# Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for the Rayed Bean, Sheepnose, Snuffbox, and Spectaclecase Mussels > Briefs, arguments, decisions, and more. URL: https://www.frixlaw.com/law-library/documents/fr%3A2024-28316 ## Record - **Collection:** Federal Register - **Document type:** Proposed Rule - **Published:** December 13, 2024 - **Citation:** 89 FR 101100 ## Text DEPARTMENT OF THE INTERIOR Fish and Wildlife Service 50 CFR Part 17 [Docket No. FWS-R3-ES-2024-0144; FXES1111090FEDR-256-FF09E21000] RIN 1018-BH73 Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for the Rayed Bean, Sheepnose, Snuffbox, and Spectaclecase Mussels AGENCY: Fish and Wildlife Service, Interior. ACTION: Proposed rule. SUMMARY: We, the U.S. Fish and Wildlife Service (Service), propose to designate critical habitat for the rayed bean ( Villosa fabalis ), sheepnose ( Plethobasus cyphyus ), snuffbox ( Epioblasma triquetra ), and spectaclecase ( Cumberlandia monodonta ), all species of freshwater mussels, under the Endangered Species Act of 1973, as amended (Act). Specifically, we propose to designate approximately 560 river miles (rmi) (902 river kilometers (rkm)) in 15 units as critical habitat for rayed bean; approximately 801 rmi (1,289 rkm) in 11 units as critical habitat for sheepnose; approximately 2,472 rmi (3,979 rkm) in 38 units as critical habitat for snuffbox; and approximately 1,143 rmi (1,839 rkm) in 12 units as critical habitat for spectaclecase. Portions of these proposed designations overlap among the four species; in total, approximately 3,974 rmi (6,396 rkm) of unique critical habitat within 76 units across 17 States (Alabama, Arkansas, Illinois, Indiana, Iowa, Kentucky, Michigan, Minnesota, Mississippi, Missouri, New York, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia, and Wisconsin) fall within the boundaries of the proposed critical habitat designations. We also announce the availability of an economic analysis of the proposed designations of critical habitat for all four species. DATES: We will accept comments received or postmarked on or before February 11, 2025. Comments submitted electronically using the Federal eRulemaking Portal (see ADDRESSES , below) must be received by 11:59 p.m. eastern time on the closing date. We must receive requests for a public hearing, in writing, at the address shown in FOR FURTHER INFORMATION CONTACT by January 27, 2025. ADDRESSES: Written comments: You may submit comments by one of the following methods: (1) Electronically: Go to the Federal eRulemaking Portal: https://www.regulations.gov. In the Search box, enter FWS-R3-ES-2024-0144, which is the docket number for this rulemaking. Then, click on the Search button. On the resulting page, in the panel on the left side of the screen, under the Document Type heading, check the Proposed Rule box to locate this document. You may submit a comment by clicking on “Comment.” (2) By hard copy: Submit by U.S. mail to: Public Comments Processing, Attn: FWS-R3-ES-2024-0144, U.S. Fish and Wildlife Service, MS: PRB/3W, 5275 Leesburg Pike, Falls Church, VA 22041-3803. We request that you send comments only by the methods described above. We will post all comments on https://www.regulations.gov. This generally means that we will post any personal information you provide us (see Information Requested, below, for more information). Availability of supporting materials: Supporting materials, such as the species status assessment report, are available at https://www.regulations.gov at Docket No. FWS-R3-ES-2024-0144, or at the Service's website on each individual species' page (rayed bean: https://www.fws.gov/species/rayed-bean-villosa-fabalis; sheepnose: https://www.fws.gov/species/sheepnose-plethobasus-cyphyus; snuffbox: https://www.fws.gov/species/snuffbox-epioblasma-triquetra; spectaclecase: https://www.fws.gov/species/spectaclecase-cumberlandia-monodonta ). FOR FURTHER INFORMATION CONTACT: Rayed bean and snuffbox: Erin Knoll, Field Supervisor, U.S. Fish and Wildlife Service, Ohio Ecological Services Field Office, 4625 Morse Road, Suite 104, Columbus, OH 43230; telephone 614-416-8993; sheepnose: Kraig McPeek, Field Supervisor, U.S. Fish and Wildlife Service, Illinois-Iowa Ecological Services Field Office, 1511 47th Avenue, Moline, IL 61265; telephone 309-757-5800; spectaclecase: Betsy Galbraith, Acting Field Supervisor, U.S. Fish and Wildlife Service, Minnesota-Wisconsin Ecological Services Field Office, 3815 American Boulevard East, Bloomington, MN 55425; telephone 952-858-0793. Individuals in the United States who are deaf, deafblind, hard of hearing, or have a speech disability may dial 711 (TTY, TDD, or TeleBraille) to access telecommunications relay services. Individuals outside the United States should use the relay services offered within their country to make international calls to the point-of-contact in the United States. Please see Docket No. FWS-R3-ES-2024-0144 on https://www.regulations.gov for a document that summarizes this proposed rule. SUPPLEMENTARY INFORMATION: Executive Summary Why we need to publish a rule. Under the Act (16 U.S.C. 1531 et seq. ), when we determine that any species is an endangered or threatened species, we are required to designate critical habitat to the maximum extent prudent and determinable. Designation of critical habitat can be completed only by issuing a rule through the Administrative Procedure Act rulemaking process (5 U.S.C. 551 et seq. ). What this document does. We propose to designate critical habitat for the rayed bean, sheepnose, snuffbox, and spectaclecase mussels; these four freshwater mussel species have been listed as endangered species under the Act since 2012 (See 77 FR 8632, February 14, 2012, and 77 FR 14914, March 13, 2012). The basis for our action. Under section 4(a)(3) of the Act, if we determine a species is an endangered or threatened, we must, to the maximum extent prudent and determinable, designate critical habitat for the species. Section 3(5)(A) of the Act defines critical habitat as (i) the specific areas within the geographical area occupied by the species, at the time it is listed, on which are found those physical or biological features (I) essential to the conservation of the species and (II) which may require special management considerations or protections; and (ii) specific areas outside the geographical area occupied by the species at the time it is listed, upon a determination by the Secretary that such areas are essential for the conservation of the species. Section 4(b)(2) of the Act states that the Secretary must make the designation on the basis of the best scientific data available and after taking into consideration the economic impact, the impact on national security, and any other relevant impacts of specifying any particular area as critical habitat. Information Requested We intend that any final action resulting from this proposed rule will be based on the best scientific data available and be as accurate and as effective as possible. Therefore, we request comments or information from other governmental agencies, Native American Tribes, the scientific community, industry, or any other interested parties concerning this proposed rule. We particularly seek comments concerning: (1) Specific information related to critical habitat, such as: (a) The amount and distribution of rayed bean, sheepnose, snuffbox, and spectaclecase habitat; (b) Any additional areas occurring within the range of the species (Alabama, Arkansas, Illinois, Indiana, Iowa, Kentucky, Michigan, Minnesota, Mississippi, Missouri, New York, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia, and Wisconsin) that should be included in the designation because they (i) are occupied at the time of listing and contain the physical or biological features that are essential to the conservation of the species and that may require special management considerations or protection, or (ii) are unoccupied at the time of listing and are essential for the conservation of the species; and (c) Special management considerations or protection that may be needed in critical habitat areas we are proposing, including managing for the potential effects of climate change. (2) Land use designations and current or planned activities in the subject areas and their possible impacts on proposed critical habitat. (3) Any probable economic, national security, or other relevant impacts of designating any area that may be included in the final designations, and the related benefits of including or excluding specific areas. (4) Information on the extent to which the description of probable economic impacts in the economic analysis is a reasonable estimate of the likely economic impacts and any additional information regarding probable economic impacts that we should consider. (5) Whether any specific areas we are proposing for critical habitat designation should be considered for exclusion under section 4(b)(2) of the Act, and whether the benefits of potentially excluding any specific area outweigh the benefits of including that area, in particular for those areas included within the Columbia Pipeline Group Multi-Species Habitat Conservation Plan (formally NiSource; for more information, see our website at: https://www.fws.gov/project/columbia-pipeline-group-mshcp-formally-nisource ). If you think we should exclude any additional areas, please provide information supporting a benefit of exclusion. (6) Whether we could improve or modify our approach to designating critical habitat in any way to provide for greater public participation and understanding, or to better accommodate public concerns and comments. Please include sufficient information with your submission (such as scientific journal articles or other publications) to allow us to verify any scientific or commercial information you include. Please note that submissions merely stating support for, or opposition to, the action under consideration without providing supporting information, although noted, do not provide substantial information necessary to support a determination. Section 4(b)(2) of the Act directs that the Secretary shall designate critical habitat on the basis of the best scientific data available. You may submit your comments and materials concerning this proposed rule by one of the methods listed in ADDRESSES . We request that you send comments only by the methods described in ADDRESSES . If you submit information via https://www.regulations.gov, your entire submission—including any personal identifying information—will be posted on the website. If your submission is made via a hardcopy that includes personal identifying information, you may request at the top of your document that we withhold this information from public review. However, we cannot guarantee that we will be able to do so. We will post all hardcopy submissions on https://www.regulations.gov. Comments and materials we receive, as well as supporting documentation we used in preparing this proposed rule, will be available for public inspection on https://www.regulations.gov. Our final determinations may differ from this proposal because we will consider all comments we receive during the comment period as well as any information that may become available after this proposal. Based on the new information we receive (and, if relevant, any comments on that new information), our final critical habitat designations may not include all areas proposed, may include some additional areas that meet the definition of critical habitat, or may exclude some areas if we find the benefits of exclusion outweigh the benefits of inclusion and exclusion will not result in the extinction of the species. In our final rule, we will clearly explain our rationale and the basis for our final decisions, including why we made changes, if any, that differ from this proposal. Public Hearing Section 4(b)(5) of the Act provides for a public hearing on this proposal, if requested. Requests must be received by the date specified in DATES . Such requests must be sent to the address shown in FOR FURTHER INFORMATION CONTACT . We will schedule a public hearing on this proposal, if requested, and announce the date, time, and place of the hearing, as well as how to obtain reasonable accommodations, in the Federal Register and local newspapers at least 15 days before the hearing. We may hold the public hearing in person or virtually via webinar. We will announce any public hearing on our website, in addition to the Federal Register . The use of virtual public hearings is consistent with our regulations at 50 CFR 424.16(c)(3). Previous Federal Actions On November 2, 2010, we proposed to list the rayed bean and snuffbox mussels as endangered species under the Act (75 FR 67552). On January 19, 2011, we proposed to list the sheepnose and spectaclecase mussels as endangered species under the Act (76 FR 3392). In both cases, we considered the best available information and peer review and public comments on the proposed listing rules. We then published two final listing rules: the first to list the rayed bean and snuffbox mussels as endangered species under the Act (77 FR 8632; February 14, 2012) and the second to list the sheepnose and spectaclecase mussels as endangered species under the Act (77 FR 14914; March 13, 2012). Federal actions that occurred prior to February 14, 2012, or March 13, 2012, are outlined in our final listing rules for these species. For all four species, we found that critical habitat was prudent but not determinable at the time of listing. On July 2, 2018, the Center for Biological Diversity filed a complaint, challenging the