98-5193. Endangered and Threatened Wildlife and Plants; Decision on Designation of Critical Habitat for the Gulf Sturgeon  

  • [Federal Register Volume 63, Number 39 (Friday, February 27, 1998)]
    [Rules and Regulations]
    [Pages 9967-9974]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 98-5193]
    
    
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    DEPARTMENT OF COMMERCE
    
    National Oceanic and Atmospheric Administration
    
    50 CFR Part 226
    
    DEPARTMENT OF THE INTERIOR
    
    Fish and Wildlife Service
    
    50 CFR Part 17
    
    
    Endangered and Threatened Wildlife and Plants; Decision on 
    Designation of Critical Habitat for the Gulf Sturgeon
    
    AGENCIES: National Marine Fisheries Service, National Oceanic and 
    Atmospheric Administration, Commerce; and Fish and Wildlife Service, 
    Interior.
    
    ACTION: Notice of decision on critical habitat designation.
    
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    SUMMARY: The National Marine Fisheries Service (NMFS) and the Fish and 
    Wildlife Service (FWS), collectively the Services, announce a decision 
    on designation of critical habitat for the Gulf sturgeon (Acipenser 
    oxyrinchus desotoi), a federally listed threatened species pursuant to 
    the Endangered Species Act of 1973, as amended. Based on lack of 
    benefit to the species, the Services have determined that critical 
    habitat designation is not prudent. This constitutes the Services' not 
    prudent finding for the designation of critical habitat for the Gulf 
    sturgeon.
    
    DATES: The finding announced in this notice was made on February 24, 
    1998.
    
    ADDRESSES: Information, comments, or questions should be submitted to 
    the Field Supervisor, U.S. Fish and Wildlife Service, 6620 Southpoint 
    Drive South, Suite 310, Jacksonville, Florida 32216; or the Regional 
    Director, U.S. Department of Commerce, National Marine Fisheries 
    Service, 9721 Executive Center Drive N., St. Petersburg, Florida 33702. 
    The administrative record supporting this decision is available for 
    public inspection, by appointment, during normal business hours at the 
    above addresses.
    
    FOR FURTHER INFORMATION CONTACT: Dr. Michael M. Bentzien, Assistant 
    Field Supervisor, FWS, see ADDRESSES section above or telephone 904/
    232-2580, extension 106; or Ms. Colleen Coogan, NMFS, see ADDRESSES 
    section above or telephone 813/570-5312.
    
    SUPPLEMENTARY INFORMATION:
    
    Background
    
        The Gulf sturgeon (Acipenser oxyrinchus (=oxyrhynchus) desotoi), 
    also known as the Gulf of Mexico sturgeon, is a nearly cylindrical fish 
    with an extended snout, ventral mouth, chin barbels, and with the upper 
    lobe of the tail longer than the lower. Adults range from 1.8 to 2.4 
    meters (m) (6 to 8 feet (ft)) in length, with adult females larger than 
    males. It is a subspecies of Atlantic sturgeon, Acipenser oxyrinchus 
    (=oxyrhynchus), and is distinguished from Acipenser oxyrinchus 
    oxyrinchus, the East Coast subspecies, by its longer head, pectoral 
    fins, and spleen. The Gulf sturgeon is restricted to the Gulf of Mexico 
    and its drainages, primarily from the Mississippi River to the Suwannee 
    River, within the States of Louisiana, Mississippi, Alabama, and 
    Florida. Sporadic occurrences are known as far west as Texas (Rio 
    Grande), and marine waters in Florida south to Florida Bay (Wooley and 
    Crateau 1985, Reynolds 1993). An anadromous species, the Gulf sturgeon 
    migrates between fresh and salt water.
        The Services' involvement with the Gulf sturgeon began with 
    monitoring and other studies of the Apalachicola River population by 
    the FWS Panama City, Florida, Fisheries Assistance Office in 1979. The 
    fish was included as a category 2 species in the FWS December 30, 1982 
    (47 FR 58454) and September 18, 1985 (50 FR 37958) vertebrate review 
    notices and in the January 6, 1989 (54 FR 554) animal notice of review. 
    Category 2 designation was given at that time to species for which 
    listing as threatened or endangered was possibly appropriate, but for 
    which additional biological information was needed to support a 
    proposed rule. In 1980, the FWS Jacksonville, Florida, Office 
    contracted a status survey report on the Gulf sturgeon (Hollowell 
    1980). The report concluded that the fish had been reduced to a small 
    population due to overfishing and habitat loss. In 1988, the Panama 
    City Office completed a report (Barkuloo 1988) on the conservation 
    status of the Gulf sturgeon, recommending that the subspecies be listed 
    as a threatened species pursuant to the Act. The Services jointly 
    proposed the Gulf sturgeon for listing as a threatened species on May 
    2, 1990 (55 FR 18357). In that proposed rule, the Service maintained 
    that designation of
    
    [[Page 9968]]
    
    critical habitat was not determinable due to the sturgeon's broad range 
    and the lack of knowledge of specific areas utilized by the subspecies. 
    The final rule for the Gulf sturgeon was published on September 30, 
    1991 (56 FR 49653). It included special rules promulgated under Section 
    4(d) of the Act for a threatened species, allowing taking of Gulf 
    sturgeon in accordance with applicable State laws, for educational and 
    scientific purposes, the enhancement of propagation or survival of the 
    species, zoological exhibition, and other conservation purposes. The 
    final rule found that critical habitat designation ``may be prudent but 
    is not now determinable.'' Further comments on the critical habitat 
    issue were solicited from all interested parties following listing. A 
    final decision on designation of critical habitat was to have been made 
    by May 2, 1992.
        On August 11, 1994, the Sierra Club Legal Defense Fund, Inc. 
    (Fund), on behalf of the Orleans Audubon Society and Florida Wildlife 
    Federation, gave written notice of their intent to file suit against 
    the Department of the Interior for failure to designate critical 
    habitat for the Gulf sturgeon within the statutory time limits 
    established under the Act. The Fund filed suit (Orleans Audubon Society 
    v. Babbitt, Civ. No. 94-3510 (E.D. La)) following a combined meeting 
    and teleconference with the Service on October 11, 1994.
        On August 23, 1995, the Services published a notice of decision (60 
    FR 43721) on critical habitat designation for the Gulf sturgeon. The 
    Services determined that critical habitat designation was not prudent 
    based on the lack of additional conservation benefit to the species.
        On November 23, 1995, the above mentioned plaintiffs again gave 
    notice of their intent to file suit against the Departments of the 
    Interior and Commerce for failing to designate critical habitat for the 
    Gulf sturgeon. On January 31, 1996, the Court denied both the Services' 
    motion to dismiss the suit and the plaintiffs' motion to find the 
    Services in contempt. On October 28, 1997, the Court rejected the 
    plaintiffs' request for a Court order requiring the Services to 
    designate critical habitat. The plaintiffs' motion for summary judgment 
    was granted, with relief restricted to a remand of the matter to the 
    agencies for further consideration based on the best scientific 
    information available.
    
