In-situ feasibility study of freshwater mussel reintroduction: survival and growth of the Slippershell (Alasmidonta viridis) in the Upper Oconaluftee River, NC (Swain Co.)

North American freshwater mussels are an imperiled group of organisms, with 29 of the 102 species in the Tennessee River basin listed as federally endangered or threatened, and another 11 believed to be extinct (Fraley 2002). The Slippershell mussel (Alasmidonta viridis) has a widespread distribution but is protected as an endangered species in North Carolina. I monitored survival and growth of juvenile A. viridis in enclosures placed in the upper Oconaluftee River near Cherokee, NC to determine if the species may be successfully reintroduced on Eastern Band of Cherokee Indians tribal land. I also compared two enclosure designs: concrete enclosures modified from a design originally described by Chris Barnhart, and mesh enclosures that allow access to the substrate, modified from a design used by Rachael Hoch. Timed snorkel surveys were also conducted to confirm the presence of the appropriate fish host, Mottled Sculpin (Cottus bairdii). Between March and September of 2018, Alasmidonta viridis experienced significant mortality at all sites and in both enclosure designs. There was also no evidence of growth among survivors. Alasmidonta viridis may be sensitive to handling, as the cohort of mussels used in this study experienced increased mortality after tagging in captivity and prior to the experiment