# Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for the Fluted Kidneyshell and Slabside Pearlymussel > Briefs, arguments, decisions, and more. URL: https://www.frixlaw.com/law-library/documents/fr%3A2013-23357 ## Record - **Collection:** Federal Register - **Document type:** Rule - **Published:** September 26, 2013 - **Citation:** 78 FR 59556 ## Text DEPARTMENT OF THE INTERIOR Fish and Wildlife Service 50 CFR Part 17 [Docket No. FWS-R4-ES-2013-0026; 4500030113] RIN 1018-AZ48 Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for the Fluted Kidneyshell and Slabside Pearlymussel AGENCY: Fish and Wildlife Service, Interior. ACTION: Final rule. SUMMARY: We, the U.S. Fish and Wildlife Service (Service), designate critical habitat for the fluted kidneyshell ( Ptychobranchus subtentum ) and slabside pearlymussel ( Pleuronaia dolabelloides ) under the Endangered Species Act of 1973, as amended (Act). These two species are endemic to portions of the Cumberland and Tennessee River systems of Alabama, Kentucky, Mississippi, Tennessee, and Virginia. In total, approximately 2,218 river kilometers (1,380 river miles) in Alabama, Kentucky, Mississippi, Tennessee, and Virginia fall within the boundaries of the critical habitat designation. The effect of this regulation is to designate critical habitat for the fluted kidneyshell and slabside pearlymussel under the Act for the conservation of the species. DATES: This rule is effective on October 28, 2013. ADDRESSES: This final rule is available on the Internet at http://www.regulations.gov and at http://www.fws.gov/cookeville. Comments and materials we received, as well as supporting documentation we used in preparing this final rule, are available for public inspection at http://www.regulations.gov. All of the comments, materials, and documentation that we considered in this rulemaking are available by appointment, during normal business hours, at: U.S. Fish and Wildlife Service, Tennessee Ecological Services Field Office, 446 Neal Street, Cookeville, TN 38501; 931-528-6481 (telephone); 931-528-7075 (facsimile). The coordinates or plot points or both from which the maps are generated are included in the administrative record for this critical habitat designation and are available at http://www.regulations.gov at Docket No. FWS-R4-ES-2013-0026 and at the Tennessee Ecological Services Field Office (see FOR FURTHER INFORMATION CONTACT ). Any additional tools or supporting information that we developed for this critical habitat designation will be available at the Web sites and field office address given above and may also be included in the preamble of this rule. FOR FURTHER INFORMATION CONTACT: Mary Jennings, Field Supervisor, U.S. Fish and Wildlife Service, Tennessee Ecological Services Field Office, 446 Neal Street, Cookeville, TN 38501; telephone 931-528-6481; facsimile 931-528-7075. If you use a telecommunications device for the deaf (TDD), call the Federal Information Relay Service (FIRS) at 800-877-8339. SUPPLEMENTARY INFORMATION: Executive Summary Why we need to publish a rule. This is a final rule to designate critical habitat for the fluted kidneyshell ( Ptychobranchus subtentum ) and slabside pearlymussel ( Pleuronaia dolabelloides ). Under the Endangered Species Act (Act), when we determine that a species is endangered or threatened we must designate critical habitat to the maximum extent prudent and determinable. Designations of critical habitat can only be completed by issuing a rule. Section 4(b)(2) of the Act states that the Secretary shall designate critical habitat on the basis of the best available scientific data after taking into consideration the economic impact, national security impact, and any other relevant impact of specifying any particular area as critical habitat. The areas we are designating in this rule constitute our current best assessment of the areas that meet the definition of critical habitat for the fluted kidneyshell and slabside pearlymussel. Here we are designating approximately 2,218 river kilometers (rkm) (1,380 river miles (rmi)) of stream channel in five States as critical habitat. For the fluted kidneyshell, we are designating 24 units covering approximately 1,899 rkm (1,181 rmi) of critical habitat in Limestone County, Alabama; Jackson, Laurel, McCreary, Pulaski, Rockcastle, and Wayne Counties, Kentucky; Bedford, Claiborne, Cocke, Fentress, Franklin, Giles, Grainger, Greene, Hamblen, Hancock, Hickman, Humphreys, Jefferson, Knox, Lincoln, Marshall, Maury, Moore, Morgan, Overton, Perry, Pickett, Polk, Scott, and Sevier Counties, Tennessee; and Bland, Lee, Russell, Scott, Smyth, Tazewell, Washington, and Wythe Counties, Virginia. For the slabside pearlymussel, we are designating 13 units covering approximately 1,562 rkm (970 rmi) of critical habitat in Colbert, Jackson, Limestone, Madison, and Marshall Counties, Alabama; Tishomingo County, Mississippi; Bedford, Bledsoe, Claiborne, Cocke, Franklin, Giles, Greene, Hamblen, Hancock, Hickman, Humphreys, Lincoln, Marion, Marshall, Maury, Moore, Perry, Polk, and Sequatchie Counties, Tennessee; and Bland, Lee, Russell, Scott, Smyth, Tazewell, Washington, and Wythe Counties, Virginia. This rule consists of a final rule designating critical habitat for the fluted kidneyshell and slabside pearlymussel. Elsewhere in today's Federal Register , we list both species as endangered under the Act. Peer review and public comment. We sought comments from independent specialists to ensure that our designation is based on scientifically sound data, assumptions, and analyses. We requested opinions from eight knowledgeable individuals with scientific expertise to review our technical assumptions and analysis, and to determine whether or not we used the best available information. Only one of the two peer reviewers who responded commented specifically on the critical habitat designation. This peer reviewer generally concurred with our methods and conclusions, and provided additional information, clarifications, and suggestions to improve this final rule. Information we received from peer review is incorporated in this final designation. We received three comments from the public regarding the proposed critical habitat designation and the draft economic analysis (DEA). We addressed these comments and incorporated public input into this final designation. Previous Federal Actions We proposed listing the fluted kidneyshell and slabside pearlymussel as endangered under the Act with critical habitat on October 4, 2012 (77 FR 60804), and announced the availability of a DEA on April 29, 2013 (78 FR 25041). The final listing rule can be found elsewhere in today's Federal Register . All other previous Federal actions for these species are described in the proposed rule (77 FR 60804). Summary of Comments and Recommendations We requested written comments from the public on the proposed designation of critical habitat for the fluted kidneyshell and slabside pearlymussel during two comment periods. The first comment period associated with the publication of the proposed rule (77 FR 60804) opened on October 4, 2012, and closed on December 3, 2012. We also requested comments on the proposed critical habitat designation and associated DEA during a comment period that opened on April 29, 2013, and closed on May 29, 2013. We received one request for a public hearing. We held a public hearing in Abingdon, Virginia, on May 14, 2013. We also contacted appropriate Federal, State, and local agencies; scientific experts and organizations; and other interested parties and invited them to comment on the proposal. Newspaper notices inviting general public comment were published in newspapers covering all affected counties in Alabama, Kentucky, Mississippi, Tennessee, and Virginia. During the first comment period, we received three comment letters directly addressing the proposed critical habitat designation. During the second comment period, we received one comment letter addressing the proposed critical habitat designation or the DEA. During the May 14, 2013, public hearing, one organization made comments on the proposed designation of critical habitat and DEA. All substantive information provided during both comment periods and the public hearing has either been incorporated directly into this final determination or is addressed below. Peer Reviewer Comments In accordance with our peer review policy published on July 1, 1994 (59 FR 34270), we solicited expert opinion from eight knowledgeable individuals with scientific expertise that included familiarity with the two mussels and their habitats, biological needs, and threats. We received responses from two of the peer reviewers, but only one of them commented specifically on the proposed critical habitat designation. We reviewed all comments we received from the peer reviewer for substantive issues and new information regarding the proposed designation of critical habitat for the two mussels. Peer reviewer comments are addressed in Comments 1, 2, and 3 below; addressed in the Summary of Changes from Proposed Rule section; and incorporated into the final rule as appropriate. (1) Comment: The Special Management Considerations or Protection section fails to list the Tennessee Wildlife Resources Agency (TWRA) mussel sanctuaries located in the Powell, Clinch, Duck, and Hiwassee Rivers as effective conservation measures. The mussel sanctuaries prohibit the taking of mollusks by any means at all times and prohibit the degradation or destruction of aquatic habitat. Our Response: We agree that the TWRA mussel sanctuaries are protective of the fluted kidneyshell and slabside pearlymussel, and we have incorporated this into the Special Management Considerations or Protection section of this final rule. (2) Comment: In several critical habitat unit descriptions, the host fish species for the slabside pearlymussel are identified but not the host fish for the fluted kidneyshell. Host fish for the fluted kidneyshell are also found in these rivers (Nolichucky, Hiwassee, Elk, and Buffalo Rivers). Our Response: We agree the host fishes for the fluted kidneyshell are found in the Nolichucky (FK18), Hiwassee (FK21), Elk (FK22), and Buffalo (FK24) Rivers. However, under the Act (16 U.S.C. 1531 et seq. ) and its implementing regulations, we are only required to identify the physical and biological features (PBFs) essential to the conservation of species in areas occupied at the time of listing, focusing on the features' primary constituent elements (PCEs). Under the second prong of the Act's definition of critical habitat, we can designate critical habitat in areas outside the geographical area occupied by the species at the time it is listed (i.e., unoccupied units), upon a determination that such areas are essential for the conservation of the species. Because units FK21, FK22, and FK24 are unoccupied by the fluted kidneyshell at the time of listing, the presence of the host fishes (a PCE for the fluted kidneyshell) was not considered in the determination of those units and therefore not identified in the unit descriptions. The critical habitat designation for these units is based upon the determination that they are essential for the conservation of the species. However, Unit FK18 has been changed to occupied based on information provided by peer reviewers (see next comment), and the presence of fish hosts for the fluted kidneyshell has been added to the description of Unit FK18 (see Final Critical Habitat Designation, below). (3) Comment: The Nolichucky River, Tennessee, Unit FK18 for the fluted kidneyshell, has been proposed as unoccupied critical habitat even though the site retains large numbers of reintroduced adults from stocking efforts over the past 8 years. However, the Duck River has been proposed as occupied based on similar reintroduction efforts. Explain this inconsistency. Our Response: In the Duck River, the fluted kidneyshell population is a result of a successful reintroduction program implemented by TWRA and other conservation partners, resulting in the recruitment of the species in the river. In 2010, six individuals were collected during a quantitative survey at Lillard's Mill in the Duck River, confirming some level of survival and persistence of the reintroduced population (Hubbs et al. 2011, p. 18). We had no information at the time of the proposed rule to show that monitoring efforts in the Nolichucky River had confirmed the survival and persistence of reintroduced fluted kidneyshell. Since that time, Hubbs (2012, pers. comm.) confirmed that the Nolichucky River retains a large number of adult individuals. Therefore, we have changed the designation of critical habitat in the Nolichucky River from unoccupied to occupied and revised the designation accordingly. Federal Agency Comments (4) Comment: The U.S. Department of Agriculture, Natural Resources Conservation Service (NRCS), in Kentucky, would like to explore opportunities to focus conservation practices including the Wildlife Habitat Incentives Program (WHIP) and the Environmental Quality Incentives Program on water quality improvement and restoration in any areas designated as critical habitat for the fluted kidneyshell and other aquatic organisms. Our Response: The Service concurs that Farm Bill practices implemented by the NRCS can improve water quality and benefit rare aquatic species. The Service will continue to work with NRCS to identify aquatic habitats for rare aquatic species that would benefit from conservation practices on private lands. One example of a successful partnership between NRCS and the Service's Kentucky Field Office is the Mill Branch Stream Restoration Project in which 700 meters (m) (2,300 feet (ft)) of stream was completely restored and a fish passage installed to open an additional 1,524 to 2,438 m (5,000 to 8,000 ft) of stream for the federally threatened blackside dace ( Phoxinus [=Chrosomus] cumberlandensis ) in Knox County, Kentucky. This project was completed through the WHIP program. Public Comments (5) Comment: The Service has failed to prepare a DEA or to announce when the public will have the opportunity to comment on that analysis, hindering the public's ability to meaningfully comment on the complete picture of factors impacting the Service's determination and whether or not the Service has complied with all legal obligations that should shape the final rule. Our Response: We proposed listing the fluted kidneyshell and slabside pearlymussel as endangered under the Act with critical habitat (77 FR 60804) on October 4, 2012, and announced the availability of a DEA (78 FR 25041) on April 29, 2013. Publication of the DEA after the proposed critical habitat rule is published has been standard practice with critical habitat rules. The Service reopened the comment period for 30 days (through May 29, 2013) to allow comments on the DEA. Additionally, we held