Each spring and fall in Cedar Key, as full and new moons drive tides rise to seasonal highs along marsh edges and sandy shorelines, horseshoe crabs emerge from the water to spawn. In doing this, horseshoe crabs are continuing a cycle that has persisted for at least 150 million years. For the past decade, Florida Horseshoe Crab Watch (FHCW) volunteers have been there too! Volunteers document data on nesting events and tag horseshoe crabs for a population study. The goal of the program is to collect large-scale and long-term data on horseshoe crab populations in Florida, filling data gaps for management agencies.

A Foundational Partnership

Florida Horseshoe Crab Watch was founded in Cedar Key in 2016 as a partnership between the UF/IFAS Nature Coast Biological Station, Florida Sea Grant, and the Florida Fish and Wildlife Conservation Commission (FWC). The program relies on citizen science, or data collected by well trained volunteers, and aims to build local stewardship of horseshoe crabs by leveraging volunteer knowledge to educate the beachgoing public. Since its founding in Cedar Key, the program has grown steadily and now supports active monitoring efforts in 20 additional Florida counties. Statewide leadership provided by FWC ensures that each county coordinator has the equipment and logistical support to train and manage their own local cadre of volunteers.

The dedication of the statewide volunteer corps is reflected in the numbers: 1,796 volunteers have contributed 24,149 hours to Florida Horseshoe Crab Watch, completed 4,876 standardized surveys, and educated 12,143 people through outreach. Cedar Key alone accounts for roughly 20% of the total statewide output, with 374 volunteers, 4,908 volunteer hours, 1,089 surveys, and 3,491 educational contacts over the last ten years: an extraordinary contribution from such a small coastal community!

Overcoming Challenges

Over the past ten years, Cedar Key and Florida Horseshoe Crab Watch in general has faced many challenges. For example, the COVID 19 pandemic presented challenges to in person trainings and gear pickups. Program leaders adapted quickly by providing a virtual training option and volunteers worked with local coordinators to come up with survey guidelines to keep sampling safe for everyone. These changes allowed volunteers to collect data at the maximum possible number of sites and time points, even during the pandemic. In Cedar Key specifically, multiple major hurricanes have impacted our shorelines since 2016 – Hermine, Idalia, Debby, and Helene – not to mention numerous other minor storms. These storms amplified the logistical hurdles that already come with working in a dynamic coastal environment and some of our volunteers were impacted personally through flooding or other damage to their homes or property. Nevertheless, FHCW sampling was sustained, albeit sometimes on a reduced basis depending on site access and safety. Sampling was sometimes more difficult and conditions were often far from ideal—but many surveys were still completed, data were still collected, and the long term record was protected because volunteers continued to show up for horseshoe crabs.

A Wave of Impacts

The impact of this work continues well beyond the shoreline. At least ten peer reviewed research articles have been published using FHCW data. Importantly, one early study directly demonstrated the value of citizen science by showing the data collected by FHCW volunteers was high quality and suitable for use in ecological research and management. Since then, additional studies have covered topics such as body size, spawning distribution, epibiont communities, and threats to American horseshoe crabs across Florida. Researchers have examined how environmental drivers such as wind, temperature, and shoreline characteristics influence spawning behavior and carried out climate focused studies evaluating how sea level rise and coastal change may affect present and future spawning habitat. Furthermore, the information collected by citizen scientists is used by management agencies including the Florida Fish and Wildlife Conservation Commission and the Atlantic States Marine Fisheries Commission in population stock assessments, management decisions, and practical solutions to horseshoe crab threats.

This milestone arrives during April, Citizen Science Month, a fitting time to celebrate the people who have made this program possible. What’s more, enthusiasm for Florida Horseshoe Crab Watch remains strong. A recent training workshop in Cedar Key filled quickly and even had a waiting list, proving that even ten years in, community interest continues to grow.

As Florida Horseshoe Crab Watch looks ahead, its foundation remains the same: well-trained volunteers produce high quality, consistent data across large spatial scales and act as local educators and stewards of horseshoe crabs along the way. Ten years later, we in Cedar Key are still watching the tides and still leading the way. This 10-year milestone for FHCW coincides with the 10-year anniversary of the UF/IFAS Nature Coast Biological Station and serves as an example of the enduring and impactful partnerships between UF/IFAS and the Cedar Key community.

Get Involved and Learn More

Want to get involved? Check to see if Florida Horseshoe Crab Watch exists in your area and contact your county coordinator to get started! Find your county coordinator at the bottom of FWC’s Florida Horseshoe Crab Watch page. See below for some selected research if you want to read more about horseshoe crabs in Florida! Have a happy #CitizenScienceMonth!

• Heres, B., Abeels, H., Shea, C. and Crowley-McIntyre, C.E., 2024. Environmental variables driving horseshoe crab spawning behavior in a microtidal lagoon in Florida. PloS one, 19, p.e0302433. https://doi.org/10.1371/journal.pone.0302433
• Barry, S., Abeels, H. and Krueger, S., 2020. The American Horseshoe Crab (Limulus polyphemus): SG190, 10/2020. EDIS. https://ask.ifas.ufl.edu/publication/SG190
• Contrada, D., Crowley-McIntyre, C. and Heres, B., 2025. Potential implications of rising sea level on American Horseshoe Crab (Limulus polyphemus) spawning beaches in two Florida counties. Plos one, 20, p.e0333812. https://doi.org/10.1371/journal.pone.0333812

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