    Critical Habitat Definition and Requirements
    
        Critical habitat is defined in section 3(5)(A) of the Act as ``(i) 
    the specific areas within the geographic area occupied by a species * * 
    * on which are found those physical or biological features (I) 
    essential to the conservation of the species, and (II) that may require 
    special management considerations or protection; and (ii) specific 
    areas outside the geographical area occupied by a species at the time 
    it is listed * * * upon determination by the Secretary that such areas 
    are essential for the conservation of the species.'' The term 
    ``conservation,'' as defined in Section 3(3) of the Act, means ``* * * 
    to use and the use of all methods and procedures which are necessary to 
    bring any endangered or threatened species to the point at which the 
    measures provided pursuant to this Act are no longer necessary,'' i.e., 
    the species is recovered and can be removed from the list of endangered 
    and threatened species. Section 4(a)(3) of the Act requires that 
    critical habitat be designated at the time any species is listed as an 
    endangered or threatened species, to the extent prudent and 
    determinable. If a final regulation listing a species finds that 
    critical habitat is not determinable, a critical habitat designation 
    must be made within one additional year (within two years of the date 
    on which the species was proposed for listing).
        Section 4(b)(2) of the Act requires the Services to consider the 
    economic impact of designating any particular area as critical habitat. 
    The Services' regulations for listing endangered and threatened species 
    and designating critical habitat (50 CFR 424.19) require that, in 
    analyzing such impacts, the Services identify any significant 
    activities that would either affect an area considered for designation 
    as critical habitat or be likely to be affected by the designation, and 
    after proposing the designation for such an area, consider the probable 
    economic and other impacts of the designation upon proposed or ongoing 
    activities. An area may be excluded from critical habitat if it is 
    determined that the economic benefits of such exclusion outweigh the 
    conservation benefits of including the area in critical habitat. 
    Exclusions may not be made if the failure to designate them as critical 
    habitat would result in the extinction of the species concerned. This 
    standard approximates the jeopardy standard of the Act, but may be less 
    stringent because it requires a determination that the exclusion ``* * 
    * will result in the extinction * * *'' rather than more probabilistic 
    criterion ``* * * likely to jeopardize the continued existence * * *'' 
    of section 7(a)(2).
        If no exclusions are made to critical habitat, it should (presuming 
    adequate biological and distributional information is available) 
    include all areas necessary to recover the species. If areas are 
    excluded from critical habitat for economic reasons, final critical 
    habitat designation could range from an area just under that required 
    for recovery to an area barely sufficient to prevent the species' 
    extinction, and insufficient for its recovery. In summary, while the 
    Act defines ``conservation'' to mean recovery of the species, section 
    4(b)(2) does not require the Services to designate critical habitat 
    sufficient for the recovery of the species if economic benefits of 
    excluding certain areas outweigh the conservation benefit to the 
    species from their inclusion.
        In accordance with the definition of critical habitat provided by 
    section 3(5)(A)(i) of the Act, the Services' regulations (50 CFR 
    424.12) require the Services to consider the principal biological or 
    physical features that are essential to the conservation of the 
    species. General requirements of species include, but are not limited 
    to:
        (1) Space for individual and population growth, and for normal 
    behavior;
        (2) Food, water, air, light, minerals, or other nutritional or 
    physiological requirements;
        (3) Cover or shelter;
        (4) Sites for breeding, reproduction, rearing of offspring, 
    germination, or seed dispersal; and generally
        (5) Habitats that are protected from disturbance or are 
    representative of the historic geographical and ecological 
    distributions of a species.
        The regulations further require the Services to focus on principal 
    biological or physical constituent elements within the defined area 
    that are essential to the conservation of the species. Primary 
    constituent elements may include, but are not limited to, roost sites, 
    nesting grounds, spawning sites, seasonal wetland or dryland, water 
    quality or quantity, host species or plant pollinators, geological 
    formation, vegetation type, tide, and specific soil types.
        The regulations state that a designation of critical habitat is not 
    prudent if either of the two following situations exist:
        (1) The species is threatened by taking or other human activity, 
    and identification of critical habitat can be expected to increase the 
    degree of such threat to the species, or
        (2) Such designation of critical habitat would not be beneficial to 
    the species.
        Potential benefits of critical habitat designation derive from 
    section 7(a)(2) of the Act, which requires Federal
    
