Dungeness Crab | Oceana Canada

Canadian Marine Life Encyclopedia

Dungeness Crab

Cancer magister

Also known as

Dungles, market crab

Distribution

Sub-polar & temperate waters of northeast Pacific, from the Aleutian Islands to southern California

Ecosystem/Habitat

Soft bottoms

Feeding Habits

Foraging omnivore

Conservation Status

Not listed

Taxonomy

Infraorder Brachyura (crabs with short “tail” hidden under the body); Family Cancridae (crabs, most

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Dungeness crabs are a crustacean species. Like all arthropods, they have an “exoskeleton” (a skeleton on the outside of their body), segmented body parts and jointed appendages. Because their skeleton is outside of their body, arthropods must grow a new exoskeleton and shed their old one as they grow; a process called molting. When people find empty Dungeness crab shells strewn along beaches, they often mistake them for dead crabs, when in fact they are the old exoskeletons of crabs that are still alive, but are now a little bit larger than before.

The hard outer body, or “carapace,” of Dungeness crabs is oval shaped and typically yellow-brown to purplish. They have a pair of claws closest to their head, followed by four pairs of walking legs behind the claws. Their claws are serrated, with light-coloured tips and a pronounced hook that distinguishes them from other crab species. Adult crabs typically weigh from 0.7-1.4 kilograms, and they can grow to two kilograms; however they don’t typically reach this size due to high fishing pressure.

Dungeness crabs reach sexual maturity at around two years old for females, and three years old for males. In their second year, females will molt their exoskeleton between May and August and then mate in shallower, inshore water. After mating, females will move toward deeper waters, carrying the male’s sperm until the eggs are fully developed around October or November. She will then extrude the eggs where they become fertilized and stick them to her underside, under a tail-like appendage that is hidden under her belly. Females then typically bury themselves in the sand until the eggs are developed and ready to hatch in the late winter.

The newly hatched larvae float around the water column for about four months, until they molt into their juvenile forms and settle into intertidal (zone exposed to air at low tide but underwater at high tide) and shallow subtidal (zone below the level of low tide) habitats for their first year of life. Dungeness crabs can live for up to 10 years.

Dungeness crabs are caught by pot or trap fisheries all over the northeast Pacific coast of North America. The indigenous fishery in British Columbia preceded the arrival of European settlers by thousands of years. The first record of a commercial fishery is from 1885. 

Today, Dungeness crabs are harvested by indigenous, recreational and commercial fisheries, and is one of the most valuable fisheries on Canada’s Pacific coast, supporting numerous coastal communities. The commercial fishery is well managed to ensure it is sustainable. Restrictions to protect the population include limits on crab size (minimum and maximum size limits), on number of traps and gear type, and zero retention of females.  Crab processed in British Columbia can be found and purchased in Canada but the majority of it is exported to the United States.

Dungeness crabs harvested by pot or trap are listed by most certifications as a good sustainable seafood choice. 

Dungeness crab have not been assessed or listed by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), but have been assessed under the Precautionary Approach Framework by the Department of Fisheries and Oceans (DFO) in Canada as Healthy.

Oceana Canada is working to protect Canada’s oceans for species like the Dungeness crab. Find out more about our campaigns and join us in helping to bring abundance back to the ocean.