Cancer pagurus

[[File:Cancer pagurus - Crabe dormeur - Tourteau - 004.jpg|thumb|right|The close-up]]

[[File:Cancer pagurus - Crabe dormeur - Tourteau - 004.jpg|thumb|right|The close-up]]

The first pereiopod is modified into a strong cheliped (claw-bearing leg); the claw's fingers, the [[arthropod leg|dactylus]] and propodus, are black at the tips.<ref name="Macrobenthos"/> The other pereiopods are covered with rows of short stiff [[seta]]e; the dactylus of each is black towards the tip, and ends in a sharp point.<ref name="Macrobenthos"/>

The first pereiopod is modified into a strong cheliped (claw-bearing leg); the claw's fingers, the [[arthropod leg|dactylus]] and propodus, are black at the tips. The other pereiopods are covered with rows of short stiff [[seta]]e; the dactylus of each is black towards the tip, and ends in a sharp point.<ref name="Macrobenthos"/>

From the front, the [[antenna (biology)|antennae]] and [[antennule]]s are visible. Beside these, the orbits are where the [[compound eye|eyes]] are situated.<ref name="Ingle"/> The [[Arthropod mouthparts|mouthparts]] comprise three pairs of [[maxilliped]]s, behind which are a pair of maxillae, a pair of maxillules, and finally the [[Mandible (arthropod mouthpart)|mandible]]s.<ref name="Ingle"/>

From the front, the [[antenna (biology)|antennae]] and [[antennule]]s are visible. Beside these, the orbits are where the [[compound eye|eyes]] are situated. The [[Arthropod mouthparts|mouthparts]] comprise three pairs of [[maxilliped]]s, behind which are a pair of maxillae, a pair of maxillules, and finally the [[Mandible (arthropod mouthpart)|mandible]]s.<ref name="Ingle"/>

==Lifecycle==

==Life cycle==

Reproduction occurs in winter; the male stands over the female and forms a cage with his legs protecting her while she [[ecdysis|moults]].<ref name="ARKive"/> [[Internal fertilization|Internal fertilisation]] takes place before the hardening of the new carapace, with the aid of two abdominal appendages (gonopods). After mating, the female retreats to a pit on the sea floor to lay her eggs.<ref name="ARKive"/> Between 250,000 and 3,000,000 fertilised eggs<ref name="BIOTIC">{{cite web |url=http://www.marlin.ac.uk/biotic/browse.php?sp=4129 |title=Species Information for ''Cancer pagurus'' |work=Biological Traits Information Catalogue |publisher=Marine Life Information Network |access-date=August 11, 2010}}</ref> are held under the female's abdomen up to eight months until they hatch.<ref name="ARKive"/>

Reproduction occurs in winter; the male stands over the female and forms a cage with his legs protecting her while she [[ecdysis|moults]]. [[Internal fertilization|Internal fertilisation]] takes place before the hardening of the new carapace, with the aid of two abdominal appendages (gonopods). After mating, the female retreats to a pit on the sea floor to lay her eggs.<ref name="ARKive"/> Between 250,000 and 3,000,000 fertilised eggs<ref name="BIOTIC">{{cite web |url=http://www.marlin.ac.uk/biotic/browse.php?sp=4129 |title=Species Information for ''Cancer pagurus'' |work=Biological Traits Information Catalogue |publisher=Marine Life Information Network |access-date=August 11, 2010}}</ref> are held under the female's abdomen up to eight months until they hatch.<ref name="ARKive"/>

[[File:Cancer pagurus (eggs).jpg|thumb|left|A female edible crab with eggs on scrap]]

[[File:Cancer pagurus (eggs).jpg|thumb|left|A female edible crab with eggs on scrap]]