    [[Page 9969]]
    
    agencies, in consultation with the Service, to ensure that their 
    actions are not likely to jeopardize the continued existence of listed 
    species or to result in the destruction or adverse modification of 
    critical habitat of such species. Implementing regulations (50 CFR 
    402.14) require each Federal agency to review its actions at the 
    earliest possible time to determine whether any action may affect 
    listed species or critical habitat. If a determination is made that a 
    Federal action may adversely affect a listed species a formal 
    consultation is required. All consultations result in a finding of 
    whether or not the proposed action is likely to jeopardize the 
    continued existence of the species, and, if critical habitat is 
    designated, whether the action is likely to destroy or adversely modify 
    critical habitat.
        Critical habitat, by definition, applies only to Federal agency 
    actions. 50 CFR 402.02 defines ``jeopardize the continued existence 
    of'' as meaning to engage in an action that would reasonably be 
    expected, directly or indirectly, to reduce appreciably the likelihood 
    of both the survival and recovery of a listed species in the wild by 
    reducing the reproduction, numbers, or distribution of that species. 
    ``Destruction or adverse modification'' is defined as a direct or 
    indirect alteration that appreciably diminishes the value of critical 
    habitat for both the survival and recovery of a listed species. Such 
    alterations include, but are not limited to, alterations adversely 
    modifying any of those physical or biological features that were the 
    basis for determining the habitat to be critical. Thus, in the section 
    7(a)(2) consultation process, the jeopardy analysis focuses on 
    potential effects on the species' populations, whereas the destruction 
    or adverse modification analysis focuses on habitat value, specifically 
    on those constituent elements identified in the critical habitat 
    listings in 50 CFR 17.95, 17.96 (FWS), or 226 (NMFS). However, either a 
    jeopardy or a destruction or adverse modification biological opinion 
    requires the Services to find an appreciable effect on both the 
    species' survival and recovery.
        Federal actions satisfying the standard for adverse modification 
    are nearly always found to also jeopardize the species concerned, and 
    the existence of critical habitat designation does not materially 
    affect the outcome of consultation. Biological opinions which conclude 
    that a Federal agency action is likely to adversely modify critical 
    habitat but is not likely to jeopardize the species for which it is 
    designated are extremely rare historically; none have been issued in 
    recent years. Such situations might involve a Federal action in 
    critical habitat outside of current range of the species, where the 
    action would not reduce the current reproduction, distribution, or 
    numbers of the species, but would appreciably reduce the value of 
    critical habitat for both survival and recovery. For some highly 
    endangered species whose survival and recovery in its current range was 
    unlikely, and which depended on the expansion of its range and numbers 
    into currently unoccupied habitat, the designation of unoccupied 
    critical habitat may in certain rare instances provide additional 
    protection to that afforded by the jeopardy standard. Since threatened 
    species such as the Gulf sturgeon are, by definition, not currently at 
    risk of extinction, but are rather anticipated to become so in the 
    foreseeable future, unoccupied critical habitat would not be 
    immediately required for their survival.
        It should be noted also that regardless of critical habitat 
    designation, Federal agencies are required by section 7(a)(1) of the 
    Act to utilize their authorities in furtherance of the Act's purposes 
    by carrying out conservation (i.e., recovery) activities for listed 
    species. For no jeopardy (or no destruction or adverse modification) 
    biological opinions, the Services may provide discretionary 
    conservation recommendations to the consulting Federal agency to assist 
    them in this responsibility. Recovery plans also provide guidance on 
    specific tasks that Federal and other agencies can carry out to assist 
    in the recovery of listed species.
    
    Ecology of the Gulf Sturgeon
    
        The Gulf sturgeon is an anadromous species inhabiting the Gulf of 
    Mexico and Gulf Coast rivers from Louisiana to Florida. Adults and 
    subadults spend eight to nine months each year in rivers where they 
    spawn and three to four of the coolest months in estuaries or Gulf 
    waters.
    
    Migration
    
        In Florida, both adults and subadults begin moving from the Gulf of 
    Mexico into the Suwannee and Apalachicola rivers in early spring until 
    early May (Carr 1983, Wooley and Crateau 1985, Odenkirk 1989, Clugston 
    et al. 1995). River water temperatures at that time range from 16.0 
    deg.C to 23.0  deg.C (60.8  deg.F to 75.0  deg.F). Large females 
    apparently prefer migrating upstream in shallow water areas, whereas 
    deep water areas are preferred during downstream or post spawning 
    migrations. This preference does not apply to males (Huff 1975). 
    Downstream migration in the Apalachicola River begins in late September 
    when water temperatures reach about 23.0  deg.C (75.0  deg.F), and 
    extends into November (Wooley and Crateau 1985). During the fall 
    migration from fresh to salt water, Gulf sturgeon in the Apalachicola 
    River enter the Brothers River, a tributary located about 19.2 
    kilometers (km) (12.0 miles (mi)) above the Gulf of Mexico. It is 
    believed that the Brothers River is used as a staging area for Gulf 
    sturgeon to osmoregulate (adjust to changed salinity) prior to entering 
    the Gulf of Mexico. The sturgeon occupy a microhabitat 8.0 to 18.0 m 
    (26.2 to 59.0 ft) in depth with a sand and clay substrate covered with 
    Asiatic clams (Corbicula fluminea) and detritus (Wooley and Crateau 
    1985). The fish remain in the Brothers River for an average of twelve 
    days (Wooley and Crateau 1985, Odenkirk 1989). Very little is known 
    about the estuarine and neritic (shallow coastal waters) habitat use of 
    migrating Gulf sturgeon. Parauka (U.S. Fish and Wildlife Service 1997) 
    found that subadult Gulf sturgeon immigrating from the Choctawhatchee 
    River into the estuarine waters of Choctawhatchee Bay moved generally 
    along the shoreline. Water depths ranged from 2.0 to 7.0 m (6.5 to 23.0 
    ft) with a sand and mud substrate.
    