a public hearing in Abingdon, Virginia, on May 14, 2013. (6) Comment: During the public hearing, one commenter stated that the DEA is not based on sufficient data and many of the aspects of it appear to be incorrect. The methodology used to reach the estimates is poorly explained and the discount rate selected appears to be too high. The same commenter also stated: “The draft economic analysis did not quantify, quote, indirect economic impacts associated with time delays and a misperception of the regulatory burden imposed by the proposed critical habitat designation, end quote, because of, quote, a lack of available data, end quote.” Our Reponse: Our economic analysis is based on the best available data and applies standard methods for assessing the impacts of critical habitat designation. The Office of Management and Budget (OMB) recommends that a 7 percent discount rate be applied as a base case for regulatory analysis (OMB 2003). The DEA and final economic analysis (FEA) also report results using a discount rate of 0 percent and 3 percent for comparison. There were insufficient data to quantify and monetize indirect economic impacts of the critical habitat designation. These are addressed qualitatively in the analysis to allow the Service to consider these impacts in our determination. Based on our previous data collection, we have included additional information regarding time delays associated with section 7 consultations in the FEA. (7) Comment: During the public hearing, one commenter stated there is no indication in the DEA that the authors consulted with the Virginia Division of Mines, Minerals, and Energy, or with any other coal companies concerning the direct and indirect economic impact of the proposed critical habitat designation on the coal mining industry. Our Response: The Virginia Division of Mines, Minerals, and Energy declined to provide information for the economic analysis. Phone and email requests for information from the Virginia Coal Association, Virginia Mining Association, and Eastern Coal Council were not returned. (8) Comment: The Service published a proposed rule that had not undergone peer review, thereby not necessarily reflecting sound science, as required by section 4 of the Act and as required under section 515(b)(2)(A) of the Information Quality Act. Rather than conducting peer review prior to publication of the proposed rule, which would allow the public to view a fully scientifically vetted proposal, the Service opted to conduct peer review contemporaneously with the public comment period. Additionally, there is no indication that the public will have an opportunity to review and comment on the rule as informed by peer review, which is troubling due to the Service relying on decades-old data (e.g., concluding a population to be extant if found post-1980). Our Response: In accordance with our peer review policy published on July 1, 1994 (59 FR 34270), we solicited expert opinion from eight knowledgeable individuals with scientific expertise that included familiarity with the two mussels and their habitats, biological needs, and threats. In keeping with our policy, we contacted these peer reviewers after the proposed rule was published in the Federal Register . We received responses from two of the peer reviewers. We posted all of the comments we received on the October 4, 2012, proposal to designate critical habitat for the fluted kidneyshell and slabside pearlymussel (77 FR 60804), as well as the document making available the DEA for that proposed action (78 FR 25041; April 29, 2013), on the Internet at http://www.regulations.gov under Docket No. FWS-R4-ES-2013-0026. We reviewed all comments we received from the peer reviewers and others for substantive issues and new information regarding the proposed designation of critical habitat for the two mussels. The peer reviewers generally concurred with our conclusions and provided additional information on taxonomic classification, life history, current distribution, and threats. Peer reviewer comments are addressed in the Peer Reviewer Comments section above, addressed in the Summary of Changes from Proposed Rule section below, and incorporated into this final rule as appropriate. (9) Comment: The proposed rule would impose significant and unwarranted regulatory burdens with regard to consultation requirements under section 7 of the Act as they apply to designated critical habitat. Consultation in unoccupied habitats, where there are no specimens of the fluted kidneyshell or slabside pearlymussel, would be unduly burdensome, unwarranted, and unlikely to foster support for the conservation of these species. Our Response: For the most part, consultation requirements under section 7 of the Act already exist for other listed species throughout the critical habitat designation for the fluted kidneyshell and slabside pearlymussel. Eleven critical habitat units proposed for both the fluted kidneyshell and slabside pearlymussel are currently designated as critical habitat under the Act for other federally listed species. All of the critical habitat units being designated for the fluted kidneyshell and slabside pearlymussel, including the unoccupied units, contain historical or extant records of federally listed or proposed species, except for the Wolf River and Town Branch and West Fork Obey River, Tennessee. Specifically: • Some streams we are designating as critical habitat that are unoccupied by at least one of the species are occupied either by the other species or by another federally listed mussel species. For instance, the Buffalo River Unit (Unit FK24 and SP13) is unoccupied critical habitat for the fluted kidneyshell, but is occupied critical habitat for the slabside pearlymussel. • Some streams we are designating as critical habitat for the fluted kidneyshell and slabside pearlymussel have not been previously designated as critical habitat for other species, but other federally listed species occur in these streams. For instance, the Holston River (Unit FK19) and French Broad River (Unit FK20), which we are designating as unoccupied critical habitat for the fluted kidneyshell, contain other federally listed species such as the pink mucket ( Lampsilis abrupta ). The Service is designating as critical habitat streams that are outside the geographical area occupied by the species because we have determined that: (1) Such areas are essential for the conservation of the species, and (2) designation of only occupied habitats is not sufficient to conserve these two species. Unoccupied habitats provide additional habitat for population expansion and promotion of genetic diversity, which will decrease the risk of extinction for these two species. As indicated above, the majority of these habitats already possess listed species or their critical habitat, and therefore Federal actions in those areas would require consultation under the Act, regardless of whether or not critical habitat was designated for these two mussels. Summary of Changes From Proposed Rule As a result of the comments we received during the public comment periods (see above), we made the following changes to the final critical habitat rule: (1) We added TWRA mussel sanctuary information to the Special Management Considerations or Protection section. (2) We changed Unit FK18 (Nolichucky River) from unoccupied to occupied for the fluted kidneyshell to reflect the successful reintroduction program implemented by TWRA and other conservation partners. (3) In Table 4, we added pink mucket to the list of species that occur in the Holston River (Unit FK19). (4) We corrected the description for Unit FK19 to reflect that slabside pearlymussel and its host fish are known from the Holston River (not the French Broad River). (5) We revised the description of Unit FK24 and SP13 (Buffalo River). The channel is not stable, as we stated in the proposed rule, but has destabilized substrates. While preparing the final critical habitat rule, we also made the following corrections and modifications to Table 3 (Table 5 in the proposed rule): (1) We corrected the length of overlap for rabbitsfoot ( Quadrula cylindrica cylindrica ) in Unit SP9 (Paint Rock River), Unit SP11 (Bear Creek), and Unit FK23 and SP12 (Duck River). (2) We calculated total overlap lengths for critical habitat units and nonessential experimental populations (NEPs) separately. (3) We added a note to clarify how the total overlap lengths were calculated. In Table 4 (Table 6 in the proposed rule), we made the following corrections to the list of species that occur in critical habitat units: (1) We added rough rabbitsfoot ( Q. c. strigillata ) to Unit FK10 (Indian Creek). (2) We deleted tan riffleshell ( Epioblasma florentina walkeri (=E. walkeri )) and white wartyback ( Plethobasus cicatricosus ) from Unit FK17 and SP5 (Powell River). (3) We added oyster mussel ( E. capsaeformis ) to and deleted pink mucket from Unit FK18 and SP6 (Nolichucky River). (4) We added birdwing pearlymussel ( Lemiox rimosus) and cracking pearlymussel ( Hemistena lata) to Unit FK20 (French Broad River). (5) We added oyster rmussel to Unit SP9 (Paint Rock River). (6) We added Alabama lampmussel ( Lampsilis virescens ) and Cumberlandian combshell ( E. brevidens ) to Unit SP11 (Bear Creek) and deleted finerayed pigtoe ( Fusconaia cuneolus ) from the same unit. (7) We deleted orangefoot pimpleback ( Plethobasus cooperianus ) from Unit FK23 and SP12 (Duck River). Background Critical habitat is defined in section 3 of the Act as: (1) The specific areas within the geographical area occupied by the species, at the time it is listed in accordance with the Act, on which are found those physical or biological features (a) Essential to the conservation of the species, and (b) Which may require special management considerations or protection; and (2) Specific areas outside the geographical area occupied by the species at the time it is listed, upon a determination that such areas are essential for the conservation of the species. Conservation, as defined under section 3 of the Act, means to use, and the use of, all methods and procedures that are necessary to bring an endangered or threatened species to the point at which the measures provided pursuant to the Act are no longer necessary. Such methods and procedures include, but are not limited to, all activities associated with scientific resources management such as research, census, law enforcement, habitat acquisition and maintenance, propagation, live trapping, and transplantation, and, in the extraordinary case where population pressures within a given ecosystem cannot be otherwise relieved, may include regulated taking. Critical habitat receives protection under section 7 of the Act through the requirement that Federal agencies ensure, in consultation with the Service, that any action they authorize, fund, or carry out is not likely to result in the destruction or adverse modification of critical habitat. The designation of critical habitat does not affect land ownership or establish a refuge, wilderness, reserve, preserve, or other conservation area. Such designation does not allow the government or public to access private lands. Such designation does not require implementation of restoration, recovery, or enhancement measures by non-Federal landowners. Where a landowner requests Federal agency funding or authorization for an action that may affect a listed species or critical habitat, the consultation requirements of section 7(a)(2) of the Act would apply, but even in the event of a destruction or adverse modification finding, the obligation of the Federal action agency and the landowner is not to restore or recover the species, but to implement reasonable and prudent alternatives to avoid destruction or adverse modification of critical habitat. Under the first prong of the Act's definition of critical habitat, areas within the geographical area occupied by the species at the time it was listed are included in a critical habitat designation if they contain physical or biological features (1) which are essential to the conservation of the species, and (2) which may require special management considerations or protection. For these areas, critical habitat designations identify, to the extent known using the best scientific and commercial data available, those physical or biological features that are essential to the conservation of the species (such as space, food, cover, and protected habitat). In identifying those physical or biological features within an area, we focus on the principal biological or physical constituent elements (primary constituent elements such as roost sites, nesting grounds, seasonal wetlands, water quality, tide, soil type) that are essential to the conservation of the species. Under the second prong of the Act's definition of critical habitat, we can designate critical habitat in areas outside the geographical area occupied by the species at the time it is listed, upon a determination that such areas are essential for the conservation of the species. For example, an area currently occupied by the species but that was not occupied at the time of listing may be essential to the conservation of the species and may be included in the critical habitat designation. We designate critical habitat in areas outside the geographical area occupied by a species only when a designation limited to its range would be inadequate to ensure the conservation of the species. Section 4 of the Act requires that we designate critical habitat on the basis of the best scientific and commercial data available. Further, our Policy on Information Standards under the Endangered Species Act (published in the Federal Register on July 1, 1994 (59 FR 34271)), the Information Quality Act (section 515 of the Treasury and General Government Appropriations Act for Fiscal Year 2001 (Pub. L. 106-554; H.R. 5658)), and our associated Information Quality Guidelines, provide criteria, establish procedures, and provide guidance to ensure that our decisions are based on the best scientific data available. They require our biologists, to the extent consistent with the Act and with the use of the best scientific data available, to use primary and original sources of information as the basis for recommendations to designate critical habitat. When we are determining which areas should be designated as critical habitat, our primary source of information is generally the information developed during the listing process for the species. Additional information sources may include articles in peer-reviewed journals, conservation plans developed by States and counties, scientific status surveys and studies, biological assessments, or other unpublished materials and expert opinion or personal knowledge. Habitat is dynamic, and species may move from one area to another over time. We recognize that