Biologists in scuba gear and a partnership of workers armed with syringes and plastic buckets are among the front-line warriors in the fight to save one of the Upper Mississippi Rivers most imperiled species - the Higgins eye pearlymussel. Beginning this week, biologists with the U.S. Fish and Wildlife Service (Service), and the Minnesota and Wisconsin Natural Resource Departments will collect federally endangered Higgins eye mussels and produce young mussels at the Services Genoa National Fish Hatchery in Genoa, Wisconsin, for eventual release back into their natural habitat.
Freshwater mussels like the Higgins eye are among the countrys greatest at-risk species and face a multitude of threats, ranging from degraded water quality to loss of riverbed habitat. But the most pressing danger to the Higgins eye and many other native mussels is the spread of the prolific, non-native zebra mussel which competes with native species for food and oxygen and can virtually smother other mussels.
"Our goal with the hatchery project is to take adult Higgins eye mussels from areas already infested with zebra mussels, raise young mussels in the hatchery, and then release them in areas where they should be safe from that threat," said Pam Thiel, fisheries biologist with the U.S. Fish and Wildlife Service. "We hope we can keep this species going in the hatchery and in some remaining suitable natural habitats to prevent zebra mussels from eliminating the Higgins eye."
"We have a special facility at the hatchery -- we call it the "Clam Palace" -- where we work with the Higgins eye. Were hopeful that techniques we developed in 2000, the first year that we attempted this, will allow us to raise and release thousands of juvenile Higgins eye mussels, as well as some of the host fish with mussel larvae still attached," said Todd Turner, manager of Genoa National Fish Hatchery.
Biologists from the states of Minnesota and Wisconsin will search the bottom of the St. Croix River near Hudson, Wisconsin, for female Higgins eye mussels. These "gravid" females -- those that have developing mussel larvae within them
