Crab fisheries
Encyclopedia
Crab fisheries are fisheries which capture or farm crabs. True crabs make up 20% of all crustacean
s caught and farmed worldwide, with about 1.4 million tonne
s being consumed annually. The horse crab, Portunus trituberculatus
accounts for one quarter of that total. Other important species include flower crabs (Portunus pelagicus
), snow crabs (Chionoecetes
) , blue crabs (Callinectes sapidus), edible or brown crabs (Cancer pagurus), Dungeness crab
(Metacarcinus magister) and mud crabs (Scylla serrata
), each of which provides more than 20,000 tonnes annually.
groups fishery catches using the ISSCAAP classification (International Standard Statistical Classification of Aquatic Animals and Plants). ISSCAAP has a group for crabs and sea-spiders, and another group for king crab
s and squat lobster
s.
The following table summarises crab production from 2000 to 2008, both caught wild and from aquaculture, in tonne
s.
, known as the horse crab, known as the gazami crab or Japanese blue crab, is the most widely fished
species
of crab
in the world, with over 300,000 tonne
s being caught annually, 98% of it off the coast of China
.
Horse crabs are found from Hokkaidō
to South India
, throughout the Malay Archipelago
and as far south as Australia
. In the Malay language
, it is known as ketam bunga or "flower crab". It lives on shallow sandy or muddy bottoms, less than 50 m deep, where it feeds on seaweed
s and predates upon small fish
, worm
s and bivalves
. The carapace
may reach 15 cm (6 inches) wide, and 7 cm (2¾ in) from front to back.
(known as flower crabs, blue crabs, blue swimmer crabs, blue manna crabs or sand crabs) is a large crab found in the intertidal estuaries
of the Indian
and Pacific Ocean
s (Asian coasts) and the Middle-Eastern
coast of the Mediterranean Sea
. The name flower crab is used in east Asian countries while the latter names are used in Australia. The crabs are widely distributed in eastern Africa
, Southeast Asia
, Japan
, Australia
and New Zealand
.
The carapace can be up to 20 cm wide. They stay buried under sand or mud most of the time, particularly during the daytime and winter. The species is commercially important throughout the Indo-Pacific where they may be sold as traditional hard shells, or as "soft shelled" crabs, which are considered a delicacy throughout Asia. The species is highly prized as the meat is almost as sweet as the blue crab, although P. pelagicus is physically much larger.
(known as snow crabs, spider crabs, queen crabs and other names) live in the cold waters of the northern Pacific
and Atlantic Ocean
.
Snow crab are caught as far north as the Arctic Ocean
, from Newfoundland to Greenland
in the Atlantic Ocean
, and across the Pacific Ocean
, including the Sea of Japan
, the Bering Sea
, the Gulf of Alaska
, Norton Sound
, and even as far south as California
for Chionoecetes bairdi. Fishing for opilio (and rarely bairdi) crab has been the focus of the second half of all four seasons of Deadliest Catch
on the Discovery Channel
.
, located in Maryland
and Virginia, is famous for its "blue crabs", Callinectes sapidus. In 1993, the combined harvest of the blue crabs was valued at around 100 million U.S. dollars. Over the years the harvests of the blue crab dropped; in 2000, the combined harvest was around 45 million dollars.
While blue crabs remain a popular food in the Chesapeake Bay area, the Bay is not capable of meeting local demand. Crabs are shipped into the region from North Carolina
, Louisiana
, Florida
and Texas
to supplement the local harvest.
found in the North Sea
, North Atlantic
and the Mediterranean Sea
. It is a robust crab of a reddish-brown colour, having an oval carapace
with a characteristic "pie crust" edge and black tips to the claws. Mature adults may have a carapace width of up to about 25 cm and weigh up to 3 kg.
The edible crab is abundant throughout the northeast Atlantic
as far as Norway
in the north and northern Africa
in the south, on mixed coarse grounds, mud and sand from shallow sublittoral to about 100 m. It is frequently found inhabiting cracks and holes in rocks but occasionally also in open areas. Smaller specimens may be found under rocks in the littoral zone.
Edible crabs are heavily exploited commercially throughout their range. It is illegal to catch crabs of too small a size around the coast of Britain, a conservation measure brought in the 1870s. Crabs with a shell diameter of less than 100 mm should not be taken.
inhabits eelgrass
beds and water bottoms from the Aleutian Islands in Alaska
to Santa Cruz, California
. Its binomial name, Cancer magister, simply means "master crab" in Latin
.
