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Blue Crab Information
Blue crabs are found from Nova Scotia south to northern Argentina. They are an important link in the food chain, feeding on fish, aquatic vegetation, mollusks, crustaceans, and annelids while they serve as prey to mammals, birds, and fishes.
Highly prized by seafood lovers, blue crabs are usually steamed or boiled, either whole or with the top shells removed. In the Mid-Atlantic region they are traditionally seasoned with a spicy crab seasoning in the steamer and again when served.
Maryland, Virginia and North Carolina are among the top blue crab harvesting states of the USA.
The Atlantic blue crab (Callinectes sapidus) is a member of the Brachyura - an order of crustaceans having a reduced abdomen, or "apron," folded against the ventral surface (or belly) of the animal. The blue crab is found in inshore environments from Nova Scotia to Argentina.
Male crabs can be distinguished from females by the shape of the abdomen. The male has a T-shaped abdomen that is held tightly against the body until maturity when it becomes somewhat free. The immature female has a triangle-shaped abdomen that is tightly sealed against the body. The mature female's abdomen becomes rounded and can be easily pulled away from the body after the final molt.
Adult female blue crabs can produce three broods per year, releasing approximately three million new crabs per brood.
Breeding female blue crabs carry fertilized eggs under their abdomen. The mass of eggs resemble a sponge, hence the term "sponge" crab. It takes about two weeks for the eggs to "ripen" and be released into the water to hatch. It is illegal in many states to possess sponge crabs.
Large males, often called Jimmy crabs, usually have brilliant blue claws and legs. The mature females or "sooks" can be distinguished by the bright orange tips on their claws. Males typically grow larger than females, sometimes reaching 7 or 8 inches in point-to-point width. Some males have been reported to grow to about 10 inches.
Blue crabs eat a variety of foods, including fishes, oysters, clams, snails, shrimp, worms and other crabs. They sometimes burrow into the bottom with only their eye stalks visible, lying in wait for prey. Crabs are opportunistic feeders, eating whatever is available.
Most of the crabs caught commercially are taken in crab traps. A trap is a rectangular device made of chicken wire about 2 feet wide. It has inverted funnels in the sides, through which the crab can enter, but will have difficulty leaving. The trap is baited with freshly dead fish. It is said that crabs can detect and locate the source of fish oil from a distance. In some areas, crabs are also caught in trawls and by trotlines.
How to Steam or Boil Blue Crabs
Blue crabs are usually steamed or boiled, either whole or with the top shells removed. In the Mid-Atlantic region they are traditionally seasoned with a spicy crab seasoning in the steamer and again when served.
In Southern Atlantic and Gulf Coast cuisine, crabs are sometimes boiled rather than steamed and seasoned with a "crab boil" seasoning.
A lesser known method of cooking crabs is to fry the cleaned bodies in oil, sometimes being dipped in egg and breaded before frying.
Blue crabs are picked and eaten right after cooking, or may be cooled and the meat removed later, either to eat on the spot or saved for use in crabcakes and other crabmeat recipes.
During cooking, it is critical that blue crab meat reach an internal temperature of 70 degrees C (158 degrees F) for at least one minute to insure the destruction of the bacteria Vibrio cholerae, which may contaminate blue crabs.
For safety, steam the crabs for 25-30 minutes or boil them for approximately 15 minutes. Either method is effective.
Blue Crab Links
Articles and resources on how to buy, clean, cook and enjoy blue crabs and other shellfish.
Creamy Blue Crab Dip
Creamy Blue Crab Dip
1 (8 oz.) package of cream cheese, room temp.
1 tsp. Worcestershire sauce
2 Tbsp. minced green onions
salt and pepper to taste
8 oz. cooked blue crab meat
In a small bowl, combine cream cheese with Worcestershire sauce and green onions. Beat until creamy, adding milk to achieve desire consistency. Season to taste with salt and pepper. Gently fold in crab meat and transfer mixture to an ovenproof casserole dish. Bake in preheated 325 degree oven for 15-18 minutes or until hot. Serve with crackers or French bread.