About the Project Horseshoe crabs (Limulus polyphemus) and diamondback terrapins (Malaclemys terrapin) areimportant species that utilize the intertidal and subtidal habitats within the Peconic Estuary. Both of these species are […]
Horseshoe crabs (Limulus polyphemus) and diamondback terrapins (Malaclemys terrapin) are
important species that utilize the intertidal and subtidal habitats within the Peconic Estuary. Both of these species are affected by similar ecosystem stressors and are particularly vulnerable to the loss of these habitats, which are essential for their deposition of eggs after reproducing. Shoreline hardening, sea level rise, and dredging all present ever-increasing challenges to species reliant on adequate access to beach habitat within the intertidal range or at higher elevations.
Both horseshoe crab and diamondback terrapin abundances within the Peconic Estuary are at low levels. In the latest review of horseshoe crab population status, the Atlantic States Marine Fisheries Commission (ASMFC) recently listed the status of horseshoe crabs in New York State as “poor,” and data generated by the NYSDEC’s annual juvenile finfish trawl survey has shown a dramatic decline in abundance of horseshoe crabs in the Peconic Estuary from 1987 to 2012. Additionally, CCE and NYSDEC’s annual horseshoe crab survey indices demonstrates that spawning levels in the Peconic Estuary are the lowest
of all estuaries in New York State.
Both horseshoe crabs and diamondback terrapins are currently listed as “vulnerable” on the IUCN Red List of Threatened Species. Diamondback terrapins are also considered a species of “special concern” in New York State. Additionally, there has been a steady decline in salt marsh habitats in New York State, furthering the decline of local terrapin populations.
More information on these two species are needed to help guide conservation policy for intertidal and beach habitats with respect to shoreline hardening, sea level rise, and other factors. Modern telemetry methodologies may be a useful approach to provide critical data about habitat use by both species, and such technology may have potential to extend to other species of concern in the future.
This mini grant was awarded to CCE proposed a pilot-scale test of satellite telemetry technology to advance the monitoring of
diamondback terrapins and horseshoe crabs within the Peconic Estuary. In just the last few years satellite tags have improved greatly with respect to their size, battery life, spatial accuracy and the inclusion of additional environmental sensors (e.g. temperature, depth, etc.) that are recorded simultaneously while tracking animals. Hence, these modern tags may now be
suitable to apply to aquatic species such as horseshoe crab and diamondback terrapins.
CCE staff collected five adult female horseshoe crabs and four adult female diamondback terrapins by hand from spawning/nesting sites within the Peconic Estuary between the months of May and August. Each animal’s carapace were tagged with satellite tags, sending out a GPS pin every time the tag comes into contact with the air. The data can be used to help map habitat use as well as provide a greater understanding of behavioral metrics. With this information, PEP and partnering organizations will be better equipped to recognize monitoring gaps and strengthen the development of a detailed estuary-wide habitat restoration and protection strategy. Such a strategy will help PEP map out areas for restoration and protection based on their importance to key estuarine species or risk of future inundation as a result of sea level rise and increased shoreline hardening.
Contact Matt Sclafani for more information on this project.