They measure as much as 25 cm (9.8 in) in some areas off the coast of Washington, but typically are under 20 cm (7.9 in). They are a popular delicacy, and are the most commercially important crab in the Pacific Northwest
, as well as the western states generally.
They are named after Dungeness, Washington
, which is located approximately five miles north of Sequim
and 15 miles east of Port Angeles
. The annual Dungeness Crab and Seafood Festival is held in Port Angeles each October.
Dungeness crab have recently been found in the Atlantic Ocean
, far from their known range, raising concern about their possible effects on the local wildlife.
(known as mud crab, or more ambiguously as mangrove crab
or black crab) is an economically important crab species
found in the estuaries
and mangrove
s of Africa
, Australia
and Asia
. In their most common form, the shell colour varies from a deep, mottled green to very dark brown. Generally cooked with their shells on, when they moult
their shells, they can be served as a seafood delicacy, one of many types of soft shell crab
. They are among the tastiest crab species and have a huge demand in South Asia
n countries where they are often bought alive in the markets. In the northern states of Australia
and especially Queensland
, mud crabs are relatively common and generally prized above other seafood within the general public.
(European spider crabs) are a species of migratory crabs found in the north-east Atlantic and the Mediterranean Sea. They are the subject of commercial fishery
, with about 5,000 tonne
s caught annually, 70% off the coast of France
, 10% off the coast of the United Kingdom
, 6% from the Channel Islands
, 3% from each of Spain
and Ireland
, 2% from Croatia
, 1% from Portugal
, and the remainder from Serbia and Montenegro
, Denmark
and Morocco
, although official production figures are open to doubt. The European Union
imposes a minimum landing size
of 120 mm for M. squinado, and some individual countries have other regulations, such as a ban on landing egg-bearing females in Spain and a closed season in France and the Channel Islands.
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 caught and farmed worldwide, with about 1.4 million tonne
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...
s being consumed annually. The horse crab, Portunus trituberculatus
Portunus trituberculatus
Portunus trituberculatus, the gazami crab, Japanese blue crab or horse crab, is the most widely fished species of crab in the world. It is found off the coasts of East Asia and is closely related to Portunus pelagicus.-Fishery:P...
accounts for one quarter of that total. Other important species include flower crabs (Portunus pelagicus
Portunus pelagicus
Portunus pelagicus, also known as the flower crab, blue crab, blue swimmer crab, blue manna crab or sand crab, is a large crab found in the intertidal estuaries of the Indian and Pacific Oceans and the Middle-Eastern coast of the Mediterranean Sea. The name "flower crab" is used in east Asian...
), snow crabs (Chionoecetes
Chionoecetes
Chionoecetes is a genus of crabs that live in the northern Pacific and Atlantic Oceans.Other names for crabs in this genus include "queen crab" and "spider crab" – they are known by different names in different areas of the world....
) , blue crabs (Callinectes sapidus), edible or brown crabs (Cancer pagurus), Dungeness crab
Dungeness crab
The Dungeness crab, Metacarcinus magister , is a species of crab that inhabits eelgrass beds and water bottoms on the west coast of North America. It typically grows to across the carapace and is a popular seafood...
(Metacarcinus magister) and mud crabs (Scylla serrata
Scylla serrata
Scylla serrata is an economically important crab species found in the estuaries and mangroves of Africa, Australia and Asia. In their most common form, the shell colour varies from a deep, mottled green to very dark brown...
), each of which provides more than 20,000 tonnes annually.
Commercial catch
The FAOFood 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...
groups fishery catches using the ISSCAAP classification (International Standard Statistical Classification of Aquatic Animals and Plants). ISSCAAP has a group for crabs and sea-spiders, and another group for king crab
King crab
King crabs, also called stone crabs, are a superfamily of crab-like decapod crustaceans chiefly found in cold seas. Because of their large size and the taste of their meat, many species are widely caught and sold as food, the most common being the red king crab, Paralithodes camtschaticus.King...
s and squat lobster
Squat lobster
Squat lobsters are decapod crustaceans of the families Galatheidae, Chirostylidae and Kiwaidae, including the common genera Galathea and Munida. They are not lobsters at all, but are more closely related to porcelain crabs, hermit crabs and then, more distantly, true crabs...
s.