failure of the Service to designate critical habitat for the four mussel species (rayed bean, sheepnose, snuffbox, and spectaclecase) within 1 year of the publication of our final listing rules. We entered a stipulated settlement agreement, which was approved by the court on June 4, 2019, requiring that we submit a determination concerning the designation of critical habitat for the four mussel species and a proposed rule for any species for which critical habitat is prudent to the Federal Register by November 30, 2024. This proposed rule complies with the stipulated settlement agreement. Peer Review A species status assessment (SSA) team prepared an SSA report for each of the four mussel species. The SSA team was composed of Service biologists, in consultation with other species experts. The SSA reports represent a compilation of the best scientific and commercial data available concerning the status of the species, including the impacts of past, present, and future factors (both negative and beneficial) affecting the species. In accordance with our joint policy on peer review published in the Federal Register on July 1, 1994 (59 FR 34270), and our August 22, 2016, memorandum updating and clarifying the role of peer review in listing and recovery actions under the Act, we solicited independent scientific review of the information contained in the SSA reports for the rayed bean (Service 2022a, entire), sheepnose (Service 2022b, entire), snuffbox (Service 2022c, entire), and spectaclecase (Service 2022d, entire). We sent the SSA reports to 10 independent peer reviewers and received 9 responses. We incorporated the results of these reviews, as appropriate, into the SSA reports, which are the foundation for this proposed rule. Results of the structured peer review process and all of the SSA reports can be found at https://www.regulations.gov at Docket No. FWS-R3-ES-2024-0144. Summary of Peer Reviewer Comments As discussed above in Peer Review, we received comments from nine unique peer reviewers on the draft SSA reports. We reviewed all comments we received from the peer reviewers for substantive issues and new information regarding the contents of each SSA report. Specifically, we reviewed the comments on each SSA report that would influence our considerations for critical habitat ( i.e., those related to our considerations of occupancy, habitat, and life-history characteristics used to define the essential physical or biological features for each species). Of the comments related to critical habitat considerations, the peer reviewers generally concurred with our conclusions and characterizations for each of the species in their respective SSA reports. Where the peer reviewers suggested corrections, we updated the SSA reports as appropriate ( e.g., clarifying the influence of dams as passage barriers and clarifying characterizations of host fish). Otherwise, no substantive changes within the SSA reports were deemed necessary, and peer reviewer comments are addressed in version 1.0 of the SSA reports. Background Critical habitat is defined in section 3(5)(A) 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. Our regulations at 50 CFR 424.02 define the geographical area occupied by the species as an area that may generally be delineated around species' occurrences, as determined by the Secretary ( i.e., range). Such areas may include those areas used throughout all or part of the species' life cycle, even if not used on a regular basis ( e.g., migratory corridors, seasonal habitats, and habitats used periodically, but not solely by vagrant individuals). Conservation, as defined under section 3(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 each Federal action agency 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 designated 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 also 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. Rather, designation requires that, where a landowner requests Federal agency funding or authorization for an action that may affect an area designated as critical habitat, the Federal agency consult with the Service under section 7(a)(2) of the Act. If the action may affect the listed species itself (such as for occupied critical habitat), the Federal agency would have already been required to consult with the Service even absent the designation because of the requirement to ensure that the action is not likely to jeopardize the continued existence of the listed species. Even if the Service were to conclude after consultation that the proposed activity is likely to result in destruction or adverse modification of the critical habitat, the Federal action agency and the landowner are not required to abandon the proposed activity, or to restore or recover the species; instead, they must 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 data available, those physical or biological features that are essential to the conservation of the species (such as space, food, cover, and protected habitat). 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. Section 4(b)(2) of the Act requires that we designate critical habitat on the basis of the best scientific 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 compiled in the SSA report and information developed during the listing process for the species. Additional information sources may include any generalized conservation strategy, criteria, or outline that may have been developed for the species; the recovery plan for the species; articles in peer-reviewed journals; conservation plans developed by States and counties; scientific status surveys and studies; biological assessments; other unpublished materials; or experts' opinions 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 ensure their actions are not likely to jeopardize the continued existence of any endangered or threatened species; and (3) the prohibitions found in section 9 of the Act. 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 the species. Similarly, critical habitat designations made on the basis of the best scientific data available 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 those planning efforts calls for a different outcome. Physical or Biological Features Essential to the Conservation of the Species In accordance with section 3(5)(A)(i) of the Act and regulations at 50 CFR 424.12(b), in determining which areas we will designate as critical habitat from within the geographical area occupied by the species at the time of listing, we consider the physical or biological features that are essential to the conservation of the species and which may require special management considerations or protection. The regulations at 50 CFR 424.02 define “physical or biological features essential to the conservation of the species” as the features that occur in specific areas and that are essential to support the life-history needs of the species, including, but not limited to, water characteristics, soil type, geological features, sites, prey, vegetation, symbiotic species, or other features. A feature may be a single habitat characteristic or a more complex combination of habitat characteristics. Features may include habitat characteristics that support ephemeral or dynamic habitat conditions. Features may also be expressed in terms relating to principles of conservation biology, such as patch size, distribution distances, and connectivity. For example, physical features essential to the conservation of the species might include gravel of a particular size required for spawning, alkaline soil for seed germination, protective cover for migration, or susceptibility to flooding or fire that maintains necessary early-successional habitat characteristics. Biological features might include prey species, forage grasses, specific kinds or ages of trees for roosting or nesting, symbiotic fungi, or absence of a particular level of nonnative species consistent with conservation needs of the listed species. The features may also be combinations of habitat characteristics and may encompass the relationship between characteristics or the necessary amount of a characteristic essential to support the life history of the species. In considering whether features are essential to the conservation of the species, we may consider an appropriate quality, quantity, and spatial and temporal arrangement of habitat characteristics in the context of the life-history needs, condition, and status of the species. These characteristics include, but are not limited to, space for individual and population growth and for normal behavior; food, water, air, light, minerals, or other nutritional or physiological requirements; cover or shelter; sites for breeding, reproduction, or rearing (or development) of offspring; and habitats that are protected from disturbance. General Mussel Biology Freshwater mussels, including the rayed bean, sheepnose, snuffbox, and spectaclecase mussels, have a complex life history that involves parasitic larvae, called glochidia, which are wholly reliant on host fish(es). As adult freshwater mussels are generally sessile, suspension-feeders that spend their entire lives partially or completely buried within the substrate (Call 1900, p. 459; Watters 1994, p. 105; West et al. 2000, p. 251), dispersal occurs solely through the behavior of their host fish(es). Mussels are broadcast spawners; males release sperm into the water column, which is taken in by the female. Fertilized eggs develop into microscopic larvae called glochidia within special gill chambers on the female mussel, and remain with the female until they are mature and ready for release as glochidia, to attach to their host fish(es) (Haag 2012, pp. 37-42). Glochidia will perish if they fail to attach to a suitable species of host fish, attach to a fish that has developed immunity from prior infestations, or attach to the wrong location on a host fish (Neeves 1991, p. 254; Bogan 1993, p. 599). Successful glochidia enyst (enclose in a cyst-like structure) on the host's tissue, draw nutrients from the host's tissue, and develop into juvenile mussels (Arey 1932, pp. 214-215). After a period of time when the glochidia transform into juveniles, they will excyst (drop off) from the fish and drop to the substrate on the bottom of the stream. Juveniles that drop in unsuitable substrates perish because their immobility prevents them from relocating to more favorable habitat. Juveniles burrow into interstitial substrates and grow to larger sizes that are less susceptible to predation and displacement from high-flow events (Yeager et al. 1994, p. 220). Adult mussels remain within the same general location where they excysted from their host fish as juveniles. Habitat Conditions, Suitable Substrates, and Flow Conditions All life stages of the rayed bean, sheepnose, snuffbox, and spectaclecase mussels require flowing water for survival. In general, all four species occur within small- to medium-sized creeks, to larger rivers, with rayed bean and snuffbox occasionally occurring along wave-washed shores of lakes (Call 1900, p. 459; Ortman 1919, p. 68; Stansbery 1967, entire; Buchanan 1980, p. 13; Neeves 1991, pp. 280-281; Cummings and Mayer 1992, pp. 50, 142, 162; Watters 1994, p. 105; Oesch 1995, p. 121; Parmalee and Bogan, 1998; pp. 50, 77, 108, 177, 244; Baird 2000, p. 5-6; West et al. 2000, pp. 251, 253; Badra 2002, pers. comm.; Butler 2002, p. 6; Williams et al. 2008, p. 498; Jones et al. 2019, p. 205). Within these areas, rayed bean typically occur in or near shoal or riffle (short, shallow length of stream where the stream flows more rapidly) areas, and in the shallow wave-washed areas of glacial lakes over gravel and sand substrates (West et al. 2000, p. 253). Sheepnose typically occur in shallow shoal habitats with moderate to swift currents—ranging from riffles of a few inches in depth to runs that exceed 20 feet (6 meters) in larger rivers—over mixtures of coarse sand, gravel, and clay (Ortman 1919, p. 68; Cummings and Mayer 1992, p. 50; Oesch 1995, p. 121; Parmalee and Bogan 1998, pp. 77, 177; Jones et al. 2019, p. 205). Snuffbox typically occur in swift currents of riffles and shoals in rivers and streams and the wave-washed shores of lakes over gravel and sand with occasional cobble and boulders (Cummings and Mayer 1992, p. 162; Parmaleee and Bogan 1998, p. 108). Spectaclecase typically occur in rivers and streams with slow to swift currents—often in quiet water near the interface of swift currents—over substrates that range from mud and sand to gravel, cobble, and boulders within relatively shallow riffles and shoals (Stansbery 1967, p. 29-30; Buchanan 1980, p. 13; Parmalee and Bogan 1998, p. 50; Baird 2000, p. 5-6). Appropriate flow is critical for delivering oxygen and nutrients for respiration and filtration ( i.e., survival and growth), essential for reproduction to allow glochidia to move to their host and encyst, as well as removing silt and other fine sediments from within rock structures and crevices, which prevents mussel suffocation and degradation of mussel and/or host-fish shelter habitats. Normal fluctuations in flow velocity are expected; however, extreme changes can be detrimental. Significant and/or prolonged increases in velocity, typically associated with flood conditions, has the potential to dislodge and scour mussels and move the bed, destroying habitat for the mussels and their host fishes (Holland-Bartels 1990, pp. 331-332; Layzer and Madison 1995, p. 135). Further, abnormally high velocities have the potential to cause glochidia mortality due to wash out and displacement of juveniles and adults. Alternatively, extreme