Tennessee Valley Authority (TVA) and The Nature Conservancy (TNC) organized a release of three endangered species of mussels at Well Being Conference Center on October 6, 2016. Approximately 55 people representing more than ten state and federal agencies attended as well as environmental science professors and students from Lincoln Memorial University.
The funds for this ongoing effort to re-establish rare mussel species in the Powell River is funded in part from fines levied against Virginia coal mining companies for lethal spills into the Powell and Clinch Rivers some years ago. TVA is administering those funds to pay for research and for laboratories operated by the Virginia Tech Mollusk Lab and a State of Virginia facility which actually propagate and raise the juvenile mussels for one to two years before they are large enough to release.
Researchers spend several years evaluating over 100 miles of the Powell River to select ideal sites for the release of these rare mussels. Approximately six release sites were selected, once of which is on the boundary of Well Being Conference Center.
Mussels are of interest to these agencies because they are “indicator” species. Since they are filter feeders, whatever contaminants are in the river water, pass through the soft tissues of these immobile animals. If the mussel population of a river is thriving, it is very likely that the rest of the river inhabitants (fish, insects, crayfish, salamanders, birds and mammals) are also doing well. Mussels can also filter up to a gallon of water a day each, so a shoal of hundreds of thousands of mussels can have a significant effect of the clarity of the river. Here is a short time-lapse video of mussels cleaning up a fish tank. Mussels will feed on and filter out bacteria, small bits of algae and detritus. They can also sequester heavy metals in their shells.
Of the 36 species of mussels in the Powell River, 13 are federally listed as Threatened or Endangered (T&E). In the U.S., only the Clinch River has more T&E mussel species. This fact might sound like bad news, but the good news is that there are still mussels left to propagate. In many other rivers, the mussels have already completely died out. In Tennessee, over 10 mussel species have become extinct in the last 150 years.
Jess Jones, a restoration Biologist with the U.S. Fish and Wildlife Services, explained to the group the purpose of the reintroduction program and the unique life cycle of the mussels. He characterized the mussel life cycle as being more complex than any other organism that he knew of. Mussels reproduction is dependent on the presence of specific fish for each species of mussel. The mussel must induce the fish to strike at an appendage of the mussel that has evolved to look remarkably like common prey of the fish, like a minnow, a worm, or a larval fly.
Braven Beaty of The Nature Conservancy explained the importance of mussels to stabilize nutrients that would otherwise be washed downstream. These stabilized nutrients excreted by the mussels become food for a wide variety of insects, and other river inhabitants on which fish depend for food. Hence, the circle (of life) is unbroken.
The twenty LMU students were then invited into the river to place approximately 600 rare mussels – each tagged with a unique number – into the river.