- Crabs and sea-spiders are defined as including "Atlantic rock crab, black stone crab, blue crab, blue swimming crab, dana swimcrab, dungeness crab, edible crab, cazami crab, geryons nei, green crab, hair crab, harbour spidercrab, Indo-Pacific swamp crab, jonah crab, marine crabs nei, Mediterranean shore crab, Pacific rock crab, portunus swimcrabs nei, queen crab, red crab, spinous spider crab, swimcrabs nei, and tanner crabs nei".
The following table summarises crab production from 2000 to 2008, both caught wild and from aquaculture, in tonne
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...
s.
Commercial crab production in tonnes | |||||||||
---|---|---|---|---|---|---|---|---|---|
Group | 2000 | 2001 | 2002 | 2003 | 2004 | 2005 | 2006 | 2007 | 2008 |
Capture | 1,046,269 | 1,034,898 | 1,061,697 | 1,246,889 | 1,252,260 | 1,233,523 | 1,302,069 | 1,300,559 | 1,319,953 |
Aquaculture | 125,501 | 145,130 | 171,979 | 167,533 | 178,838 | 195,995 | 198,258 | 231,065 | 240,781 |
Total | 1,171,770 | 1,180,028 | 1,233,676 | 1,414,422 | 1,431,098 | 1,429,518 | 1,500,327 | 1,531,624 | 1,560,734 |
Portunus trituberculatus
Portunus trituberculatusPortunus trituberculatus
Portunus trituberculatus, the gazami crab, Japanese blue crab or horse crab, is the most widely fished species of crab in the world. It is found off the coasts of East Asia and is closely related to Portunus pelagicus.-Fishery:P...
, known as the horse crab, known as the gazami crab or Japanese blue crab, is the most widely fished
Fishery
Generally, a fishery is an entity engaged in raising or harvesting fish which is determined by some authority to be a fishery. According to the FAO, a fishery is typically defined in terms of the "people involved, species or type of fish, area of water or seabed, method of fishing, class of boats,...
species
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 crab
Crab
True crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" , or where the reduced abdomen is entirely hidden under the thorax...
in the world, with over 300,000 tonne
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...
s being caught annually, 98% of it off the coast of China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
.
Horse crabs are found from Hokkaidō
Hokkaido
, formerly known as Ezo, Yezo, Yeso, or Yesso, is Japan's second largest island; it is also the largest and northernmost of Japan's 47 prefectural-level subdivisions. The Tsugaru Strait separates Hokkaido from Honshu, although the two islands are connected by the underwater railway Seikan Tunnel...
to South India
South India
South India is the area encompassing India's states of Andhra Pradesh, Karnataka, Kerala and Tamil Nadu as well as the union territories of Lakshadweep and Pondicherry, occupying 19.31% of India's area...
, throughout the Malay Archipelago
Malay Archipelago
The Malay Archipelago refers to the archipelago between mainland Southeastern Asia and Australia. The name was derived from the anachronistic concept of a Malay race....
and as far south as Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
. In the Malay language
Malay language
Malay is a major language of the Austronesian family. It is the official language of Malaysia , Indonesia , Brunei and Singapore...
, it is known as ketam bunga or "flower crab". It lives on shallow sandy or muddy bottoms, less than 50 m deep, where it feeds on seaweed
Seaweed
Seaweed is a loose, colloquial term encompassing macroscopic, multicellular, benthic marine algae. The term includes some members of the red, brown and green algae...
s and predates upon small fish
Fish
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...
, worm
Worm
The term worm refers to an obsolete taxon used by Carolus Linnaeus and Jean-Baptiste Lamarck for all non-arthropod invertebrate animals, and stems from the Old English word wyrm. Currently it is used to describe many different distantly-related animals that typically have a long cylindrical...
s and bivalves
Bivalvia
Bivalvia is a taxonomic class of marine and freshwater molluscs. This class includes clams, oysters, mussels, scallops, and many other families of molluscs that have two hinged shells...
. The 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...
may reach 15 cm (6 inches) wide, and 7 cm (2¾ in) from front to back.
Portunus pelagicus
Portunus pelagicusPortunus pelagicus
Portunus pelagicus, also known as the flower crab, blue crab, blue swimmer crab, blue manna crab or sand crab, is a large crab found in the intertidal estuaries of the Indian and Pacific Oceans and the Middle-Eastern coast of the Mediterranean Sea. The name "flower crab" is used in east Asian...