low flows, typically associated with drought or water withdrawals, can impact reproduction, feeding, respiration, and in some cases, result in exposure and/or desiccation of the species (Fisher and LaVoy 1972 pp. 1473-1476; Stegman 2020, entire). Although some individuals are found in areas that experience seasonal low flows, areas that experience periodic drying or intermittent flow generally cannot support mussel assemblages. Appropriate water quality is critical to the survival, reproduction, and persistence of all life stages of freshwater mussels. Point and non-point source contaminants result in water quality and habitat degradation. Contaminants alter the chemical, physical, and biological characteristics of a stream, resulting in lethal and sub-lethal effects to mussels and their fish hosts. Although specific data for these parameters with respect to these four species are not directly available, mussels in general are similar in terms of sensitivity to certain thresholds, depending on the life stage exposed. In general, mussels need water temperatures below 86 degrees Fahrenheit (30 degrees Celsius), dissolved oxygen concentrations greater than 5 milligrams per liter (Pandolfo 2010, entire), and water quality concentrations below acute toxicity levels to mussels for contaminants such as total ammonia, nitrogen, copper, chloride, and sulfate (see Appendix B, Service 2022a, b, c, d). Habitat Connectivity A mussel population includes more than one mussel bed; it is the collection of mussel beds within a stream reach between which infested host fish may travel, allowing for ebbs and flows in mussel bed density and abundance through time throughout the population's occupied reach. Therefore, resilient populations of all four species must occupy connected stream reaches long enough so that stochastic events that affect individual mussel beds do not eliminate the entire population. Connectivity is characterized by suitable water quality, lack of barriers to dispersal ( e.g., perched culverts, hydropower dams that lack passage for host fishes, water control structures), and presence of suitable shelter habitat and forage base for host fish(es). Repopulation, through dispersal via infected host fish from other mussel beds within a given stream reach, can allow the population and individual beds within that population to recover from these stochastic events. Long stream reaches are more likely to support resilient populations into the future than shorter stream reaches; thus, long reaches of connected stream habitat is essential to support all life stages of all four species. Presence of Host Fish Species All four species are obligate parasites that rely on specific host-fish for developing into juvenile mussels and dispersal. Glochidia must come into contact with specific host fish to ensure survival; without the proper host fish, glochidia will perish and fail to transform into juvenile mussels. Each mussel species relies on a different suite of host fish(es). Rayed bean depend on darter and sculpin species as host fish; however, the exact suite of host fish species is unknown (Parmalee and Bogan, 1998, p. 245; West et al. 2000, p. 254). Gravid females attract host fish with a modified mantle flap. The only published studies identify the Tippecanoe darter ( Etheostoma tippecanoe ) and spotted darter ( E. maculatum ) as host fish (White et al. 1996, p. 191; Gibson et al. 2011, p. 7); however, these species are not (and were not) found throughout the species' current or historical range. Other host fishes are thought to include the greenside darter ( E. blenniodes ), rainbow darter ( E. caeruleum ), mottled sculpin ( Cottus bairdi ), and largemouth bass ( Micropterus salmoides ) (Woolnough 2002, p. 51). Based on closely related species that occur in the same areas and habitats, additional hosts may be susceptible, including species in the subgenus Nothonotus of Etheostoma, sculpins ( Cottus spp.), and fantail darter ( E. flabellare ) (Jones 2002, pers. comm.). Sheepnose depend on mimic shiner ( Notropis volucellus ) and sauger ( Sander canadensis ) as host fish; of these, only mimic shiner has been observed to be naturally infested and successfully facilitate transformation of juveniles in the lab and is most likely the primary host species. However, lab studies suggest that sheepnose may be able to use a wider variety of fish species including fathead minnow ( Pimephales promelas ), creek chub ( Semotilus atrromaculatus ), central stoneroller ( Campostoma anomalum ), brook stickleback ( Culaea inconstans ), and golden shiner ( Notemigonus cryoleucas ) (Watters et al. 2005, pp. 11-12; Bradley 2021, pers. comm.). Snuffbox mussels rely on darter and sculpin species as fish hosts, using log perch ( Percina caprodes ) as their primary host species. Female snuffbox lure host fish with an inflated mantle ( i.e., lure) and close their shell around the head of the fish long enough to expel their glochidia and allow for their attachment to the gills of the fish, before releasing the fish (Schwalb et al. 2011, p. 224). Given this life history strategy, they rely on clear water that allows their lures to be visible by potential fish hosts. Other potential host species from lab studies include the blackside darter ( P. maculata ), rainbow darter, Iowa darter ( E. exile ), blackspotted topminnow ( Fundulus olivaceous ), mottled sculpin, banded sculpin ( C. carolinae ), Ozark sculpin ( C. hypselurus ), largemouth bass, and brook stickleback ( Culaea inconstans ) (Sherman 1994, p. 17, Yeager and Saylor 1995, p. 3; Hillegass and Hove 1997, p. 25; Barnhart et al. 1998, p. 34; Hove et al. 2000, p. 30; Sherman Mulcrone 2004, pp. 100-103). Spectaclecase depend on mooneye ( Hiodon tergisus ) and goldeye ( Hiodon alosoides ) as host fishes (Sietman et al. 2017, p. 18). Natural infestations of spectaclecase have been observed on bigeye chub ( Hybopsis amblops ) and pealip redhorse ( Moxostoma pisolabrum ); however, they are not confirmed host fish species because juvenile mussels have not been observed transforming from these species in lab studies (Baird 2000, p. 24). Summary of Essential Physical or Biological Features We derive the specific physical or biological features essential to the conservation of the rayed bean, sheepnose, snuffbox, and spectaclecase from studies of the species' habitat, ecology, and life history as described above. Additional information can be found in the SSA report for each species (Service 2022a, pp. 3-10; Service 2022b, pp. 4-13; Service 2022c, pp. 3-11; Service 2022d, pp. 4-11; all SSA reports are available on https://www.regulations.gov at Docket No. FWS-R3-ES-2024-0144) and on the Service's website at the respective species' profile pages (see Availability of supporting materials under ADDRESSES , above). The primary habitat features that support resiliency of the four mussel species include flow regime, habitat connectivity, water and sediment quality, and the presence of host fish species. The link between these habitat features and the needs of each life stage of the four mussel species is summarized in table 1, below. Table 1—Habitat Requirements for Each Life Stage of the Four Mussel Species Life stage Supporting habitat or biological features Reference Fertilized eggs • Suitable water quality • Sexually mature males in proximity to sexually mature females • Suitable spawning water temperatures • Suitable flow conditions Ortman 1919, p. 66; Fuller 1974, pp. 240-241; Berg et al. 2008, p. 397; Haag 2012, pp. 38-39. Glochidia • Suitable water quality (clear water for visual attraction of host) • Availability of host fish for attachment ○ Rayed bean: darter and sculpin species ○ Sheepnose: mimic shiner ( Notropis volucellus ) and sauger ( Sander canadensis ) ○ Snuffbox: logperch ( Percina caprodes ) and darter and sculpin species ○ Spectaclecase: mooneye ( Hiodon tergisus ) and goldeye ( H. alosoides ) • Suitable water temperature • Suitable flow conditions to ensure glochidia encounter host Fuller 1974, pp. 240-241; Strayer 2008, p. 65; Guenther et al. 2009, p. 20; Haag 2012, pp. 41-42; Wolf et al. 2012, p. 7; Hove et al. 2015, pp. 4, 6-8, 12-13. Juveniles • Suitable water quality (appropriate interstitial chemistry, low salinity, low ammonia, low copper and other contaminants, high dissolved oxygen) • Suitable water temperature • Suitable flow conditions • Host fish dispersal • Food availability: smaller algae, detritus, bacteria, organic matter, pedal feeding for first several months • Suitable substrate conditions: ○ Rayed bean and snuffbox: stable sand and gravel ○ Sheepnose: firm/stable; coarse sand and gravel; cobble; may include mud ○ Spectaclecase: firm/stable; coarse sand, gravel, and rock free from excessive silt; may include large slabs/boulders Ortman 1919, p. 68; Fuller 1974, pp. 220-221, 238-246; Cummings and Mayer 1992, p. 50; Dimock and Wright 1993, pp. 188-190; Yeager et al. 1994, p. 221; Sparks and Strayer 1998, p. 132; Augspurger et al. 2003, p. 2,574; Augspurger et al. 2007, p. 2,025; Schwalb et al. 2011, entire; Strayer and Malcom 2012, pp. 1,787-1,788; Watters et al. 2009, p. 221. Adults • Suitable water quality (appropriate interstitial chemistry, low salinity, low ammonia, low copper and other contaminants, high dissolved oxygen) • Suitable water temperature • Suitable flow conditions • Food availability: algae, detritus, bacteria, dissolved organic matter, microscopic animals • Suitable substrate conditions: ○ Rayed bean and snuffbox: stable sand and gravel ○ Sheepnose: firm/stable; coarse sand and gravel; cobble; may include mud ○ Spectaclecase: firm/stable; coarse sand, gravel, and rock free from excessive silt; may include large slabs/boulders Ortmann 1919, p. 68; Fuller 1974, pp. 221, 240-246; Cummings and Mayer 1992, p. 50; Yeager et al. 1994, p. 221; Parmalee and Bogan 1998, p. 177; Nichols and Garling 2000, p. 881; Chen et al. 2001, pp. 213-214; Spooner and Vaughn 2008, p. 308; Watters et al. 2009, p. 221. We have determined that the following physical or biological features are essential to the conservation of the rayed bean, sheepnose, snuffbox, and spectaclecase: (i) Adequate flows, or a hydrological flow regime (magnitude, timing, frequency, duration, rate of change, and overall seasonality of discharge over time), necessary to maintain benthic habitats where the species are found and to maintain stream connectivity. (ii) Suitable substrates and connected instream habitats, characterized by geomorphologically stable stream channels and banks ( i.e., channels that maintain lateral dimensions, longitudinal profiles, and sinuosity patterns over time without an aggrading or degrading bed elevation) that support the four mussel species and their respective host fishes ( e.g., sand and gravel substrate with moderate flow, aquatic vegetation, in and adjacent to riffles and shoals). (iii) Water and sediment quality necessary to sustain natural physiological processes for normal behavior, growth, and viability of all life stages, including appropriate levels of dissolved oxygen (generally above 2 to 3 parts per million (ppm)), salinity (generally below 2 to 4 ppm), and temperature (generally below 86 degrees Fahrenheit (°F) (30 degrees Celsius (°C))). Additionally, concentrations of contaminants, including (but not limited to) ammonia, nitrate, copper, and chloride, are below acute toxicity levels for mussels. (iv) The presence and abundance of host fishes necessary for recruitment of the species. For the rayed bean, these are darter and sculpin species; for the sheepnose, these are mimic shiner ( Notropis volucellus ) and sauger ( Sander canadensis ); for the snuffbox, these are logperch ( Percina caprodes ) and darter and sculpin species; and for the spectaclecase, these are mooneye ( Hiodon tergisus ) and goldeye ( H. alosoides ). 