As a predator, blue crabs are fierce hunters of marine worms, snails, small fishes, other crabs and just about anything small enough for them to subdue with their powerful claws; the blue crab’s busi-ness ends when it comes to interacting with others, including prey, enemies, and careless fingers or hapless toes. As scavengers, blue crabs prowl marshes and other inshore waters in search of dead fish resting on the seafloor or a piece of chicken neck tied to a crabber’s string. Blue crabs, as with many animals, are opportunistic feeders; they will catch and eat anything that offers nourishment, from marine algae to animal tissue, fresh or rank. Looking across a saltmarsh creek, one may see a frenzied school of small fish break the water’s surface in a panicky attempt to evade an unseen threat from below. While it’s easy to fantasize that a big drum or flounder is flushing the frenzied schools of silversides, mullet or menhaden, the more likely culprit spook-ing the fish is a different beautiful swim-mer — the blue crab. Blue crabs will often hide in loose sand or mud, just deep enough to conceal their outline, but shallow enough to strike at passing prey, using their bigger clutch-ing claws to subdue a meal. Nothing within reach is safe from a crab, especially anything smaller than the crab itself, including charming little fiddler crabs in marshes and other tidal areas. A quick look at the blue crab will reveal its specialized legs; the front-most pair adapted for food gathering, with each of these legs tipped with a pinching claw called a pincer or chela. Behind this front pair are three pairs of point-tipped walk-ing legs and the rearmost legs end with a flatted swimming paddle, indicative that the blue crab is a member of the swimming-crab family. Looking at its underside, one can see its flattened tail, or telson, tucked tightly to its abdomen. The male’s telson is narrow, whereas the female’s is triangular when immature, eventually becoming semi-circular. The female telson serves as an apron for the mature blue crab to carry her ripening eggs — upwards of one to two million per crab. Crab larvae hatched from these eggs are called zoea, each smaller than a grain of sand, and sporting sharp spines that can prick tender skin when the tiny creatures get caught inside a bathing suit. Close observation of a blue crab’s pair of claws will reveal one larger than the other; the larger one employed as a 36 august 2014 WBM Blue crabs will often hide in loose sand or mud, just deep enough to conceal their outline, but shallow enough to strike at passing prey, using their bigger clutch-ing claws to subdue a meal.
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