(known as flower crabs, blue crabs, blue swimmer crabs, blue manna crabs or sand crabs) is a large crab found in the intertidal estuaries
Estuary
An estuary is a partly enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea....
of the Indian
Indian Ocean
The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...
and Pacific Ocean
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
s (Asian coasts) and the Middle-Eastern
Middle East
The Middle East is a region that encompasses Western Asia and Northern Africa. It is often used as a synonym for Near East, in opposition to Far East...
coast of the Mediterranean Sea
Mediterranean Sea
The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...
. The name flower crab is used in east Asian countries while the latter names are used in Australia. The crabs are widely distributed in eastern Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
, Southeast Asia
Southeast Asia
Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...
, Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
, Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
and New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
.
The carapace can be up to 20 cm wide. They stay buried under sand or mud most of the time, particularly during the daytime and winter. The species is commercially important throughout the Indo-Pacific where they may be sold as traditional hard shells, or as "soft shelled" crabs, which are considered a delicacy throughout Asia. The species is highly prized as the meat is almost as sweet as the blue crab, although P. pelagicus is physically much larger.
Chionoecetes
Species of ChionoecetesChionoecetes
Chionoecetes is a genus of crabs that live in the northern Pacific and Atlantic Oceans.Other names for crabs in this genus include "queen crab" and "spider crab" – they are known by different names in different areas of the world....
(known as snow crabs, spider crabs, queen crabs and other names) live in the cold waters of the northern Pacific
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
and Atlantic Ocean
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...
.
Snow crab are caught as far north as the Arctic Ocean
Arctic Ocean
The Arctic Ocean, located in the Northern Hemisphere and mostly in the Arctic north polar region, is the smallest and shallowest of the world's five major oceanic divisions...
, from Newfoundland to Greenland
Greenland
Greenland is an autonomous country within the Kingdom of Denmark, located between the Arctic and Atlantic Oceans, east of the Canadian Arctic Archipelago. Though physiographically a part of the continent of North America, Greenland has been politically and culturally associated with Europe for...
in the Atlantic Ocean
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...
, and across the Pacific Ocean
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
, including the Sea of Japan
Sea of Japan
The Sea of Japan is a marginal sea of the western Pacific Ocean, between the Asian mainland, the Japanese archipelago and Sakhalin. It is bordered by Japan, North Korea, Russia and South Korea. Like the Mediterranean Sea, it has almost no tides due to its nearly complete enclosure from the Pacific...
, the Bering Sea
Bering Sea
The Bering Sea is a marginal sea of the Pacific Ocean. It comprises a deep water basin, which then rises through a narrow slope into the shallower water above the continental shelves....
, the Gulf of Alaska
Gulf of Alaska
The Gulf of Alaska is an arm of the Pacific Ocean defined by the curve of the southern coast of Alaska, stretching from the Alaska Peninsula and Kodiak Island in the west to the Alexander Archipelago in the east, where Glacier Bay and the Inside Passage are found.The entire shoreline of the Gulf is...
, Norton Sound
Norton Sound
Norton Sound is an inlet of the Bering Sea on the western coast of the U.S. state of Alaska, south of the Seward Peninsula. It is about 240 km long and 200 km wide. The Yukon River delta forms a portion of the south shore and water from the Yukon influences this body of water...
, and even as far south as California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
for Chionoecetes bairdi. Fishing for opilio (and rarely bairdi) crab has been the focus of the second half of all four seasons of Deadliest Catch
Deadliest Catch
Deadliest Catch is a documentary/reality television series produced by Original Productions for the Discovery Channel. It portrays the real life events aboard fishing vessels in the Bering Sea during the Alaskan king crab and C. opilio crab fishing seasons.The Aleutian Islands port of Dutch Harbor,...
on the Discovery Channel
Discovery Channel
Discovery Channel is an American satellite and cable specialty channel , founded by John Hendricks and distributed by Discovery Communications. It is a publicly traded company run by CEO David Zaslav...
.
Callinectes sapidus
The Chesapeake BayChesapeake Bay
The Chesapeake Bay is the largest estuary in the United States. It lies off the Atlantic Ocean, surrounded by Maryland and Virginia. The Chesapeake Bay's drainage basin covers in the District of Columbia and parts of six states: New York, Pennsylvania, Delaware, Maryland, Virginia, and West...
, located in 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...
and Virginia, is famous for its "blue crabs", Callinectes sapidus. In 1993, the combined harvest of the blue crabs was valued at around 100 million U.S. dollars. Over the years the harvests of the blue crab dropped; in 2000, the combined harvest was around 45 million dollars.
While blue crabs remain a popular food in the Chesapeake Bay area, the Bay is not capable of meeting local demand. Crabs are shipped into the region from 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...
