NPS/Breault Ghost crabs, Ocypode quadrata, never miss a day at the beach. Keen eyed visitors to Gulf Islands beaches will delight to watch these quick crustaceans dart in and out of the many crab holes near the water’s edge. Ghost crabs are the fastest land crabs in the world! The pale white color gives the ghost crab its name and makes it rather difficult to spot on Gulf Islands’ sugar white sand beaches. Six yellowish legs support its pale square shaped body. These mesopredators have stalked eyes and have one claw that is larger than the other. You can identify ghost crabs by the clues they leave behind in the sand. Their tracks resemble rows of widely spaced commas. If you follow these tracks, they will likely lead you to the second clue. Holes in the sand mark the entrances to ghost crab burrows. Depending on the size of the crab, these holes range from the size of your finger to the size of a tennis ball.
As scavengers, ghost crabs help maintain the appearance of the beach. They have a diverse diet including coquina clams, mole crabs, and the eggs and young of sea turtles and shorebirds. Ghost crabs dig burrows to escape predators and the weather. They prefer to burrow close to the swash zone in moist sand but will move to burrows behind the dunes in the winter. Ghost crabs are opportunistic and will move their burrows to be close to food. Look closely next time you see a piece of driftwood, a dead turtle, or fish on the beach and will notice the ghost crab burrows seem to surround it.
Ghost crabs are an important indicator species of beach health. Their biggest threats are anthropogenic impacts. The more people use a beach, the greater the impact on the species. Population, size, distribution, and behavior are all affected by human activity. A beach with lots of ghost crab holes is a sign of a healthy beach.
Leave only your footprints when you visit the beach. To help these important creatures survive you can volunteer for beach cleanup efforts. Crabs and other wildlife often cross the road when moving about the island. Pay close attention to the road when driving through the park. Be sure to observe posted speed limits and leave plenty of space between you and the vehicle in front of you.
Griffen, Blaine D. and Gul, Mustafa R. Impacts of Human Disturbance on Ghost Crab Burrow Morphology and Distribution on Sandy Shores. 2018. https://doi.org/10.1371/journal.pone.0209977
Izzo, Lisa and Kothari, Nikhita. Ocypode quadrata Atlantic Ghost Crab. https://animaldiversity.org/accounts/Ocypode_quadrata/#predation Witherington, Blair and Dawn. Florida’s Living Beaches: A Guide for the Curious Beachcomber. Sarasota, Florida: Pineapple Press, Inc., 2007. |
Last updated: April 17, 2020