Crabs

There are dozens of species of crabs living in the Chesapeake Bay, with the Blue Crab having the most notoriety because its economic importance as seafood. Most of the other varieties are relatively small in comparison, so they are not sought after as food.

Another species of note is the horseshoe crab, a primitive arthropod with a long spiked tail; it is not a true crab, having more in common with the terrestrial spiders or scorpions.

(courtesy photo)

There are also a number of species of Fiddler Crabs, smallish crabs that measure 1.5 to 2 inches across their “carapace” or shell. Fiddler crabs typically have one claw that is much larger than the other. These crabs can live in deep water, marshes, or burrow into sandy areas in shallow water.

Another very small crab also found in sandy areas is the Mole or Sand crab.

The Black Fingered Mud crab is a small crab found around mud flats, pilings, or oyster reefs. This crab feeds on young oysters and is a major predator of oysters.

The Hermit crab is a small crab that does not develop its own shell; instead this crab will use discarded shells from snails, periwinkles, or oysters.

Some species of crabs have immigrated to the Bay from foreign lands, stowing away in foreign vessels. An example of this is the European Green crab, an invasive species that is native to the North Atlantic and Baltic Sea in Europe.

Other “swimming” crabs that are more common in the Atlantic Ocean or Gulf of Mexico that might find their way into the Bay include the Calico or Lady Crab, Speckled crab, and Rock Crab. These crabs generally grow large enough to eat and are part of seafood fare in areas where they are more common.

A fairly rare individual is the porcelain crab, an arthropod which is actually in the lobster family and lives in deeper waters in the Atlantic Ocean, sometimes making its way into the Bay.

Nature Notes for 7/4/2010