, Louisiana
Louisiana
Louisiana is a state located in the southern region of the United States of America. Its capital is Baton Rouge and largest city is New Orleans. Louisiana is the only state in the U.S. with political subdivisions termed parishes, which are local governments equivalent to counties...
, Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
and Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...
to supplement the local harvest.
Cancer pagurus
Cancer pagurus, the edible crab or brown crab, is a species of crabCrab
True crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" , or where the reduced abdomen is entirely hidden under the thorax...
found in the North Sea
North Sea
In the southwest, beyond the Straits of Dover, the North Sea becomes the English Channel connecting to the Atlantic Ocean. In the east, it connects to the Baltic Sea via the Skagerrak and Kattegat, narrow straits that separate Denmark from Norway and Sweden respectively...
, North Atlantic
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...
and the Mediterranean Sea
Mediterranean Sea
The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...
. It is a robust crab of a reddish-brown colour, having an oval 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...
with a characteristic "pie crust" edge and black tips to the claws. Mature adults may have a carapace width of up to about 25 cm and weigh up to 3 kg.
The edible crab is abundant throughout the northeast Atlantic
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...
as far as Norway
Norway
Norway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...
in the north and northern Africa
North Africa
North Africa or Northern Africa is the northernmost region of the African continent, linked by the Sahara to Sub-Saharan Africa. Geopolitically, the United Nations definition of Northern Africa includes eight countries or territories; Algeria, Egypt, Libya, Morocco, South Sudan, Sudan, Tunisia, and...
in the south, on mixed coarse grounds, mud and sand from shallow sublittoral to about 100 m. It is frequently found inhabiting cracks and holes in rocks but occasionally also in open areas. Smaller specimens may be found under rocks in the littoral zone.
Edible crabs are heavily exploited commercially throughout their range. It is illegal to catch crabs of too small a size around the coast of Britain, a conservation measure brought in the 1870s. Crabs with a shell diameter of less than 100 mm should not be taken.
Dungeness crabs
The Dungeness crabDungeness crab
The Dungeness crab, Metacarcinus magister , is a species of crab that inhabits eelgrass beds and water bottoms on the west coast of North America. It typically grows to across the carapace and is a popular seafood...
inhabits eelgrass
Zostera
Zostera is a small genus of widely distributed seagrass, commonly called marine eelgrass or simply eelgrass . The genus Zostera contains sixteen species.-Ecology:Zostera is found on sandy substrates or in estuaries submerged or partially floating...
beds and water bottoms from the Aleutian Islands in Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
to Santa Cruz, California
Santa Cruz, California
Santa Cruz is the county seat and largest city of Santa Cruz County, California in the US. As of the 2010 U.S. Census, Santa Cruz had a total population of 59,946...
. Its binomial name, Cancer magister, simply means "master crab" in Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
.
They measure as much as 25 cm (9.8 in) in some areas off the coast of Washington, but typically are under 20 cm (7.9 in). They are a popular delicacy, and are the most commercially important crab in the Pacific Northwest
Pacific Northwest
The Pacific Northwest is a region in northwestern North America, bounded by the Pacific Ocean to the west and, loosely, by the Rocky Mountains on the east. Definitions of the region vary and there is no commonly agreed upon boundary, even among Pacific Northwesterners. A common concept of the...
, as well as the western states generally.
They are named after Dungeness, Washington
Dungeness, Washington
Dungeness is an unincorporated community in Clallam County, Washington, United States, located north of Sequim. Dungeness crab is named after the town of Dungeness, which is located on the Strait of Juan de Fuca...
, which is located approximately five miles north of Sequim
Sequim, Washington
Sequim is a city in Clallam County, Washington, United States. The 2010 US Census counted a population of 6,606. Sequim is located along the Dungeness River near the base of the Olympic Mountains...
and 15 miles east of Port Angeles
Port Angeles, Washington
Port Angeles is a city in and the county seat of Clallam County, Washington, United States. The population was 19,038 at the 2010 census. The area's harbor was dubbed Puerto de Nuestra Señora de los Ángeles by Spanish explorer Francisco de Eliza in 1791, but by the mid-19th century the name had...
. The annual Dungeness Crab and Seafood Festival is held in Port Angeles each October.
Dungeness crab have recently been found in the Atlantic Ocean
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...
, far from their known range, raising concern about their possible effects on the local wildlife.