    Freshwater Habitat
    
        Foster and Clugston (1997) found that telemetered Gulf sturgeon in 
    the Suwannee River were frequently located close to springs throughout 
    the warmest period, but none were located within a spring or the 
    thermal plume emanating from a spring. The substrate of much of the 
    Suwannee River is sand and limerock, especially in those areas near 
    springs and spring runs. Wooley and Crateau (1985) reported that Gulf 
    sturgeon in the Apalachicola River utilized the area immediately 
    downstream from Jim Woodruff Lock and Dam (JWLD) from May through 
    September. The area occupied consisted of the tailrace and spillway 
    basin of JWLD and a large scour hole below the lock. The area consisted 
    of sand and gravel substrate with water depths ranging from 6.0 to 12.0 
    m (19.7 to 39.4 ft). Telemetry studies conducted on Gulf sturgeon in 
    the Choctawhatchee River found that they did not distribute themselves 
    uniformly throughout the river and did not occupy the deepest and 
    coolest water available (Potak et al. 1995). Fish remained within two 
    primary summer holding areas staying outside the main channel where 
    water velocities were less than the maximum available. Most fish were 
    in water depths of 1.5 to 3.0 m (4.9 to 9.9 ft) and substrates were 
    silt or clay. Morrow et
    
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    al. (in press) reported that the lower part of the West Middle River 
    (lower Pearl River system) was an important summer habitat for juvenile 
    and sub-adult Gulf sturgeon. The habitat is characterized with water 
    depths ranging from 9.0 to 19.0 m (29.5 to 62.3 ft) with sluggish flows 
    and a hard substrate of sand and gravel.
    
    Estuarine Habitat
    
        Mason and Clugston (1993) noted that the estuarine seagrass beds 
    with mud and sand substrates appear to be important winter habitats for 
    Gulf sturgeon where most of the feeding is thought to occur. Clugston 
    et al. (1995) reported that the young Gulf sturgeon in the Suwannee 
    River, weighing between 0.3 and 2.5 kilograms (kg) (0.7 to 5.5 pounds 
    (lb)), remained in the vicinity of the river mouth and estuary during 
    the winter and spring. Fox and Hightower (1997) captured adult Gulf 
    sturgeon in the early spring in Choctawhatchee Bay prior to their 
    migration into the Choctawhatchee River. Fish were collected in 
    stationary gill nets set 455.0 m (1,500 ft) from shore at depths of 2.0 
    to 4.0 m (6.5 to 13.0 ft). The bay at that site is about 5.5 km (3.4 
    mi) wide and with depths up to 6.7 m (22.0 ft). Parauka (U.S. Fish and 
    Wildlife Service 1997) collected 6 subadult Gulf sturgeon in the 
    Choctawhatchee River, equipped them with acoustic tags, and monitored 
    their movement in the estuary during the winter. Five of six fish 
    remained in the estuary the entire winter occupying nearshore habitats, 
    1.2 to 4.6 m (4 to 15 ft) in depth with a sand and mud substrate.
    
    Food Habits
    
        Mason and Clugston (1993) reported that in the spring, immigrating 
    subadult and adult Gulf sturgeon collected from the mouth of the 
    Suwannee River contained gammarid, haustoriid, and other maphipods, 
    polychaete and oligochaete annelids, lancelets, and brachiopods. 
    However, once in fresh water, these Gulf sturgeon did not eat as 
    evidenced by the presence of only a greenish-tinged mucus in their guts 
    from June through October. The stomach contents of a 79.5 kg (175 lb) 
    Gulf sturgeon collected in Choctawhatchee Bay during the winter 
    contained adult ghost and commensal shrimp (R. Head, Gulf Coast 
    Research Laboratory, personal communication 1997). Clugston et al. 
    (1995) concluded that Gulf sturgeon appear to gain weight only during 
    the winter and spring while in marine or estuarine waters and lose 
    weight during the eight to nine month period while in fresh water. Carr 
    (1983) reported that marked Gulf sturgeon from the Suwannee River 
    gained up to 30 percent of body weight in one year but showed little or 
    no growth when recaptured during the same season. Wooley and Crateau 
    (1985) noted that Gulf sturgeon 80.0 to 114.0 centimeters (cm) (31.5 to 
    44.9 inches (in)) long that were captured and recaptured in the 
    Apalachicola River during the summer period exhibited weight losses of 
    4 to 15 percent or 0.5 to 2.3 kg (1.1 to 5.1 lb).
    
    River-Specific Fidelity
    
        The results of tagging studies suggest that Gulf sturgeon exhibit a 
    high degree of river fidelity. From 1981 to 1993, 4,100 fish were 
    tagged in the Apalachicola and Suwannee rivers, with 860 fish 
    recaptured in the river of initial collection and only 8 sub-adults 
    exhibiting inter-river movement (Wooley and Crateau 1985, U.S. Fish and 
    Wildlife Service and Gulf States Marine Fisheries Commission 1995, Carr 
    et al. 1996, Foster and Clugston 1997). Foster and Clugston (1997) 
    noted that telemetered Gulf sturgeon in the Suwannee River returned to 
    the same areas as the previous summer suggesting that chemical cuing 
    may influence distribution. Wooley and Crateau (1985) indicate that the 
    results of tagging Gulf sturgeon in the Apalachicola River would 
    suggest the fish are genetically or behaviorally imprinted to the 
    chemosensory environment of their home rivers. Stabile et al. (1996) 
    analyzed Gulf sturgeon populations from eight drainages along the Gulf 
    of Mexico for genetic diversity. He noted significant differences among 
    Gulf sturgeon stocks and suggested that they displayed region-specific 
    affinities and may exhibit river-specific fidelity. Stabile et al. 
    (1996) identified five regional or river-specific stocks (from west to 
    east)--(1) Lake Ponchartrain and Pearl River, (2) Pascagoula River, (3) 
    Escambia and Yellow rivers, (4) Choctawhatchee River, and (5) 
    Apalachicola, Ochlockonee, and Suwannee rivers.
    
    Reproduction
    
        Gulf sturgeon are long-lived, reaching at least 42 years in age 
    (Huff 1975). Age at sexual maturity for females ranges from 8 to 17 
    years, and for males from 7 to 21 years (Huff 1975). Fertilized Gulf 
    sturgeon eggs were collected at 2 upriver locations on the Suwannee 
    River (Marchent and Shutters 1996) and 6 upriver sites on the Pea and 
    Choctawhatchee rivers (Fox 1997). Habitat at the egg collection sites 
    consisted of limestone bluffs and outcroppings, cobble, limestone 
    gravel and sand with water depths ranging from 1.4 to 7.9 m (4.5 to 
    26.0 ft). Water temperatures ranged from 18.3  deg.C to 22.0  deg.C 
    (65.0  deg.F to 71.6  deg.F). Chapman et al. (1993) reported that three 
    mature Gulf sturgeon had 458,080; 274,680; and 475,000 eggs and were 
    estimated to have an average fecundity of 20,652 eggs/kg (9,366 eggs/
    lb).
    
