A female northern riffleshell displaying her white mantle tissue. This display is used to attract the fish host. When the fish host comes close to investigate, the mussel closes the shell, capturing the fish inside. Once the larvae have attached, the fish is released alive. Photo by Rachel Mair.

Juvenile northern riffleshell produced at White Sulphur Springs National Fish Hatchery. Photo by Rachel Mair.

The following ARS report is a clarification of the previous report titled "Aquatic Species Conservation: The northern riffleshell, a federally endangered freshwater mussel, spawns in captivity at White Sulphur Springs National Fish Hatchery" submitted on 2/7/2008.

Three years of work at White Sulphur Springs National Fish Hatchery (WSSNFH) to identify suitable diets and feeding regimes for the propagation and recovery of endangered freshwater mussels has produced exciting results.  Adult northern riffleshell, a federally endangered freshwater mussel, spawned and became gravid in refugia at WSSNFH in 2007.  To our knowledge and based on conversations with key researchers, this appears to be the first record of the endangered northern riffleshell successfully spawning in captivity.  Seizing on this momentous occasion, biologists with WSSNFH began research to improve propagation and culture methods for this rare freshwater mussel, opening the door for success with other endangered freshwater mussels at WSSNFH.  To date the juvenile mussels resulting from this spawning success continue to grow and thrive … 9 months later.                                            

Adult northern riffleshell were rescued from a new bridge project on the Allegheny River in Clarion County, PA and sent to refugia at WSSNFH.  This successful salvage and refugia was conducted through the efforts of many partners including the Pennsylvania Department of Transportation, the Pennsylvania Field Office of the U.S. Fish and Wildlife Service, the Ohio River Islands National Wildlife Refuge, the West Virginia Division of Natural Resources, the Environmental Protection Agency, the Northeast Fishery Center and the WSSNFH. During their stay at the hatchery, biologists studied substrate preferences, flow rate requirements and feeding physiology in hopes of keeping them healthy.  Spawning requires a significant investment of body energy, indicating our efforts to maintain their health were successful.   Juvenile mussels produced at WSSNFH as a result of the successful spawning will be used to augment existing populations in the Allegheny River.