Approved Recovery Plan for the Higgins Eye Pearlymussel (Lampsilis higginsii

AGENCY:

Fish and Wildlife Service, Interior.

ACTION:

Notice of document availability.

SUMMARY:

The U.S. Fish and Wildlife Service (Service) announces the availability of the approved recovery plan for the Higgins eye pearlymussel (Lampsilis higginsii). This species is federally listed as endangered under the Endangered Species Act of 1973 (Act), as amended (16 U.S.C. 1531 et seq.); it occurs in the Mississippi River and tributaries to the Mississippi River in Illinois, Iowa, Minnesota, Missouri, and Wisconsin.

Actions needed for recovery of the Higgins eye pearlymussel include alleviating threats posed by exotic species, especially zebra mussels (Dreissena polymorpha), protecting remaining populations, and reintroducing the species into habitats that it historically occupied.

ADDRESSES:

This recovery plan is available from the following addresses:

1. Field Supervisor, U.S. Fish and Wildlife Service, Twin Cities Field Office, 4101 East 80th Street, Bloomington, MN 55425.

2. The World Wide Web at: http://endangered.fws.gov/recovery/index.html#plans.

FOR FURTHER INFORMATION CONTACT:

Mr. Phil Delphey, Twin Cities Field Office, (see ADDRESSES section No. 1 above), telephone (612) 725-3548 ext. 206. TTY users may contact Mr. Delphey through the Federal Relay Service at (800) 877-8339.

SUPPLEMENTARY INFORMATION:

Background

Recovery of endangered or threatened animals or plants is a primary goal of the Service's endangered species program. A species is considered recovered when its status has been improved to the point at which listing is no longer appropriate under the criteria set out in section 4(a)(1) of the Act. Recovery plans describe actions considered necessary for the conservation of the species, establish criteria for delisting species, and provide estimates of the time and cost for implementing the measures needed for recovery.

The Act requires the development of recovery plans for listed species unless such a plan would not promote the conservation of a particular species. Section 4(f) of the Act, as amended in 1988, requires that public notice and the opportunity for public review and comment be provided during recovery plan development. Information presented during the comment period has been considered in the preparation of the approved recovery plan and is summarized in an appendix to the recovery plan. We will forward substantive comments regarding recovery plan implementation to appropriate Federal agencies and other entities so that they can take these comments into account during the course of implementing recovery actions.

Higgins eye pearlymussel is a large river species occupying stable substrates that vary from sand to boulders; it does not occur in firmly packed clay, flocculent silt, organic material, bedrock, concrete or unstable sand. Water velocities should be less than 1 m/s during periods of low discharge. The species is usually found in mussel beds that contain at least 15 other species. The density of all mussels in the bed typically exceeds 10/m². Although zebra mussels are currently the most important threat to L. higginsii, construction activities and environmental contaminants may also pose significant threats. This revised plan includes ten Essential Habitat Areas: six in the Mississippi River between river miles 489 and 656; one in the Wisconsin River; and three in the St. Croix River, which empties into the Mississippi River at river mile 811, just downstream of Minneapolis/St. Paul, Minnesota. Higgins eye also occurs elsewhere in the Mississippi River and recently has been reintroduced into several tributaries of the Mississippi River in which it historically occurred. This revised plan recommends that surveys be conducted in several specific areas to better describe other potentially important habitats.

The objective of the recovery plan is to provide a framework for the recovery of Higgins eye pearlymussel so that protection by the Act is no longer necessary. Higgins eye may be considered for reclassification from Endangered to Threatened when the following occurs: (1) At least five identified Essential Habitat Areas contain reproducing, self-sustaining populations of L. higginsii that are not threatened by zebra mussels; (2) a freshwater mussel toxicity database is completed, and specific sediment and water quality parameters in Essential Habitat Areas and reestablishment areas have been characterized; and (3) harvest of freshwater mussels is prohibited by law or regulation in Essential Habitat Areas.

Recovery will be achieved and the species removed from the list of Threatened and Endangered Wildlife (50 CFR part 17) when the following criteria are met: (1) Populations in at least five Essential Habitat Areas are reproducing, self-sustaining, not threatened by zebra mussels, and are sufficiently secure to assure long-term viability of the species; (2) zebra mussels are not present in locations where they or their offspring are likely to adversely affect L. higginsii populations in any of the five identified Essential Habitat Areas; (3) the use of double hull barges or other actions have alleviated the threat of spills to each of the identified Essential Habitat Areas; (4) L. higginsii habitat information and protective responses to conserve each of the identified Essential Habitat Areas have been incorporated into all applicable spill contingency planning efforts; and (5) harvest of freshwater mussels is prohibited by law or regulation in Essential Habitat Areas. Water quality criteria may be added to the delisting criteria upon completion of the tasks referred to in the reclassification criteria.

Authority: The authority for this action is section 4(f) of the Endangered Species Act, 16 U.S.C. 1533(f).