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 which may require special management considerations or protection. The features essential to the conservation of the rayed bean, sheepnose, snuffbox, and spectaclecase may require special management considerations or protection to reduce the following threats: (1) construction or operation of reservoirs; (2) urbanization of the landscape, including (but not limited to) land conversion to impervious surfaces for urban and commercial use, infrastructure (pipelines, roads, bridges, utilities), and wastewater treatment; (3) significant alteration of water quality and nutrient pollution from a variety of activities, such as mining and agricultural activities; (4) land-use activities that remove large areas of forested wetlands and riparian systems; (5) culvert, dam, and pipe installation that creates barriers to movement for the mussels or their host fish; and (6) other watershed and floodplain disturbances that release sediments, pollutants, or nutrients into the water. Management activities that could ameliorate these threats include, but are not limited to, use of best management practices designed to reduce sedimentation, erosion, and bank destruction; protection of riparian corridors and woody vegetation; modification of dam operations and/or dam removal to more closely match natural flow regimes; improved stormwater management; and reduction of other watershed and floodplain disturbances that release sediments, pollutants, or nutrients into the water. Criteria Used To Identify Critical Habitat As required by section 4(b)(2) of the Act, we use the best scientific data available to designate critical habitat. In accordance with the Act and our implementing regulations at 50 CFR 424.12(b), we review available information pertaining to the habitat requirements of the species and identify specific areas within the geographical area occupied by the species at the time of listing and any specific areas outside the geographical area occupied by the species to be considered for designation as critical habitat. We are not currently proposing to designate any areas outside the geographical area occupied by the species because we have not identified any unoccupied areas that meet the definition of critical habitat, and we have determined that occupied areas are sufficient to conserve these four species. Within the recovery plans for all four species, we outline that recovery can be achieved by protecting and maintaining or enhancing existing occupied areas, with no need to create or establish new habitat areas or populations for all four species. Thus, the proposed designation includes only the occupied rivers and streams within the species' current range that contain the physical or biological features essential to the conservation of the species and that provide the best conditions for the maintenance and expansion of existing populations. Methodology Used for Selection of Proposed Units First, we identified those areas within the geographical areas occupied by the species at the time of listing and that contain the essential physical or biological features and determined which of these features may require special management considerations or protection. Most of these areas are where the high-condition populations, defined in the SSA report as stable to increasing populations with high estimated probability of persistence (or low risk), occur because these are the areas that contain the features that meet the four species' needs for maintaining viability. The presence of the essential physical or biological features in these areas result in populations that have recruitment, varied age class structures, and high-density populations that are important to conservation and recovery actions, as they may serve to bolster other diminished or extirpated populations. Second, we examined the overall contribution of moderate-condition populations—defined in the SSA report as stable to slightly decreasing populations with moderate probability of persistence (or moderate risk)—to viability of the species, as well as the amount of threats acting on those populations. We then considered adjacency and connectivity of these populations to the high-condition and other moderate-condition populations. We did not include populations that have potentially low likelihood of recovery due to limited abundances or lack of connectivity, and we did not include areas that do not contain the essential physical or biological features. Third, we evaluated spatial redundancy and representation across each of the four species' ranges to identify any remaining, consistently observable populations in a major river basin that may contain unique diversity or habitat or both. If we identified such populations, we include them in this proposed designation. For instance, the lower Mississippi River Basin is comprised of a single population of sheepnose within the Big Sunflower River of Bolivar and Sunflower Counties, Mississippi; this population is in low condition. However, this population exists at the southern edge of the species' range and may have unique genetic diversity that is not present elsewhere within the species' range, and this unit contains one or more of the essential physical or biological features. Thus, we include this stream segment in the sheepnose's proposed designation to enhance the likelihood of maintaining genetic diversity. Finally, we evaluated the overlap of the four species' occurrences, as well as their overlap with other listed aquatic species and designated critical habitat, where existing conservation and monitoring efforts may be ongoing. In areas with a high degree of overlap or existing conservation efforts, we included and/or extended areas of critical habitat within the overlapping areas. These areas were considered in formulating this proposed critical habitat designation because they contain the physical or biological features that are essential to the conservation of the species and that may require special management considerations. These areas may promote conservation and recovery through maintaining the ecological community and existing genetic diversity for the species. For all proposed critical habitat units, we define the upstream and downstream boundaries around areas that were occupied by the species at the time of listing and that contain the physical or biological features essential to conservation of the species using easily recognizable features ( e.g., confluence of two named streams, impoundments). Sources of data for these proposed critical habitat designations include multiple databases maintained by universities, information from State agencies throughout the species' ranges, and numerous survey reports on threats throughout the species' ranges (as cited in Service 2022a, entire; Service 2022b, entire; Service 2022c, entire; Service 2022d, entire; all reports are available on https://www.regulations.gov at Docket No. FWS-R3-ES-2024-0144). We also reviewed available information that pertains to the habitat requirements for these species. Sources of information on habitat requirements include studies conducted at occupied sites and published in peer-reviewed articles, agency reports, and data collected during monitoring efforts (as cited in Service 2022a, entire; Service 2022b, entire; Service 2022c, entire; Service 2022d, entire; all reports are available on https://www.regulations.gov at Docket No. FWS-R3-ES-2024-0144). River segments were defined using the National Hydrography Dataset Plus High Resolution (NHDPlus HR) dataset maintained by the U.S. Geological Survey (Moore et al. 2019, entire). In summary, for areas within the geographical area occupied by the species at the time of listing, we delineated critical habitat unit boundaries using the following criteria: (1) We identified river and stream reaches with observations from 2000 to present for rayed bean, sheepnose, and snuffbox, as well as river and stream reaches with observations from 1970 to present for spectaclecase, and considered these areas to be currently occupied. For spectaclecase, we determined that it is reasonable to find these areas occupied over a longer timeframe due to its longer lifespan (50 or more years on average), compared to the other mussel species (less than 30 years on average). For all species, the available State heritage databases and information, as well as increased survey efforts and detections of the species since 2012 in previously unknown areas of suitable habitat, support the likelihood of the species' continued presence in known occupied areas since the time of listing in 2012. (2) We delineated specific habitat areas based on Natural Heritage Element Occurrences, published reports, and unpublished survey data provided by States and other partners. These areas provide habitat for the four mussel species, despite fluctuations in local conditions. The areas within the proposed units represent continuous river and stream reaches of relatively free-flowing habitat patches capable of sustaining fish hosts and allowing for transport of glochidia, which are essential for reproduction and dispersal of these species. (a) Rayed bean: We are proposing to designate critical habitat for the rayed bean in the Black River, Pine River, Belle River, River Raisin, Clinton River, Fish Creek, Swan Creek, Blanchard River, Allegheny River, Olean Creek, Oil Creek, Oswayo Creek, French Creek, LeBoeuf Creek, Muddy Creek, Cussewago Creek, Little Darby Creek, Big Darby Creek, Great Miami River, and Tippecanoe River (see Proposed Critical Habitat Designation, below). All of these rivers and streams were known to be occupied at the time of listing except River Raisin, Oil Creek, Oswayo Creek, and Little Darby Creek. Although the rayed bean was not known from River Raisin (detected in 2015), Oil Creek (detected in 2015), Oswayo Creek (detected in 2015), and Little Darby Creek (detected in 2023) at the time of listing, all of the rivers and streams are either tributaries to or occur within a watershed where the rayed bean was known to occur at the time of listing, except for River Raisin. Eight adult rayed bean were detected in the River Raisin in 2015, representing an occurrence in an entirely new watershed that was not known to be occupied at the time of listing. Given that the species is able to live in excess of 20 years, juvenile and adult mussels are immobile, adults mature around age 4 or 5, and the detections were of reproducing adults of unknown ages, it is reasonable to assume that these watersheds were also occupied at the time of listing in 2012 and had not been detected due to lack of survey effort. Thus, we consider all proposed units to have been occupied at the time of listing and appropriate for designation as occupied critical habitat. Furthermore, given that the mussel beds within River Raisin, Oil Creek, Oswayo Creek, and Little Darby Creek are considered currently occupied and fall within the currently extant range for the species ( i.e., wherever found), we would consult on any activities that are occurring or that will occur within these areas of the species' range. (b) Sheepnose: We are proposing to designate critical habitat for the sheepnose in the Chippewa River, Kankakee River, Meramec and Bourbeuse Rivers, Allegheny River, Green River, Tippecanoe River, Walhonding River, Tennessee River, Clinch River, Powell River, and Big Sunflower River (see Proposed Critical Habitat Designation, below). All of these rivers and streams were known to be occupied at the time of listing. (c) Snuffbox: We are proposing to designate critical habitat for the snuffbox in the Wolf River, Embarrass River, Little Wolf River, Grand River (Michigan), Flat River, Clinton River, Huron River, Grand River (Ohio), West Branch Grand River (Ohio), Allegheny River, French Creek, LeBoeuf Creek, Cussewago Creek, Woodcock Creek, Muddy Creek, Conneaut Outlet, West Fork River, Shenango River, Little Shenango River, Middle Island Creek, Meathouse Fork, McElroy Creek, Little Kanawha River, Leading Creek, Hughes River, North Fork Hughes River, South Fork Hughes River, Kanawha River, Elk River (West Virginia), Olentangy River, Little Darby Creek, Big Darby Creek, Stillwater River, Tygarts Creek, Kinniconick Creek, Licking River, Slate Creek, Middle Fork Kentucky River, Red Bird River, Red River, Green River, Salamonie River, Tippecanoe River, Embarras River, Rolling Fork Salt River, Clinch River, Powell River, Paint Rock River, Elk River (Tennessee), Duck River, St. Croix River, Meramec River, Bourbeuse River, St. Francis River, and Spring River (see Proposed Critical Habitat Designation, below). All of these rivers and streams were known to be occupied at the time of listing except for Cussewago Creek, West Fork River, Meathouse Fork, South Fork Hughes River, Leading Creek, and Kanawha River. Although the snuffbox was not reported from or detected in Cussewago Creek (detected in 2011; reported post-listing), West Fork River (detected in 2020), Meathouse Fork (detected in 2001; reported in 2016), South Fork Hughes River (detected in 2001; reported in 2016), Leading Creek (detected in 2017), and Kanawha River (detected in 2017) prior to the snuffbox's listing in 2012, all of the rivers and streams are either tributaries to or occur within the watershed where the snuffbox was known to occur at the time of listing. In Cussewago Creek, a fresh dead adult was detected in 2011, but this observation was not reported to the Service until after the species was listed. In West Fork River, three live adults were found in 2020. In the Meathouse Fork and South Fork Hughes River, live snuffbox were detected in 2001, but the data were not reported to the Service until 2016. Follow up surveys in the South Fork Hughes River in 2017 found live individuals dispersed across 24 miles (39 kilometers) of river. In Leading Creek, although the species was presumed extirpated from this reach at the time of listing, one live individual was detected in 2017. Finally, in the Kanawha River, although the species was thought to be extirpated from this reach at the time of listing, one live individual was detected in 2017. Regarding the Cussewago Creek, Meathouse Fork, and South Fork Hughes River, snuffbox was extant in these areas at the time of listing in 2012; however, these data were not provided to the Service until after the species was listed. Regarding all rivers—including the West Fork River, Leading Creek, and Kanawha River—given that all mussel beds occur within areas that are connected to known occupied areas, the species is known to live in excess of 20 years, juvenile and adult mussels are immobile, adults mature around age 5, and many of these detections were of reproducing adults, it is reasonable to assume that these areas were occupied at the time the species was listed in 2012. As such, we consider all proposed units to be occupied at the time of listing and appropriate for designation as occupied critical habitat. Furthermore, given that the mussel beds within Cussewago Creek, West Fork River, Meathouse Fork, South Fork Hughes River, Leading Creek, and Kanawha River are considered to be currently occupied and fall within the currently extant range for the species ( i.e., wherever found), we would consult on any activities that are occurring or that will occur within these areas of the species' range. (d) Spectaclecase: We are proposing to designate critical habitat for the spectaclecase in the St. Croix River, Mississippi River, Meramec River, Big River, Gasconade River, Big Piney River, Ouachita River, Tennessee River, Clinch River, Nolichucky River, Green River, and Kanawha River (see Proposed Critical Habitat Designation, below). All of these rivers and streams were known to be occupied at the time of listing. When determining proposed critical habitat boundaries, we made every effort to avoid including developed areas such as lands covered by buildings, pavement, and other structures because such lands lack physical or biological features necessary for the rayed bean, sheepnose, snuffbox, and spectaclecase. Critical habitat for these mussels includes only stream channels up to bankfull height, where the stream base flow is contained within the channel. 