Dungeness crab

Dungeness crabs have four pairs of armored legs, two claws, and a wide, hard shell. A Dungeness's legs are shorter compared to other commercial crabs During a molt, the shell will separate where the carapace and abdomen meet. This allows the crab to exit the old shell. In the third year, males molt twice and females molt once. After that, all crabs will molt once a year, with females molting in the spring and males molting in the summer. File:Cancer magister (James Dwight Dana).jpg|The Common Crab of the Pacific Coast. (Male.) Cancer magister, James Dwight Dana. From The Fisheries and Fisheries Industries of the United States File:Large Dungeness Crab.jpg|A large Dungeness crab File:Dungeness crab face closeup.jpg|Close-up of the head: the two eyes sit on eyestalks, with an antennule on either side of the rostrum (center, above the mouth) ==Life cycle ==

eggs during spawning season, Nov 2024 Mature female crabs generally molt in late spring, although exact timing varies with location. ==Habitat and range==

Dungeness are most often found in areas with sandy bottoms Larvae are much more sensitive to such environmental conditions as salinity and require temperatures of between . The typical range of the Dungeness extends from Alaska's Aleutian Islands to Point Conception, near Santa Barbara, California. Occasionally, the crab can be found as far south as Magdalena Bay, Baja California Sur, Mexico. == Fishery ==

The Dungeness fishery was started by San Francisco fishermen in 1848. while Washington is . In Alaska, Washington, Oregon, and California (commercial) fisheries, only male crabs are allowed to be harvested. In Alaska, these closures are due to population decreases likely caused by increased otter predation and environmental shifts. In Washington state, the closures are due to population decreases caused by unknown factors. == Sustainability ==

It is estimated that every season since 1970 the fishery has taken 9-98% of the legal-sized male population with an average of 66% a year. The majority of this catch is caught in the first six weeks of the season. Despite this, the fishery has had a stable mean catch for over thirty years indicating populations are not overfished. This is likely due to the regulations put in place that allow crabs at least one year of sexual maturity before capture. Although 143 crabs are thrown back for every 100 kept, the trapping and subsequent throwing back of non-legal Dungeness does not seem to cause an overabundance of harm to the population. Soft-shelled crabs have been shown to have the highest mortality rates at just 9-25%. Due to catch averages staying consistent, it is assumed populations are healthy, but in reality very little is known about Dungeness crab populations. In California, Alaska, and Washington, research is minimal and information about populations is assumed from catch records. In Canada, two out of seven crabbing areas are examined twice every year. The other areas are studied inconsistently and usually in relation to specific research questions. In Oregon, monitoring programs are in place for mating success, genetic structure, population structure, and discard mortality. The effect of the fishery on other species is variable. The effects on benthic species and bycatch are relatively unknown, although the effects are assumed to be negligible for both. In Alaska and Canada there is no known effect on any other species. In Washington, Oregon, and California, humpback whales are known to be highly affected with a high of 19 humpbacks entangled in crabbing line in 2016. In California, leatherback turtles, orcas, and blue whales have also been known to be impacted. In recent years entanglements of all species have increased; this is attributed to increased reporting and changes in these species' migration due to changes in prey abundance as a result of climate change. Entanglements are lower than they could be due to the timing of the crabbing season: the first six weeks of the crabbing season (when most fishing occurs) happens before the migration of many species. The high seen in 2016 was likely due to a late opening of the season because of toxic algal blooms. Ghost fishing from lost equipment is a problem in the industry, the scale of which is generally unknown. It is estimated that 10-20% of gear is lost each year with 7.5-32.5% of that ghost fishing. Ghost fishing can entangle marine mammals, cause crab death, and harm the ecosystem. Additionally, lost gear may ghost fish in places far from their original spots due to currents and tides; buoys from lost pots in Oregon were recovered four years later in the Hawaiian islands. Overall, Seafood Watch has given the Dungeness crab a sustainable seafood rating of "Good Alternative" meaning they are okay to buy but be sure to be aware of potential concerns. ==Culinary use==

The Dungeness crab is considered a delicacy in the United States and Canada. Long before the area was settled by Europeans, Indigenous peoples throughout the crustacean's range had the crab as a traditional part of their diet and harvested them every year at low tide. The flesh has what is considered to be a delicate flavor and slightly sweet taste. Today they are an integral part of the cuisines of California, British Columbia, and the Pacific Northwest and traditionally feature in dishes like crab Louie or cioppino. About one-quarter of the crab's weight is meat. Dungeness crabs can typically be purchased either live or cooked. A humane way to kill a live crab is to: 1) stun the crab by submerging it in ice water for several minutes, 2) flip the crab onto its back, and 3) drive the tip of a small pick about an inch below the center of its mouth. However, many cook live crabs by simply dropping them into boiling salt water. The crab then is allowed to cook for 15 minutes, after which time the crabs are removed and placed into cold water to cool and then cleaned. Cleaning the crab consists of removing the shell, scooping out the gills and intestines, and separating the legs and claws from the body. When removing the shell there will be a yellow substance, called crab fat or crab mustard (which is not fat, but actually the hepatopancreas) and is used in many dishes. Another method of preparing crab is called half-backing. Half-backing is done by flipping the crab upside down and chopping it in half (from head to "tail"), after which the guts and gills can be scooped or hosed out. Many consider half-backing to be superior to cooking the entire crab, because the meat is not contaminated by the flavor or toxins of the guts. Half-backed crabs boil faster or can be quickly steamed instead of boiled. Some common tools for removing crab meat from the shell are a crab cracker and a shrimp fork. == Threats ==

In some areas adult Dungeness crabs can be found in or near estuaries. The hyposaline conditions of the estuaries are lethal to some of the crab's symbionts, such as Carcinonemertes errans which consumes a brooding female's live eggs. Dungeness crabs surveyed in Coos Bay were less likely to be infected by C. errans and have fewer worms present on their carapace when inhabiting less saline waters farther inland. Another potential harm related to global warming is red tides. Another threat to the Dungeness crab is an invasive species called the European green crab (Carcinus maenas..) The green crab outcompetes the Dungeness crab for food and habitat. ==Celebrations of the Dungeness crab==

In 2009, after lobbying from school children at Sunset Primary School in West Linn, Oregon, and citing its importance to the Oregon economy, the Oregon Legislative Assembly designated the Dungeness crab as the state crustacean of Oregon. In 2024, California governor Gavin Newsom signed legislation designating the Dungeness crab as California's official state crustacean. The 2022-23 crab season brought revenue of about $54.4 million to the California economy. The annual Dungeness Crab Festival is held in Port Angeles, Washington, each October. ==References==