    Population
    
        Population estimates for Gulf sturgeon in the Apalachicola River 
    have been conducted from 1984 to 1993. During that period, estimates of 
    fish exceeding 45.0 cm (17.7 in) in length ranged from 96 to 131 fish 
    with a mean of 115 (F. Parauka, FWS, personal communication; U.S. Fish 
    and Wildlife Service and Gulf States Marine Fisheries Commission 1995). 
    In the Suwannee River, a mark/recapture study implemented from 1986 to 
    1994 estimated a population of 1,504 to 3,066 for Gulf sturgeon 
    weighing between 3.0 and 81.0 kg (6.6 to 178.2 lb) (Carr et al. 1996). 
    Morrow et al. (in press) estimated that the summer population of Gulf 
    sturgeon in the West Middle Pearl River, 459 to 1143 mm (18 to 46 in) 
    in length, ranged from 67 to 124 fish.
    
    Habitat Needs
    
        The Gulf sturgeon requires nearshore (bays and estuaries) and 
    offshore (Gulf of Mexico) feeding areas, and freshwater rivers for 
    spawning and resting habitat. Specific habitat needs of the Gulf 
    sturgeon, in the context of the constituent elements discussed above, 
    include:
        1. Migration corridors which support subspecies' distribution 
    throughout its primary range. Primary range for the Gulf sturgeon in 
    freshwater extends from the Mississippi River to the Suwannee River in 
    Florida (Wooley and Crateau 1985). A migration corridor is a Gulf Coast 
    river drainage within the primary range through which sturgeon pass 
    between marine and estuarine environments to freshwater spawning and 
    resting sites. Records of Gulf sturgeon through sightings, incidental 
    captures, and tagging studies have been made over the last ten years 
    from most major drainages and a number of smaller river systems 
    (Reynolds 1993, U.S. Fish and Wildlife Service and Gulf States Marine 
    Fisheries Commission 1995). Tagging studies in the Apalachicola and 
    Suwannee rivers demonstrated the high probability of recapturing fish 
    in the same river where they were first tagged (Wooley and Crateau 
    1985, Foster and Clugston 1997). A small number of sub-adult fish 
    exhibited inter-river movement; however, the data obtained from capture 
    and recapture studies suggest that Gulf sturgeon have a high degree of 
    river
    
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    fidelity. Stabile et al. (1996) noted significant genetic differences 
    among Gulf sturgeon stocks and suggested that they displayed region-
    specific affinities and may exhibit river-specific fidelity which 
    further defines an essential migratory corridor. The significance of 
    this study to critical habitat is discussed in the section on proposed 
    designation.
        2. Silt-free, consolidated bottom substrate composed of rock, 
    gravel or hard sand. This material can be the predominant benthic 
    substrate in some drainages, while in others it can be more patchily 
    distributed (U.S. Fish and Wildlife Service and Gulf States Marine 
    Fisheries Commission 1995). This feature is often associated with 
    springs, geologic outcroppings, and deep holes. Adult, sub-adult, and 
    juvenile Gulf sturgeon frequent such sites and these areas are thought 
    to be important for spawning and resting (Wooley and Crateau 1985, 
    Odenkirk 1989, Carr et al. 1996, Marchent and Shutters 1996, Foster and 
    Clugston 1997). Telemetry and tagging studies further suggest that 
    individuals return to the same areas of the river inhabited the 
    previous summer (Foster 1993, Carr et al. 1996, Foster and Clugston 
    1997, U.S. Fish and Wildlife Service 1989, 1990, 1991, 1992, 1993).
        3. Adequate water quantity and quality for normal behavior in both 
    fresh and brackish environments. Normal behavior includes, but is not 
    limited to, migration of adult, subadult, and juvenile sturgeon; local 
    movement and feeding by larval and juvenile stages; and reproduction. 
    Natural surface and groundwater discharges influence a river's 
    characteristic fluctuations in volume, depth, and velocity (Torak et 
    al. 1993, Leitman et al. 1993). Migrating sturgeon and planktonic 
    larvae are adapted to conditions in their natal rivers which affect 
    distance traveled and survival. These demographics may be influenced by 
    changes in the water quantity parameters (U.S. Fish and Wildlife 
    Service and Gulf States Marine Fisheries Commission 1995).
        Temperature, sediment load, and chemical constituents are important 
    water quality features. Seasonal changes in water temperature trigger 
    sturgeon migration into and out of rivers (Wooley and Crateau 1985). 
    Cooler waters associated with deep holes, springs and spring runs 
    appear to be important for spawning (Marchant and Shutters 1996, Smith 
    and Clugston 1997) and also as refugia from ambient water temperatures 
    during summer and fall (Carr et al. 1996). Sturgeon access to these 
    springs, spring runs, and deep holes may depend upon the maintenance of 
    stream bed elevation through the natural removal and deposition of 
    sediment (U.S. Army Corps of Engineers 1986). Changes in flow dynamics 
    resulting from surface and groundwater withdrawals for drinking and 
    irrigation (Torak et al. 1993, Leitman et al. 1993), and excessive 
    sedimentation resulting from riverbed elevation changes due to dams and 
    other navigation activities (U.S. Army Corps of Engineers 1986) have 
    impacted these sites.
        Undesirable chemicals contaminating river water may enter sturgeon 
    through contact with water, sediment, or food sources. Bateman and Brim 
    (1994, 1995) found heavy metals, other inorganics, organochlorine 
    compounds, and polycyclic aromatic hydrocarbons in juvenile and adult 
    Gulf sturgeon from Florida. A variety of toxic effects to fish from 
    these contaminants have been demonstrated (Mayer and Mehrle 1977, 
    Armstrong 1979, Johnson and Finley 1980, White et al. 1983, Fox 1992).
    