critical habitat designated at a particular point in time may not include all of the habitat areas that we may later determine are necessary for the recovery of the species. For these reasons, a critical habitat designation does not signal that habitat outside the designated area is unimportant or may not be needed for recovery of the species. Areas that are important to the conservation of the species, both inside and outside the critical habitat designation, will continue to be subject to: (1) Conservation actions implemented under section 7(a)(1) of the Act, (2) regulatory protections afforded by the requirement in section 7(a)(2) of the Act for Federal agencies to insure their actions are not likely to jeopardize the continued existence of any endangered or threatened species, and (3) section 9 of the Act's prohibitions on taking any individual or the species, including taking caused by actions that affect habitat. Federally funded or permitted projects affecting listed species outside their designated critical habitat areas may still result in jeopardy findings in some cases. These protections and conservation tools will continue to contribute to recovery of these species. Similarly, critical habitat designations made on the basis of the best available information at the time of designation will not control the direction and substance of future recovery plans, habitat conservation plans (HCPs), or other species conservation planning efforts if new information available at the time of these planning efforts calls for a different outcome. Physical and Biological Features In accordance with sections 3(5)(A)(i) and 4(b)(1)(A) of the Act and the regulations at 50 CFR 424.12, in determining which areas within the geographical area occupied at the time of listing to propose as critical habitat, we consider the physical and biological features (PBFs) essential to the conservation of the species that may require special management considerations or protection. These may include, but are not limited to: (1) Space for individual and population growth and for normal behavior; (2) Food, water, air, light, minerals, or other nutritional or physiological requirements; (3) Cover or shelter; (4) Sites for breeding, reproduction, or rearing (or development) of offspring; and (5) Habitats that are protected from disturbance or are representative of the historical, geographical, and ecological distributions of a species. We derive the specific PBFs required for the fluted kidneyshell and slabside pearlymussel based on their biological needs. Little is known of the specific habitat requirements of these two mussel species other than they require flowing water, stable stream channels, adequate water quality, and fish hosts for development of larva to metamorphose into juvenile mussels. To identify the physical and biological needs of the species, we have relied on current conditions at locations where the species survive, the limited information available on these two mussels and their close relatives, and factors associated with the decline and extirpation of these and other mussels from portions of the Cumberland and Tennessee River systems. Additional information is located in the final listing rule, which can be found elsewhere in today's Federal Register . We have determined that the fluted kidneyshell and slabside pearlymussel require the following physical or biological features: Space for Individual and Population Growth and for Normal Behavior The fluted kidneyshell and slabside pearlymussel are historically associated with the Cumberland and Tennessee River drainages in Alabama, Kentucky, Mississippi, Tennessee, and Virginia. Mussels generally live embedded in the bottom of stable streams and other bodies of water, and within riffle areas of sufficient current velocities to remove finer sediments and provide well-oxygenated waters. The fluted kidneyshell is primarily a medium-sized creek to large river species, inhabiting sand and gravel substrates in relatively shallow riffles and shoals with moderate to swift current (Parmalee and Bogan 1998, p. 205). In comparison to co-occurring species, the fluted kidneyshell demonstrates strong habitat specificity. It is associated with faster flows, greater baseflow shear stress, and low substrate embeddedness (Ostby 2005, pp. 51, 142-143). The slabside pearlymussel is primarily a large creek to large river species, inhabiting sand, fine gravel, and cobble substrates in relatively shallow riffles and shoals with moderate current (Parmalee and Bogan 1998, p. 152). Similar to other mussels, fluted kidneyshell and slabside pearlymussel are dependent on areas with flow refuges where shear stress is relatively low, although the fluted kidneyshell is more tolerant of shear stress than other species (Layzer and Madison 1995, p. 341; Strayer 1999, pp. 468 and 472; Hastie et al. 2001, pp. 111-114). Flow refuges conceivably allow relatively immobile mussels such as the fluted kidneyshell and slabside pearlymussel to remain in the same general location throughout their entire lives. Natural river or creek channel stability is achieved by allowing the river or creek to develop a stable dimension, pattern, and profile such that, over time, channel features are maintained and the river or creek system neither aggrades nor degrades. Channel instability occurs when the scouring process leads to degradation or excessive sediment deposition results in aggradation. Stable rivers and creeks consistently transport their sediment load, both in size and type, associated with local deposition and scour (Rosgen 1996, p. 1-3). Sedimentation has been determined to be a major factor in habitat destruction, resulting in corresponding shifts in mussel fauna (Brim Box and Mossa 1999, p. 102). Stable stream bottom substrates not only provide space for populations of these mussel species, but also provide cover and shelter and sites for breeding, reproduction, and growth of offspring. Habitat conditions described in the previous paragraphs provide space, cover, shelter, and sites for breeding, reproduction, and growth of offspring for the fluted kidneyshell and slabside pearlymussel. These habitats are dynamic and are formed and maintained by water quantity, channel features (dimension, pattern, and profile), and sediment input to the system through periodic flooding, which maintain connectivity and interaction with the flood plain. Changes in one or more of these parameters can result in channel degradation or aggradation, with serious effects to mussels. Therefore, based on the information above, we identify riffles of large creeks and rivers with sand, gravel, and cobble substrates; areas of moderate to high amount of flow, but with refugia of low shear stress; stream channel stability; and floodplain connectivity to be PBFs for both of these species. Food, Water, Air, Light, Minerals, or Other Nutritional or Physiological Requirements Mussels, such as these two species, siphon water into their shells and across four gills that are specialized for respiration, food collection, and brooding larvae in females. Food items include detritus (disintegrated organic debris), algae, diatoms, and bacteria (Strayer et al. 2004, pp. 430-431). Encysted glochidia are nourished by their fish hosts and feed for a period of one week to several months. Nutrient uptake by glochidia is not well understood, but probably occurs through the microvillae of the mantle, an umbilical cord-like structure that is used to extract nutrients as glochidia are attached to gill filiments of host fish. For the first several months, the gills of juvenile mussels are rudimentary and generally incapable of filtering particles (Watters 2007, p. 56). To extract bacteria, algae, and detritus from the sediment, juvenile mussels partially employ pedal (foot) feeding and may filter interstitial (pore) water (Yeager et al. 1994, pp. 217-221). Adult mussels primarily filter feed from the ambient water column, but can also obtain their food by deposit feeding, pulling in food from the sediment and its interstitial water and pedal feeding directly from the sediment (Yeager et al. 1994, pp. 217-221; Vaughn and Hakenkamp 2001, pp. 1432-1438). Food availability and quality for the fluted kidneyshell and slabside pearlymussel in their habitats are affected by habitat stability, floodplain connectivity, flow, and water and sediment quality. Excessive sedimentation has been shown to impair the filter feeding ability of mussels. When in high silt environments, mussels may keep their valves closed more often, resulting in reduced feeding activity (Ellis 1936, p. 30), and high amounts of suspended sediments can dilute their food source (Dennis 1984, p. 212). Adequate food availability and quality is essential for normal behavior, growth, and viability during all life stages of these two species. Excessive sedimentation often results in fine silt particles culminating within interstitial spaces, embedding and even concretizing the substrate and virtually altering habitat to such a degree that it becomes uninhabitable for mussels, particularly juveniles. Excessive suspended sediments may also impair visual acuity of host fish, an obstacle to the mechanisms that mussels employ to attract and inoculate host fish with glochidia. The fluted kidneyshell and slabside pearlymussel are riverine species that depend upon adequate water flow. Continuously flowing water is a habitat feature associated with both of these species. Flowing water maintains the stream bottom habitats where these species are found, transports food items to the sedentary juvenile and adult life stages, removes wastes, and provides oxygen for respiration. A natural flow regime that includes periodic flooding and maintains connectivity and interaction with the floodplain is critical for the exchange of nutrients, movement of and spawning activities for potential fish hosts, and maintenance of flow refuges in riffle and run habitats. Further, riffle areas are often defined by an abundance and diversity of organisms that likely have dependent and competitive interactions yet unknown, but that are important for riffle-dwelling mussel species such as the fluted kidneyshell and slabside pearlymussel. The ranges of standard physical and chemical water quality parameters (such as temperature, dissolved oxygen, pH, and conductivity) that define suitable habitat conditions for the two species are poorly understood and have not been fully investigated. However, as relatively sedentary animals, mussels must be able to tolerate the full range of such parameters that occur naturally within the streams where they persist, or they will either be biologically compromised such that feeding, breeding, or sheltering activities are affected or mortality occurs. Environmental contamination degrades water quality parameters to a level that negatively affects a mussel's biological functions and is a causal (contributing) factor in the decline of mussel populations. Most numeric standards for pollutants and water quality parameters (for example, dissolved oxygen, pH, and heavy metals) that have been adopted by the States under the Clean Water Act (CWA; 33 U.S.C. 1251 et seq. ) represent levels that are essential to the conservation of both mussels. The Service is currently in consultation with the Environmental Protection Agency (EPA) to evaluate the protectiveness of criteria approved in EPA's water quality standards for endangered and threatened species and their critical habitats as described in the memorandum of agreement that our agencies signed in 2001 (66 FR 11201; February 22, 2001). Other factors that can potentially alter water quality are droughts and periods of low flow, water withdrawals, nonpoint source runoff from adjacent land surfaces (for example, excessive amounts of sediments, nutrients, and pesticides), point source discharges from municipal and industrial wastewater treatment facilities (for example, excessive amounts of ammonia, chlorine, and metals), thermal and flow modifications resulting from hydropower generation, and random spills or unregulated discharge events. These factors can be particularly harmful to mussels during drought conditions because water flows are depressed and pollutants are more concentrated. Both water quantity and quality where both species currently exist vary widely according to season, precipitation events, and seasonal human activities within the watershed. Conditions across the mussels' historical ranges vary even more due to watershed size, geology, geography, and differences in human population densities and land uses. In general, both of the species survive in areas where the magnitude, frequency, duration, and seasonality of water flow are adequate to maintain stable habitats (for example, sufficient flow to remove fine particles and sediments without causing degradation), and where water quality is adequate for year-round survival (for example, moderate to high levels of dissolved oxygen, low to moderate input of nutrients, and relatively unpolluted water and sediments). Therefore, based on the information above, we identify adequate food items for all life stages, sufficient water flow, and adequate water quality to be PBFs for both of these species. Sites for Breeding, Reproduction, or Rearing Mussels require a host fish for transformation of larval mussels (glochidia) to juvenile mussels (Williams et al. 2008, p. 68). Thus, the presence of the appropriate host fishes to complete the reproductive life cycle is essential to the conservation of these two mussels. The known host fishes of the fluted kidneyshell include: barcheek darter ( Etheostoma obeyense ), fantail darter ( E. flabellare ), rainbow darter ( E. caeruleum ), redline darter ( E. rufilineatum ), bluebreast darter ( E. camurum ), dusky darter ( Percina sciera ), and banded sculpin ( Cottus carolinae ). The known host fishes of the slabside pearlymussel include: popeye shiner ( Notropis ariommus ), rosyface shiner ( N. rubellus ), saffron shiner ( N. rubricroceus ), silver shiner ( N. photogenis ), telescope shiner ( N. telescopus ), Tennessee shiner ( N. leuciodus ), whitetail shiner ( Cyprinella galactura ), striped shiner ( Luxilus chrysocephalus ), warpaint shiner ( L. coccogenis ), white shiner ( L. albeolus ), and eastern blacknose dace ( Rhinichthys atratulus ). There are likely other suitable host fishes that have not yet been studied or confirmed. Fluted kidneyshell and slabside pearlymussel juveniles require stable habitats with adequate water quantity and quality as previously described for growth and survival. Excessive sediments or dense growth of filamentous algae can expose juvenile mussels to entrainment or predation and be detrimental to the survival of juvenile mussels (Hartfield and Hartfield 1996, pp. 372-374). Geomorphic instability can result in the loss