Rock Crab

red: Cancer productus yellow: Cancer anthonyi brown: Cancer antennarius

South Coast (Point Dume to Mexico border) Flakey fish Wild caught

rock_crab
Kirt Onthank

The Science

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Taxonomic description

  • Distinguished by their broad carapaces (outer shell) and claws [2]
  • Males have slender abdomens and are larger than females, which have broad abdomens where they carry eggs [1,2]
  • These crabs grow to different sizes, but rarely exceed 20 cm (8”) in width. [1] 
  • The red rock crab is brick red in color, the brown crab is dark brown with red spots, the yellow crab is light brown to pale yellow with no spots [2]

Distribution

  • Found along California’s coastline, from Baja California to Washington [2]
  • Though the three species ranges overlap, red rock crab is most common in northern California, the brown crab in central California and the yellow crab in southern California [1]

Life history

  • Grow in steps, molting the external shell at each step [1].
  • Mating occurs throughout the year, but peaks in Spring in California, and happens when females have soft shells just after molting [1].
  • Three months after mating, eggs are produced and then fertilized from a sperm packet left by the male during mating. The female carries the eggs for six to eight weeks until they hatch [1].
  • Larvae are planktonic and go through seven developmental molts before settling to the bottom as juveniles [1].

Habitat

  • Found mostly from the low intertidal to greater than 100 m (328 feet) depth [1].
  • Are commonly found in rocky substrates, except for the yellow rock crab which lives on sandy bottoms [1].
  • Act as predators and scavengers, using their claws to feed on shelled animals such as snails and clams [1]
  • As juveniles they are prey to commercial fishes and invertebrates like octopus [2].
  • Adults contribute to the diet of the threatened southern sea otter and other species [2].

The Fishery

Alisha Utter

Seasonal availability

  • Year-round [4]

Managing authority

  • As of 2002, the Fish and Game Commission was authorized to adopt regulations to manage annual general trap permits & catch regulations in accordance with the Marine Life Management Act of 1998 [5]

Gear type

  • Baited rectangular traps made of welded mesh or collapsible plastic attached to a buoy. 
  • Most commercial trapping occurs 27-73 m (90-240 ft) deep on open sandy bottoms or nearby rocky reefs [5]
  • Commercial crab boats are typically small & may set 200+ traps, which must each be raised & emptied every 96 hrs, weather permitting [5]
  • Prior to 1991, only the trapped crabs’ claws were harvested; clawless crabs were returned to the ocean with the hope that claws would regenerate. Today, it is illegal to harvest only claws and most are landed alive for sale at fresh fish markets [5]

Status of the fishery

  • There is little to no information on the fishery in California
  • One of the only major near shore fisheries with no restricted access and a low capital entry requirement; if these factors result in increased fishing pressure (high intensity for long periods of time), reductions in crab abundance and size may result [5].
  • The fishery is sustained by setting a minimum harvest on pre-reproductive crabs (<4.25 in. width at widest part of the body shell) and by including a 3.24 in escape ring on traps [4]
  • Beneficial future management efforts include: increased collaborative data collections, testing effects of a restricted access program in areas of high fishing intensity, gear modifications to reduce bycatch of other species [5]

Potential ecosystem impacts

  • No information is available for this particular fishery, but use of baited traps in general may lead to unintended catch, damage to seafloor in rough conditions, and entanglement of marine mammals in buoy lines. Solutions exist for most of these potential effects (e.g., release of bycatch, breakaway lines) [6]

The Seafood

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Edible portions

  • Claw meat is most commonly eaten, however the entire crab may be used in some recipes. 

Culinary uses

  • Crack the shell as you would an egg: be gentle to not destroy the contents [10]
  • Use the claws, or crack the entire shell & clear out guts, to cook in sauce or broth. 
  • Meat does not re-heat well, but freezes well so freeze until ready for use [11].
  • Easy preparation ideas: boil the claws in a broth containing your favorite seasoning and serve with melted butter or mayo 
  • Cook whole cleaned crab in tomato-based sauce for pasta or pizza
  • Cook claws in cioppino, paella, or seafood stew
  • Steam or boil claws, remove meat and use in crab cakes or casseroles.
  • Popular dishes include crab cakes, bisques and chowders, pastas, and even crab mac-n-cheese [12].

Nutritional information  

  • Hard shell crab, steamed [8]

Description of meat

  • Claw meat is very sweet

Toxicity report

  • No known contaminants.

Seasonal availability

  • Available fresh year-round [9] 

References

1. Leet, W.S. 2001. Rock Crab. California's Living Marine Resources: A Status Report. California Department of Fish and Wildlife. 

2. Carroll, J.C., R.N. Winn. 1989. Species profiles: life histories and environmental requirements of coastal fishes and invertebrates (Pacific Southwest)--brown rock crab, red rock crab, and yellow crab. U.S. Fish Wildl. Serv. Biol. Rep. 82(11.117). U.S. Army Corps of Engineers, TR EL-82-4. 16 pp

3. Schmitt, W. L. "The Marine Decapod Crustacea of California:." Google Books. N.p., n.d. Web. 7 Aug. 2013. 

4. California Fish and Game Commission. Marine Region.  2013. California Commercial Fishing: Commercial Fishing Digest. State of California. 

5. Parker, D.O. 2002. Annual Status of the Fisheries Report. California Dept of Fish & Wildlife. Marine Region. 

6. Monterey Bay Aquarium. 2013. Fishing Methods Fact Card: Traps and Pots. www.montereybayaquarium.org/cr/cr_seafoodwatch/content/media/MBA_Seafood...

7. Parker, D.O. 2001. Rock Crabs. California’s Living Marine Resources: A Status Report. Calif Dept of Fish & Game.

8.  Fatsecret. 2013. Steamed Hard Shell Crab. www.fatsecret.com/calories-nutrition/generic/crab-hard-shell-steamed

9. California Fish and Game Commission. Marine Region. 2013. California Commercial Fishing: Commercial Fishing Digest. State of California

10. http://vimeo.com/54756986

11. Shaw, H. 2013. Pacific Red & Rock Crabs: Cheap & Plentiful. Fish & Seafood Cooking. About.com. http://fishcooking.about.com/od/meetyourfish/p/Pacific_crab.htm.

12. Santa Montica Seafood. 2012. Introducing Pacific Stone Crab Meat!. www.santamonicaseafood.com/blog/2012/04/10/introducing-pacific-stone-cra....

13. Amistaadt, A.J. How to cook red rock crab. eHow.http://www.ehow.com/how_5057747_cook-red-rock-crab.html