Fate of Freshwater Mussels Transplanted to Formerly Polluted Reaches of the Clinch and North Fork Holston Rivers, Virginia

ABSTRACT

Adult freshwater mussels (Unionidae) were translocated to reaches of the Clinch and North Fork Holston rivers in southwestern Virginia, where mussels had previously been eliminated by water pollution. A total of 3,872 adult mussels of seven species were translocated and monitored for up to four years. Annual declines of some species were roughly 10%, whereas other species appeared to decline much more rapidly. Losses were attributed largely to the high natural mortality of the older mussels that were translocated, as little active or passive movement of mussels from the sites was detected. Some mortality of mussels moved to the Clinch River may have been related to continuing perturbations in water quality. Site selection and the use of both young and adult cohorts appear to be key factors in the successful translocation of mussels.