Despite their name , blue crabs are typically more of a gray to dull blue-green in color . Only their claws are truly blue , with the claws of mature females tipped in a bright orange-red . There‚Äôs another easy way to distinguish between a male and female blue crab : Myrtle beach locals know to look for the “apron” . Males have a T-shaped abdomen , while females have a triangular abdomens that becomes rounder as they age . As crabs grow , they shed their shells , a process called molting . The crab takes in water to expand and break out of its old shell . A new, soft shell is revealed underneath and quickly hardens . These crustaceans are among the most heavily harvested creatures on the planet . They feed on almost everything they can get hold of ,…