of interstitial habitats and juvenile mussels due to scouring or deposition (Hartfield 1993, pp. 372-373). Water quality, sediment quality, stable habitat, health of fish hosts, and diet (of all life stages) all influence survival of each life stage and subsequent reproduction and recruitment (Cope et al. 2008, p. 452). Floodplain connectivity is important to dissipate hydrolic energy during periodic flooding. Also connection to the floodplain provides habitats during wet years for spawning and foraging activities for fish hosts that require floodplain habitats for successful reproduction and recruitment to adulthood. Barko et al. (2006, pp. 252-256) found that several fish host or potential host species (none of which is a documented host for the fluted kidneyshell or slabside pearlymussel) benefited from the ability to exploit floodplain habitat resources that were not typically available for use during years of normal flows. Furthermore, Kwak (1988, pp. 243-247) and Slipke and Maceina (2005, p. 289) indicated that periodic inundation of floodplain habitats increased successful fish reproduction, which leads to increased availability of native host fishes for mussel reproduction. However, Rypel et al. (2009, p. 502) indicated that mussels tended to exhibit minimal growth during high flow years. Therefore, optimal flooding of these habitats would not be too frequent and may need to occur at similar frequencies to that of the natural hydrologic regime of the rivers and creeks inhabited by the fluted kidneyshell and slabside pearlymussel. Natural temperature regimes can be altered by impoundments, water releases from dams, industrial and municipal effluents, and changes in riparian habitat. Critical thermal limits for survival and normal functioning of many mussel species and host fish are unknown. High temperatures can reduce dissolved oxygen concentrations in the water, which slows growth, reduces glycogen stores, impairs respiration, and may inhibit reproduction (Hart and Fuller 1974, pp. 240-241). Low temperatures can significantly delay or prevent metamorphosis (Watters and O'Dee 1999, pp. 454-455). Water temperature increases have been documented to shorten the period of glochidial encystment, increase oxygen consumption, reduce the speed in which they orient themselves in the substrate, and slow burrowing and movement responses (Hart and Fuller 1974, pp. 240-241; Bartsch et al. 2000, p. 237; Watters et al. 2001, p. 546; Schwalb and Pusch 2007, pp. 264-265). Several studies have documented the influence of temperature on the timing of aspects of mussel reproduction (e.g., Gray et al. 2002, p. 156; Allen et al. 2007, p. 85; Steingraeber et al. 2007, pp. 303-309). Peak glochidial releases are associated with water temperature thresholds that can be thermal minimums or maximums, depending on the species (Watters and O'Dee 2000, p. 136). Abnormal temperature changes may cause particular problems to mussels whose reproductive cycles may be linked to fish reproductive cycles (e.g., Young and Williams 1984, entire). Therefore, based on the information above, we identify presence of appropriate fish hosts, water quality, sediment quality, stable habitat, food for all life stages, periodic flooding of and connectivity to floodplain habitat, and a natural temperature regime to be PBFs for both of these species. Primary Constituent Elements for the Fluted Kidneyshell and Slabside Pearlymussel Under the Act and its implementing regulations, we are required to identify the PBFs essential to the conservation of these mussel species in areas occupied at the time of listing, focusing on the features' primary constituent elements (PCEs). We consider PCEs to be the specific elements of PBFs that provide for a species' life-history processes and are essential to the conservation of the species. Based on the above needs and our current knowledge of the life history, biology, and ecology of the species and the habitat requirements for sustaining the essential life-history functions of the species, we have determined that the PCEs for the fluted kidneyshell are: (1) Riffle habitats within large, geomorphically stable stream channels (channels that maintain lateral dimensions, longitudinal profiles, and sinuosity patterns over time without an aggrading or degrading bed elevation). (2) Stable substrates of sand, gravel, and cobble with low to moderate amounts of fine sediment and containing flow refugia with low shear stress. (3) A natural hydrologic flow regime (the magnitude, frequency, duration, and seasonality of discharge over time) necessary to maintain benthic habitats where the species are found, and connectivity of rivers with the floodplain, allowing the exchange of nutrients and sediment for habitat maintenance, food availability for all life stages, and spawning habitat for native fishes. (4) Water quality with low levels of pollutants and including a natural temperature regime, pH (between 6.0 to 8.5), oxygen content (not less than 5.0 milligrams per liter (mg/L)), hardness, and turbidity necessary for normal behavior, growth, and viability of all life stages. (5) The presence of abundant fish hosts, which may include the barcheek darter, fantail darter, rainbow darter, redline darter, bluebreast darter, dusky darter and banded sculpin, necessary for recruitment of the fluted kidneyshell. Based on the above needs and our current knowledge of the life history, biology, and ecology of the species and the habitat requirements for sustaining the essential life-history functions of the species, we have determined that the PCEs for the slabside pearly mussel are: (1) Riffle habitats within large, geomorphically stable stream channels (channels that maintain lateral dimensions, longitudinal profiles, and sinuosity patterns over time without an aggrading or degrading bed elevation). (2) Stable substrates of sand, gravel, and cobble with low to moderate amounts of fine sediment and containing flow refugia with low shear stress. (3) A natural hydrologic flow regime (magnitude, frequency, duration, and seasonality of discharge over time) necessary to maintain benthic habitats where the species is found, and connectivity of rivers with the floodplain, allowing the exchange of nutrients and sediment for habitat maintenance, food availability for all life stages, and spawning habitat for native fishes. (4) Water quality with low levels of pollutants and including a natural temperature regime, pH (between 6.0 to 8.5), oxygen content (not less than 5.0 milligrams/liter), hardness, and turbidity necessary for normal behavior, growth, and viability of all life stages. (5) The presence of abundant fish hosts, which may include the popeye shiner, rosyface shiner, saffron shiner, silver shiner, telescope shiner, Tennessee shiner, whitetail shiner, white shiner, and eastern blacknose dace, necessary for recruitment of the slabside pearlymussel. Special Management Considerations or Protection When designating critical habitat, we assess whether the specific areas within the geographical area occupied by the species at the time of listing contain features which are essential to the conservation of the species and that may require special management considerations or protection. The 30 occupied units we are designating as critical habitat for the fluted kidneyshell (17) and the slabside pearlymussel (13), 10 of which overlap but are counted as separate critical habitat units for each species, will require some level of management to address the current and future threats to the PBFs of the species. Habitat loss and degradation negatively impact the fluted kidneyshell and slabside pearlymussel. Severe degradation from impoundments, gravel and coal mining, oil and natural gas development, sedimentation, chemical contaminants, and stream channel alterations threaten the stream habitat and water quality on which these species depend. Contaminants associated with coal mining (metals, other dissolved solids), municipal effluents (bacteria, nutrients, pharmaceuticals), and agriculture (fertilizers, pesticides, herbicides, and animal waste) cause degradation of water quality and habitats through increased acidity and conductivity, instream oxygen deficiencies, excess nutrification, and excessive algal growths. The CWA has been insufficient to significantly reduce or remove these threats to the fluted kidneyshell and slabside pearlymussel. Other natural and manmade factors, such as alteration of natural temperature regimes below dams; chemical contaminants; sedimentation; small, isolated populations; and low genetic diversity, combined with localized extinctions from point source pollution or accidental toxic chemical spills, habitat modification and progressive degradation by nonpoint source pollutants, natural catastrophic changes to habitat through flood scour or drought as exacerbated by climate change, and nonindigenous species are threats to remaining populations of the fluted kidneyshell and slabside pearlymussel. Of the 30 total occupied units, a portion of 6 units are located on the Daniel Boone National Forest (DBNF), 14 are almost entirely on private land, 1 is located on the Big South Fork National River and Recreational Area (BSFNRRA), 1 is located on the Cherokee National Forest (CNF), and 8 units have mixed ownership with private, State park, and national wildlife refuge lands. Four of the occupied units have been designated as mussel sanctuaries by the TWRA. Portions of six critical habitat units on DBNF land are being managed and protected under DBNF's Land and Resource Management Plan (LRMP), and the Hiwassee River unit is protected under CNF's LRMP (United States Forest Service (USFS) 2004a, pp. 1-14; 2004b, entire). The LRMPs are implemented through a series of project-level decisions based on appropriate site-specific analysis and disclosure. The LRMPs do not contain a commitment to select any specific project; rather, they set up a framework of desired future conditions with goals, objectives, and standards to guide project proposals. Projects are proposed to solve resource management problems, move the forest environment toward desired future conditions, and supply goods and services to the public (USFS 2004a, pp. 1-14). The LRMPs contain a number of protective standards that in general are designed to avoid and minimize potential adverse effects to the fluted kidneyshell, slabside pearlymussel, and other federally listed species; however, the DBNF and CNF will continue to conduct project-specific section 7 consultations under the Act when their activities may adversely affect the fluted kidneyshell, slabside pearlymussel, and other federally listed species or adversely modify their designated critical habitats. Fourteen of the 30 occupied critical habitat units are located almost entirely on private property and are not presently under the special management or protection provided by a legally operative plan or agreement for the conservation of the species. One of the 30 occupied critical habitat units (Big South Fork Cumberland River) is located almost entirely on Federal lands within the BSFNRRA. Land and resource management decisions and activities within the BSFNRRA are guided by the National Park Service General Management Plan, Field Management Plan, and Draft Non-Federal Oil and Gas Management Plan (NPS 2005, entire; NPS 2006, pp. 1-12; NPS 2011, entire). Eight of the 30 occupied critical habitat units (Clinch and Duck Rivers) have mixed ownership with private, State park, and national wildlife refuge lands. These lands are operated under various plans that may or may not provide the special management or protection provided by a legally operative plan or agreement for the conservation of these species. Portions of four of the occupied critical habitat units (Powell, Clinch, Hiwassee, and Duck Rivers) have been designated as mussel sanctuaries by TWRA. The collection of mollusks and the degradation or destruction of aquatic habitats in these areas is prohibited at all times. Various activities in or adjacent to each of the occupied critical habitat units described in this final rule may affect one or more of the PBFs. Some of these activities include, but are not limited to, those discussed in the Summary of Factors Affecting the Species in the final listing rule found elsewhere in today's Federal Register (e.g., impoundments, gravel and coal mining, water pollution, invasive species; see Factors A, D, and E ). Other activities that may affect PBFs in the final critical habitat units include those listed in Available Conservation Measures (see final listing rule). Special management considerations or protection will conserve the PBFs for these species. Management activities that could ameliorate threats on both Federal and non-Federal lands include, but are not limited to: Use of best management practices (BMPs) designed to reduce sedimentation, erosion, and stream bank alteration; moderation of surface and ground water withdrawals to maintain natural flow regimes; increase of stormwater management and reduction of stormwater flows into the systems; preservation of headwater streams; regulation of off-road vehicle use; and reduction of other watershed and floodplain disturbances that release sediments, pollutants, or nutrients into the water. In summary, we find that the areas we are designating as occupied critical habitat for the fluted kidneyshell and slabside pearlymussel contain the PBFs necessary for the species, and that these features may require special management considerations or protection. Special management consideration or protection may be required to eliminate, or to reduce to negligible levels, the threats affecting the PBFs of each unit. Additional discussion of threats facing individual units is provided in the individual unit descriptions below. Criteria Used To Identify Critical Habitat As required by section 4(b) of the Act, we used the best scientific and commercial data available to designate critical habitat for both the fluted kidneyshell and slabside pearlymussel. In accordance with the Act and its implementing regulations at 50 CFR 424.12(e), we also consider whether designating additional areas outside those currently occupied as well as those occupied at the time of listing is necessary to ensure the conservation of these species. We are designating critical habitat in areas within the geographic area currently occupied by the species. We also are designating specific areas outside the geographic area currently occupied by the species, which were historically occupied but are presently unoccupied, because such areas are essential for the conservation of the species. We began our analysis by considering historical and current ranges of both species. We used various sources including published literature and museum collection databases, as well as surveys, reports, and