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 proposed rule have been excluded by text in the proposed rule and are not proposed for designation as critical habitat. Therefore, if the critical habitat is finalized as proposed, 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 physical or biological features in the adjacent critical habitat. The proposed critical habitat designation is defined by the map or maps, as modified by any accompanying regulatory text, presented at the end of this document under Proposed Regulation Promulgation. Proposed Critical Habitat Designation We are proposing approximately 560 river miles (rmi) (902 river kilometers (rkm)) in 15 units as critical habitat for rayed bean; approximately 801 rmi (1,289 rkm) in 11 units as critical habitat for sheepnose; approximately 2,472 rmi (3,979 rkm) in 38 units as critical habitat for snuffbox; and approximately 1,143 rmi (1,839 rkm) in 12 units as critical habitat for spectaclecase. In total, we are proposing to designate approximately 3,974 rmi (6,396 rkm) of unique critical habitat within 76 units across 17 States; many proposed units overlap entirely or within some portion of the proposed units for other species within this proposed rule. All units are considered to be occupied by the species—which are already listed as endangered species under the Act—and all units are occupied by one or more other species already listed under the Act ( i.e., not including the four mussels included in these proposed designations). No unoccupied units are being proposed for any of the four species. All proposed critical habitat units consist of the streambed up to the ordinary high-water mark, as defined at 33 CFR 328.3(c)(4) in the regulations that implement the Clean Water Act (33 U.S.C. 1251 et seq. ). Streambed ownership varies by State and by navigability of the stream. In general, the streambed up to the ordinary high-water mark is public waters of the State; however, there are instances where the streambed is owned by the adjacent landowners. When describing land ownership, below, we use adjacent landownership as a proxy for land ownership that is consistent across the ranges of these species. The critical habitat areas we describe below constitute our current best assessment of areas that meet the definition of critical habitat for all four species. The 15 areas we propose as critical habitat for the rayed bean are: (1) Black River, (2) Pine River, (3) Belle River, (4) River Raisin, (5) Clinton River, (6) Fish Creek, (7) Swan Creek, (8) Blanchard River, (9) Allegheny River, (10) Middle Allegheny River, (11) French Creek, (12) Little Darby Creek, (13) Big Darby Creek, (14) Great Miami River, and (15) Tippecanoe River. Table 2 shows the proposed critical habitat units, identifies the owners by type (Federal, State, local, or private) of land adjacent to each proposed unit, and provides the approximate area of each unit. All proposed units are considered occupied at the time of listing. Table 2—Proposed Critical Habitat Units for Rayed Bean [Length estimates reflect all land within critical habitat unit boundaries] Critical habitat unit Adjacent land ownership type(s) Size of unit in river miles (river kilometers) RABE 1: Black River State, Private 32 (51) RABE 2: Pine River Private 3 (5) RABE 3: Belle River Private 8 (13) RABE 4: River Raisin Local, Private 8 (13) RABE 5: Clinton River Local, Private 8 (13) RABE 6: Fish Creek State, Local, Private 31 (50) RABE 7: Swan Creek Private 4 (7) RABE 8: Blanchard River Local, Private 28 (45) RABE 9: Allegheny River Local, Private 32 (52) RABE 10: Middle Allegheny River Federal, State, Local, Private 169 (272) RABE 11: French Creek Federal, State, Local, Private 100 (161) RABE 12: Little Darby Creek State, Local, Private 21 (35) RABE 13: Big Darby Creek State, Local, Private 38 (60) RABE 14: Great Miami River Private 11 (18) RABE 15: Tippecanoe River State, Local, Private 65 (105) Total 560 (902) Note: Lengths may not sum due to rounding. The 11 areas we propose as critical habitat for the sheepnose are: (1) Lower Chippewa River, (2) Kankakee River, (3) Meramec and Bourbeuse Rivers, (4) Middle Allegheny-Tionesta, (5) Upper Green River, (6) Tippecanoe River, (7) Walhonding River, (8) Lower Tennessee River, (9) Upper Clinch River, (10) Powell River, and (11) Big Sunflower River. Table 3 shows the proposed critical habitat units, identifies the owners by type (Federal, State, local, or private) of land adjacent to each proposed unit, and provides the approximate area of each unit. All proposed units are considered occupied at the time of listing. Table 3—Proposed Critical Habitat Units for Sheepnose [Length estimates reflect all land within critical habitat unit boundaries] Critical habitat unit Adjacent land ownership type(s) Size of unit in river miles (river kilometers) SHNO 1: Lower Chippewa River Federal, State, Local, Private 57 (92) SHNO 2: Kankakee River Federal, State, Local, Private 51 (82) SHNO 3: Meramec and Bourbeuse Rivers State, Local, Private 153 (246) SHNO 4: Middle Allegheny-Tionesta State, Local, Private 28 (45) SHNO 5: Upper Green River Federal, State, Local, Private 157 (253) SHNO 6: Tippecanoe River Federal, State, Local, Private 84 (135) SHNO 7: Walhonding River State, Local, Private 24 (38) SHNO 8: Lower Tennessee River Federal, Private 23 (36) SHNO 9: Upper Clinch River Federal, State, Private 106 (171) SHNO 10: Powell River State, Private 63 (101) SHNO 11: Big Sunflower River Federal, Private 56 (90) Total 801 (1,289) Note: Lengths may not sum due to rounding. The 38 areas we propose as critical habitat for the snuffbox are: (1) Wolf River, (2) Embarrass River, (3) Little Wolf River, (4) Grand River (Michigan), (5) Clinton River, (6) Huron River, (7) Grand River (Ohio), (8) Allegheny River, (9) French Creek, (10) West Fork River, (11) Shenango River, (12) Middle Island Creek, (13) Little Kanawha River, (14) Kanawha River, (15) Olentangy River, (16) Little Darby Creek, (17) Big Darby Creek, (18) Stillwater River, (19) Tygarts Creek, (20) Kinniconick Creek, (21) Licking River, (22) Middle Fork Kentucky River, (23) Red Bird River, (24) Red River, (25) Green River, (26) Salamonie River, (27) Tippecanoe River, (28) Embarras River, (29) Rolling Fork Salt River, (30) Clinch River, (31) Powell River, (32) Paint Rock River, (33) Elk River, (34) Duck River, (35) St. Croix River, (36) Meramec River, (37) St. Francis River, and (38) Spring River. Table 4 shows the proposed critical habitat units, identifies the owners by type (Federal, State, local, or private) of land adjacent to each proposed unit, and provides the approximate area of each unit. All proposed units are considered occupied at the time of listing. Table 4—Proposed Critical Habitat Units for Snuffbox Mussel [Length estimates reflect all land within critical habitat unit boundaries] Critical habitat unit Adjacent land ownership type(s) Size of unit in river miles (river kilometers) SNBO 1: Wolf River Federal, State, Local, Private 8 (13) SNBO 2: Embarrass River Private 18 (29) SNBO 3: Little Wolf River Private 12 (19) SNBO 4: Grand River (Michigan) State, Local, Private 41 (65) SNBO 5: Clinton River Local, Private 8 (13) SNBO 6: Huron River State, Local, Private 16 (26) SNBO 7: Grand River (Ohio) Local, Private 23 (37) SNBO 8: Allegheny River State, Local, Private 35 (57) SNBO 9: French Creek Federal, State, Local, Private 130 (209) SNBO 10: West Fork River Private 22 (35) SNBO 11: Shenango River State, Local, Private 28 (45) SNBO 12: Middle Island Creek Federal, State, Local, Private 87 (140) SNBO 13: Little Kanawha River Federal, State, Local, Private 218 (351) SNBO 14: Kanawha River Local, Private 107 (172) SNBO 15: Olentangy River Federal, State, Local, Private 30 (48) SNBO 16: Little Darby Creek State, Local, Private 21 (35) SNBO 17: Big Darby Creek State, Local, Private 38 (60) SNBO 18: Stillwater River Local, Private 12 (19) SNBO 19: Tygarts Creek State, Private 89 (143) SNBO 20: Kinniconick Creek Private 52 (84) SNBO 21: Licking River Federal, State, Local, Private 239 (385) SNBO 22: Middle Fork Kentucky River Private 13 (21) SNBO 23: Red Bird River Federal, Private 60 (96) SNBO 24: Red River Federal, State, Private 31 (49) SNBO 25: Green River Federal, State, Local, Private 157 (253) SNBO 26: Salamonie River Federal, Private 12 (19) SNBO 27: Tippecanoe River State, Local, Private 65 (105) SNBO 28: Embarras River State, Local, Private 71 (114) SNBO 29: Rolling Fork Salt River Private 95 (153) SNBO 30: Clinch River Federal, State, Local, Private 170 (273) SNBO 31: Powell River State, Private 66 (106) SNBO 32: Paint Rock River Federal, State, Private 53 (85) SNBO 33: Elk River Private 27 (43) SNBO 34: Duck River State, Local, Private 47 (76) SNBO 35: St. Croix River Federal, State, Local, Private 53 (85) SNBO 36: Meramec River State, Local, Private 227 (365) SNBO 37: St. Francis River Federal, State, Private 58 (93) SNBO 38: Spring River State, Private 33 (53) Total 2,472 (3,979) Note: Lengths may not sum due to rounding. The 12 areas we propose as critical habitat for the spectaclecase are: (1) St. Croix River, (2) Mississippi River, (3) Meramec River, (4) Big River, (5) Gasconade River, (6) Big Piney River, (7) Ouachita River, (8) Tennessee River, (9) Clinch River, (10) Nolichucky River, (11) Green River, and (12) Kanawha River. Table 5, below, shows the proposed critical habitat units, identifies the owners by type (Federal, State, local, or private) of land adjacent to each proposed unit, and provides the approximate area of each unit. All proposed units are considered occupied at the time of listing. Table 5—Proposed Critical Habitat Units for Spectaclecase [Length estimates reflect all land within critical habitat unit boundaries] Critical habitat unit Adjacent land ownership types Size of unit in river miles (river kilometers) SPCA 1: Saint Croix Federal, State, Local, Private 53 (86) SPCA 2: Mississippi River Federal, State, Local, Private 132 (213) SPCA 3: Meramec River State, Local, Private 156 (251) SPCA 4: Big River Local, Private 11 (17) SPCA 5: Gasconade River Federal, State, Private 223 (358) SPCA 6: Big Piney River Federal, State, Private 53 (86) SPCA 7: Ouachita River Local, Private 83 (133) SPCA 8: Tennessee River Federal, State, Local, Private 142 (228) SPCA 9: Clinch River Federal, State, Local, Private 160 (257) SPCA 10: Nolichucky River Federal State, Private 37 (60) SPCA 11: Green River Federal, State, Private 77 (125) SPCA 12: Kanawha River Federal, Local, Private 16 (25) Total 1,143 (1,839) Note: Lengths may not sum due to rounding. We present brief descriptions of all units, and reasons why they meet the definition of critical habitat, for the rayed bean, sheepnose, snuffbox, and spectaclecase mussels below. I. Rayed Bean RABE 1: Black River RABE 1 consists of 32 rmi (51 rkm) of the Black River and Mill Creek in St. Clair County, Michigan. The Black River portion of the unit includes 8 rmi (13 rkm) in St. Clair County, Michigan, from the State Highway 136 Bridge (Beard Road Bridge) in Clyde Township downstream to the Wadhams Road Bridge in Kimball Township. This unit also includes 24 rmi (38 rkm) of Mill Creek in St. Clair County, Michigan, from its confluence with Thompson Drain northwest of Brockway Township downstream to its confluence with Black River at Ruby. The unit includes the river channel up to the ordinary high-water mark. Approximately 21.5 percent (7 rmi (11 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (State) ownership, and 78.5 percent (25 rmi (40 rkm)) are in private ownership. Adjacent State lands are owned or managed by the Michigan Department of Natural Resources. RABE 1 is occupied by the species and contains all the physical or biological features essential to the species' conservation. The unit overlaps in part or in full with proposed critical habitat for the proposed endangered salamander mussel ( Simpsonaias ambigua ) (88 FR 57224, August 22, 2023). The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; habitat degradation and loss due to the amount of impervious surface and urbanization; and the presence of invasive species. RABE 2: Pine River RABE 2 consists of 3 rmi (5 rkm) of the Pine River in St. Clair County, Michigan. This unit extends from the confluence of the Pine River and Rattle Run downstream to Newman Road in St. Clair Township (St. Clair County, Michigan). The unit includes the river channel up to the ordinary high-water mark. All of the riparian lands adjacent to, but not included in, this unit are in private ownership. RABE 2 is occupied by the species and contains all the physical or biological features essential to the species' conservation. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; habitat degradation and loss due to the amount of impervious surface and urbanization; and the presence of invasive species. RABE 3: Belle River RABE 3 consists of 8 rmi (13 rkm) of the Belle River in St. Clair County, Michigan. This unit extends from the Westrick Road Bridge downstream to the King Road Bridge in China Township, in St. Clair County, Michigan. The unit includes the river channel up to the ordinary high-water mark. All of the riparian lands adjacent to, but not included in, this unit are in private ownership. RABE 3 is occupied by the species and contains all the physical or biological features essential to the species' conservation. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; habitat degradation and loss due to the amount of impervious surface and urbanization; and the presence of invasive species. RABE 4: River Raisin RABE 4 consists of 8 rmi (13 rkm) of the River Raisin in Lenawee County, Michigan. This unit extends from the Crockett Highway Bridge in Palmyra Township downstream to the U.S. Route 223 Bridge (West Adrian Street) in Blissfield, in Lenawee County, Michigan. The unit includes the river channel up to the ordinary high-water mark. Approximately 3.2 percent (0.3 rmi (0.5 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (local) ownership, and 96.8 percent (8 rmi (13 rkm)) are in private ownership. RABE 4 is occupied by the species and contains all the physical or biological features essential to the species' conservation. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; habitat degradation and loss due to the amount of impervious surface and urbanization; and the presence of invasive species. RABE 5: Clinton River RABE 5 consists of 8 rmi (13 rkm) of the Clinton River in Oakland County, Michigan. This unit extends from downstream of the fish hatchery at Waterford Township downstream to Cass Lake east of Four Towns, in Oakland County, Michigan. The unit includes the river channel up to the ordinary high-water mark. Approximately 11.0 percent (1 rmi (2 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (local) ownership, and 89.0 percent (7 rmi (11 rkm)) are in private ownership. RABE 5 is occupied by the species and contains all the physical or biological features essential to the species' conservation. The unit overlaps in part or in full with proposed critical habitat for the proposed endangered salamander mussel (88 FR 57224; August 22, 2023) and the federally endangered snuffbox mussel. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminant; habitat degradation and loss due to the amount of impervious surface, urbanization, and the lack of canopy cover and vegetative cover in the riparian buffer; lack of connectivity due to barriers; and the presence of invasive species. RABE 6: Fish Creek RABE 6 consists of 31 rmi (50 rkm) of Fish Creek in Steuben and DeKalb Counties, Indiana, and Williams County, Ohio. This unit extends from the Ohio Turnpike Interstate 80/Interstate 90 Bridge in Steuben County, Indiana, downstream to the confluence of Fish Creek with St. Joseph River north of Edgerton in Williams County, Ohio. The unit includes the river channel up to the ordinary high-water mark. Approximately 3.3 percent (1 rmi (2 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (State and local) ownership, and 96.7 percent (30 rmi (48 rkm)) are in private ownership. Adjacent State lands are owned or managed by the Ohio Department of Natural Resources. RABE 6 is occupied by the species and contains all the physical or biological features essential to the species' conservation. The unit overlaps in part or in full with designated critical habitat for the federally threatened rabbitsfoot ( Quadrula cylindrica cylindrica ) (see 50 CFR 17.95(f) and 80 FR 24692, April 30, 2015), and proposed critical habitat for the proposed endangered salamander mussel (88 FR 57224, August 22, 2023). The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; impacts to the hydrological regime; habitat degradation and loss due to agriculture; and the presence of invasive species. RABE 7: Swan Creek RABE 7 consists of 4 rmi (7 rkm) of Swan Creek in Lucas County, Ohio. This unit extends from the Monclova Road Bridge in Maumee downstream to the Ohio Turnpike Interstate 80/Interstate 90 Bridge in Maumee, in Lucas County, Ohio. The unit includes the river channel up to the ordinary high-water mark. All of the riparian lands adjacent to, but not included in, this unit are in private ownership. RABE 7 is occupied by the species and contains all the physical or biological features essential to the species' conservation. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; impacts to the hydrological regime; habitat degradation and loss due to the amount of impervious surface and urbanization; and the presence of invasive species. RABE 8: Blanchard River RABE 8 consists of 28 rmi (45 rkm) of the Blanchard River in Hardin and Hancock Counties, Ohio. This unit extends from the County Road 183 Bridge in Jackson Township (Hardin County, Ohio) downstream to the State Route 568 Bridge (Carey Road Bridge) in Findlay (Hancock County, Ohio). The unit includes the river channel up to the ordinary high-water mark. Approximately 4.3 percent (1 rmi (2 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (local) ownership, and 95.7 percent (27 rmi (43 rkm)) are in private ownership. RABE 8 is occupied by the species and contains all the physical or biological features essential to the species' conservation. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; habitat degradation and loss due to agriculture; and the presence of invasive species. RABE 9: Allegheny River RABE 9 consists of 32 rmi (52 rkm) of the Allegheny River, Olean Creek, Oil Creek, and Oswayo Creek in Allegany and Cattaraugus Counties, New York, and McKean County, Pennsylvania. The Allegheny River portion of this unit includes approximately 13 rmi (21 rkm) of the Allegheny River from its confluence with Oswayo Creek just west of Portville to the Interstate 86 Bridge in Allegany, in Cattaraugus County, New York. The Olean Creek portion of this unit includes 8 rmi (14 rkm) of Olean Creek from its confluence with Oil Creek in Hinsdale downstream to the confluence with Allegheny River in Olean, in Cattaraugus County, New York. The Oil Creek portion of this unit includes 7 rmi (11 rkm) of Oil Creek from the Interstate 86 Bridge near the Cattaraugus County/Allegany County line in New York downstream to its confluence with Olean Creek in Hinsdale (Cattaraugus County, New York). The Oswayo Creek portion of this unit includes 4 rmi (6 rkm) of Oswayo Creek from the Pennsylvania/New York State Line in McKean County, Pennsylvania, and Allegany County, New York, downstream to its confluence with Allegheny River just west of Portville (Cattaraugus County, New York). The unit includes the river channel up to the ordinary high-water mark. Approximately 10.2 percent (3 rmi (5 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (local) ownership, and 89.8 percent (29 rmi (47 rkm)) are in private ownership. RABE 9 is occupied by the species and contains all the physical or biological features essential to the species' conservation. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants and oil and gas extraction; lack of connectivity due to barriers; habitat degradation and loss due to urbanization and agriculture; and the presence of invasive species. RABE 10: Middle Allegheny River RABE 10 consists of 169 rmi (272 rkm) of the Allegheny River in Armstrong, Butler, Clarion, Forest, Venango, and Warren Counties, Pennsylvania. This unit extends from the Kinzua Dam in Warren County, Pennsylvania, downstream to Lock and Dam Number 5 in Armstrong County, Pennsylvania. The unit includes the river channel up to the ordinary high-water mark. Approximately 24.6 percent (42 rmi (68 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (Federal, State, and local) ownership, and 75.4 percent (128 rmi (206 rkm)) are in private ownership. Adjacent Federal lands are owned or managed by the U.S. Forest Service and the Service. Adjacent State lands are owned or managed by the Pennsylvania Bureau of Forestry and the Pennsylvania Game Commission. RABE 10 is occupied by the species and contains all the physical or biological features essential to the species' conservation. The unit overlaps in part or in full with designated critical habitat for the federally threatened longsolid ( Fusconaia subrotunda ) (see 50 CFR 17.95(f) and 88 FR 14794, March 9, 2023) and the federally threatened rabbitsfoot (see 50 CFR 17.95(f) and 80 FR 24692, April 30, 2015), and proposed critical habitat for the proposed endangered salamander mussel (88 FR 57224, August 22, 2023), the federally endangered sheepnose, and the federally endangered snuffbox. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; lack of connectivity due to barriers; habitat degradation and loss due to urbanization and agriculture; and the presence of invasive species. RABE 11: French Creek RABE 11 consists of 100 rmi (161 rkm) of French Creek, LeBoeuf Creek, Muddy Creek, and Cussewago Creek in Crawford, Erie, Mercer, and Venango Counties, Pennsylvania. The French Creek portion of this unit includes 77 rmi (124 rkm) of French Creek from the Union City Reservoir Dam northeast of Union City (Erie County, Pennsylvania) downstream to its confluence with the Allegheny River near Franklin (Venango County, Pennsylvania). The LeBoeuf Creek portion of this unit includes 3 rmi (5 rkm) of LeBoeuf Creek from the State Highway 97 Bridge in Waterford Township downstream to its confluence with French Creek in Leboeuf Township, in Erie County, Pennsylvania. The Muddy Creek portion of this unit includes 14 rmi (23 rkm) of Muddy Creek from Pennsylvania Highway 77 near Little Cooley downstream to its confluence with French Creek east of Cambridge Springs, in Crawford County, Pennsylvania. The Cussewago Creek portion of this unit includes 6 rmi (10 rkm) of Cussewago Creek from the Rogers Ferry Road Bridge in Hayfield Township downstream to its confluence with French Creek in Meadville, in Crawford County, Pennsylvania. The unit includes the river channel up to the ordinary high-water mark. Approximately 17.3 percent (17 rmi (27 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (Federal, State, and local) ownership, and 82.7 percent (83 rmi (134 rkm)) are in private ownership. Adjacent Federal lands are owned or managed by the Service. Adjacent State lands are owned or managed by the Pennsylvania Game Commission. RABE 11 is occupied by the species and contains all the physical or biological features essential to the species' conservation. The unit overlaps in part or in full with designated critical habitat for the federally threatened longsolid (see 50 CFR 17.95(f) and 88 FR 14794, March 9, 2023) and the federally threatened rabbitsfoot (see 50 CFR 17.95(f) and 80 FR 24692, April 30, 2015), and proposed critical habitat for the proposed endangered salamander mussel (88 FR 57224; August 22, 2023), the federally endangered sheepnose, and the federally endangered snuffbox mussel. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; oil and gas development; habitat degradation and loss due to urbanization and agriculture; the presence of invasive species; and the loss of riparian buffer zones. RABE 12: Little Darby Creek RABE 12 consists of 21 rmi (35 rkm) of Little Darby Creek in Madison and Union Counties, Ohio. This unit extends from the Ohio Highway 161 Bridge near Chuckery (Union County, Ohio) downstream to the U.S. Highway 40 Bridge near West Jefferson (Madison County, Ohio). The unit includes the river channel up to the ordinary high-water mark. Approximately 19.6 percent (4 rmi (7 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (State and local) ownership, and 80.4 percent (17 rmi (28 rkm)) are in private ownership. Adjacent State lands are owned or managed by the Ohio Department of Natural Resources. RABE 12 is occupied by the species and contains all the physical or biological features essential to the species' conservation. The unit in part or in full overlaps with designated critical habitat for the federally threatened rabbitsfoot (see 50 CFR 17.95(f) and 80 FR 24692, April 30, 2015) and proposed critical habitat for the federally endangered snuffbox mussel. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; habitat degradation and loss due to urbanization and row crop agriculture; and the presence of invasive species. RABE 13: Big Darby Creek RABE 13 consists of 38 rmi (60 rkm) of Big Darby Creek in Franklin, Madison, and Union Counties, Ohio. This unit extends from the Highway 36 Bridge in Milford Center (Union County, Ohio) downstream to the State Route 665 Bridge (London Groveport Road) by Darbydale (Franklin County, Ohio). The unit includes the river channel up to the ordinary high-water mark. Approximately 36.8 percent (14 rmi (22 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (State and local) ownership, and 63.2 percent (24 rmi (38 rkm)) are in private ownership. Big Darby Creek is a State Scenic River, and adjacent State lands are owned or managed by the Ohio Department of Natural Resources. RABE 13 is occupied by the species and contains all the physical or biological features essential to the species' conservation. The unit overlaps in part or in full with proposed critical habitat for the federally endangered snuffbox mussel. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; habitat degradation and loss due to urbanization and row crop agriculture; lack of connectivity due to a barrier; and the presence of invasive species. RABE 14: Great Miami River RABE 14 consists of approximately 11 rmi (18 rkm) of the Great Miami River in Logan and Shelby Counties, Ohio. This unit extends from the dam at Riverside Park in Quincy (Logan County, Ohio) downstream to the Route 47 Bridge (Riverside Drive) in Sidney (Shelby County, Ohio). The unit includes the river channel up to the ordinary high-water mark. All of the riparian lands adjacent to, but not included in, this unit are in private ownership. RABE 14 is occupied by the species and contains all the physical or biological features essential to the species' conservation. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; habitat degradation and loss due to urbanization and row crop agriculture; lack of connectivity due to barriers; and the presence of invasive species. RABE 15: Tippecanoe River RABE 15 consists of 65 rmi (105 rkm) of the Tippecanoe River in Carroll, Pulaski, Tippecanoe, and White Counties, Indiana. The unit extends from the State Highway 14 Bridge near Winamac (Pulaski County, Indiana) downstream to the confluence of the Tippecanoe River with the Wabash River northeast of Battle Ground (Tippecanoe County, Indiana), excluding Lakes Shafer and Freeman and the stream reach between the two lakes. The unit includes the river channel up to the ordinary high-water mark. Approximately 5.1 percent (3 rmi (5 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (State and local) ownership, and 94.9 percent (62 rmi (100 rkm)) are in private ownership. Adjacent State lands are owned or managed by the Indiana Department of Natural Resources. RABE 15 is occupied by the species and contains all the physical or biological features essential to the species' conservation. The unit overlaps in part or in full with designated critical habitat for the federally threatened rabbitsfoot (see 50 CFR 17.95(f) and 80 FR 24692, April 30, 2015) and the federally threatened round hickorynut (see 50 CFR 17.95(f) and 88 FR 14794; March 9, 2023), and proposed critical habitat for the proposed endangered salamander mussel (88 FR 57224, August 22, 2023), the federally endangered sheepnose, and the federally endangered snuffbox mussel. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; habitat degradation and loss due to urbanization and agriculture; lack of connectivity due to barriers; and the presence of invasive species. II. Sheepnose SHNO 1: Lower Chippewa River SHNO 1 consists of 57 rmi (92 rkm) of the lower Chippewa River in Buffalo, Dunn, Eau Claire, and Pepin Counties, Wisconsin. This unit extends from the confluence of the lower Chippewa River with the Eau Clair River (Eau Claire County, Wisconsin), downstream to its confluence with the Mississippi River (Buffalo/Pepin Counties, Wisconsin). The unit includes the river channel up to the ordinary high-water mark. Approximately 63.0 percent (36 rmi (58 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (Federal, State, and local) ownership, and 37.0 percent (21 rmi (34 rkm)) are in private ownership. Adjacent Federal lands are owned or managed by the Service as part of the Upper Mississippi River National Wildlife Refuge, and adjacent State lands are owned or managed by the Wisconsin Department of Natural Resources. SHNO 1 is occupied by the species and contains all the physical and biological features essential to the species' conservation. This unit overlaps in part or in full with proposed critical habitat for the proposed endangered salamander mussel (88 FR 57224; August 22, 2023). The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants and lack of connectivity due to barriers. SHNO 2: Kankakee River SHNO 2 consists of 51 rmi (82 rkm) of the Kankakee River in Grundy, Kankakee, and Will Counties, Illinois. This unit extends from the confluence of the Kankakee River with West Creek (Kankakee County, Illinois) downstream to its confluence with the Illinois River (Grundy County, Illinois). The unit includes the river channel up to the ordinary high-water mark. Approximately 54.9 percent (28 rmi (45 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (Federal, State, and local) ownership, and 45.1 percent (23 rmi (37 rkm)) are in private ownership. Adjacent Federal lands are owned or managed by the U.S. Forest Service, and adjacent State lands are owned or managed by the Illinois Department of Natural Resources. SHNO 2 is occupied by the species and contains all the physical and biological features essential to the species' conservation. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants and sedimentation, and in-stream gravel mining. SHNO 3: Meramec and Bourbeuse Rivers SHNO 3 consists of 153 rmi (246 rkm) of the Meramec and Bourbeuse Rivers in Franklin, Jefferson, and Saint Louis Counties, Missouri. This unit consists of 90 rmi (145 rkm) of the Meramec River from its confluence with Rye Creek (Franklin County, Missouri) downstream to its confluence with Mississippi River (Jefferson County, Missouri). SHNO 3 also includes 63 rmi (101 rkm) of the Bourbeuse River from its confluence with Little Creek downstream to its confluence with Meramec River, in Franklin County, Missouri. The unit includes the river channel up to the ordinary high-water mark. Approximately 23.7 percent (36 rmi (58 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (State and local) ownership, and 76.3 percent (117 rmi (188 rkm)) are in private ownership. Adjacent State lands are owned or managed by the Missouri Department of Conservation and Missouri Department of Natural Resources. SHNO 3 is occupied by the species and contains all the physical and biological features essential to the species' conservation. This unit overlaps in part or in full with proposed critical habitat for the federally endangered snuffbox, and the federally endangered spectaclecase. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; lack of connectivity due to barriers; the presence of invasive species; loss of riparian zones; and habitat degradation and loss due to urbanization. SHNO 4: Middle Allegheny-Tionesta SHNO 4 consists of 28 rmi (45 rkm)) of the Allegheny River in Forest and Venango Counties, Pennsylvania. This units extends from the confluence of the Allegheny River with Tionesta Creek (Forest County, Pennsylvania) downstream to its confluence with French Creek (Venango County, Pennsylvania). The unit includes the river channel up to the ordinary high-water mark. Approximately 0.14 percent (0.04 rmi (0.06 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (State and local) ownership, and 99.86 percent (28 rmi (45 rkm)) are in private ownership. Adjacent State lands are owned or managed by the Pennsylvania Fish and Boat Commission. SHNO 4 is occupied by the species and contains all the physical and biological features essential to the species' conservation. The unit overlaps in part or in full with designated critical habitat for the federally threatened longsolid (see 50 CFR 17.95(f) and 88 FR 14794; March 9, 2023) and the federally threatened rabbitsfoot (see 50 CFR 17.95(f) and 80 FR 24692, April 30, 2015), and proposed critical habitat for the federally endangered rayed bean. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants and oil and gas extraction; lack of connectivity due to barriers; habitat degradation and loss due to urbanization and agriculture; and the presence of invasive species. SHNO 5: Upper Green SHNO 5 consists of 157 rmi (253 rkm) of the Green River in Butler, Edmonson, Green, Hart, Taylor, and Warren Counties, Kentucky. This unit extends from the confluence of the Green River with the Barren River (Taylor County, Kentucky) downstream to the Green River Dam (Butler County, Kentucky). The unit includes the river channel up to the ordinary high-water mark. Approximately 22.5 percent (35 rmi (56 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (Federal, State, and local) ownership, and 77.5 percent (122 rmi (196 rkm)) are in private ownership. Adjacent Federal lands are owned or managed by the U.S. Army Corps of Engineers and the National Park Service, and adjacent State lands are owned or managed by the Kentucky Department of Agriculture and the Kentucky Division of Water—Wild Rivers Program. SHNO 5 is occupied by the species and contains all the physical and biological features essential to the species' conservation. The unit overlaps in full or in part with designated critical habitat for the federally endangered diamond darter ( Crystallaria cincotta ) (see 50 CFR 17.95(e) and 78 FR 52364, August 22, 2013), the federally threatened longsolid and the federally threatened round hickorynut (see 50 CFR 17.95(f) and 88 FR 14794, March 9, 2023), and the federally threatened rabbitsfoot (see 50 CFR 17.95(f) and 80 FR 24692, April 30, 2015), and proposed critical habitat for the federally endangered snuffbox, and the federally endangered spectaclecase. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of habitat and water quality from impoundments and associated cold water discharges; siltation and pollution due to improper timbering and agricultural practices; resource extraction; water withdrawals; and development. SHNO 6: Tippecanoe River SHNO 6 consists of 84 rmi (135 rkm) of the Tippecanoe River in Fulton, Marshall, Pulaski, Starke, and White Counties, Indiana. This unit extends from the confluence of the Tippecanoe River with Outlet Creek (Marshall County, Indiana) downstream to Lake Freeman (White County, Indiana). The unit includes the river channel up to the ordinary high-water mark. Approximately 10.35 percent (9 rmi (14 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (Federal, State, and local) ownership, and 89.65 percent (75 rmi (121 rkm)) are in private ownership. Adjacent Federal lands are owned or managed by the U.S. Department of Agriculture's Natural Resources Conservation Service (NRCS), and adjacent State lands are owned or managed by the Indiana Department of Natural Resources. SHNO 6 is occupied by the species and contains all the physical and biological features essential to the species' conservation. The unit overlaps in part or in full with designated critical habitat for the federally threatened rabbitsfoot (see 50 CFR 17.95(f) and 80 FR 24692, April 30, 2015) and the federally threatened round hickorynut (see 50 CFR 17.95(f) and 88 FR 14794; March 9, 2023), and proposed critical habitat for the proposed endangered salamander mussel (88 FR 57224, August 22, 2023), the federally endangered rayed bean, and the federally endangered snuffbox mussel. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; habitat degradation and loss due to urbanization and agriculture; lack of connectivity due to barriers; and the presence of invasive species. SHNO 7: Walhonding River SHNO 7 consists of 24 rmi (38 rkm) of the Walhonding River in Coshocton County, Ohio. This units extends from the confluence of the Kokosing River and the Mohican River at Walhonding downstream to the confluence of the Walhonding River with the Tuscarawas River, in Coshocton County, Ohio. The unit includes the river channel up to the ordinary high-water mark. Approximately 4.9 percent (1 rmi (2 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (State and local) ownership, and 95.1 percent (22 rmi (36 rkm)) are in private ownership. Adjacent State lands are owned or managed primarily by the Ohio Department of Natural Resources. SHNO 7 is occupied by the species and contains all the physical and biological features essential to the species' conservation. The unit overlaps in part or in full with designated critical habitat for the federally threatened rabbitsfoot (see 50 CFR 17.95(f) and 80 FR 24692, April 30, 2015). The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants, oil and gas extraction, and agriculture. SHNO 8: Lower Tennessee River SHNO 8 consists of 23 rmi (36 rkm) of the Tennessee River in Livingston, Marshall, and McCracken Counties, Kentucky. This unit extends from the Kentucky Dam (Marshall/Livingston Counties, Kentucky) downstream to the confluence of the lower Tennessee River with the Ohio River (McCracken County, Kentucky). The unit includes the river channel up to the ordinary high-water mark. Approximately 1.8 percent (0.4 rmi (0.6 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (Federal) ownership, and 98.2 percent (22 rmi (35 rkm)) are in private ownership. Adjacent Federal lands are managed by the NRCS. SHNO 8 is occupied by the species and contains all the physical and biological features essential to the species' conservation. The unit overlaps in part or in full with designated critical habitat for the federally threatened rabbitsfoot (see 50 CFR 17.95(f) and 80 FR 24692, April 30, 2015). The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to in-stream gravel mining; degradation and loss of habitat due to dredging; lack of connectivity due to barriers; and the presence of invasive species. SHNO 9: Upper Clinch River SHNO 9 consists of 106 rmi (171 rkm) of the Clinch River in Russell, Scott, and Wise Counties, Virginia, and Hancock County, Tennessee. This unit extends from the confluence of the upper Clinch River with Thompson Creek (Russell County, Virginia) downstream to its confluence with Big Creek (Hancock County, Tennessee). The unit includes the river channel up to the ordinary high-water mark. Approximately 6.1 percent (6 rmi (9 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (Federal and State) ownership, and 93.9 percent (100 rmi (161 rkm)) are in private ownership. Adjacent Federal lands are owned or managed by the U.S. Forest Service, and adjacent State lands are owned or managed by the Tennessee Wildlife Resources Agency or the Virginia Department of Conservation and Recreation. SHNO 9 is occupied by the species and contains all the physical and biological features essential to the species' conservation. The unit overlaps in part or in full with designated critical habitat for the federally endangered Cumberlandian combshell ( Epioblasma brevidens ), the federally endangered oyster mussel ( Epioblasma capsaeformis ), the federally endangered purple bean ( Villosa perpurpurea ), and the federally endangered rough rabbitsfoot ( Quadrula cylindrica strigillata ) (see 50 CFR 17.95(f) and 69 FR 53136, August 31, 2004); the federally threatened longsolid (see 50 CFR 17.95(f) and 88 FR 14794, March 9, 2023); the federally threatened slender chub ( Erimystax cahni ) and the federally threatened yellowfin madtom ( Noturus flavipinnis ) (see 50 CFR 17.95(e) and 42 FR 45526, September 9, 1977); and proposed critical habitat for the proposed endangered salamander mussel (88 FR 57224, August 22, 2023); the federally endangered rayed bean; the federally threatened sickle darter ( Percina williamsi ) (88 FR 4128; January 24, 2023); the federally endangered snuffbox; and the federally endangered spectaclecase. