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Dungeness Crab

The Dungeness crab lacks the size and mystique of the legendary King crab, but savvy Alaskans appreciate the dungie for its flavor and the fact that it's available for harvest nearly year round.

The Dungeness crab is unique to the West coast of the United States. It is named after a small fishing community on the Olympic Peninsula of Washington. It can be found from Unalaska Island south to Magdalena Bay, Mexico. Dungeness crabs have been harvested commercially along the Pacific Coast since the late 1800's, and were first commercially canned in Alaska at Seldovia in 1920.

At 4 to 5 years of age, a Dungeness crab can be over 6 1/2 inches in shell width and weigh between 2 and 3 pounds. A large male Dungeness crab can exceed 10 inches in shell width. The estimated life span of this crab is between 8 and 13 years. Dungeness crabs are carnivores, and their diet can include shrimp, mussels, small crabs, clams, and worms.

Male crabs are active breeders at an age of three to four years, and will mate with several females. Each female produces up to 2.5 million eggs. Fertilization of the eggs does not occur at the time of mating. The eggs are fertilized when the female extrudes them under her abdomen where they are carried for several months until hatching. The eggs hatch into free-swimming larvae in the spring. Larval development takes from 4 months to as long as a year in Alaska.

Crabs grow by shedding their old shell, a process called molting. During their first two years, crabs molt several times. At a size of about 4", or by the third year of life, molting becomes less frequent, occurring only once each year. Just after molting, crabs are very watery and soft and their shell is easily punctured, so they dig into the sand and stay there for several days while their shell hardens.

Dungeness crabs are widely distributed and prefer a sandy or muddy bottom in salt water. However, they are tolerant of salinity changes and can be found in estuaries. They are generally found in waters shallower than 15 fathoms, but they have been found in depths down to 100 fathoms. Observant beachcombers often find Dungeness crabs that have been stranded by minus tides.

Throughout Alaska, only hard-shell male Dungeness crabs over 6 1/2 inches in shell width may be harvested. This size limit and protection of females ensures a sustainable harvest of this tasty and nutritious seafood.

For more information about Dungeness crab, view the Alaska Department of Fish and Game Wildlife Notebook Series.