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Don’t Throw Back that Horseshoe

He’s keeping the species alive

It’s a dark and stormy night, the moon is shaded by clouds. The only light streams from our headlamps and the revolving beam of a nearby lighthouse. The rain is pelting sideways, and the water is above our ankles. Tired and cold but hopeful, our trio trudges down a Calvert County beach at 3am, scanning the turbulent water for a prehistoric monster.
    Suddenly in the surf, someone spots a dark silhouette, like a rock … we draw closer, anxious with excitement. It is indeed what we’ve been searching for: a horseshoe crab. Park ranger Chelcey Nordstrom removes the sand around the base of the male, revealing a second larger female crab buried beneath.
    “Horseshoe crabs on shore should be left alone unless they need help being flipped back over. This is true especially when they are stacked on top of each other, which can sometimes be hard to see.”
    A species more than 300 million years old, the Atlantic horseshoe crab, Limulus polyphemus, seeks out the beaches of Delaware Bay and Chesapeake Bay to mate, lay their eggs and raise young in these shallow and protected waters. Horseshoe crabs can live 20 years or longer and can travel up and down the east coast. But the species is in trouble, due in part to predation and overharvesting. They are also used actively in medical testing because of their copper-based blood. However, little is known as to why they choose our beaches, where or why they travel or many other habits.
    Data gathered from our Anne Arundel Community College’s science class findings will be used in an ongoing study by college professor Paul Bushman to shed light on these unanswered questions. Last year’s student study group attached radio tags to crabs found, and hopefully collection of those same tagged crabs this year will reveal where they went, how far they traveled, how long they stayed in each location and other curiosities about these ancient creatures. Armed with this new information, advances can be made to further preserve this unique species.