    Historical and Current Threats to the Species
    
        Identified threats for the Gulf sturgeon include historic 
    overexploitation, incidental take, habitat loss and degradation, 
    contaminants, and potential hybridization with a non-native species, 
    the white sturgeon (Acipenser transmontanus), used in aquaculture.
        The Gulf sturgeon historically was considered important because its 
    eggs and smoked flesh were valued foods, its oil was used in paints, 
    and the swim bladder yielded isinglass, a gelatin used in food products 
    and glues (Smith and Clugston 1994). The resulting demand produced an 
    intense and directed fishing industry. Available landing records 
    indicate that the principal commercial, recreational, and subsistence 
    fisheries were in west Florida, especially in the Apalachicola and 
    Suwannee rivers (Burgess 1963, Huff 1975, Swift et al. 1977, Futch 
    1984, Barkuloo 1988). Directed commercial harvest of Gulf sturgeon in 
    other Gulf states was minor or incidental. Most commercial fishing 
    occurred from the late 19th century until the 1970's, with peak catches 
    in Florida recorded around 1900. Harvest thereafter declined swiftly 
    and averaged around three percent of peak until the fishery collapsed 
    by the late 1970's. From 1972 to 1990, State regulatory agencies in 
    Alabama, Mississippi, Florida, and Louisiana enacted laws prohibiting 
    any take of Gulf sturgeon within their jurisdictional waters.
        The historic decline of Gulf sturgeon populations (Barkuloo 1988) 
    begun by over-exploitation was later exacerbated by habitat 
    destruction, degradation, and inaccessibility. Water control 
    structures, high- and low-head dams, and sills within a number of river 
    drainages throughout its range prevent or severely restrict sturgeon 
    access to historic migration routes and spawning areas (Boschung 1976, 
    Murawski and Pacheco 1977, Wooley and Crateau 1985, McDowell 1988). 
    Dredging, spoil disposal, and other navigation maintenance may have 
    adversely affected Gulf sturgeon habitats through lowering of river 
    elevations, elimination of deep holes, and altering of rock substrates 
    (Carr 1983, Wooley and Crateau 1985). Cool waters emanating from 
    springs are believed to be important thermal refugia for sturgeon and 
    other anadromous fish during warm weather (see below).
        S. Carr (pers. comm.) believed that cool water habitats which 
    appear to serve as thermal refugia during summer months may be impacted 
    by reduction in groundwater flows. Leitman et al. (1993) indicated that 
    the major spring-fed flow component of Georgia's Flint River, a major 
    flow contributor to the Apalachicola River during low-flow periods, has 
    been reduced since the early 1970's from groundwater and surface water 
    irrigation withdrawals. More specifically, increased groundwater 
    withdrawal for irrigation in southwest Georgia may result in a 30 
    percent reduction of discharge to streams (Hayes et al. 1983). These 
    actions, in conjunction with drought, may have caused the observed 
    reduction and cessation of water flow from several springs and spring 
    runs in the upper Apalachicola River. Reduction of cool water flows or 
    their complete loss during critical summer periods could subject 
    sturgeon to increased environmental stress.
        Agricultural and industrial contaminants also may be affecting fish 
    populations. DDT and its DDD/DDE metabolites were detected in Gulf 
    sturgeon samples collected from Florida Gulf river drainages between 
    1985 to 1991 (Bateman and Brim 1994). A second organochlorine 
    insecticide, toxaphene, was detected in fish from the Apalachicola 
    River during the same study. General organochlorine effects on fish 
    include reproductive failure, reduced survival of young, and 
    physiological alterations affecting their ability to withstand stress 
    (White et al. 1983). DDT compounds are also known to be endocrine 
    disrupters (Fox 1992). Toxaphene has been shown to impair reproduction, 
    reduce growth in adults and juveniles, and alter collagen formation in 
    fry, resulting in ``broken back syndrome'' (Mayer and Mehrle
    
    [[Page 9972]]
    
    1977). Bateman and Brim (1994, 1995) also detected heavy metals 
    including arsenic, cadmium, lead, mercury, and polycyclic aromatic 
    hydrocarbons, the latter at levels which could adversely affect 
    development and survival of eggs and larval and juvenile fish.
        Accidental or intentional introductions of cultured stocks and non-
    endemic species, such as the white sturgeon (Acipenser transmontanus), 
    could also potentially harm wild Gulf sturgeon stocks. In addition to 
    these anthropogenic impacts, the life history of Gulf sturgeon 
    complicates recovery efforts. Breeding populations take years to 
    establish due to their advanced age at sexual maturity. The subspecies 
    appears to be a home stream spawner, with little if any natural 
    repopulation by migrants from other rivers.
    