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of habitat and water quality from downstream impoundment, mining discharges, siltation, contaminants, oil and gas extraction, and water withdrawals; urbanization; and the presence of invasive species. SHNO 10: Powell River SHNO 10 consists of 63 rmi (101 rkm) of the Powell River in Lee County, Virginia, and Claiborne and Hancock County, Tennessee. This unit extends from the confluence of the Powell River with Little Yellow Branch (Lee County, Virginia) downstream to Highway 25E (Dixie Highway E) (Claiborne County, Tennessee). The unit includes the river channel up to the ordinary high-water mark. Approximately 0.5 percent (0.3 rmi (0.5 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (State) ownership, and 99.5 percent (62 rmi (100 rkm)) are in private ownership. Adjacent State lands are owned or managed by the Tennessee Department of Environment and Conservation or the Virginia Department of Conservation and Recreation. SHNO 10 is occupied by the species and contains all the physical and biological features essential to the species' conservation. This unit overlaps in part or in full with designated critical habitat for the federally endangered Cumberlandian combshell, federally endangered oyster mussel, federally endangered purple bean, and federally endangered rough rabbitsfoot (see 50 CFR 17.95(f) and 69 FR 53136, August 31, 2004); and the federally threatened slender chub and federally threatened yellowfin madtom (see 50 CFR 17.95(e) and 42 FR 45526, September 9, 1977); and proposed critical habitat for the federally endangered snuffbox. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants, urbanization, oil and gas extraction, agriculture, and coal mining and mine runoff; lack of connectivity due to barriers; the presence of invasive species; and changes to the hydrological regime. SHNO 11: Big Sunflower River SHNO 11 consists of 56 rmi (90 rkm) of the Big Sunflower River in Bolivar and Sunflower Counties, Mississippi. This unit begins where Merigold-Drew Road crosses the Big Sunflower River (Bolivar County, Mississippi) and extends downstream to the confluence of the Big Sunflower River with the Quiver River (Sunflower County, Mississippi). The unit includes the river channel up to the ordinary high-water mark. Approximately 4.1 percent (2 rmi (4 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (Federal) ownership, and 95.9 percent (54 rmi (86 rkm)) are in private ownership. Adjacent Federal lands are owned or managed by the NRCS. SHNO 11 is occupied by the species and contains all the physical and biological features essential to the species' conservation. The unit overlaps in part or in full with designated critical habitat for the federally threatened rabbitsfoot (see 50 CFR 17.95(f) and 80 FR 24692, April 30, 2015). The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants, sedimentation, and agriculture; degradation and loss of habitat due to dredging; and changes to the hydrological regime. III. Snuffbox SNBO 1: Wolf River SNBO 1 consists of 8 rmi (13 rkm) of the Wolf River in Shawano County, Wisconsin. This unit extends from the Shawano Dam downstream to the County Road CCC Bridge near the town of Waukechon, in Shawano County, Wisconsin. The unit includes the river channel up to the ordinary high-water mark. Approximately 17.0 percent (1 rmi (2 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (Federal, State, and local) ownership, and 83.0 percent (7 rmi (11 rkm)) are in private ownership. Adjacent Federal land is owned or managed by the Bureau of Land Management. Adjacent State lands are owned or managed by the Wisconsin Department of Natural Resources. SNBO 1 is occupied by the species and contains all the physical and biological features essential to the species' conservation. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; habitat degradation and loss due to urbanization; lack of connectivity due to barriers; impacts to the hydrological regime; and the presence of invasive species. SNBO 2: Embarrass River SNBO 2 consists of 18 rmi (29 rkm) of the Embarrass River, South Branch Embarrass River, and North Branch Embarrass River in Shawano County, Wisconsin. This unit includes approximately 5 rmi (7 rkm) of the Embarrass River and extends from the Caroline Dam in Grant downstream to its confluence with North Branch Embarrass River, in Shawano County, Wisconsin. The South Branch Embarrass River portion of this unit includes approximately 12 rmi (19 rkm) of the South Branch Embarrass River and extends from Spaulding Street (County Road M) in Tigerton downstream to its confluence with Embarrass River in Grant, in Shawano County, Wisconsin. The North Branch Embarrass River portion of this unit includes approximately 2 rmi (3 rkm) of North Branch Embarrass from the dam in Leopolis downstream to its confluence with Embarrass River, in Shawano County, Wisconsin. The unit includes the river channel up to the ordinary high-water mark. All of the riparian lands adjacent to, but not included in, this unit are in private ownership. SNBO 2 is occupied by the species and contains all the physical and biological features essential to the species' conservation. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; habitat degradation and loss due to urbanization; lack of connectivity due to barriers; impacts to the hydrological regime; and the presence of invasive species. SNBO 3: Little Wolf River SNBO 3 consists of 12 rmi (19 rkm) of the Little Wolf River in Waupaca County, Wisconsin. This unit extends from the Manawa Mill Pond Dam in Manawa downstream to the Highway X Bridge in Mukwa, in Waupaca County, Wisconsin. The unit includes the river channel up to the ordinary high-water mark. All of the riparian lands adjacent to, but not included in, this unit are in private ownership. SNBO 3 is occupied by the species and contains all the physical and biological features essential to the species' conservation. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; habitat degradation and loss due to urbanization; lack of connectivity due to barriers; impacts to the hydrological regime; and the presence of invasive species. SNBO 4: Grand River (Michigan) SNBO 4 consists of 41 rmi (65 rkm) of the Grand River and the Flat River in Ionia and Kent Counties, Michigan. The Grand River portion of this unit includes 40 rmi (64 rkm) of the Grand River and extends from the Webber Dam upstream of Lyons (Ionia County, Michigan) downstream to its confluence with Thornapple River in Ada (Kent County, Michigan). The Flat River portion of this unit includes 0.5 rmi (0.8 rkm) of the Flat River from West State Highway 21 in Lowell downstream to its confluence with Grand River in Lowell, in Kent County, Michigan. The unit includes the river channel up to the ordinary high-water mark. Approximately 33.5 percent (14 rmi (22 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (State and local) ownership, and 66.5 percent (27 rmi (43 rkm)) are in private ownership. Adjacent State lands are owned or managed by the Michigan Department of Natural Resources. SNBO 4 is occupied by the species and contains all the physical and biological features essential to the species' conservation. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; habitat degradation and loss due to urbanization; lack of connectivity due to barriers; and the presence of invasive species. SNBO 5: Clinton River SNBO 5 consists of 8 rmi (13 rkm) of the Clinton River in Oakland County, Michigan. This unit extends from downstream of the fish hatchery at Waterford Township downstream to Cass Lake east of Four Towns, in Oakland County, Michigan. The unit includes the river channel up to the ordinary high-water mark. Approximately 11.0 percent (0.9 rmi (1 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (local) ownership, and 89.0 percent (7 rmi (12 rkm)) are in private ownership. SNBO 5 is occupied by the species and contains all the physical and biological features essential to the species' conservation. The unit overlaps in part or in full with proposed critical habitat for the proposed endangered salamander mussel (88 FR 57224; August 22, 2023) and the federally endangered rayed bean. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; habitat degradation and loss due to the amount of impervious surface, urbanization, and the lack of canopy cover and vegetative cover in the riparian buffer; lack of connectivity due to barriers; and the presence of invasive species. SNBO 6: Huron River SNBO 6 consists of 16 rmi (26 rkm) of the Huron River in Livingston County, Michigan. This unit extends from Strawberry Lake downstream to the Kent Lake Dam, in Livingston County, Michigan. The unit includes the river channel up to the ordinary high-water mark. Approximately 55.5 percent (9 rmi (14 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (State and local) ownership, and 44.5 percent (7 rmi (11 rkm)) are in private ownership. Adjacent State lands are owned or managed by the Michigan Department of Natural Resources. SNBO 6 is occupied by the species and contains all the physical or biological features essential to the species' conservation. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants; lack of connectivity due to barriers; and the presence of invasive species. SNBO 7: Grand River (Ohio) SNBO 7 consists of 23 rmi (37 rkm) of the Grand River in Ashtabula and Lake Counties, Ohio. This unit extends from the Harpersfield Dam in Harpersfield (Ashtabula County, Ohio) downstream to the Norfolk and Western Railroad Trestle (Lake County, Ohio). The unit includes the river channel up to the ordinary high-water mark. Approximately 33.1 percent (8 rmi (12 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (local) ownership, and 66.9 percent (16 rmi (25 rkm)) are in private ownership. SNBO 7 is occupied by the species and contains all the physical or biological features essential to the species' conservation. This unit overlaps in part or in full with designated critical habitat for the federally threatened round hickorynut (see 50 CFR 17.95(f) and 88 FR 14794, March 9, 2023). The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of habitat and water quality from impoundments, domestic and industrial pollution due to human development, resource extraction, water withdrawals, and wastewater treatment plants; and the presence of invasive species. SNBO 8: Allegheny River SNBO 8 consists of 35 rmi (57 rkm) of the Allegheny River in Venango County, Pennsylvania. This unit extends from the Allegheny River's confluence with French Creek near Franklin downstream to Interstate 80 near Emlenton, in Venango County, Pennsylvania. The unit includes the river channel up to the ordinary high-water mark. Approximately 18.6 percent (6 rmi (11 rkm)) of the riparian lands adjacent to, but not included in, this unit are in public (State and local) ownership, and 81.4 percent (29 rmi (46 rkm)) are in private ownership. Adjacent State lands are owned or managed by the Pennsylvania Bureau of Forestry and the Pennsylvania Fish and Boat Commission. SNBO 8 is occupied by the species and contains all the physical or biological features essential to the species' conservation. The unit overlaps in part or in full with designated critical habitat for the federally threatened longsolid (see 50 CFR 17.95(f) and 88 FR 14794; March 9, 2023) and the federally threatened rabbitsfoot (see 50 CFR 17.95(f) and 80 FR 24692, April 30, 2015), and proposed critical habitat for the federally endangered rayed bean and the federally endangered sheepnose. The features essential to the conservation of this species may require special management considerations or protection to reduce the following threats: degradation of water quality due to contaminants and row crop agriculture; lack of connectivity due to barriers ( e.g., locks and dams); oil and gas development; channelization; and the presence of invasive species. SNBO 9: French Creek SNBO 9 consists of 130 rmi (209 rkm) of French Creek, West Branch French Creek, LeBoeuf Creek, Cussewago Creek, Woodcock Creek, Muddy Creek, and Conneaut Outlet in Erie, Crawford, Lebanon, Mercer, and Venango Counties, Pennsylvania. The French Creek portion of this unit includes 75 rmi (121 rkm) from the Union City Reservoir Dam northeast of Union City (Erie County, Pennsylvania) downstream to its confluence with Allegheny River near Franklin (Venan [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%3A2024-28316. Public record. Not legal advice.