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The Blue Crab belongs to the crustacean order of Decapoda, and consists of several species which are prized as delicacies worldwide. This crab lives along the eastern coasts of North and South America. It prefers waters known as "brackish," a mixture of fresh and salt water, sea grasses and weeds.

Like most large crustaceans, the blue crab has a hard shell. The shell ranges in color from olive, brown or red to varying shades of blue. The shell of this crab is made of chitin and hardened with calcium. The blue crab's pinchers or "chelae" are large and very unequal in size. The crab has both pinchers and legs and is one of the few crustaceans who are capable of swimming.

The eyes of the blue crab rest on short stalks, and are like those of insects, allowing the crab to see even the smallest movement in almost any direction. The blue crab has five pairs of legs, like other crabs. The male carries blue legs and the females are reddish-orange in color. The first pair of legs holds the sharp claws of the Blue crab, which are used to capture and hold food. They can also be used as a protective measure, holding predators in a painful grip. Often times, when threatened, the crab can allow these claws to break or drop off. Through the process of molting, the crab is able to regrow its claws. The Blue crab also has "paddles," which are formed at the tail end of its body. These long, flattened legs enable the crab to swim, a skill not found in many crabs. The Blue crab's other three pair of legs are used solely for walking.

During molting, the hard outer shell of the crab is discarded. A new, softer shell, which has already formed under the old shell, swells and begins to harden in the seawater. Molting begins as a break in the outer shell. Just below the crab's eyes and on either side of its mouth, the shell cracks open, so that the crab is able to back out. Male crabs molt through out their lifetime to accomodate their large bodies. Female crabs molt before breeding or when injured. Young crabs molt almost continiously during their early development.

Mating of the blue crab occurs between June and October. The male crab dances and waves at the female during courtship, using his swimming paddles to attract the female's attention. A mature female blue crab is 1-1/2 years old and prepares for mating by losing her shell or "molting." A few days before shedding her hard shell, the male grasps on to the female and holds her tightly beneath his own shell. A few days later, the female is released to complete the process of molting. Mating occurs once the female has released her old shell. Because the female is extremely vulnerable while growing her new outer coating, the mating male will often protect the female during this time. After several days, as the female's shell hardens, she separates herself from the male, and travels closer to the water's edge, where she burrows in the mud for the winter.

The female crab carries fertilized eggs in her abdomen in an area referred to as the "apron," on the underside of her body. The eggs undergo larval development inside the female. Once summer arrives, eggs are brooded, at which time they then develop into larvae. Of the many eggs that hatch, as few as two may live to reproduce. With an average size of .1 inches, the larvae spend the first days of their lives drifting between plants and plankton. Every three to five days, small crab larvae molts to accommodate their growing body. Young crabs molt many times and eventually, grow to 7 inches in length in about 200 days.

The blue crab are considered scavengers, often feeding on the bodies of dead animals at the bottom of the ocean. It is because of this that the blue crab has survived as a population.

Today, blue crab is considered a delicacy in much of the world. Favored for their soft, sweet meat, blue crab is actively hunted.