field notes prepared by biologists. We then identified the specific areas that are occupied by both mussels and that contain one or more of the PBFs. We defined occupied habitat as those stream reaches known to be currently occupied by either of the two species. To identify the currently occupied stream reaches, we used post-1980 survey data. To identify the unoccupied stream reaches, we used survey data between the late 1800s and 1979. Therefore, if a species was known to occur in an area prior to 1980, but was not collected since then, the stream reach is considered unoccupied. This criterion was chosen because a large number of collections were conducted in the 1980s in the Cumberland and Tennessee River systems. Some of the historical occurrences have not been surveyed since the 1980s. However, because of the longevity of these species (26-55 years) and the presence of fish hosts, they are still thought to occur in these areas. We then evaluated occupied stream reaches to delineate the probable upstream and downstream extent of each species' distribution. Known occurrences for some mussel species are extremely localized, and rare mussels can be difficult to locate. In addition, stream habitats are highly dependent upon upstream and downstream channel habitat conditions for their maintenance. Therefore, where more than one occurrence record of a particular species was found within a stream reach, we considered the entire reach between the uppermost and lowermost locations as occupied habitat. We then considered whether this essential area was adequate for the conservation of both species. Small, isolated, aquatic populations are subject to chance catastrophic events and to changes in human activities and land use practices that may result in their elimination. Larger, more contiguous populations can reduce the threat of extinction due to habitat fragmentation and isolation. For these reasons, conservation of the fluted kidneyshell, but not the slabside pearlymussel, requires expanding its range into currently unoccupied portions of its historical habitat. Given that threats to the fluted kidneyshell are compounded by its limited distribution and isolation, it is unlikely that currently occupied habitat is adequate for its conservation. The range of the fluted kidneyshell has been severely curtailed, occupied habitats are limited and isolated, and population sizes are generally small (see Summary of Factors Affecting the Species, which can be found in the final listing rule published elsewhere in today's Federal Register ). For example, the fluted kidneyshell is no longer believed to occur in the Rockcastle, Hiwassee, Elk, Holston, French Broad, or Buffalo Rivers. The inclusion of essential unoccupied areas will provide habitat for population reintroduction and will decrease the risk of extinction. Based on the best scientific data available, these areas not currently occupied by the fluted kidneyshell are essential for their conservation. We eliminated from consideration as unoccupied critical habitat the Red and Harpeth River drainages; the Caney Fork, mainstem Cumberland, mainstem Tennessee, Tellico, Obey, South Fork Powell, South Fork Holston, West Prong Little Pigeon, Little Tennessee Rivers; and Kennedy, Pittman, Otter, Flint, Sugar, Limestone, Shoal, Puckell, North Fork, and Big Rock Creeks for both of these mussels. These areas are not essential for the conservation of the mussels because of stream channel alterations, a limited amount of available habitat coupled with isolation from other populations, a lack of a native mussel fauna, poor habitat or water quality, or a lack of available fish hosts. All of the stream habitat areas designated as unoccupied critical habitat have sufficient water quality and fish hosts necessary for the fluted kidneyshell. The stream reaches also lack major anthropogenic disturbances and have potential for reoccupation by the species through future reintroduction efforts. Based on the above factors, all unoccupied stream reaches included in the designation for the fluted kidneyshell are essential for its conservation. In our analysis (see above paragraph), we did not find suitable habitat, water quality, or fish hosts present in areas historically inhabited by but presently unoccupied by the slabside pearlymussel. Therefore, we did not find any unoccupied stream reaches to be essential to the conservation of the slabside pearlymussel. Following the identification of occupied and unoccupied stream reaches, the next step was to delineate the probable upstream and downstream extent of each species' distribution. We used USGS 1:100,000 digital stream maps to delineate these boundaries of designated critical habitat units according to the criteria explained below. The upstream boundary of a unit in a stream is the first perennial, named tributary confluence, a road-crossing bridge, or a permanent barrier to fish passage (such as a dam) above the upstream-most current occurrence record. The confluence of a tributary typically marks a significant change in the size of the stream and is a logical and recognizable upstream terminus. When a named tributary was not available, a road-crossing bridge was used to mark the boundary. Likewise, a dam or other barrier to fish passage marks the upstream extent to which mussels may disperse via their fish hosts. The downstream boundary of a unit in a stream is the confluence of a named tributary, or the upstream extent of an impoundment, below the downstream-most occurrence record. In the unit descriptions, distances between landmarks marking the upstream or downstream extent of a stream segment are given in river kilometers and equivalent miles, as measured tracing the course of the stream, not straight-line distance. Because mussels are naturally restricted by certain physical conditions within a stream reach (i.e., flow, substrate), they may be unevenly distributed within these habitat units. Uncertainty on upstream and downstream distributional limits of some populations may have resulted in small areas of occupied habitat excluded from, or areas of unoccupied habitat included in, the designation. We recognize that both historical and recent collection records upon which we relied are incomplete, and that there may be river segments or small tributaries not included in this designation that harbor small, limited populations of one or both species considered in this designation, or that others may become suitable in the future. The exclusion of such areas does not diminish their potential individual or cumulative importance to the conservation of these species. However, with proper management, each of the critical habitat units (24 fluted kidneyshell units, and 13 slabside pearlymussel units; 10 overlap between the two species) are capable of supporting one or both of these mussel species, and that populations within occupied units will serve as source populations for artificial reintroduction into unoccupied units, as well as assisted or natural migration into adjacent undesignated or designated streams within each river drainage. The habitat areas contained within the units described below constitute our best evaluation of areas needed for the conservation of these species at this time. Critical habitat may be revised for any or all of these species should new information become available. The areas designated as critical habitat below include only stream channels within the ordinary high-water line and do not contain developed areas or structures. The scale of the maps we prepared under the parameters for publication within the Code of Federal Regulations may not reflect the exclusion of such developed lands. Any such lands inadvertently left inside critical habitat boundaries shown on the maps of this final rule have been excluded by text in the rule and are not designated as critical habitat. Therefore, a Federal action involving these lands would not trigger section 7 consultation with respect to critical habitat and the requirement of no adverse modification unless the specific action would affect the PBFs in the adjacent critical habitat. The critical habitat designation is defined by the map or maps, as modified by any accompanying regulatory text, presented at the end of this document. We include more detailed information on the boundaries of the critical habitat designation in the preamble of this document. We will make the coordinates or plot points or both on which each map is based available to the public on http://www.regulations.gov at Docket No. FWS-R4-ES-2013-0026, on our Internet site at http://www.fws.gov/cookeville, and at the Fish and Wildlife office responsible for the designation (see FOR FURTHER INFORMATION CONTACT above). Final Critical Habitat Designation We are designating approximately 2,218 rkm (1,380 rmi) in Alabama, Kentucky, Mississippi, Tennessee, and Virginia as critical habitat. For the fluted kidneyshell, we are designating 24 critical habitat units encompassing approximately 1,899 rkm (1,181 rmi) of stream channel in Alabama, Kentucky, Tennessee, and Virginia. The critical habitat areas we describe below constitute our current best assessment of areas that meet the definition of critical habitat for the fluted kidneyshell. The 24 areas we designate as critical habitat are as follows: (1) Horse Lick Creek, KY; (2) Middle Fork Rockcastle River, KY; (3) Rockcastle River, KY; (4) Buck Creek, KY; (5) Rock Creek, KY; (6) Little South Fork Cumberland River, KY; (7) Big South Fork Cumberland River, KY, TN; (8) Wolf River and Town Branch, TN; (9) West Fork Obey River, TN; (10) Indian Creek, VA; (11) Little River [tributary to the Clinch River], VA; (12) North Fork Holston River, VA; (13) Middle Fork Holston River, VA; (14) Big Moccasin Creek, VA; (15) Copper Creek, VA; (16) Clinch River, TN, VA; (17) Powell River, TN, VA; (18) Nolichucky River, TN; (19) Holston River, TN; (20) French Broad River, TN; (21) Hiwassee River, TN; (22) Elk River, AL, TN; (23) Duck River, TN; and (24) Buffalo River, TN. We are designating 13 critical habitat units encompassing approximately 1,562 rkm (970 rmi) of stream channel in Alabama, Mississippi, Tennessee, and Virginia for the slabside pearlymussel. The critical habitat areas we describe below constitute our current best assessment of areas that meet the definition of critical habitat for the slabside pearlymussel. The 13 areas we designate as critical habitat are as follows: (1) North Fork Holston River, VA; (2) Middle Fork Holston River, VA; (3) Big Moccasin Creek, VA; (4) Clinch River, TN, VA; (5) Powell River, TN, VA; (6) Nolichucky River, TN; (7) Hiwassee River, TN; (8) Sequatchie River, TN; (9) Paint Rock River, AL; (10) Elk River, AL, TN; (11) Bear Creek, AL, MS; (12) Duck River, TN; and (13) Buffalo River, TN. Note that 10 of the units overlap and are designated as critical habitat for both species (each overlapping unit is counted twice, once for each species): Unit FK12 and SP1 (North Fork Holston River, Virginia), Unit FK13 and SP2 (Middle Fork Holston River, Virginia), Unit FK14 and SP3 (Big Moccasin Creek, Virginia), Unit FK16 and SP4 (Clinch River, Tennessee and Virginia), Unit FK17 and SP5 (Powell River, Tennessee and Virginia), Unit FK18 and SP6 (Nolichucky River, Tennessee), Unit FK21 and SP7 (Hiwassee River, Tennessee), Unit FK22 and SP10 (Elk River, Alabama and Tennessee), Unit FK23 and SP12 (Duck River, Tennessee), and Unit FK24 and SP13 (Buffalo River, Tennessee). Unit name, location, and the approximate stream length of each designated critical habitat unit are shown in Table 1 for the fluted kidneyshell and Table 2 for the slabside pearlymussel. The designated critical habitat units include the stream channels within the ordinary high-water line only. For this purpose, we have applied the definition found at 33 CFR 329.11, and consider the ordinary high-water mark on nontidal rivers to be the line on the shore established by the fluctuations of water and indicated by physical characteristics, such as a clear, natural line impressed on the bank; shelving; changes in the character of soil; destruction of terrestrial vegetation; the presence of litter and debris; or other appropriate means that consider the characteristics of the surrounding areas. States were granted ownership of lands beneath navigable waters up to the ordinary high-water line upon achieving Statehood ( Pollard v. Hagan, 44 U.S. (3 How.) 212 (1845)). Prior sovereigns or the States may have made grants to private parties that included lands below the ordinary high-water mark of some navigable waters that are included in this final rule. Most, if not all, lands beneath the navigable waters included in this rule are owned by the States. The lands beneath most nonnavigable waters included in this rule are in private ownership. In Alabama, the riparian landowner owns the stream to the middle of the channel for non-navigable streams. Riparian lands along the waters are either in private ownership, or are owned by county, State, or Federal entities. Lands under county, State, and Federal ownership consist of managed conservation areas and are considered to have some level of protection. Table 1—Occupancy and Ownership of Riparian Lands Adjacent to the Designated Critical Habitat Units for the Fluted Kidneyshell Unit Location Occupied by species Private ownership rkm (rmi) Federal, State, County, City ownership rkm (rmi) Total length rkm (rmi) FK1 Horse Lick Creek, KY Yes 3.6 (2.3) 15.8 (10.1) 19.4 (12.4) FK2 Middle Fork Rockcastle River, KY Yes 6.0 (3.7) 6.5 (4.0) 12.5 (7.7) FK3 Rockcastle River, KY No 11.7 (7.3) 58.2 (36.2) 69.9 (43.5) FK4 Buck Creek, KY Yes 59.7 (37.1) 1.3 (0.8) 61.0 (37.9) FK5 Rock Creek, KY Yes 1.5 (0.9) 17.7 (11.0) 19.2 (11.9) FK6 Little South Fork Cumberland River, KY Yes 61.1 (38.0) 4.4 (2.7) 65.5 (40.7) FK7 Big South Fork Cumberland River, KY, TN Yes 1.5 (1.0) 90.0 (55.9) 91.5 (56.9) FK8 Wolf River and Town Branch, TN Yes 38.7 (24.0) 5.7 (3.5) 44.4 (27.5) FK9 West Fork Obey River, TN Yes 19.3 (12.0) 0 19.3 (12.0) FK10 Indian Creek, VA Yes 6.7 (4.2) 0 6.7 (4.2) FK11 Little River, VA Yes 50.4 (31.3) 0 50.4 (31.3) FK12 North Fork Holston River, VA Yes 66.4 (41.3) 0.9 (0.5) 67.3 (41.8) FK13 Middle Fork Holston River, VA Yes 89.0 (55.3) 0 89.0 (55.3) FK14 Big Moccasin Creek, VA No 33.1 (20.6) 0 33.1 (20.6) FK15 Copper Creek, VA Yes 55.5 (34.5) 0 55.5 (34.5) FK16 Clinch River, TN, VA Yes 256.3 (159.2) 6.4 (4.0) 262.7 (163.2) FK17 Powell River, TN, VA Yes 152.4 (94.7) 0.3 (0.2) 152.7 (94.9) FK18 Nolichucky River, TN Yes 50.9 (31.6) 0.9 (0.6) 51.9 (32.2) FK19 Holston River, TN No 85.1 (52.9) 0 85.1 (52.9) FK20 French Broad River, TN No 54.4 (33.8) 1.7 (1.1) 56.1 (34.9) FK21 Hiwassee River, TN No 0 24.4 (15.2) 24.4 (15.2) FK22 Elk River, AL, TN No 162.8 (101.2) 1.5 (0.9) 164.3 (102.1) FK23 Duck River, TN Yes 284.0 (176.5) 63.5 (39.4) 347.5 (215.9) FK24 Buffalo River, TN No 50.0 (31.0) 0 50.0 (31.0) Total 1,899.4 (1,180.5) Table 2—Occupancy and Ownership of Riparian Lands Adjacent to the Designated Critical Habitat Units for the Slabside Pearlymussel Unit Location Occupied Private ownership rkm (rmi) Federal, State, County, City ownership rkm (rmi) Total length rkm (rmi) SP1 North Fork Holston River, VA Yes 66.4 (41.3) 0.9 (0.5) 67.3 (41.8) SP2 Middle Fork Holston River, VA Yes 89.0 (55.3) 0 89.0 (55.3) SP3 Big Moccasin Creek, VA Yes 33.1 (20.6) 0 33.1 (20.6) SP4 Clinch River, TN, VA Yes 256.3 (159.2) 6.4 (4.0) 262.7 (163.2) SP5 Powell River, TN, VA Yes 152.4 (94.7) 0.3 (0.2) 152.7 (94.9) SP6 Nolichucky River, TN Yes 50.9 (31.6) 0.9 (0.6) 51.9 (32.2) SP7 Hiwassee River, TN Yes 0 24.4 (15.2) 24.4 (15.2) SP8 Sequatchie River, TN Yes 151.5 (94.1) 0 151.5 (94.1) SP9 Paint Rock River, AL Yes 119.2 (74.1) 5.8 (3.6) 125.0 (77.7) SP10 Elk River, AL, TN Yes 162.8 (101.2) 1.5 (0.9) 164.3 (102.1) SP11 Bear Creek, AL, MS Yes 36.3 (22.5) 6.1 (3.8) 42.4 (26.3) SP12 Duck River, TN Yes 284.0 (176.5) 63.5 (39.4) 347.5 (215.9) SP13 Buffalo River, TN Yes 50.0 (31.0) 0 50.0 (31.0) Total 1,561.8 (970.3) Eleven critical habitat units designated for the fluted kidneyshell, slabside pearlymussel, or both species are currently designated as critical habitat under the Act for other species, including the purple bean ( Villosa perpurpurea ), oyster mussel, Cumberlandian combshell, Cumberland elktoe ( Alasmidonta atropurpurea ), rough rabbitsfoot, rabbitsfoot, slender chub ( Erimystax cahni ), and yellowfin madtom ( Noturus flavipinnis ) (42 FR 45526, 78 FR 57076, 42 FR 47840, 69 FR 53136) (see Table 3). The designated units for the fluted kidneyshell and slabside pearlymussel completely or partially overlap existing units in the Powell, Clinch, Nolichucky, Big South Fork Cumberland, Duck, and Paint Rock Rivers and in the Buck, Rock, Indian, Copper, and Bear Creeks; however, the exact unit descriptions (lengths) differ due to mapping refinement since the earlier designations. Three critical habitat units designated for the fluted kidneyshell and slabside pearlymussel are currently designated under section 10(j) of the Act as NEPs for other species, including the yellowfin madtom in the North Fork Holston River, VA; and 15 mussels, 1 snail, and 5 fishes in the lower Holston and French Broad Rivers, TN (53 FR 29335, 72 FR 52434, see Table 3). All of the critical habitat units designated for the fluted kidneyshell and slabside pearlymussel contain historical or extant records of federally listed or proposed species, except for the Wolf River and Town Branch and West Fork Obey River, TN (see Table 4). Table 3—Critical Habitat Units Designated for the Fluted Kidneyshell and Slabside Pearlymussel That Are Currently Designated or Proposed as Critical Habitat or Nonessential Experimental Populations (NEPs) for Other Federally Listed Species Unit (Unit No.) Species Critical habitat Nonessential experimental population Length of overlap rkm (rmi) Buck Creek (FK4) Oyster mussel, Cumberlandian 69 FR 53136 61 (38) Rock Creek (FK5) Cumberland elktoe 69 FR 53136 19 (12) Big South Fork Cumberland River (FK7) Oyster mussel, Cumberlandian combshell, Cumberland elktoe 69 FR 53136 92 (57) Indian Creek (FK10) Purple bean, Oyster mussel, Cumberlandian combshell, Rough rabbitsfoot 69 FR 53136 7 (4) North Fork Holston River (FK12, SP1) Yellowfin madtom 53 FR 29335 58 (36) Copper Creek (FK15) Purple bean, Oyster mussel, Cumberlandian combshell, Rough rabbitsfoot, Yellowfin madtom 69 FR 53136, 42 FR 45526, 42 FR 47840 21 (13), 56 (35), 56 (35) Clinch River (FK16, SP4) Purple bean, Oyster mussel, Cumberlandian combshell, Rough rabbitsfoot, Slender chub, Yellowfin madtom 69 FR 53136, 42 FR 45526, 42 FR 47840 263 (163), 263 (163), 263 (163) Powell River (FK17, SP5) Purple bean, Cumberlandian combshell, Oyster mussel, Rough rabbitsfoot, Slender chub, Yellowfin madtom 69 FR 53136, 42 FR 45526, 42 FR 47840 153 (95), 153 (95), 153 (95) Nolichucky River (FK18, SP6) Oyster mussel, Cumberlandian combshell 69 FR 53136 8 (5) Holston River (FK19) 15 Mussels, 1 Snail, and 5 Fishes 72 FR 52434 85 (53) French Broad River (FK20) 15 Mussels, 1 Snail, and 5 Fishes 72 FR 52434 56 (35) Paint Rock River (SP9) Rabbitsfoot 78 FR 57076 81 (50) Bear Creek, (SP11) Oyster mussel, Cumberlandian combshell, Rabbitsfoot 69 FR 53136, 78 FR 57076 42 (26), 42 (26) Duck River (FK23, SP12) Oyster mussel, Cumberlandian combshell, Rabbitsfoot 69 FR 53136, 78 FR 57076 74 (46), 235 (146) Critical Habitat Overlap 1,017 (631) NEP Overlap 199 (124) Total Overlap 1,216 (755) Note: For those units with critical habitat designations for more than one species, the critical habitat unit with the longest length of overlap was used to calculate the total overlap (e.g., Duck River is critical habitat for the oyster mussel (74 rkm) and rabbitsfoot (235 rkm). The designated units for the fluted kidneyshell and slabside pearlymussel completely or partially overlap existing units in the Powell, Clinch, Nolichucky, Big South Fork Cumberland, Duck, and Paint Rock Rivers and in the Buck, Rock, Indian, Copper, and Bear Creeks; however, the exact unit descriptions (lengths) differ due to mapping refinement since the earlier designations. Table 4—Other Federally Listed or Proposed Species With Historical or Extant Records From the Designated Critical Habitat Unit Streams for the Fluted Kidneyshell and Slabside Pearlymussel Unit Location Federally Listed or Proposed Species Present FK1 Horse Lick Creek, KY Cumberland bean Villosa trabalis. littlewing pearlymussel Pegias fabula. FK2 Middle Fork Rockcastle River, KY Cumberland bean Villosa trabalis. FK3 Rockcastle River, KY Cumberland bean Villosa trabalis. Cumberlandian combshell Epioblasma brevidens. littlewing pearlymussel Pegias fabula. oyster mussel Epioblasma capsaeformis. FK4 Buck Creek, KY Cumberland bean Villosa trabalis. Cumberlandian combshell Epioblasma brevidens. littlewing pearlymussel Pegias fabula. oyster mussel Epioblasma capsaeformis. snuffbox Epioblasma triquetra. yellow blossom Epioblasma florentina florentina. FK5 Rock Creek, KY Cumberland elktoe Alasmidonta atropurpurea. FK6 Little South Fork Cumberland River, KY Cumberland bean Villosa trabalis. littlewing pearlymussel Pegias fabula. oyster mussel Epioblasma capsaeformis. snuffbox Epioblasma triquetra. palezone shiner Notropis albizonatus. FK7 Big South Fork Cumberland River, KY Cumberland bean Villosa trabalis. Cumberlandian combshell Epioblasma brevidens. Cumberland elktoe Alasmidonta atropurpurea. dromedary pearlymussel Dromus dromas. littlewing pearlymussel Pegias fabula. oyster mussel Epioblasma capsaeformis. spectaclecase Cumberlandia monodonta. tan riffleshell Epioblasma florentina walkeri (=E. walkeri). duskytail darter Etheostoma percnurum. FK8 Wolf River and Town Branch, TN None FK9 West Fork Obey River, TN None FK10 Indian Creek, VA purple bean Villosa perpurpurea. tan riffleshell Epioblasma florentina walkeri (=E. walkeri). rough rabbitsfoot Quadrula cylindrica strigillata. FK11 Little River, VA finerayed pigtoe Fusconaia cuneolus. littlewing pearlymussel Pegias fabula. oyster mussel Epioblasma capsaeformis. FK12, SP1 North Fork Holston River, VA littlewing pearlymussel Pegias fabula. purple bean Villosa perpurpurea. rough rabbitsfoot Quadrula cylindrica strigillata. shiny pigtoe Fusconaia cor. snuffbox Epioblasma triquetra. spotfin chub Erimonax monachus. FK13, SP2 Middle Fork Holston River, VA littlewing pearlymussel Pegias fabula. shiny pigtoe Fusconaia cor. tan riffleshell Epioblasma florentina walkeri (=E. walkeri). yellow blossom Epioblasma florentina florentina. spotfin chub Erimonax monachus. FK14, SP3 Big Moccasin Creek, VA finerayed pigtoe Fusconaia cuneolus. littlewing pearlymussel Pegias fabula. oyster mussel Epioblasma capsaeformis. rough rabbitsfoot Quadrula cylindrica strigillata. FK15 Copper Creek, VA finerayed pigtoe Fusconaia cuneolus. littlewing pearlymussel Pegias fabula. oyster mussel Epioblasma capsaeformis. purple bean Villosa perpurpurea. rough rabbitsfoot Quadrula cylindrica strigillata. shiny pigtoe Fusconaia cor. duskytail darter Etheostoma percnurum. yellowfin madtom Noturus flavipinnis. FK16, SP4 Clinch River, TN, VA Appalachian monkeyface Quadrula sparsa. birdwing pearlymussel Lemiox rimosus. cracking pearlymussel Hemistena lata. Cumberland bean Villosa trabalis. Cumberlandian combshell Epioblasma brevidens. Cumberland monkeyface Quadrula intermedia. dromedary pearlymussel Dromus dromas. fanshell Cyprogenia stegaria. finerayed pigtoe Fusconaia cuneolus. green blossom pearlymussel Epioblasma torulosa gubernaculum. littlewing pearlymussel Pegias fabula. oyster mussel Epioblasma capsaeformis. pink mucket Lampsilis abrupta. purple bean Villosa perpurpurea. rayed bean Villosa fabalis. rough pigtoe Pleurobema plenum. rough rabbitsfoot Quadrula cylindrica strigillata. sheepnose Plethobasus cyphyus. shiny pigtoe Fusconaia cor. snuffbox Epioblasma triquetra. spectaclecase Cumberlandia monodonta. tan riffleshell Epioblasma florentina walkeri (=E. walkeri). yellow blossom Epioblasma florentina florentina. pygmy madtom Noturus stanauli. slender chub Erimystax cahni. FK17, SP5 Powell River, TN, VA Appalachian monkeyface Quadrula sparsa. birdwing pearlymussel Lemiox rimosus. cracking pearlymussel Hemistena lata. Cumberlandian combshell Epioblasma brevidens. Cumberland monkeyface Quadrula intermedia. dromedary pearlymussel Dromus dromas. finerayed pigtoe Fusconaia cuneolus. green blossom pearlymussel Epioblasma torulosa gubernaculum. oyster mussel Epioblasma capsaeformis. purple bean Villosa perpurpurea. rayed bean Villosa fabalis. rough rabbitsfoot Quadrula cylindrica strigillata. sheepnose Plethobasus cyphyus. shiny pigtoe Fusconaia cor. snuffbox Epioblasma triquetra. spectaclecase Cumberlandia monodonta. yellow blossom Epioblasma florentina florentina. slender chub Erimystax cahni. yellowfin madtom Noturus flavipinnis. FK18, SP6 Nolichucky River, TN Cumberlandian combshell Epioblasma brevidens. green blossom pearlymussel Epioblasma torulosa gubernaculum. oyster mussel Epioblasma capsaeformis. rayed bean Villosa fabalis. spectaclecase Cumberlandia monodonta. snail darter Percina tanasi. FK19 Holston River, TN Appalachian Monkeyface Quadrula sparsa. birdwing pearlymussel Lemiox rimosus. cracking pearlymussel Hemistena lata. Cumberlandian combshell Epioblasma brevidens. Cumberland monkeyface Quadrula intermedia. dromedary pearlymussel Dromus dromas. green blossom pearlymussel Epioblasma torulosa gubernaculum. oyster mussel Epioblasma capsaeformis. pink mucket Lampsilis abrupta. ring pink Obovaria retusa. sheepnose Plethobasus cyphyus. snuffbox Epioblasma triquetra. spectaclecase Cumberlandia monodonta. tan riffleshell Epioblasma florentina walkeri (=E. walkeri). turgid blossom pearlymussel Epioblasma turgidula. white wartyback Plethobasus cicatricosus. yellow blossom Epioblasma florentina florentina. slender chub Erimystax cahni. snail darter Percina tanasi. FK20 French Broad River, TN birdwing pearlymussel Lemiox rimosus. cracking pearlymussel Hemistena lata. dromedary pearlymussel Dromus dromas. fanshell Cyprogenia stegaria. orangefoot pimpleback Plethobasus cooperianus. oyster mussel Epioblasma capsaeformis. pink mucket Lampsilis abrupta. ring pink Obovaria retusa. rough pigtoe Pleurobema plenum. sheepnose Plethobasus cyphyus. shiny pigtoe Fusconaia cor. tubercled blossom pearlymussel Epioblasma torulosa torulosa. yellow blossom Epioblasma florentina florentina. snail darter Percina tanasi. FK21, SP7 Hiwassee River, TN Appalachian monkeyface Quadrula sparsa. Cumberland bean Villosa trabalis. dromedary pearlymussel Dromus dromas. orangefoot pimpleback Plethobasus cooperianus. oyster mussel Epioblasma capsaeformis. rough pigtoe Pleurobema plenum. sheepnose Plethobasus cyphyus. tan riffleshell Epioblasma florentina walkeri (=E. walkeri). tubercled blossom pearlymussel Epioblasma torulosa torulosa. yellow blossom Epioblasma florentina florentina. SP8 Sequatchie River, TN Anthony's riversnail Athearnia anthonyi. snuffbox Epioblasma triquetra. spectaclecase Cumberlandia monodonta. snail darter Percina tanasi. SP9 Paint Rock River, AL Alabama lampmussel Lampsilis virescens. Cumberland bean Villosa trabalis. Cumberlandian combshell Epioblasma brevidens. finerayed pigtoe Fusconaia cuneolus. oyster mussel Epioblasma capsaeformis. pale lilliput Toxolasma cylindrellus. pink mucket Lampsilis abrupta. shiny pigtoe Fusconaia cor. snuffbox Epioblasma triquetra. yellow blossom Epioblasma florentina florentina. palezone shiner Notropis albizonatus. snail darter Percina tanasi. rabbitsfoot Quadrula cylindrica cylindrica. FK22, SP10 Elk River, AL, TN Alabama lampmussel Lampsilis virescens. birdwing pearlymussel Lemiox rimosus. cracking pearlymussel Hemistena lata. Cumberlandian combshell Epioblasma brevidens. Cumberland monkeyface Quadrula intermedia. dromedary pearlymussel Dromus dromas. fanshell Cyprogenia stegaria. finerayed pigtoe Fusconaia cuneolus. littlewing pearlymussel Pegias fabula. pale lilliput Toxolasma cylindrellus. rabbitsfoot Quadrula cylindrica cylindrica. rayed bean Villosa fabalis. shiny pigtoe Fusconaia cor. snuffbox Epioblasma triquetra. spectaclecase Cumberlandia monodonta. tan riffleshell Epioblasma florentina walkeri (=E. walkeri). tubercled blossom pearlymussel Epioblasma torulosa torulosa. turgid blossom pearlymussel Epioblasma turgidula. yellow blossom Epioblasma florentina florentina. boulder darter Etheostoma wapiti. snail darter Percina tanasi. SP11 Bear Creek, AL, MS Alabama lampmussel Lampsilis virescens. Cumberlandian combshell Epioblasma brevidens. oyster mussel Epioblasma capsaeformis. pink mucket Lampsilis abrupta. snuffbox Epioblasma triquetra. turgid blossom pearlymussel Epioblasma turgidula. yellow blossom Epioblasma florentina florentina. rabbitsfoot Quadrula cylindrica cylindrica. FK23, SP12 Duck River, TN birdwing pearlymussel Lemiox rimosus. clubshell Pleurobema clava. cracking pearlymussel Hemistena lata. Cumberlandian combshell Epioblasma brevidens. Cumberland monkeyface Quadrula intermedia. littlewing pearlymussel Pegias fabula. oyster mussel Epioblasma capsaeformis. pale lilliput Toxolasma cylindrellus. pink mucket Lampsilis abrupta. rayed bean Villosa fabalis. sheepnose Plethobasus cyphyus. snuffbox Epioblasma triquetra. spectaclecase Cumberlandia monodonta. tan riffleshell Epioblasma florentina walkeri (=E. walkeri). tubercled blossom pearlymussel Epioblasma torulosa torulosa. turgid blossom pearlymussel Epioblasma turgidula. winged mapleleaf Quadrula fragosa. yellow blossom Epioblasma florentina florentina. pygmy madtom Noturus stanauli. rabbitsfoot Quadrula cylindrica cylindrica. FK24, SP13 Buffalo River, TN pale lilliput Toxolasma cylindrellus. spotfin chub Erimonax monachus. rabbitsfoot Quadrula cylindrica cylindrica. For each stream reach