Mud or Stone? Make sure you have the right crab!

mud crab FWC

A mud crab in an oyster bed. (Photo credit: FWC)

Anglers in southwest Florida are fortunate they have several options to chose from when fishing with live bait; particularly crabs. Besides using blue and fiddler crabs to catch popular species such as red drum, sheepshead, and pompano, many anglers also use what is known as mud crabs. As their name implies mud crabs are often found in muddy environments particularly around oyster beds, shell rubble, rocks, pilings, mangrove prop roots, and other structures. While there are several species of mud crabs, they typically have brownish to black-colored carapaces (or shells) and the fingers (or tips) of their thick, unequal-sized claws are also dark in color. The interior portion of their claws, however, tend to be pale in color.

Mud crabs belong to the family Xanthidae, which also includes the more familiar Florida stone crab (Menippe mercenaria). Like many mud crabs, the fingers of a stone crab’s claws are also dark in color. Depending on their size, a stone crab’s carapace can vary from black/dark purple to tan in color, which can look similar to the body of a mud crab.

Unlike mud crabs, however which are not a regulated species, stone crabs are highly regulated. In fact, only a stone crab’s claws can be harvested and the crab must be returned to the water alive. Claws must be at least 2 3/4 inches in length from the bottom tip of their claw to the bend in their claw, and claws may only be harvested between October and May.

Because mud crabs and small stone crabs often inhabit the same environments and look similar, anglers should be cautious to ensure they are harvesting the correct crab. Being in possession of a juvenile stone crab can actually result in a double fine; one for being in possession of  undersized claws and two for being in possession of the whole crab. While these offenses are considered misdemeanors, they can result in hundreds of dollars in court fees and time in jail per offense.

One of the simplest methods of distinguishing between stone and mud crabs is to look at the crabs’ legs. Stone crabs will have distinctive bands on their legs, whether it is a juvenile or an adult. Mud crabs do not have the bands at all. (see illustrations below).


juv stone crabs.jpg small stone crab.jpg

mud crabs.jpg

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