Cancer Magister (Dana, 1852)
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Food and Agriculture Organization of the United Nations Fisheries and for a world without hunger Aquaculture Department Species Fact Sheets Cancer magister (Dana, 1852) Cancer magister: (click for more) Synonyms Cancer irroratus Randall, 1839. (misidentification) Metacarcinus magister A. Milne-Edwards, 1866. (misidentification) FAO Names En - Dungeness crab, Fr - Dormeur du Pacifique, Sp - Buey del Pacífico. 3Alpha Code: DUN Taxonomic Code: 2310901004 Diagnostic Features Broadly oval carapace approximately 2/3 as long as wide; front narrow with 3 teeth (excluding orbital angles), the middle one slightly exceeding others; anterolateral margins convex and divided into 9 teeth (excluding orbital angles) each acutely pointed at the anterior end. Teeth 1 to 7, included, increasing succesively in width; the most external tooth large, strongly projecting; notches between teeth continued on carapace as short. Short eyestalks with small orbits. Chelipeds subequal, moderately sized. Merus of cheliped with a distal and a subdistal spine above; wrist with a strong inner spine; hand with 6 carinae on upper outer surface, the uppermost spinuous. Colour beige to light brown with blue trim; often light orange below; fingers of chelipeds without dark colour. Can be confused with: Cancer magister is distinguished of the other Cancer species occurring in the same area often by size and by having different number of anterolateral teeth. This latter is the case of the smaller species Cancer gracilis Dana 1852 (7-8 anterolateral teeth) and Cancer oregonensis (Dana, 1852) (12-13). C. magister distinguishes from the large species Cancer productus Randall, 1839, the red rock crab, because the latter has 3 subequal frontal teeth (the middle one exceeding the others in C. magister). Geographical Distribution FAO Fisheries and Aquaculture Department Launch the Aquatic Species Distribution map viewer Pacific Northeast, from Monterrey Bay -California to Alaska. Habitat and Biology Shallow sandy areas of the sublittoral zone, from low waters to 90 m depth.Mature females at 100 mm carapace width. Hatching usually from mid-December through late January in California (later in Bristish Columbia and Alaska). Larvae distributed in the estuarine waters. Optimum hatching occurs at a salinity of about 15 ppt.Optimal temperature for larval crabs is between 10 and 14 °C. Size Males: minimum legal size of 165 mm cw (spine-to-spine); common sizes of 198 mm cw (126 carapace lenght). Females: carapace width from 91.6 to 172.9 mm in northern California waters; mature females at 100 mm cw. Interest to Fisheries Important commercial fisheries in California, Oregon, Washington, British Columbia and Alaska. It is a shellfish highly prized by both commercial and sport fishermen. Captured mainly with baited pots; also by hand, nets or even hooks and lines. Commercial fisheries management on the basis of sex, size, and season. Minimum legal size limit of 165 mm carapace width (males) in British Columbia. Commercial capture of females is prohibited and minimum size limits of commercial harvest of male crabs are designed to allow most males to mate at least once before capture. Annual exploitation rates exceeding 90%, results in a scarcity of large males that might reduce mating success among large females. Average catches of 17.000 t/year. Commercial landings in California have fluctuated widely, almost cyclically, over the past 30 years. The total catch reported for this species to FAO for 1999 was 18 880 t. The countries with the largest catches were USA (16 080 t) and Canada (2 800 t). Crabs are available for direct human consumption in a wide range of product forms. FAO Fisheries and Aquaculture Department Global Capture Production for species (tonnes) Source: FAO FishStat 60k 40k 20k 0k 1950 1960 1970 1980 1990 2000 2010 Cancer magister Local Names English : Common edible crab , Commercial crab , Edible crab , Market crab , Pacific edible crab . French : Crabe dormeur . German : Pazfischer taschenkrebs . Spanish : Cangrejo dungeness . Bibliography Gotshall, J.1977. Stomach contents of northern California Dungeness crabs, Cancer magister . California Fish Game. 63: 43-51 . Hankin, D.G., Butler, T.H., Wild, P.W. & Xue, Q. L.1997. Does intense fishing on males impair mating success of female Dungeness crabs? Canadian Journal of Fisheries and Aquatic Sciences. 54 (3): 655-669. Jensen, P.C., Orensanz, J.M. & Armstrong, D.A.1996. Structure of the female reproductive tract in the Dungeness crab (Cancer magister) and implications for the mating system.Biological Bulletin . 190:336-349. Rathbun, M.J.1930. The cancroid crabs of America of the families euryalidae, portunidae, atelecyclidae, cancridae and xanthidae. Smithsonian Institution Press. Washington, D.C. 609 p. Vera, J. 1992. Diccionario multilingüe de especies marinas para el mundo hispano.Ministerio de Agricultura, Pesca y Alimentación. Secretaria General Técnica. 1282 pp. FAO Fisheries and Aquaculture Department.