designated as a critical habitat unit, the upstream and downstream boundaries are described generally below. More precise definitions are provided in the Regulation Promulgation section at the end of this final rule. For a discussion of the status and distribution of the fluted kidneyshell and slabside pearlymussel for each critical habitat unit, refer to the final listing rule published elsewhere in today's Federal Register . Fluted Kidneyshell and Slabside Pearlymussel Critical Habitat Under the first prong of the Act's definition of critical habitat, areas within the geographical area occupied by the species at the time it was listed must contain PBFs which are (1) essential to the conservation of the species and (2) which may require special management considerations or protection. For those units occupied by either the fluted kidneyshell, slabside pearlymussel, or both species, we describe the principal PBFs essential to the conservation of the species and the special management considerations or protections that may be needed for each unit below. Under the second prong of the Act's definition of critical habitat, we can designate critical habitat in areas outside the geographical area occupied by the species at the time it is listed, upon a determination that such areas are essential for the conservation of the species. For those units unoccupied by the fluted kidneyshell, we are designating these units because we have determined that they are essential for the conservation of the species due to the need to re-establish the species within other portions of its historical range in order to reduce threats from stochastic events. For four of the units (Big Moccasin Creek; Hiwassee, Elk, and Buffalo Rivers), we are designating critical habitat for the slabside pearlymussel under prong one of the Act (occupied), while at the same time designating the unit under prong two of the Act for the fluted kidneyshell species (unoccupied). Therefore, the principal PBFs and special management considerations or protections given for these units only apply to the species for which the unit is occupied critical habitat (slabside pearlymussel). Unit FK1: Horse Lick Creek, Rockcastle and Jackson Counties, Kentucky Unit FK1 encompasses approximately 19 rkm (12 rmi) of Horse Lick Creek, in Rockcastle and Jackson Counties, KY. It includes the mainstem of Horse Lick Creek from its confluence with the Rockcastle River upstream to Clover Bottom Creek. The unit is within the Cumberland River system and is critical habitat for the fluted kidneyshell. This unit is included in the geographical area occupied by the fluted kidneyshell at the time of listing. This unit is located almost entirely on private lands; however, approximately 16 rkm (10 rmi) are federal lands within the DBNF. Land and resource management decisions and activities within the DBNF are guided by DBNF's LRMP (USFS 2004a, pp. 1-14). The channel within Unit FK1 is relatively stable, with an abundance of riffle habitats (PCE 1), with relatively silt-free sand and gravel substrates (PCE 2), and adequate instream flows (PCE 3). A diverse fish fauna, including fish host(s) for the fluted kidneyshell, are known from this unit (PCE 5). Within Unit FK1, the fluted kidneyshell and its habitat may require special management considerations or protection to address potential adverse effects associated with legacy coal mines and coal mining activities, silviculture-related activities, natural gas and oil exploration activities in headwater reaches, illegal off-road vehicle use and other recreational activities, and nonpoint source pollution originating in headwater reaches. Unit FK2: Middle Fork Rockcastle River, Jackson County, Kentucky Unit FK2 includes 12.5 rkm (7.7 rmi) of the Middle Fork Rockcastle River from its confluence with the Rockcastle River upstream to its confluence with Indian Creek and Laurel Fork in Jackson County, KY. The unit is within the Cumberland River system and is occupied critical habitat for the fluted kidneyshell. About half of this unit (approximately 6 rkm (4 rmi)) is in public ownership (DBNF), and half is in private ownership. Land and resource management decisions and activities within the DBNF are guided by DBNF's LRMP (USFS 2004a, pp. 1-14). The channel within Unit FK2 is relatively stable and has an abundance of riffle habitats (PCE 1), with relatively silt-free sand and gravel substrates (PCE 2), and adequate instream flows (PCE 3). Within this unit, the fluted kidneyshell and its habitat may require special management considerations or protection to address potential adverse effects caused by resource extraction (coal mining, silviculture, natural gas and oil exploration activities), agricultural activities (livestock), lack of adequate riparian buffers, construction and maintenance of State and county roads, illegal off-road vehicle use, nonpoint source pollution arising from a wide variety of human activities, and potentially canopy loss caused by infestations of the hemlock woolly adelgid, Adelges tsugae, an invasive pest threatening eastern hemlock trees ( Tsuga canadensis ) in the eastern United States. Hemlocks are an important component of riparian vegetation throughout the range of the two mussels. Unit FK3: Rockcastle River, Pulaski, Laurel, and Rockcastle Counties, Kentucky Unit FK3 includes approximately 70 rkm (43 rmi) of the Rockcastle River from the backwaters of Lake Cumberland near its confluence with Cane Creek along the Laurel and Pulaski County line, KY, upstream to its confluence with Horse Lick Creek along the Laurel and Rockcastle County line, KY. The unit is within the Cumberland River system and is considered unoccupied by the fluted kidneyshell at the time of listing, but within the species' historical range. Live fluted kidneyshell have not been collected within Unit FK3 since 1911; however, it persists in adjacent tributaries such as Horse Lick Creek and shell material has been found as recently as 1985 (Wilson and Clark 1914 and Thompson 1985 in Cicerello 1993, p. 12). In 2010, surveys of the Rockcastle River showed that the river had a diverse mussel fauna, including the federally endangered Cumberland bean (McGregor 2010, unpubl. data). We consider this unit essential for the conservation of the fluted kidneyshell due to the need to re-establish the species within other portions of its historical range in order to reduce threats from stochastic events. Therefore, this unit is designated as unoccupied critical habitat for the fluted kidneyshell. A portion of this unit (approximately 12 rkm (7 rmi)) is in private ownership, but the majority is in public ownership (DBNF). Land and resource management decisions and activities within the DBNF are guided by DBNF's LRMP (USFS 2004a, pp. 1-14). Unit FK4: Buck Creek, Pulaski County, Kentucky Unit FK4 includes approximately 61 rkm (38 rmi) of Buck Creek from State Route 192 upstream to Route 328, Pulaski County, KY. The unit is within the Cumberland River basin and is critical habitat for the fluted kidneyshell. This unit is included in the geographical area occupied by the species at the time of listing. A portion of this unit (1.3 rkm (0.8 rmi)) is in public ownership (DBNF), but the majority is in private ownership. Land and resource management decisions and activities within the DBNF are guided by DBNF's LRMP (USFS 2004a, pp. 1- 14). The unit completely overlaps existing critical habitat for the oyster mussel and Cumberlandian combshell (69 FR 53136). The channel within Unit FK4 is relatively stable, with suitable instream habitat (PCE 1). There is an abundance of riffle habitats (PCE 1), with relatively silt-free sand and gravel substrates (PCE 2), and adequate instream flows (PCE 3). A diverse fish fauna, including fish host(s) for the fluted kidneyshell, are known from this unit (PCE 5). Within this unit, the fluted kidneyshell and its habitat may require special management considerations or protection to address potential adverse effects associated with instream gravel mining, silviculture-related activities, illegal off-road vehicle use and other recreational activities, and nonpoint source pollution from agricultural and developmental activities. Unit FK5: Rock Creek, McCreary County, Kentucky Unit FK5 includes approximately 19 rkm (12 rmi) of Rock Creek from its confluence with White Oak Creek upstream to the low water crossing at rkm 25.6 (rmi 15.9) in McCreary County, KY. The unit is within the Cumberland River system and is critical habitat for the fluted kidneyshell. This unit is included in the geographical area occupied by the species at the time of listing. A portion of this unit (1.5 rkm (0.9 rmi)) is in private ownership, but the majority is in public ownership (DBNF). Land and resource management decisions and activities within the DBNF are guided by DBNF's LRMP (USFS 2004a, pp. 1-14). The unit completely overlaps existing critical habitat for the Cumberland elktoe (69 FR 53136). The channel within Unit FK5 is relatively stable, with suitable instream habitat (PCE 1). There is an abundance of riffle habitats (PCE 1), with relatively silt-free sand and gravel substrates (PCE 2), and adequate instream flows (PCE 3). A diverse fish fauna, including fish host(s) for the fluted kidneyshell, are known from this unit (PCE 5). Within this unit, the fluted kidneyshell and its habitat may require special management considerations or protection to address potential adverse effects caused by resource extraction (coal mining, silviculture, natural gas and oil exploration activities), agricultural activities (livestock), lack of adequate riparian buffers, construction and maintenance of State and county roads, illegal off-road vehicle use, nonpoint source pollution arising from a wide variety of human activities, and potentially canopy loss caused by infestations of the hemlock woolly adelgid. Unit FK6: Little South Fork Cumberland River, McCreary and Wayne Counties, Kentucky Unit FK6 includes 65.5 rkm (40.7 rmi) of the Little South Fork Cumberland River from its confluence with the Big South Fork Cumberland River, where it is the dividing line between Wayne and McCreary Counties, upstream to its confluence with Dobbs Creek in Wayne County, KY. The unit is within the Cumberland River system and is critical habitat for the fluted kidneyshell. This unit is included in the geographical area occupied by the species at the time of listing. A portion of this unit (4.4 rkm (2.7 rmi)) is in public ownership (DBNF), but the majority is in private ownership. Land and resource management decisions and activities within the DBNF are guided by DBNF's LRMP (USFS 2004a, pp. 1-14). The channel within Unit FK6 is relatively stable, with an abundance of riffle habitats (PCE 1), relatively silt-free sand and gravel substrates (PCE 2), and adequate instream flows (PCE 3). A diverse fish fauna, including fish host(s) for the fluted kidneyshell, are known from this unit (PCE 5). Within this unit, the fluted kidneyshell and its habitat may require special management considerations or protection to address potential adverse effects caused by resource extraction (coal mining, silviculture, natural gas and oil exploration activities), agricultural activities (livestock), lack of adequate riparian buffers, construction and maintenance of State and county roads, illegal off-road vehicle use, nonpoint source pollution arising from a wide variety of human activities, and potentially canopy loss caused by infestations of the hemlock woolly adelgid. Unit FK7: Big South Fork Cumberland River, Fentress, Morgan, and Scott Counties, Tennessee, and McCreary County, Kentucky Unit FK7 includes a combined total of approximately 92 rkm (57 rmi) of the Big South Fork of the Cumberland River, Clear Fork of the New River, and the New River in Tennessee and Kentucky. Unit FK7 includes approximately 45 rkm (28 rmi) of the Big South Fork Cumberland River from its confluence with Laurel Crossing Branch downstream of Big Shoals, McCreary County, KY, upstream to its confluence with Clear Fork and of the New River, Scott County, TN. This unit also includes 32.3 rkm (20.0 rmi) of Clear Fork from its confluence with the Big South Fork and New River in Scott County, TN, upstream to its confluence with Crooked Creek along the Fentress and Morgan County line, TN. This unit also includes 14.7 rkm (9.1 rmi) of the New River from its confluence with the Big South Fork upstream to the Highway 27 Bridge crossing in Scott County, TN. The unit is within the Cumberland River system and is designated as critical habitat for the fluted kidneyshell. This unit is included in the geographical area occupied by the species at the time of listing. A portion of this unit (92 rkm (57 rmi)) has been designated as critical habitat for the Cumberlandian combshell, oyster mussel, and Cumberland elktoe (69 FR 53136). This unit is located almost entirely on federal lands within the BSFNRRA. Land and resource management decisions and activities within the BSFNRRA are guided by the National Park Service General Management Plan, Field Management Plan, and Draft Non-Federal Oil and Gas Management Plan (NPS 2005, entire; NPS 2006, pp. 1-12; NPS 2011, entire). The channel within Unit FK7 is relatively stable, with relatively silt-free sand and gravel substrates (PCE 2) and adequate instream flows (PCE 3). A diverse fish fauna, including fish host(s) for the fluted kidneyshell, are known from this unit (PCE 5). Within this unit, the fluted kidneyshell and its habitat may require special management considerations or protection to address potential adverse effects caused by resource extraction (coal mining, silviculture, natural gas and oil exploration activities), lack of adequate riparian buffers, construction and maintenance of roads, recreational horse riding, illegal off-road vehicle use, nonpoint source pollution arising from a wide variety of human activities, and potential canopy loss caused by infestations of the hemlock woolly adelgid. Unit FK8: Wolf River and Town Branch, Pickett and Fentress Counties, Tennessee Unit FK8 includes 41.0 rkm (25.5 rmi) of the Wolf River from its inundation at Dale Hollow Lake in Pickett County, TN, upstream to its confluence with Delk Creek in Fentress County, TN, and 3.4 rkm (2.0 rmi) of Town Branch from its confluence with Wolf River upstream to its headwaters in Pickett County, TN. The unit is within the Cumberland River system and is critical habitat for the fluted kidneyshell. This unit is included in the geographical area occupied by the species at the time of listing. A portion of this unit (6 rkm (4 rmi)) is in public ownership (U.S. Army Corps of Engineers lands adjacent to Dale Hollow Reservoir and Sgt. Alvin C. York State Historic Park), but the majority is in private ownership. The channel within Unit FK8 is relatively stable, with suitable instream habitat (PCE 1). There is