June 16, 2011 – Healthy rivers and streams need freshwater mussels. Freshwater mussels feed by filtering bacteria, algae, and other small particles from the water which improves water quality. However, freshwater mussels have become the nation's most endangered group of animals. Several species of rare mussels live in streams that flow through military lands. For example, the upper Nottoway River on Fort Pickett, near Blackstone Virginia, is home to one of the few remaining viable populations of the Atlantic pigtoe mussel (Fusconaia masoni) remaining in Virginia. Populations of the Atlantic Pigtoe are in precipitous decline throughout their range, and the Department of Defense (DoD) classifies this species as a “at-risk”.
DoD is funding a cooperative research effort through the DoD Legacy Resource Management Program to proactively address declining populations of the Atlantic pigtoe before it is listed as endangered. Biologists with the Conservation Management Institute at Virginia Tech and the U.S. Fish and Wildlife Service are propagating this species for reintroduction into the Nottoway River at Fort Pickett.
Propagation and culture of juvenile mussels for release into the wild is a component of many endangered species recovery plans. Freshwater mussel reproduction is a complex, multi-stage process that is dependent upon the season and water conditions. Mussel larvae, called glochidia, survive and grow by temporarily attaching themselves to the gills of a host fish and then dropping off into suitable substrate as they mature. The relationship between mussel and host fish can be species-specific with a particular mussel species relying on a specific host fish species. A key component of this project was to accurately identify the host fish species for the Atlantic Pigtoe which will facilitate propagation of the species.
By identifying the host fish species and refining techniques for feeding and holding adult and juvenile mussels we will be better able to raise captive-reared mussels and provide conditions that will enhance their chances of survival in the wild. Future work will focus on researching optimal water conditions and habitat used by the Atlantic Pigtoe in order to target areas that are well-suited for release and reintroduction.
Military lands are a valuable and finite commodity and their conservation is not only essential to the maintenance and sustainability of suitable training lands but can also provide unique opportunities for proactive natural resource conservation. Proactive conservation and reintroduction of the Atlantic Pigtoe at Fort Pickett will support more stable populations over a broad geographical range thus reducing potential federal listing and subsequent encroachment on Military training and readiness.
Note: This article was included in the US Fish and Wildlife Service's 2011 Spring edition of the Endangered Species Bulletin