Henri Milne-Edwards
Henri Milne-Edwards
Henri Milne-Edwards was an eminent French zoologist.Henri Milne-Edwards was the 27th child of William Edwards, an English planter and militia colonel in Jamaica and Elisabeth Vaux, a French. He was born in Bruges, Belgium, where his parents had retired. At that time, Bruges was a part of the...
in his 1837 work ("Natural History of the Crustacea"). The common name
Common name
A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...
preferred by the Food and Agriculture Organization
Food and Agriculture Organization
The Food and Agriculture Organization of the United Nations is a specialised agency of the United Nations that leads international efforts to defeat hunger. Serving both developed and developing countries, FAO acts as a neutral forum where all nations meet as equals to negotiate agreements and...
is "American lobster", but the species is also known locally as the "northern lobster", "Maine lobster" or simply "lobster".
External links
- The Lobster Institute at the University of MaineUniversity of MaineThe University of Maine is a public research university located in Orono, Maine, United States. The university was established in 1865 as a land grant college and is referred to as the flagship university of the University of Maine System...
- UNH Lobster Research: Monitoring The Offshore Lobster Fishery (lobsters.unh.edu)
- Rhode Island Sea Grant Fact Sheet