Mussels are an integral part of most Southeastern aquatic ecosystems. They clean the water as they feed and act like the “canary in the coal mine” with regard to water quality. Declines in mussel populations are an indication that things are not in good shape. Mussels are one of the most imperiled group of aquatic animals in the Southeast. Propagation and culture of freshwater mussels has proven to be a useful tool in recovering and restoring mussel populations. To this end, Dale Hollow National Fish Hatchery (NFH) has become involved in a multi-partner effort to develop effective propagation and culture techniques for imperiled freshwater mussels species found in the Cumberland River drainage.
Tyler Hern, with the Tennessee Cooperative Fisheries Research Unit (Unit), was at the Dale Hollow NFH on April 23 to infest largemouth bass and spotted bass host fish with mussel glochidia (parasitic life stage) from two species of mussels. One of the mussel species is federally listed as endangered (Pink Mucket/Lampsilis abrupta) and the other species (Mucket/Actinonaias ligamentina) is currently considered stable. Tony Brady, Natchitoches NFH (LA), will be at the hatchery on Tuesday, May 14 to place the floating racks out in the lake embayment where the Corps moors their barge. Tony will place the infested fish into the cages in the lake on Wednesday, May 15. The glochidia will feed off of the host fish until they transform into juvenile mussels, when they drop off of the host fish and settle into the substrate (sand and gravel) on the bottom of the cage. This will take from 20 to 30 days following placement of glochidia on the gills (depending on water temperature). The juvenile mussels will be left to grow in the cages until this fall or until next spring. They are filter feeders and feed on plankton suspended in the water. The host fish were collected by the Tennessee Wildlife Resources Agency by electrofishing the upper end of Dale Hollow Lake on April 10 and will be released from the cages back into the lake when it is determined that all of the glochidia have transformed into juvenile mussels. Mussels produced will be used by the Unit for research projects focusing on species recovery. Friends Group members helped construct the cages on December 6, 2012.