The first developmental stage after hatching is a [[plankton]]ic larva (1&nbsp;mm) called the [[zoea]] that develops into a [[postlarva]] ([[megalopa]]), and finally a juvenile.<ref name="Eaton">{{cite journal |author1=D. R. Eaton |author2=J. Brown |author3=J. T. Addison |author4=S. P. Milligana |author5=L. J. Fernand |year=2003 |title=Edible crab (''Cancer pagurus'') larvae surveys off the east coast of England: implications for stock structure |journal=[[Fisheries Research]] |volume=65 |issue=1–3: Life Histories, Assessment and Management of Crustacean Fisheries |pages=191–199 |editor1=Oliver Tully |editor2=Juan Freire |editor3=Julian T. Addison |doi=10.1016/j.fishres.2003.09.036}}</ref> The first juvenile stage is characterised by a well-developed abdomen, which in time becomes reduced in size and folded under the sternum. Juveniles settle to the sea floor in the [[intertidal zone]], where they stay until they reach a [[carapace]] width of {{convert|60|–|70|mm|in|frac=8|abbr=on}}, and then migrate to deeper water.<ref name="BIOTIC"/> The growth rate in males slows from an increase in carapace width of 10&nbsp;mm per year before it is 8 years old, to 2&nbsp;mm per year thereafter.<ref name="BIOTIC"/> Females grow at about half the rate of males,<ref name="BIOTIC"/> probably due to the energetic demands of egg laying. [[Sexual maturity]] is reached at a carapace width of {{convert|127|mm|in|frac=8|abbr=on}} in females, and {{convert|110|mm|in|frac=8|abbr=on}} in males.<ref name="ARKive"/> [[Longevity]] is typically 25–30&nbsp;years, although exceptional individuals may live up to 100&nbsp;years.<ref>{{cite web |url=http://www.fishonline.org/fish/crab-brown-or-edible-214 |title=Edible crab, ''Cancer pagurus'' |work=Fishonline |publisher=[[Marine Conservation Society]] |access-date=August 23, 2010}}</ref>

The first developmental stage after hatching is a [[plankton]]ic larva (1&nbsp;mm) called the [[zoea]] that develops into a [[postlarva]] ([[megalopa]]), and finally a juvenile.<ref name="Eaton">{{cite journal |author1=D. R. Eaton |author2=J. Brown |author3=J. T. Addison |author4=S. P. Milligana |author5=L. J. Fernand |year=2003 |title=Edible crab (''Cancer pagurus'') larvae surveys off the east coast of England: implications for stock structure |journal=[[Fisheries Research]] |volume=65 |issue=1–3: Life Histories, Assessment and Management of Crustacean Fisheries |pages=191–199 |editor1=Oliver Tully |editor2=Juan Freire |editor3=Julian T. Addison |doi=10.1016/j.fishres.2003.09.036}}</ref> The first juvenile stage is characterised by a well-developed abdomen, which in time becomes reduced in size and folded under the sternum. Juveniles settle to the sea floor in the [[intertidal zone]], where they stay until they reach a [[carapace]] width of {{convert|60|–|70|mm|in|frac=8|abbr=on}}, and then migrate to deeper water. The growth rate in males slows from an increase in carapace width of 10&nbsp;mm per year before it is 8 years old, to 2&nbsp;mm per year thereafter. Females grow at about half the rate of males,<ref name="BIOTIC"/> probably due to the energetic demands of egg laying. [[Sexual maturity]] is reached at a carapace width of {{convert|127|mm|in|frac=8|abbr=on}} in females, and {{convert|110|mm|in|frac=8|abbr=on}} in males.<ref name="ARKive"/> [[Longevity]] is typically 25–30&nbsp;years, although exceptional individuals may live up to 100&nbsp;years.<ref>{{cite web |url=http://www.fishonline.org/fish/crab-brown-or-edible-214 |title=Edible crab, ''Cancer pagurus'' |work=Fishonline |publisher=[[Marine Conservation Society]] |access-date=August 23, 2010}}</ref>

==Distribution and ecology==

==Distribution and ecology==

[[File:Blue mussel clump.jpg|thumb|right|The [[blue mussel]], ''Mytilus edulis'', is a favourite food of ''C. pagurus''.]]

[[File:Blue mussel clump.jpg|thumb|right|The [[blue mussel]], ''Mytilus edulis'', is a favourite food of ''C. pagurus'']]

''C. pagurus'' is abundant throughout the northeast Atlantic as far as [[Norway]] in the north and [[North Africa]] in the south, on mixed coarse grounds, mud, and sand from the shallow [[sublittoral]] to depths around {{convert|100|m|ft fathom|sigfig=1|abbr=on}}.<ref name="Marlin"/> 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]].<ref name="ARKive">{{cite web |url=http://www.arkive.org/species/ARK/invertebrates_marine/Cancer_pagurus/more_info.html |archive-url=https://web.archive.org/web/20041226195347/http://www.arkive.org/species/ARK/invertebrates_marine/Cancer_pagurus/more_info.html |url-status=dead |archive-date=December 26, 2004 |title=Edible crab (''Cancer pagurus'') |publisher=[[ARKive]] |access-date=September 16, 2010}}</ref> Unconfirmed reports suggest that ''C. pagurus'' may also occur in the Mediterranean Sea and [[Black Sea]].<ref name="BIOTIC"/>

