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.

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.