Horseshoe Crab Survey: Calvert County and Beyond
Help us document the distribution and abundance of horseshoe crabs during their annual mating season along the shores of the Chesapeake Bay in Calvert County and beyond!
Sign up for the Calvert Stewards Opportunity
Use iNaturalist to photograph and map your observations in a few easy steps.
You can also help verify other people's observations to improve our data quality, come to a scheduled horseshoe crab survey, or even hold your own event. You can also explore on your own.
Spread the word—it's a big area! The area includes the entire Chesapeake Bay Shoreline in Maryland, Virginia and Delaware. We are really interested in Calvert County sightings, but any observations along the Chesapeake are important.
There are many questions about this “living fossils.”
How You can Help
Become a Calvert Steward and learn how to:
Atlantic Horseshoe Crab
Horseshoe Crabs have been nick named “living fossils:”
Their scientific name, Limulus polyphemus, is from the Greek one-eyed monster, are one of 4 species worldwide.
They occur along east coast from Maine to Florida and Yucatan Peninsula.
Horseshoe crabs today don’t look a whole lot different from the fossils of their ancestors – hence the nickname – living fossils. They have been relatively unchanged for about 350 million years
Did You Know...