    Application of Critical Habitat Designation to Threats
    
        Take of Gulf sturgeon is prohibited throughout its range by section 
    9 of the Act and by State laws. Critical habitat designation would 
    provide no benefit to the application of these prohibitions.
        Habitat loss and degradation and contaminant threats are directly 
    related to physical and biological features essential to the 
    conservation of the Gulf sturgeon. Additional protection from critical 
    habitat designation would apply in the case of Federal actions that 
    were likely to destroy or adversely modify critical habitat yet not 
    jeopardize the continued existence of the species. The Services believe 
    this scenario is highly unlikely. The U.S. Army Corps of Engineers' 
    navigation maintenance activities, dam and water control construction 
    and operations, and permitting program have the potential to affect all 
    of the constituent elements discussed above--(1) migration corridors 
    could be affected by dams and possibly reduced water flow, (2) bottom 
    substrate could be affected by dredging or deposition of dredged 
    materials, and (3) water quality could be affected by increased 
    turbidity or changed temperature, and water quantity could be reduced. 
    In order to trigger an adverse modification biological opinion without 
    jeopardy, such effects would have to appreciably reduce the value of 
    designated critical habitat for both the survival and recovery of the 
    Gulf sturgeon without reducing its reproduction, distribution, or 
    numbers. Most of the Corps' activities will take place in occupied 
    habitat and a significant reduction in habitat value within occupied 
    habitat of the Gulf sturgeon will inevitably reduce its reproduction, 
    distribution, or numbers, thus providing the protection of the jeopardy 
    prohibition. Unoccupied upstream habitat will still be subject to 
    consultation, regardless of critical habitat designation, if a proposed 
    project would affect downstream occupied habitat (e.g., changed water 
    flows). An example would be the Flint and Chattahoochee rivers in 
    Georgia, where the disappearance of Gulf sturgeon occurred following 
    the construction of Jim Woodruff Dam and its locks in Florida in 1956.
        On July 25, 1996, the FWS provided the Corps with a biological 
    opinion on the proposed West Pearl River Navigation Project in 
    Louisiana and Mississippi. The project involved dredging three river 
    segments. The Gulf sturgeon was one of the federally listed species 
    considered in the opinion. Regardless of the lack of designated 
    critical habitat, the FWS considered features of the Gulf sturgeon's 
    habitat (resuspension of sediments, spread of contaminants, turbidity 
    increases from increased navigation, geomorphic changes) in reaching 
    the decision that the project was not likely to jeopardize the 
    continued existence of the Gulf sturgeon. The no jeopardy finding was 
    based on two factors--(1) existing stable populations of the Gulf 
    sturgeon are found in off-project portions of the Lower Pearl River 
    Basin; and (2) The proposed project activities were localized and 
    temporary in nature.
        This biological opinion demonstrates that habitat features are an 
    essential part of the analysis for any biological opinion under the 
    jeopardy standard; that is, any analysis of the effects on 
    reproduction, distribution, or numbers of the Gulf sturgeon would have 
    to consider the effects of changes to the fish's habitat. Critical 
    habitat designation would not have added additional protection--it 
    would not have been possible to arrive at a destruction of adverse 
    modification biological opinion because habitat value for both survival 
    and recovery of the species was not appreciably reduced.
        Permitting under the Environmental Protection Agency's (EPA) 
    National Pollution Discharge Elimination System (NPDES), water quality 
    standards, and pesticide registration have the potential to affect 
    water quality for the Gulf sturgeon. Since the Gulf sturgeon inhabits 
    larger channel areas, the effects of any point discharge into its 
    habitat would likely be minimized by dilution, and the States of 
    Louisiana, Mississippi, Alabama, and Florida set water quality 
    standards that are believed to be protective of aquatic life. The 
    Service believes that if current Federal water quality standards under 
    the CWA are maintained, there will be no need to modify the State's 
    water quality standards to protect habitat for the Gulf sturgeon. 
    Pesticide registration would have to be evaluated on a case-by-case 
    basis. The Services believe that, for these activities to reach the 
    survival and recovery criteria, reproduction, distribution, or numbers 
    of the Gulf sturgeon would be affected and that potential threats can 
    be effectively addressed under the jeopardy standard.
    
    Relation of Critical Habitat Designation to Recovery/Management 
    Plan
    
        Section 4(f)(1) of the Act requires the Services to develop and 
    implement recovery plans for endangered and threatened species, unless 
    such a plan would not promote the conservation of the species.
        The Services classify recovery tasks according to three priorities:
        (1) Priority 1 tasks are actions that must be taken to prevent 
    extinction or to prevent the species from declining irreversibly in the 
    foreseeable future.
        (2) Priority 2 tasks are actions that must be taken to prevent a 
    significant decline in species population, habitat quality, or some 
    other significant negative impact short of extinction.
        (3) Priority 3 tasks are all other actions necessary to meet the 
    recovery objectives.
        The section 7 consultation process is closely linked with recovery 
    through both section 7(a)(1) and 7(a)(2). Because priority 1 and 2 
    tasks are closely related to a species' survival and recovery, they 
    provide guidance on Federal activities that could result in jeopardy or 
    destruction or adverse modification biological opinions. Priority 3 
    tasks provide guidance on activities that could further the 
    conservation of the species, and which would be included by the 
    Services as conservation recommendations, pursuant to 50 CFR 402.14(j) 
    in biological opinions.
        The Recovery/Management Plan (Plan) for the Gulf sturgeon (U.S. 
    Fish and Wildlife Service and Gulf States Marine Fisheries Commission, 
    1995) was written by a recovery/management team including 
    representatives from the affected States, the Services, the U.S. Army 
    Corps of Engineers, the Caribbean Conservation Corporation, the 
    University of Florida, and a commercial fisherman. The Plan was 
    approved by the Services and the Gulf States Marine Fisheries 
    Commission in September 1995. The basic objectives of the Plan are:
        (1) In the short term, prevent further reductions of wild Gulf 
    sturgeon populations throughout the range.
        (2) For recovery, establish population levels that would allow 
    delisting of the
    
    [[Page 9973]]
    
    Gulf sturgeon by management units based on river drainages.
        (3) Establish, following delisting, a self-sustaining population 
    that could support fishing pressure within management units.
        When a recovery plan has been prepared for a species it 
    incorporates the management actions necessary for the conservation of 
    the species. If the recovery tasks involve Federal actions, they are 
    subject to consultation under section 7 of the Act, either between the 
    implementing agency and the Services or, if carried out by FWS or NMFS, 
    within the agency.
        Critical habitat designation is not included as a task in the Plan. 
    However, since potential benefits of critical habitat designation are 
    linked to recovery tasks through the section 7 consultation process, 
    the Services have analyzed priority 1 and 2 recovery actions (those 
    which are required for the survival of the Gulf sturgeon) for potential 
    added protection if critical habitat were designated. The analysis is 
    based on the assumption that loss of habitat value to the point of 
    affecting survival in occupied habitat will, by definition, reduce 
    reproduction, distribution, or numbers of the Gulf sturgeon. Critical 
    habitat designation, therefore, will not add protection in occupied 
    habitat because the definition of destruction or adverse modification 
    and that of jeopardy both require an effect on survival (and recovery) 
    of the species. The high priority tasks are summarized as follows:
    
