Due to the presence of sensitive species and difficult access, visitation is restricted at Pendleton Island, a collection of three predominately wooded isles in the Clinch River in southwest Virginia. This environment supports the highest concentration of Cumberlandian mollusk species known to exist anywhere in the world. To date, 45 species have been identified, of which eight are federally listed as endangered.
Scott County, in the Clinch River.
Freshwater mussels somewhat resemble saltwater clams and mussels. Most are enclosed between two protective shells and dig and anchor in the substrate with a long, muscular "foot."
Mussels play an important role in the ecology of freshwater ecosystems. They serve as a major food source for wildlife species such as muskrat, raccoon, otter, and mink. Waterfowl and game fish also eat young mussels. Furthermore, mussels filter particulate matter out of the water, serving as biological filters to help clean turbid and polluted waters. Mussels can also be used by scientists as "biological monitors" of past and present environmental conditions in river systems. By filtering material out of the water, mussels accumulate pollutants such as pesticides and heavy metals that generally occur at very low concentrations. Biologists can measure the amount of a pollutant found within the mussel tissue and determine whether the use of a particular water source would prove dangerous to humans.
Pharmaceutical uses of mussels are also being explored, as results from cancer research indicate that clams and mussels have an extremely low incidence of tumors and appear to be cancer-resistant.
Pendleton Island was acquired by the Conservancy in 1983.
Protection of this area may have a global impact on the survival of several mollusk species, since three of the mussels which occur at this site exist in fewer than 10 sites worldwide, and one of these exists only at Pendleton Island.
The Conservancy's Clinch Valley Program works throughout this 2,200 square-mile watershed to protect key sites for mussels and other imperiled species. There are plans to reintroduce certain mussel species; Conservancy scientists will culture these young mussels at a nearby facility.