Summary:
Vol. 69, No. 168, United States Fish and Wildlife Service (FWS), 50 CFR Part 17, RIN 1018-AI76, 69 FR 53136
Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for Five Endangered Mussels in the Tennessee and Cumberland River Basins
Action: FINAL RULE
Effective: 9/30/04
Background
The FWS has designated designate 13 river and stream segments in the Tennessee Cumberland River Basins, for a total of approximately 885 river as critical habitat for five endangered mussels: Cumberland elktoe ( Alasmidonta atropurpurea ), oyster mussel ( Epioblasma capsaeformis ), Cumberlandian combshell ( Epioblasma brevidens ), purple bean ( Villosa perpurpurea ), and rough rabbitsfoot ( Quadrula cylindrica strigillata ). All five mussels belong to the Unionidae family.
Background
- 10/12/00, the Southern Appalachian Biodiversity Project filed a lawsuit in U.S. District Court for the Eastern District of Tennessee against the FWS challenging the FWS’not-prudent critical habitat determination for the 5 Cumberlandian Region mussel species.
- 11/8/01, the District Court issued an order directing the FWS to re-evaluate the prudency determination for these five mussels and submit new proposed prudency determinations for the Cumberland elktoe to the Federal Register no later than 5/19/03, and for the remaining four mussels to the Federal Register no later than 6/16/03.
- 1/8/04 , the District Court extended FWS’ deadline to submit the final rule to the Office of the Federal Register to not later than 8/19/04 .
- 10/6/03 – 12/5/03, the comment period was reopened for submission of comments on a draft economic analysis, a technical correction and possible modification of Unit 8 Rock Creek, and to accommodate a public hearing which was held on October 29, 2003, in Tazewell County, Virginia (68 FR 57643).
Biological Information
- The five mussels live embedded in the bottom sand, gravel, cobble substrates of rivers and streams.
- The five mussels also have a unique life cycle that involves a parasitic stage on host fish. The presence of suitable host fish is considered an essential element in these mussels' life cycles.
- Because of their life cycle, small population sizes, and limited habitat availability, they are highly susceptible to competitive or predaceous nonnative species .
Five Elements that Critical Habitat is Designated to Protect for the Five Mussels
- Permanent, flowing stream reaches with a flow regime necessary for normal behavior, growth, and survival of all life stages of the five mussels and their host fish;
- Geomorphically stable stream and river channels and banks;
- Stable substrates, consisting of mud, sand, gravel, and/or cobble/boulder, with low amounts of fine sediments or attached filamentous algae;
- Water quality necessary for the normal behavior, growth, and survival of all life stages of the five mussels and their host fish; and
- Fish hosts with adequate living, foraging, and spawning areas for them.