''C. pagurus'' is abundant throughout the northeast Atlantic as far as [[Norway]] in the north and [[North Africa]] in the south, on mixed coarse grounds, mud, and sand from the shallow [[sublittoral]] to depths around {{convert|100|m|ft fathom|sigfig=1|abbr=on}}.<ref name="Marlin"/> 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]].<ref name="ARKive">{{cite web |url=http://www.arkive.org/species/ARK/invertebrates_marine/Cancer_pagurus/more_info.html |archive-url=https://web.archive.org/web/20041226195347/http://www.arkive.org/species/ARK/invertebrates_marine/Cancer_pagurus/more_info.html |url-status=dead |archive-date=December 26, 2004 |title=Edible crab (''Cancer pagurus'') |publisher=[[ARKive]] |access-date=September 16, 2010}}</ref> Unconfirmed reports suggest that ''C. pagurus'' may also occur in the Mediterranean Sea and [[Black Sea]].<ref name="BIOTIC"/>

=== Diseases ===

=== Diseases ===

Compared to other commercially important crab species, relatively little is known about diseases of ''C. pagurus''.<ref name="Stentiford">{{cite journal |author=Grant D. Stentiford |year=2008 |title=Diseases of the European edible crab (''Cancer pagurus''): a review |journal=[[ICES Journal of Marine Science]] |volume=65 |issue=9 |pages=1578–1592 |doi=10.1093/icesjms/fsn134|doi-access=free }}</ref> Its parasites include [[virus]]es, such as the [[white spot syndrome]] virus, various [[bacteria]] that cause dark [[lesion]]s on the [[exoskeleton]], and ''[[Hematodinium]]''-like [[dinoflagellate]]s that cause "pink crab disease".<ref name="Stentiford"/> Other microscopic [[pathogen]]s include [[fungi]], [[microsporidia]]ns, [[paramyxea]]ns, and [[ciliate]]s. ''C. pagurus'' is also targeted by [[animal|metazoan]] parasites, including [[Trematoda|trematodes]] and parasitic [[barnacle]]s.<ref name="Stentiford"/> A number of [[Sessility (zoology)|sessile]] animals occasionally settle as [[epibiont]]s on the exoskeleton of ''C. pagurus'', including barnacles, [[sea anemone]]s, [[Serpulidae|serpulid]] [[polychaete]]s such as ''[[Janua pagenstecheri]]'', [[bryozoa]]ns, and [[Anomia (bivalve)|saddle oysters]].<ref name="Stentiford"/>

Compared to other commercially important crab species, relatively little is known about diseases of ''C. pagurus''. Its parasites include [[virus]]es, such as the [[white spot syndrome]] virus, various [[bacteria]] that cause dark [[lesion]]s on the [[exoskeleton]], and ''[[Hematodinium]]''-like [[dinoflagellate]]s that cause "pink crab disease". Other microscopic [[pathogen]]s include [[fungi]], [[microsporidia]]ns, [[paramyxea]]ns, and [[ciliate]]s. ''C. pagurus'' is also targeted by [[animal|metazoan]] parasites, including [[Trematoda|trematodes]] and parasitic [[barnacle]]s. A number of [[Sessility (zoology)|sessile]] animals occasionally settle as [[epibiont]]s on the exoskeleton of ''C. pagurus'', including barnacles, [[sea anemone]]s, [[Serpulidae|serpulid]] [[polychaete]]s such as ''[[Janua pagenstecheri]]'', [[bryozoa]]ns, and [[Anomia (bivalve)|saddle oysters]].<ref name="Stentiford">{{cite journal |author=Grant D. Stentiford |year=2008 |title=Diseases of the European edible crab (''Cancer pagurus''): a review |journal=[[ICES Journal of Marine Science]] |volume=65 |issue=9 |pages=1578–1592 |doi=10.1093/icesjms/fsn134 |doi-access=free}}</ref>

==Fishery==

==Fishery==

[[File:Lindisfarne Lobster Pots.JPG|thumb|left|Crab pots, [[Lindisfarne]], [[North Sea]]]]

