Virginia Institute of Marine Science
Center for Coastal Resources Management (CCRM)
Salt marshes and their inhabitants are being displaced by climate change and human development along the coastline. One inhabitant, the ribbed mussel (Geukensia demissa), forms a mutualistic relationship with smooth cordgrass, Sporobolus alterniflorus, along the US Atlantic Coast. Ribbed mussels stabilize the marsh, remove particulate matter from the water column, and promote denitrification, thereby improving local water quality. To quantify the potential effects of SLR on ribbed mussel abundance and resulting impacts on water quality functions, we compared the current and projected future (2050) spatial distributions of ribbed mussels in Chesapeake Bay assuming an intermediate SLR for the region. We found that ribbed mussel abundance was reduced by more than half due to a combination of drowning marshes, coastal squeeze, and a shift from higher to lower quality habitat. Mussel losses were greatest along the mainstem of the Chesapeake Bay, with modest gains in the headwaters. Our results highlight the importance of permeable land cover (including living shorelines) in the future tidal extent to promote marsh transgression for future mussel populations. The projected mussel abundance reductions will result in a > 50% reduction in mussel-mediated filtration and nitrogen processing, ultimately reducing the resilience of marshes in the system.
Ribbed mussel, Sporobolus alterniflorus, Ecosystem services, Chesapeake Bay, Spatial
Accepted manuscript version.
Isdell, Robert E.; Bilkovic, Donna M.; and Hershner, Carlton, Large Projected Population Loss of a Salt Marsh Bivalve (Geukensia demissa) from Sea Level Rise (2020). Wetlands.
Available for download on Wednesday, November 03, 2021