Fiddler Crabs

     Fiddler crabs are cute little coastal creatures with an interesting courtship, though they are overlooked by most people because they are small, secretive and camouflaged.  Most species of fiddlers are about one and a half inches across at maturity.  And like all crabs, fiddlers have ten legs, the front two of which are modified into claws or pincers.  They use the other eight legs to walk sideways in search of food and mates.  Their exoskeletons, or shells, are hard, but they periodically shed their shells so they can grow.  The soft shell under the hard one becomes stiffer within several days after the older one is shed.  But fiddlers hide until those new shells do become hard.  Also, if a leg or pincer was lost in the old shell, that leg or pincer will be part of the new one. 
     There are several species of them, each of which survives about two years at most and lives in burrows the crabs dig themselves in the mud of salt marshes and mud beaches and the sand of sandy beaches on the shores of West Africa, the western Atlantic Ocean and the eastern Pacific Ocean.  I have seen colonies of fiddlers around their burrows at several far-flung places, including along the Delaware River at Delaware City, Delaware, on mud flats at Stone Harbor, New Jersey and sandy places along the harbor in Charleston, South Carolina.     
          Males of each kind of fiddler have a front claw that is as big as the rest of its body and certainly much larger than its other pincer, which is used to gather food in the mud or sand the crabs live in.  The rapid action of the small claw moving from the mud or sand to the crab's mouth looks like it is rubbing against the much larger pincer, hence looking like the action of fiddling, which gives the fiddlers their common name. 
     Each male fiddler waves his large claw to attract the attention of females so they will see him and mate with him.  Males also use their larger claws to intimidate or fight rival males to gain possession of nearby females for breeding.  If a male loses the bigger pincer, the smaller one grows larger and a new small one develops where the former big one was. 
     The larger claws of male fiddlers became that way over time by selection by the females.  Each female fiddler, which has two small pincers by he way, chooses a breeding partner by claw size and the way in which he waves it.  The higher the quality of the wave display, the more health and vigor is needed to do it.  Females choose males with the most vigor, which ensures they will help produce healthy offspring. 
     Each female fiddler spawns her eggs in a mass down her burrow for safety for herself and the eggs.  She carries that blob of eggs on her underside for two weeks.  Then she leaves her tunnel to release her eggs into the receding tide where the young float in the current and filter tiny edibles from the water.  Eventually each tiny crab matures and settles again on the land, digging burrows in the sand or mud for protection from predators and growing to maturity.
     Adult fiddlers have several predators that eat them when opportunities arise to do so.  A variety of gulls and herons, plus raccoons and other predatory critters eat fiddler crabs when they catch them out of their sheltering tunnels.
     Fiddler crabs are interesting little creatures.  But one usually has to look for these camouflaged denizens of mud flats and sandy beaches along ocean coastlines to experience them.  Their most outstanding feature is, of course, the males' one very large claw they use for displaying to the females and fighting other males.