[[File:Lindisfarne Lobster Pots.JPG|thumb|left|Crab pots, [[Lindisfarne]], [[North Sea]]]]

''C. pagurus'' is heavily [[Crab fisheries|exploited commercially]] throughout its range, being the most commercially important crab species in Western Europe.<ref name="ARKive"/> The crabs are caught using crab pots (similar to [[lobster trap|lobster pots]]), also known as creels, which are placed offshore and baited.<ref name="ARKive"/> The catch of ''C. pagurus'' has increased steadily, rising from 26,000&nbsp;tonnes in 1978 to 60,000&nbsp;t in 2007, of which more than 70% was caught around the [[British Isles]].<ref name="Seafish"/> The fishery is widely dispersed around the British and Irish coasts, and ''C. pagurus'' is thought to be [[overfishing|overfished]] across much of this area.<ref name="Seafish"/> Most of the edible crabs caught by the British fleet are exported live for sale in [[France]] and [[Spain]].<ref name="sourcing">{{cite web |url=http://www.seafish.org/pdf.pl?file=seafish/Documents/SeafishResponsibleSourcingGuide_CrabsLobsters.pdf |title=Responsible Sourcing Guide: Crabs & Lobsters |publisher=[[Sea Fish Industry Authority]] |date=August 2, 2009}}</ref>

''C. pagurus'' is heavily [[Crab fisheries|exploited commercially]] throughout its range, being the most commercially important crab species in Western Europe. The crabs are caught using crab pots (similar to [[lobster trap|lobster pots]]), also known as creels, which are placed offshore and baited.<ref name="ARKive"/> The catch of ''C. pagurus'' has increased steadily, rising from 26,000&nbsp;tonnes in 1978 to 60,000&nbsp;t in 2007, of which more than 70% was caught around the [[British Isles]]. The fishery is widely dispersed around the British and Irish coasts, and ''C. pagurus'' is thought to be [[overfishing|overfished]] across much of this area.<ref name="Seafish">{{cite book |author=Nautilus Consultants |url=http://www.seafish.org/pdf.pl?file=seafish/Documents/SR633_NautilusBrownCrabManagement_D123_Final.pdf |title=Future Management of Brown Crab in the UK and Ireland (IPF_D123) |date=December 2009 |publisher=[[Sea Fish Industry Authority]] |isbn=978-1-906634-36-0 |series=Seafish Report No. SR633}}</ref> Most of the edible crabs caught by the British fleet are exported live for sale in [[France]] and [[Spain]].<ref name="sourcing">{{cite web |url=http://www.seafish.org/pdf.pl?file=seafish/Documents/SeafishResponsibleSourcingGuide_CrabsLobsters.pdf |title=Responsible Sourcing Guide: Crabs & Lobsters |publisher=[[Sea Fish Industry Authority]] |date=August 2, 2009}}</ref>

