Blue crabs almost always walk sideways clearing a path with their sharp lateral spines. The blue crab's
most prominent features are the large and powerful claws which are used for food gathering, defense, digging and
sexual displays. Blue Crabs found from Nova Scotia to Uruguay, however they are most
common from Massachusetts to Texas. To complete its life cycle the blue crab requires both brackish, inshore waters,
and the high salinity of ocean waters . The blue crab's scientific name, Callinectes sapidus, translates to "savory
beautiful swimmer." Swimming is accomplished using the oar-like fifth pair of legs. Walking is accomplished
with the middle three pair of thin walking legs.Blue crabs almost always walk sideways clearing a path with their sharp lateral spines. The blue crab's
most prominent features are the large and powerful claws which are used for food gathering, defense, digging and
sexual displays.
Male crabs can be distinguished from females by the shape of the abdomen and the coloration of their claws. The male (left in the picture at right) has a T-shaped abdomen, often compared to the Washington monument, and usually have brilliant blue claws and legs. The immature female has a triangle-shaped abdomen. The mature female's abdomen (right in the picture at right) becomes rounded, and has been compared to the Capitol dome in Washington DC. Females can also be distinguished by the bright orange tips on their claws.
For more information see the following links:
Virginia Institute of Marine Science
EPA
The Blue Crab Network
South Carolina
Department of Natural Resources