Maria Mitchell Association: Celebrate the Horseshoe Crab

To: Bluedot Living

From: The Maria Mitchell Association

Subject: Celebrate the Horseshoe Crab

This year, the Maria Mitchell Association (MMA) encourages members of the community to celebrate the Atlantic horseshoe crab. Relics of the past, horseshoe crabs have roamed our oceans relatively unchanged for 450 million years. These “crabs” (who aren’t related to true crabs like blue crabs) have seen it all. They’ve been a food source, treated as a nuisance species, used as bait, and heralded as ecological staples, especially on the East Coast. The Atlantic horseshoe crab (Limulus polyphemus) is also important to the biomedical industry. Components from their blue blood are used to test medical equipment for sterility.

The MMA is proud to work with these crucial animals. MMA surveys Monomoy Beach as part of a program hosted by the Massachusetts Department of Marine Fisheries (DMF). Around the new and full moons of May and June at high tides, MMA staff and volunteers counted the horseshoe crabs swarming the beach to mate. The data is sent to DMF to assess the status of the horseshoe crab population. Most of the state’s horseshoe crab harvest happens in Nantucket Sound, so our work on Monomoy Beach will continue to be vital in years to come.

In recent years, MMA’s Hinchman House Natural Science Museum started its “Horseshoe Crab Head-Start Program.” Horseshoe crab eggs are gathered and hatched at the museum, where the public can watch their growth and development. One year later, they are released back to their original location. The hope is to provide extra care to hatchlings who face high mortality in the wild. Other young horseshoe crabs are also kept at the museum for several years before being released.

MMA will be hosting a horseshoe crab celebration this June to honor the ancient creatures. On June 22, MMA will have an outdoor celebration, including activities, games, and the chance to get up close and personal with Atlantic horseshoe crabs! Later that evening, MMA staff will lead a beach walk to count the horseshoe crabs and learn about the astral events that the horseshoe crabs are sensitive to.

We encourage Nantucketers to explore the science and behaviors of these amazing animals. 

A few tips in caring for horseshoe crabs 

• When you see a horseshoe crab on the beach, avoid picking it up by its tail. Often mistaken for stingers, their tails help them move in the water, and if pulled too hard, they can be damaged. 
• If you find a horseshoe crab flipped upside down, you can do it a favor by gently flipping it back over so it can make its way back out into the water. 
• If you’d like to get up close and personal with these amazing animals, feel free to visit the Maria Mitchell Association Aquarium or Natural Science Museum, where staff will be happy to tell you all about the Atlantic horseshoe crab! 
• If you have questions about horseshoe crabs on Nantucket, feel free to email our aquarium director at [email protected]