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Conference Proceeding

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Project Limulus is a long-term study of the population dynamics of the horseshoe crab population in Long Island Sound (LIS). We have tagged over 20,000 spawning adults from >20 beaches ranging from Greenwich to Stonington, CT since 1997. Cumulative recapture rates have reached 9%. On average 90% of the crabs are recaptured within a few miles of their original tag site within the first season. Between seasons, on average, 45% of crabs are recaptured within the same locality of where they were tagged. Of all recaptures, 99% of recaptured individuals are found within LIS. This past year we expanded the study into RI, NY, and MA collaborating with many groups for a regional horseshoe crab census. Preliminary findings reveal low spawning numbers compared to Delaware Bay across the region.


Originally published:

Beekey, Mark, Mattei, Jennfier. "Project Limulus: What Long-Term Mark/Recapture Studies Reveal About Horseshow Crab Population Dynamics in Long Island Sound." 9th Biennial Long Island Sound Research Conference Proceedings October 30-31 2008. Groton, CT: Long Island Sound Research Conference.



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