    ----------------------------------------------------------------------------------------------------------------
                                                              Habitat value affected, not                           
            Priority                      Task                 reproduction, numbers, or         Net benefit from   
                                                                     distribution               critical habitat?   
    ----------------------------------------------------------------------------------------------------------------
    1.......................  1.3.1  Develop and           No                                No.                    
                               implement monitoring                                                                 
                               techniques.                                                                          
    1.......................  2.5.3  Regulate accidental   No                                No.                    
                               and intentional                                                                      
                               introductions.                                                                       
    1.......................  2.1.2  Reduce or eliminate   No                                No.                    
                               incidental mortality.                                                                
    1.......................  2.4.5  Restore natural       No                                No.                    
                               river habitats.                                                                      
    1.......................  2.3.1  Protect habitat with  Potentially                       No.                    
                               existing laws or                                                                     
                               additional laws or                                                                   
                               incentives.                                                                          
    2.......................  2.1.1  Effectively enforce   No                                No.                    
                               take prohibitions.                                                                   
    2.......................  1.1.1  Locate important      No                                No.                    
                               habitats.                                                                            
    2.......................  1.1.2  Characterize          No                                No.                    
                               essential habitat areas.                                                             
    2.......................  1.2  Conduct life history    No                                No.                    
                               studies.                                                                             
    2.......................  2.2.1  Identify              No                                No.                    
                               contaminants.                                                                        
    2.......................  2.2.2  Eliminate             Potentially                       No.                    
                               contaminants.                                                                        
    2.......................  2.4.6  Coordinate            No                                No.                    
                               consistent water projects.                                                           
    2.......................  2.4.1  Identify dam/lock     Yes                               No.                    
                               sites for restoration.                                                               
    2.......................  2.4.4  Minimize effects of   Potentially                       No.                    
                               navigation projects.                                                                 
    2.......................  4.3  Implement projects to   No                                No.                    
                               achieve recovery plan                                                                
                               objectives.                                                                          
    2.......................  4.2  Seek funding for        No                                No.                    
                               recovery activities.                                                                 
    2.......................  2.2.4  Eliminate impacts to  Potentially                       No.                    
                               water quality and quantity.                                                          
    2.......................  2.2.5  Assess effects of     No                                No.                    
                               groundwater pumping on                                                               
                               riverine habitat.                                                                    
    ----------------------------------------------------------------------------------------------------------------
    
        Tasks 1.3.1, 2.5.3, 2.1.2, and 2.1.1 are not habitat related and 
    would not benefit from critical habitat designation. Tasks 1.1.1, 
    1.1.2, 1.2, 2.2.1, 2.4.6, 2.4.1, 4.3, 4.2, and 2.2.5 are informational 
    or procedural and are, therefore, also independent of potential 
    critical habitat benefits.
        Tasks 2.4.5 and 2.3.1 address both occupied and unoccupied habitat; 
    however, there is no priority 1 or 2 task in the plan requiring 
    additional authority for protecting unoccupied habitat. Protection of 
    unoccupied habitat is, therefore, essential for full recovery, but not 
    for survival of the Gulf sturgeon.
        Under tasks 2.2.2, 2.2.4 and 2.4.4 navigation and water quality and 
    quantity projects in unoccupied habitat will not affect survival of the 
    Gulf sturgeon unless they indirectly affect its reproduction, 
    distribution, or numbers in occupied areas. The criterion requiring 
    harm to both ``survival and recovery'' is not met by projects affecting 
    only unoccupied habitat.
        Most of the Plan tasks involve activities that affect the 
    reproduction, numbers, and distribution of the Gulf sturgeon, and, 
    therefore, for which critical habitat designation would afford no 
    additional protection. Tasks that would potentially receive additional 
    protection from the section 7 prohibition on destruction or adverse 
    modification of critical habitat are those that involve unoccupied 
    habitat, where habitat might be reduced in value without affecting 
    reproduction, numbers, or distribution of the Gulf sturgeon. However, 
    habitat related tasks in the Plan involving unoccupied habitat do not 
    meet the ``survival and recovery'' criterion in the definition of 
    destruction or adverse modification. In summary, no high priority 
    recovery plan actions (those which are designed to ensure survival of 
    the Gulf sturgeon) have been identified that would benefit from 
    critical habitat designation. Known or anticipated Federal agency 
    actions that would appreciably diminish the value of critical habitat 
    of the Gulf sturgeon (thereby invoking the destruction or adverse 
    modification standard) would also reduce appreciably the likelihood of 
    both the survival and recovery of the species by reducing its 
    reproduction, numbers, or distribution (thus triggering the jeopardy 
    standard). Both definitions require impairment of survival and recovery 
    and are functionally equivalent.
        Based on the above discussion, the Services have determined that 
    the lack of additional conservation benefit from critical habitat 
    designation for this species makes such designation not prudent.
    
    References Cited
    
        A complete list of all references cited herein is available upon 
    request from the Jacksonville Field Office (see ADDRESSES section).
        Authors: The primary authors of this document are Dr. Michael M. 
    Bentzien and Mr. Francis M. Parauka, FWS; and Ms. Colleen Coogan, NMFS 
    (see ADDRESSES section).
    
        Authority: The authority for this action is the Endangered 
    Species Act, as amended (16 U.S.C. 1531 et seq).
    
    
    [[Page 9974]]
    
    
        Dated: February 20, 1998.
    Jamie Rappaport Clark,
    Director, Fish and Wildlife Service.
    
        Dated: February 24, 1998.
    David L. Evans,
    Deputy Assistant Administrator for Fisheries, National Marine Fisheries 
    Service.
    [FR Doc. 98-5193 Filed 2-26-98; 8:45 am]
    BILLING CODE 4310-55-P
    
    
    

Document Information

Published:
02/27/1998
Department:
Fish and Wildlife Service
Entry Type:
Rule
Action:
Notice of decision on critical habitat designation.
Document Number:
98-5193
Dates:
The finding announced in this notice was made on February 24, 1998.
Pages:
9967-9974 (8 pages)
PDF File:
98-5193.pdf
CFR: (2)
50 CFR 17
50 CFR 226