A female Higgins' eye pearlymussel with swollen "brooding" gills that contain thousands of mature larvae. - Photo courtesy of the Minnesota DNR

These mature Higgins' eye pearlymussel larvae found in the Upper Mississippi River are the first to be discovered from an artificially propagated mussel. - Photo courtesy of the Minnesota DNR

A consortium of federal and state partners, led by fisheries and ecological services staff from the Midwest Region of the U.S. Fish and Wildlife Service has been involved in an active range wide recovery effort for the federally endangered Higgin’s eye pearlymussel since 1999. 

From the program's humble beginnings in a small rearing area at Genoa (Wisconsin) National Fish Hatchery, the program has produced millions of young mussels for recovery areas throughout the species current and former range.  Additionally, thousands of advanced growth mussels, those mussels over one year old and ranging in size from 1-3 inches, have been stocked in areas within the Upper Mississippi River to create new breeding populations of the mussel.  During scheduled assessment operations in early fall 2005, state and federal biologists detected viable larvae in propagated animals in the wild. These mussels were the progeny from operations carried out at the Genoa NFH in cooperation with multiple state partners and the U.S. Army Corps of Engineers. Samples collected from several of the recovery sites by divers from the Minnesota Department of Natural Resources showed 100 percent of stocked female mussels examined to be brooding (holding) viable larval mussels. 

This exciting news is conformation that a major hurdle in recovery has been reached for this species.  The discovery shows that animals produced under artificial culture techniques have reached maturity, bred, and produced viable larvae under natural conditions. The next step that biologists with the project hope to detect is the discovery of second generation mussels located at the recovery sites that can be attributed to the initial stockings.

For more information of this exciting news or other projects associated with the Genoa National Fish Hatchery contact Doug Aloisi or Roger Gordon at 608-689-2605 or e-mail roger_gordon@fws.gov.