Releasing Mussels to by Shane D. Hanlon Recovering Waters

One of our nation’s biologi- mussels have been plagued by numerous cal hot spots, the 21,390 square human activities and are now considered miles (55,379 sq. kilometers) of the the most endangered faunal group in Upper River Basin (UTRB) North America. Mussel populations have provides habitat for a remarkable been decimated by impoundments; diversity of aquatic life. More than poorly managed mining operations; toxic 85 of the approximately 300 spills; industrial, domestic, and agricul- described North American tural pollution; and silt-laden waters freshwater mussel from eroding landscapes. The Fish and have been recorded here, Wildlife Service currently lists 30 mussel representing one of the most species of the UTRB under the Endan- diverse mussel assemblages gered Species Act (ESA) as endangered. in the world, with many Eleven species native to the basin in occurring nowhere else. Five historical times are believed to be major subbasins (the extinct. Only 26 of the nonlisted species Clinch/Powell, Holston, French Broad, are considered stable. Hiwassee, and Little Tennessee) contrib- Freshwater mussels provide us with ute to the UTRB, which stretches its important ecological benefits. They are a extensive network of tributaries through significant food source for many aquatic parts of Tennessee, , North and terrestrial . They filter Carolina, and . particulates and excess nutrients from A handful of 3-month-old juveniles of Prior to the industrial revolution, our rivers, thus improving water quality. the wavyrayed lampmussel freshwater mussels thrived in these Declining mussel populations signal (Lampsilis fasciola) propagated at Virginia Polytechnic Institute and waters. Over the past century, however, potentially serious environmental and State University and reared at the Virginia Department of Game and Inland Fisheries’ Aquatic Wildlife Research Center. Photo by Shane D. Hanlon

Site along the lower French Broad River, Tennessee, where common mussels are being released to test the suitability for the reintroduction of endangered mussels. Photo by Richard Biggins/USFWS

8 ENDANGERED SPECIES BULLETIN MARCH/APRIL 2003 VOLUME XXVIII NO. 2 public health problems. Because mussels program has collaborated with private mussels in 2001. More than 2,300 are long-lived and virtually immobile, landowners and other community juvenile mussels were released to the they cannot escape pollutants. Therefore, partners to conduct hundreds of stream Clinch River in Clinchport, including mussels have been referred to as “silent restoration projects on private lands in juveniles of the wavyrayed lampmussel sentinels” that indicate chronic impacts the UTRB. More than 50 miles (80 km) (Lampsilis fasciola) and two endangered to water quality. In addition, mussels’ of riparian corridor have been restored species, the Cumberlandian combshell lack of mobility renders them susceptible to benefit endangered mussels and a rich and oyster mussel. Researchers at the to massive die-offs from acute stresses, diversity of native fishes, snails, crayfish, Virginia Cooperative Fish and Wildlife such as chemical spills. Without mussels, amphibians, and other aquatic organ- Research Unit developed the propaga- these spills might go unnoticed, because isms. Improving habitat for mussels also tion techniques and assisted in the more mobile aquatic fauna can exit or benefits sport fisheries, improves water release. Research is underway to develop drift downstream of an impacted area quality for people, and increases aes- propagation technologies for other before perishing, leaving no visible trace thetic value. endangered mussels and to identify of the harm that can be done to the For many endangered mussel species, additional stream reaches suitable for aquatic ecosystem. habitat improvement alone may not be augmentation. The Service and its Prior to the first ESA listings of enough to prevent extinction. Densities partners plan to produce and release freshwater mussels in 1976, declining have become so low that natural repro- juvenile mussels of several imperiled freshwater mussel populations were duction can no longer sustain the species to augment additional popula- largely ignored. Today, numerous population. With support from the tions within the Clinch/Powell and North federal, state, tribal, and local agencies; Service, TWRA, and VDGIF, researchers Fork Holston in Virginia. conservation groups; and local commu- from the USGS/Biological Resources Using an ecosystem approach, the nities are recognizing the value of these Division at Virginia Polytechnic Institute Service’s conservation initiatives and animals and are advocating mussel and State University have worked partnerships are fundamental to prevent conservation. In the UTRB, local water- diligently to develop captive propagation the extinction of many freshwater mussel shed groups are growing in number. In techniques for endangered and threat- species. Through these efforts, popula- the Virginia portion alone, more than 20 ened mussels. From 1998 through 2001, tions of imperiled species may once nongovernmental organizations and nearly 260,000 juvenile mussels of eight again be able to sustain themselves and coalitions have spearheaded the demand endangered species and one of special thrive in restored habitats, benefitting not for improved water quality for biological concern were propagated and released only one of the richest aquatic communi- diversity, as well as for human use. to two major river systems (Clinch/ ties in the nation, but ultimately the Given the large scale at which the Powell and Hiwassee River systems) to human communities that depend on UTRB watershed has been altered, it is a augment declining mussel populations. good water quality and the conservation daunting task to protect and restore it. These species include the fanshell of aquatic biodiversity. Nevertheless, agencies and conservation (Cyprogenia stegaria), dromedary groups are making significant accom- pearlymussel (Dromus dromas), Shane D. Hanlon is an Endangered plishments. Since the early 1980s, under Cumberlandian combshell ( Species Recovery Biologist at the Service’s the leadership of the Service and with brevidens), oyster mussel (Epioblasma Southwestern Virginia Ecological Services the commitment of many partners, a capsaeformis), tan riffleshell (Epioblasma Field Office in Abingdon, Virginia; major mussel recovery program is florentina walkeri), snuffbox (Epioblasma (276)623-1233; [email protected]. underway. These partners include the triquetra), purple bean (Villosa Virginia Department of Game and Inland perpurpurea), birdwing pearlymussel Fisheries (VDGIF), U.S. Forest Service, (Lemiox rimosus=Conradilla caelata), and U.S. Geological Survey (USGS), Tennes- cracking pearlymussel (Hemistena lata). see Wildlife Resources Agency (TWRA), In 1998, the VDGIF established the Tennessee Valley Authority, Soil and Aquatic Wildlife Conservation Research Water Districts, Upper Tennessee River Center to expand propagation activities. Round Table, Nature Conservancy, and The facility, located at their Buller Fish Black Diamond Resource Conservation Culture Station near Marion, Virginia, has and Development, Inc. shown promising results in rearing Many streams throughout the UTRB juvenile mussels using water from the have been degraded by poor land nearby Holston River to simulate natural management practices. Since 1991, the river conditions. The VDGIF conducted Service’s Partners for Fish and Wildlife its first release of hatchery-reared

ENDANGERED SPECIES BULLETIN MARCH/APRIL 2003 VOLUME XXVIII NO. 2 9