Tuesday, October 21, 2008

Ghost Crabs

Residents of sandy beaches, ghost crabs live in burrows that they dig along the seaward edge of the dune line. These burrows are up to four feet deep and provide a cool, wet retreat where the crabs escape predators and keep their gills moist and functional. Though they are most active from dusk to dawn, scouring the beach for food and bathing their gills in the surf, ghost crabs are often encountered during the day and are easily identified by their pale color and prominent, dark eyes; the latter, which sit atop stalks, give these crustaceans a comical, alien appearance.

Ghost crabs were abundant on Longboat Key this past week; both immature and adult crabs scurried across the beach throughout the day, diving into their burrows or out into the water as walkers approached. They feed on a wide variety of plant and animal life, including seaweed, carrion, sand fleas, mole crabs, stranded fish and sea turtle hatchlings; their taste for the latter has led to their persecution in some turtle recovery areas.

Named for their pale coloration, nocturnal activity and rapid disappearance into burrows, ghost crabs are a food source for night herons, great blue herons, raccoons and gulls. They are also threatened by beach erosion and, ironically, often succumb to artificial beach restoration efforts. For now, their welfare seems assured on Longboat Key!