an abundance of riffle habitats (PCE 1), with relatively silt-free sand and gravel substrates (PCE 2) and adequate instream flows (PCE 3). A diverse fish fauna, including fish host(s) for the fluted kidneyshell, are known from this unit (PCE 5). Within this unit, the fluted kidneyshell and its habitat may require special management considerations or protection to address potential adverse effects associated with coal mining, silviculture-related activities, natural gas and oil exploration activities in headwater reaches, agricultural activities (livestock), lack of adequate riparian buffers, construction and maintenance of State and county roads, off-road vehicle use and other recreational activities, nonpoint source pollution originating in headwater reaches, and potential canopy loss caused by infestations of the hemlock woolly adelgid. Unit FK9: West Fork Obey River, Overton County, Tennessee Unit FK9 includes approximately 19 rkm (12 rmi) of the West Fork Obey River from the Highway 52 Bridge crossing upstream to its confluence with Dry Hollow Creek in Overton County, TN. The unit is within the Cumberland River system and is critical habitat for the fluted kidneyshell. This unit is included in the geographical area occupied by the species at the time of listing. This unit is located almost entirely on private land, except for any small amount that is publicly owned in the form of bridge crossings and road easements. The channel within Unit FK9 is relatively stable, with suitable instream habitat (PCE 1). There is an abundance of riffle habitats (PCE 1), with relatively silt-free sand and gravel substrates (PCE 2), and adequate instream flows (PCE 3). A diverse fish fauna, including fish host(s) for the fluted kidneyshell, are known from this unit (PCE 5). Within this unit, the fluted kidneyshell and its habitat may require special management considerations or protection to address potential adverse effects associated with coal mining, silviculture-related activities, natural gas and oil exploration activities in headwater reaches, off-road vehicle use and other recreational activities, agricultural activities (livestock), lack of adequate riparian buffers, construction and maintenance of State and county roads, nonpoint source pollution originating in headwater reaches, and potential canopy loss caused by infestations of the hemlock woolly adelgid. Unit FK10: Indian Creek, Tazewell County, Virginia Unit FK10 includes 6.7 rkm (4.2 rmi) of Indian Creek from its confluence with the Clinch River upstream to the fourth Norfolk Southern Railroad crossing at Van Dyke in Tazewell County, VA. The unit is within the Tennessee River system and is critical habitat for the fluted kidneyshell. This unit is included in the geographical area occupied by the species at the time of listing. This unit is located almost entirely on private land, except for any small amount that is publicly owned in the form of bridge crossings and road easements. The unit completely overlaps critical habitat for the Cumberlandian combshell, rough rabbitsfoot, purple bean, and oyster mussel (69 FR 53136). The channel within Unit FK10 is relatively stable, with suitable instream habitat (PCE 1). There is an abundance of riffle habitats (PCE 1), with relatively silt-free sand and gravel substrates (PCE 2), and adequate instream flows (PCE 3). A diverse fish fauna, including fish hosts for the fluted kidneyshell, are known from this unit (PCE 5). Within this unit, the fluted kidneyshell and its habitat may require special management considerations or protection to address potential adverse effects associated with residential development, coal mining, silviculture-related activities, natural gas and oil exploration activities in headwater reaches, illegal off-road vehicle use and other recreational activities, and nonpoint source pollution originating in headwater reaches. Unit FK11: Little River, Russell and Tazewell Counties, Virginia Unit FK11 includes approximately 50 rkm (31 rmi) of Little River from its confluence with the Clinch River in Russell County, VA, upstream to its confluence with Liberty and Maiden Spring Creeks in Tazewell County, VA. The unit is within the Tennessee River system and is critical habitat for the fluted kidneyshell. This unit is included in the geographical area occupied by fluted kidneyshell at the time of listing. This unit is located almost entirely on private land, except for any small amount that is publicly owned in the form of bridge crossings and road easements. The Nature Conservancy also owns a small portion of adjacent property. The channel within Unit FK11 is relatively stable, with suitable instream habitat (PCE 1). There is an abundance of riffle habitats (PCE 1), with relatively silt-free sand and gravel substrates (PCE 2), and adequate instream flows (PCE 3). A diverse fish fauna, including fish hosts for the fluted kidneyshell and slabside pearlymussel, are known from this unit (PCE 5). Within this unit, the fluted kidneyshell and its habitats may require special management considerations or protection to address potential adverse effects associated with silviculture-related activities, lack of adequate riparian buffers, natural gas and oil exploration activities in headwater reaches, and nonpoint source pollution originating in headwater reaches. Unit FK12 and SP1: North Fork Holston River, Smyth and Bland Counties, Virginia Unit FK12 and SP1 includes approximately 67 rkm (42 rmi) of the North Fork Holston River from its confluence with Beaver Creek, upstream of Saltville, in Smyth County, VA, upstream to Ceres, Bland County, VA. The unit is within the Tennessee River system and is critical habitat for the fluted kidneyshell and slabside pearlymussel. This unit is included in the geographical area occupied by both species at the time of listing. This unit is located almost entirely on private land, except for any small amount that is publicly owned in the form of bridge crossings, road easements, and a small portion that is adjacent to the George Washington and Jefferson National Forests. The Nature Conservancy and the Virginia Outdoors Foundation also own a small portion of adjacent property. A portion of this unit (58 rkm (36 rmi)) has been designated as a NEP for the yellowfin madtom (53 FR 29335). The channel within Unit FK12 and SP1 is relatively stable, with suitable instream habitat (PCE 1). There is an abundance of riffle habitats (PCE 1), with relatively silt-free sand and gravel substrates (PCE 2), and adequate instream flows (PCE 3). A diverse fish fauna, including fish hosts for the fluted kidneyshell and slabside pearlymussel, are known from this unit (PCE 5). Within this unit, the fluted kidneyshell, slabside pearlymussel, and their habitats may require special management considerations or protection to address potential adverse effects associated with agricultural activities, silviculture-related activities, natural gas and oil exploration activities in headwater reaches, lack of adequate riparian buffers, construction and maintenance of State and county roads, and nonpoint source pollution originating in headwater reaches. Unit FK13 and SP2: Middle Fork Holston River, Washington, Smyth, and Wythe Counties, Virginia Unit FK13 and SP2 includes approximately 89 rkm (55 rmi) of the Middle Fork Holston River from its inundation at South Holston Lake in Washington County, VA, upstream to its headwaters in Wythe County, VA. The unit is within the Tennessee River system and is critical habitat for the fluted kidneyshell and slabside pearlymussel. This unit is included in the geographical area occupied by both the fluted kidneyshell and slabside pearlymussel at the time of listing. This unit is located almost entirely on private land, except for any small amount that is publicly owned in the form of bridge crossings and road easements. The channel within Unit FK13 and SP2 is relatively stable, with suitable instream habitat (PCE 1). There is an abundance of riffle habitats (PCE 1), with relatively silt-free sand and gravel substrates (PCE 2), and adequate instream flows (PCE 3). A diverse fish fauna, including fish hosts for the fluted kidneyshell and slabside pearlymussel, are known from this unit (PCE 5). Within this unit, the fluted kidneyshell, slabside pearlymussel, and their habitats may require special management considerations or protection to address potential adverse effects associated with agricultural activities, lack of adequate riparian buffers, silviculture-related activities, and nonpoint source pollution. Unit FK14 and SP3: Big Moccasin Creek, Scott and Russell Counties, Virginia Unit FK14 and SP3 includes approximately 33 rkm (21 rmi) of Big Moccasin Creek from the Highway 71 Bridge crossing in Scott County, VA, upstream to the Route 612 Bridge crossing near Collinwood in Russell County, VA. The unit is within the Tennessee River system and is critical habitat for the fluted kidneyshell and slabside pearlymussel. This unit is included in the geographical area occupied by slabside pearlymussel at the time of listing. This unit is considered unoccupied by the fluted kidneyshell, but within the species' historical range. Live fluted kidneyshell have not been collected in Big Moccasin Creek since the early 1900s (Ortmann 1918, p. 608). However, this unit is designated as critical habitat for the fluted kidneyshell because it is considered essential for the conservation of the species (see Criteria Used To Identify Critical Habitat above for our rationale). This unit is located almost entirely on private land, except for any small amount that is publicly owned in the form of bridge crossings and road easements. The channel within Unit FK14 and SP3 is relatively stable, with suitable instream habitat (PCE 1). There is an abundance of riffle habitats (PCE 1), with relatively silt-free sand and gravel substrates (PCE 2), and adequate instream flows (PCE 3). A diverse fish fauna, including fish hosts for the slabside pearlymussel, are known from this unit (PCE 5). Within this unit, the slabside pearlymussel and its habitats may require special management considerations or protection to address potential adverse effects associated with agricultural activities (livestock), lack of adequate riparian buffers, silviculture-related activities, natural gas and oil exploration activities in headwater reaches, illegal off-road vehicle use and other recreational activities, and nonpoint source pollution originating in headwater reaches. Unit FK15: Copper Creek, Scott County, Virginia Unit FK15 includes 55.5 rkm (34.5 rmi) of Copper Creek from its confluence with the Clinch River upstream to the Highway 71 Bridge crossing in Scott County, VA. The unit is within the Tennessee River system and is critical habitat for the fluted kidneyshell. This unit is included in the geographical area occupied by the species at the time of listing. This unit is located almost entirely on private land, except for any small amount that is publicly owned in the form of bridge crossings and road easements. A portion of this unit (21 rkm (13 rmi)) has been designated as critical habitat for the Cumberlandian combshell, rough rabbitsfoot, purple bean, and oyster mussel, and this unit (55.5 rkm (34.5 rmi)) also makes up a portion of the designated critical habitat for the yellowfin madtom (42 FR 45526, 42 FR 47840, 69 FR 53136). The channel within Unit FK15 is relatively stable, with suitable instream habitat (PCE 1). There is an abundance of riffle habitats (PCE 1), with relatively silt-free sand and gravel substrates (PCE 2), and adequate instream flows (PCE 3). A diverse fish fauna, including fish hosts for the fluted kidneyshell, are known from this unit (PCE 5). Within this unit, the fluted kidneyshell and its habitat may require special management considerations or protection to address potential adverse effects associated with agricultural activities (livestock), silviculture-related activities, lack of adequate riparian buffers, construction and maintenance of State and county roads, and nonpoint source pollution originating in headwater reaches. Unit FK16 and SP4: Clinch River, Hancock County, Tennessee, and Scott, Russell, and Tazewell Counties, Virginia Unit FK16 and SP4 includes approximately 263 rkm (163 rmi) of the Clinch River from rkm 255 (rmi 159) immediately below Grissom Island in Hancock County, TN, upstream to its confluence with Indian Creek near Cedar Bluff, Tazewell County, VA. The unit is within the Tennessee River system and is critical habitat for the fluted kidneyshell and slabside pearlymussel. This unit is included in the geographical area occupied by both species at the time of listing. Approximately 6 rkm (4 rmi) of this unit is in public ownership, including portions of the Kyles Ford State Managed Area, George Washington National Forest, Jefferson National Forest, Cleveland Barrens State Natural Area Preserve (SNAP), and the Pinnacle SNAP. The Nature Conservancy also owns a small portion of adjacent property. The unit completely overlaps critical habitat for the Cumberlandian combshell, rough rabbitsfoot, purple bean, and oyster mussel, and the entire length of this unit has been designated as critical habitat for the slender chub and yellowfin madtom (42 FR 45526, 42 FR 47840, 69 FR 53136). The channel within Unit FK16 and SP4 is relatively stable, with suitable instream habitat (PCE 1). There is an abundance of riffle habitats (PCE 1), with relatively silt-free sand and gravel substrates (PCE 2), and adequate instream flows (PCE 3). A diverse fish fauna, including fish hosts for the fluted kidneyshell and slabside pearlymussel, are known from this unit (PCE 5). Within this unit, the fluted kidneyshell, slabside pearlymussel, and their habitats may require special management considerations or protection to address potential adverse effects associated with coal mining, silviculture-related activities, natural gas and oil exploration activities in headwater reaches, agricultural activities (livestock), lack of adequate riparian buffers, construction and maintenance of State and county roads, and nonpoint source pollution originating in headwater reaches. Unit FK17 and SP5: Powell River, Claiborne and Hancock Counties, Tennessee, and Lee County, Virginia Unit FK17 and SP5 includes approximately 153 rkm (95 rmi) of the Powell River from the U.S. 25E Bridge in Claiborne County, TN, upstream to rkm 256 (rmi 159) (upstream of Rock Island in the vicinity of Pughs) in Lee County, VA. The unit is within the Tennessee River system and is critical habitat for the fluted kidneyshell and slabside pearlymussel. This unit is included in the geographical area occupied by both speci [Text truncated at 120,000 characters. The full text is on the page linked above.] --- Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/fr%3A2013-23357. Public record. Not legal advice.