Projected Range Shift of the Atlantic Surfclam, Spisula solidissima, and the Ocean Quahog, Arctica islandica, Under Climate-Induced Benthic Warming: Forecasting Fishery Influence in the Mid-Atlantic Bight Throughout the 21st Century

• Main Author: Spencer, Molly Mae
• Format: Text
• Language: unknown
• Published: The Aquila Digital Community 2024
• Subjects: Atlantic surfclam; Ocean quahog; Mid-Atlantic Bight; Fishery; Climate change; Ecotone; Marine Biology; Oceanography and Atmospheric Sciences and Meteorology; Arctica islandica
• Online Access: https://aquila.usm.edu/masters_theses/1066; https://aquila.usm.edu/context/masters_theses/article/2124/viewcontent/auto_convert.pdf

The Atlantic surfclam, Spisula solidissima, and ocean quahog, Arctica islandica, are biomass dominant bivalve species on the eastern North American continental shelf, both supporting lucrative commercial fisheries in the Mid-Atlantic with a combined value of $53.6 million in ex-vessel revenue per year. Rapid climate change is expected to modify the geographic range of these bivalve populations across the Mid-Atlantic Bight (MAB), suggesting transformative consequences for the surfclam fishery. This study forecasted future distributions of the two species from years 2016 – 2095, based on projected bottom water temperatures and a temperature-dependent population dynamics model, to project subsequent fishery-based indicators using a Spatially Explicit, agent-based Fisheries and Economics Simulator (SEFES). Simulations showed a positive trend in Atlantic surfclam biomass throughout the next three-quarters of the century as the clam’s range continues to shift offshore and northward into habitat previously occupied by the ocean quahog, restricting ocean quahog habitat to offshore Long Island by 2095. Regional surfclam populations expand into deeper waters off New Jersey, Long Island, and southern New England starting in the early 2050s, whereas Georges Bank and Delmarva populations begin to gradually decline. A general decrease in fishing mortality is projected, with a simultaneous increase in catch and LPUE (landings per unit effort), signaling future potential growth in the surfclam fishery. These results can inform industries dependent on this resource, and other competing coastal users, by providing a basis for the development of anticipatory management for the socio-ecological and economic impacts that may result from future changes in range distribution.