For immediate release: July 15, 2004

Contact:

Phil Delphey, 612-725-3548, Ext. 206

EA 04-60

Service Releases Final Recovery Plan
for Higgins Eye Pearlymussel

A plan to recover the endangered Higgins eye pearlymussel, a freshwater mussel found in the Upper Mississippi River and its major tributaries, has been revised by the U.S. Fish and Wildlife Service and is now available. The new plan addresses threats to the species that were not anticipated when the original Higgins eye recovery plan was developed in 1983. Among the new threats considered in the revised recovery plan is the invasion of the Upper Mississippi River by non-native zebra mussels.

The revised recovery plan, developed by a team of state, federal and academic biologists, outlines numerous measures to recover Higgins eye. These include assessing and limiting the impact of zebra mussels, limiting construction in essential habitat areas, developing plans to enhance the safety of shipping toxic or hazardous materials, reintroducing Higgins eye into historical habitats where zebra mussels are not a threat, and identifying any contaminants that may affect the survival of Higgins eye populations.

Zebra mussels, which invaded the Upper Mississippi River in the early 1990s, are a profound threat to Higgins eye and other native species. Zebra mussels, native to eastern Europe, are known for their explosive population growth and tendency to affix themselves to native mussels and other surfaces. Masses of live and dead zebra mussels smother beds of native mussels that contain Higgins eye and other native species, which then die or become incapable of growth and reproduction. Zebra mussels may also compete with Higgins eye for food – both species filter small food particles, such as plankton, from the water. During the 1990s, zebra mussels devastated what may have been the largest population of Higgins eye, in the Mississippi River near Prairie du Chien, Wisconsin.

Higgins eye pearlymussel inhabits river bottoms that are relatively stable and primarily composed of sand or gravel. It was one of many freshwater mussel species heavily harvested for its shell to make mother-of-pearl buttons and pins. In addition to the severe threat currently posed by zebra mussels, degradation of the species’ large river habitats caused by the operation and maintenance of the navigation system on the Upper Mississippi River and localized impacts of construction projects also threaten Higgins eye populations. Adverse impacts to water quality, environmental contaminants from both point and non-point sources, and commercial harvest of native mussels may also threaten the species, which was listed as endangered in 1976.

The revised plan may be obtained from the Service's website, in PDF format, at http://endangered.fws.gov. For more information, or for assistance in obtaining a copy of the plan, contact Phil Delphey, U.S. Fish and Wildlife Service, Twin Cities Field Office, 4101 East 80th Street, Bloomington, Minnesota 55425-1665; telephone 612-725-3548, extension 206 (email: phil_delphey@fws.gov). TTY users may contact Mr. Delphey through the Federal Relay Service at 1-800-877-8339.

The U.S. Fish and Wildlife Service is the principal Federal agency responsible for conserving, protecting and enhancing fish, wildlife and plants and their habitats for the continuing benefit of the American people. The Service manages the 95-million-acre National Wildlife Refuge System, which encompasses 544 national wildlife refuges, thousands of small wetlands and other special management areas. It also operates 69 national fish hatcheries, 63 Fish and Wildlife Management offices and 81 ecological services field stations. The agency enforces federal wildlife laws, administers the Endangered Species Act, manages migratory bird populations, restores nationally significant fisheries, conserves and restores wildlife habitat such as wetlands, and helps foreign governments with their conservation efforts. It also oversees the Federal Assistance program, which distributes hundreds of millions of dollars in excise taxes on fishing and hunting equipment to state fish and wildlife agencies.

-FWS-