Scylla serrata
Scylla serrataScylla serrata
Scylla serrata is an economically important crab species found in the estuaries and mangroves of Africa, Australia and Asia. In their most common form, the shell colour varies from a deep, mottled green to very dark brown...
(known as mud crab, or more ambiguously as mangrove crab
Mangrove crab
Mangrove crabs are crabs that live among mangroves, and may belong to many different species and even families. They have been shown to be ecologically significant in many ways. They keep much of the energy within the forest by burying and consuming leaf litter. Along with burrowing in the ground,...
or black crab) is an economically important crab species
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...
found in the estuaries
Estuary
An estuary is a partly enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea....
and mangrove
Mangrove
Mangroves are various kinds of trees up to medium height and shrubs that grow in saline coastal sediment habitats in the tropics and subtropics – mainly between latitudes N and S...
s of Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
, Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
and Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
. In their most common form, the shell colour varies from a deep, mottled green to very dark brown. Generally cooked with their shells on, when they moult
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...
their shells, they can be served as a seafood delicacy, one of many types of soft shell crab
Soft shell crab
Soft-shell crab is a culinary term for crabs which have recently molted their old exoskeleton and are still soft.In the United States, the main species is the "blue crab", Callinectes sapidus, which appears in markets from April to September...
. They are among the tastiest crab species and have a huge demand in South Asia
South Asia
South Asia, also known as Southern Asia, is the southern region of the Asian continent, which comprises the sub-Himalayan countries and, for some authorities , also includes the adjoining countries to the west and the east...
n countries where they are often bought alive in the markets. In the northern states of Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
and especially Queensland
Queensland
Queensland is a state of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory, South Australia and New South Wales to the west, south-west and south respectively. To the east, Queensland is bordered by the Coral Sea and Pacific Ocean...
, mud crabs are relatively common and generally prized above other seafood within the general public.
Maja squinado
Maja squinadoMaja squinado
Maja squinado is a species of migratory crab found in the north-east Atlantic and the Mediterranean Sea.-Diet:M...
(European spider crabs) are a species of migratory crabs found in the north-east Atlantic and the Mediterranean Sea. They are the subject of commercial fishery
Fishery
Generally, a fishery is an entity engaged in raising or harvesting fish which is determined by some authority to be a fishery. According to the FAO, a fishery is typically defined in terms of the "people involved, species or type of fish, area of water or seabed, method of fishing, class of boats,...
, with about 5,000 tonne
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...
s caught annually, 70% off the coast of France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
, 10% off the coast of the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
, 6% from the Channel Islands
Channel Islands
The Channel Islands are an archipelago of British Crown Dependencies in the English Channel, off the French coast of Normandy. They include two separate bailiwicks: the Bailiwick of Guernsey and the Bailiwick of Jersey...
, 3% from each of Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...
and Ireland
Ireland
Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...
, 2% from Croatia
Croatia
Croatia , officially the Republic of Croatia , is a unitary democratic parliamentary republic in Europe at the crossroads of the Mitteleuropa, the Balkans, and the Mediterranean. Its capital and largest city is Zagreb. The country is divided into 20 counties and the city of Zagreb. Croatia covers ...
, 1% from Portugal
Portugal
Portugal , officially the Portuguese Republic is a country situated in southwestern Europe on the Iberian Peninsula. Portugal is the westernmost country of Europe, and is bordered by the Atlantic Ocean to the West and South and by Spain to the North and East. The Atlantic archipelagos of the...
, and the remainder from Serbia and Montenegro
Serbia and Montenegro
Serbia and Montenegro was a country in southeastern Europe, formed from two former republics of the Socialist Federal Republic of Yugoslavia : Serbia and Montenegro. Following the breakup of Yugoslavia, it was established in 1992 as a federation called the Federal Republic of Yugoslavia...
, Denmark
Denmark
Denmark is a Scandinavian country in Northern Europe. The countries of Denmark and Greenland, as well as the Faroe Islands, constitute the Kingdom of Denmark . It is the southernmost of the Nordic countries, southwest of Sweden and south of Norway, and bordered to the south by Germany. Denmark...
and Morocco
Morocco
Morocco , officially the Kingdom of Morocco , is a country located in North Africa. It has a population of more than 32 million and an area of 710,850 km², and also primarily administers the disputed region of the Western Sahara...
, although official production figures are open to doubt. The European Union
European Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...
imposes a 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...
of 120 mm for M. squinado, and some individual countries have other regulations, such as a ban on landing egg-bearing females in Spain and a closed season in France and the Channel Islands.