We have always talked about “blue bloods” here in Charleston, referring to distinguished, long-time families who have kept names and traditions intact. Yet, the truest blue-blood found in Charleston these days are the Horseshoe Crabs floating up on area beaches and sand flats.
The Horsheshoe crab is not actually a crab or crustacean, but a sea-dwelling anomaly closer related to spiders. Its circulatory system is laden with copper that turns the crab’s blood blue, and this blue blood is very valuable to modern science for its ability to bind to harmful bacteria and help prevent toxic reactions in various medicine.
The striking feature of the Horseshoe crab is its helmet-like carapace, from which extends a fierce-looking spiked tail called the telson. What looks
dangerous is actually very harmless, as the telson is simply used by the crab for leverage when flipping over. Underneath, the Horseshoe crab has five pairs of legs, used for eating, propulsion and, in the case of the males, for grabbing and holding females during summer mating.
Although the Horseshoe crab has ten optical appendages, it really can’t see very well, as I have found personally. I joined some biologists some years back who were collecting the blue blood from Horseshoe crabs who are easiest to find during mating season when they herd by the thousands into shallow water. In the near-sighted males’ frenzy to connect, they will latch on to anything, including human feet like mine, and I spent most of the adventure pushing the herd of helmets away.