A number of legal restrictions apply to the catching of ''C. pagurus''. Catching "berried" crabs (females carrying eggs) is illegal,<ref name="ARKive"/> but since ovigerous females remain in pits dug in the sediment and do not feed, fishing pressure does not affect the supply of larvae.<ref name="BIOTIC"/> [[Minimum landing size]]s (MLSs) for ''C. pagurus'' are set by both the [[European Union]] technical regulations and by the [[Government of the United Kingdom|UK government]].<ref name="Seafish">{{cite book |title=Future Management of Brown Crab in the UK and Ireland (IPF_D123) |series=Seafish Report No. SR633 |publisher=[[Sea Fish Industry Authority]] |author=Nautilus Consultants |date=December 2009 |isbn=978-1-906634-36-0 |url=http://www.seafish.org/pdf.pl?file=seafish/Documents/SR633_NautilusBrownCrabManagement_D123_Final.pdf }}</ref> Different minimum sizes are employed in different geographical areas, to reflect differences in the crab's growth rate across its range.<ref name="Seafish"/> In particular, the "[[Cromer]] crab" fishery along the coasts of [[Suffolk]], [[Norfolk]] and [[Lincolnshire]] is subject to an MLS of {{convert|115|mm|in|frac=8|abbr=on}}, rather than the {{convert|140|mm|in|frac=8|abbr=on}} MLS in most of the species' range. An intermediate value of {{convert|130|mm|in|frac=8|abbr=on}} is used in the rest of the North Sea between the [[56th parallel north|56°N]] and the [[Essex]]–[[Kent]] border, and in the [[Irish Sea]] south of [[55th parallel north|55°N]]. Around [[Devon]], [[Cornwall]], and the [[Isles of Scilly]], the MLS for males is different ({{convert|160|mm|in|frac=8|abbr=on|disp=or}}) from females ({{convert|140|mm|in|frac=8|abbr=on|disp=or}}).<ref name="Seafish"/> The Norwegian catch is 8,500 tons annually, compared to 20,000 tons in the United Kingdom, 13,000 tons in Ireland, 8,500 tons in France, and a total 45,000 tons globally.<ref>{{cite web |title=Taskekrabbe |trans-title=Edible crab |language=no |url=http://www.imr.no/__data/page/8431/2.7_Taskekrabbe.pdf |author=Knut Sunnanå |publisher=[[Norwegian Institute of Marine Research]] }}{{Dead link|date=November 2023 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> Recent studies have shown that edible crabs are negatively affected by electromagnetic fields emitted from sub-sea power cables around offshore wind farms.<ref>{{Cite journal|date=2018-06-01|title=Understanding the effects of electromagnetic field emissions from Marine Renewable Energy Devices (MREDs) on the commercially important edible crab, Cancer pagurus (L.)|journal=Marine Pollution Bulletin|language=en|volume=131|issue=Pt A|pages=580–588|doi=10.1016/j.marpolbul.2018.04.062|pmid=29886985|issn=0025-326X|last1=Scott|first1=Kevin|last2=Harsanyi|first2=Petra|last3=Lyndon|first3=Alastair R.|s2cid=47007844 }}</ref>

A number of legal restrictions apply to the catching of ''C. pagurus''. Catching "berried" crabs (females carrying eggs) is illegal,<ref name="ARKive"/> but since ovigerous females remain in pits dug in the sediment and do not feed, fishing pressure does not affect the supply of larvae.<ref name="BIOTIC"/> [[Minimum landing size]]s (MLSs) for ''C. pagurus'' are set by both the [[European Union]] technical regulations and by the [[Government of the United Kingdom|UK government]]. Different minimum sizes are employed in different geographical areas, to reflect differences in the crab's growth rate across its range. In particular, the "[[Cromer]] crab" fishery along the coasts of [[Suffolk]], [[Norfolk]] and [[Lincolnshire]] is subject to an MLS of {{convert|115|mm|in|frac=8|abbr=on}}, rather than the {{convert|140|mm|in|frac=8|abbr=on}} MLS in most of the species' range. An intermediate value of {{convert|130|mm|in|frac=8|abbr=on}} is used in the rest of the North Sea between the [[56th parallel north|56°N]] and the [[Essex]]–[[Kent]] border, and in the [[Irish Sea]] south of [[55th parallel north|55°N]]. Around [[Devon]], [[Cornwall]], and the [[Isles of Scilly]], the MLS for males is different ({{convert|160|mm|in|frac=8|abbr=on|disp=or}}) from females ({{convert|140|mm|in|frac=8|abbr=on|disp=or}}).<ref name="Seafish"/> The Norwegian catch is 8,500 tons annually, compared to 20,000 tons in the United Kingdom, 13,000 tons in Ireland, 8,500 tons in France, and a total 45,000 tons globally.<ref>{{cite web |title=Taskekrabbe |trans-title=Edible crab |language=no |url=http://www.imr.no/__data/page/8431/2.7_Taskekrabbe.pdf |author=Knut Sunnanå |publisher=[[Norwegian Institute of Marine Research]] }}{{Dead link|date=November 2023 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> Recent studies have shown that edible crabs are negatively affected by electromagnetic fields emitted from sub-sea power cables around offshore wind farms.<ref>{{Cite journal|date=2018-06-01|title=Understanding the effects of electromagnetic field emissions from Marine Renewable Energy Devices (MREDs) on the commercially important edible crab, Cancer pagurus (L.)|journal=Marine Pollution Bulletin|language=en|volume=131|issue=Pt A|pages=580–588|doi=10.1016/j.marpolbul.2018.04.062|pmid=29886985|issn=0025-326X|last1=Scott|first1=Kevin|last2=Harsanyi|first2=Petra|last3=Lyndon|first3=Alastair R.|s2cid=47007844 }}</ref>

==Cookery==

==Cookery==