Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for Alabama Sturgeon (Scaphirhynchus suttkusi, 30361-30374 [E8-11461]

Agencies

• Fish and Wildlife Service
• DEPARTMENT OF THE INTERIOR

[Federal Register Volume 73, Number 102 (Tuesday, May 27, 2008)]
[Proposed Rules]
[Pages 30361-30374]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E8-11461]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[FWS-R4-ES-2008-0058; 92210-1117-0000-FY08-B4]
RIN 1018-AV51


Endangered and Threatened Wildlife and Plants; Designation of 
Critical Habitat for Alabama Sturgeon (Scaphirhynchus suttkusi)

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), propose to 
designate critical habitat for the Alabama sturgeon (Scaphirhynchus 
suttkusi) under the Endangered Species Act of 1973, as amended (Act). 
In total, approximately 524 kilometers (326 miles) of river are 
proposed as critical habitat. The proposed critical habitat includes 
portions of the Alabama and Cahaba Rivers in Autauga, Baldwin, Bibb, 
Clarke, Dallas, Lowndes, Monroe, Perry, and Wilcox Counties, in 
Alabama.

DATES: We will accept comments received or postmarked on or before July 
28, 2008. We must receive requests for public hearings, in writing, at 
the address shown in the ADDRESSES section by July 11, 2008.

ADDRESSES: You may submit comments by one of the following methods:
     Federal eRulemaking Portal: https://www.regulations.gov. 
Follow the instructions for submitting comments.
     U.S. mail or hand-delivery: Public Comments Processing, 
Attn: FWS-R4-ES-2008-0058; Division of Policy and Directives 
Management; U.S. Fish and Wildlife Service; 4401 N. Fairfax Drive, 
Suite 222; Arlington, VA 22203.
    We will not accept e-mail or faxes. We will post all comments on 
https://www.regulations.gov. This generally means that we will post any 
personal information you provide us (see the Public Comments section 
below for more information).

FOR FURTHER INFORMATION CONTACT: Jeff Powell, Aquatic Species 
Biologist, U.S. Fish and Wildlife Service, Alabama Ecological Services 
Field Office, 1208-B Main Street, Daphne, AL 36526; telephone 251/441-
5858; facsimile 251/441-6222. If you use a telecommunications device 
for the deaf (TDD), call the Federal Information Relay Service (FIRS) 
at 800-877-8339.

SUPPLEMENTARY INFORMATION:

Public Comments

    We intend any final action resulting from this proposal to be as 
accurate and effective as possible. Therefore, we request comments or 
suggestions on this proposed rule. We particularly seek comments 
concerning:
    (1) The reasons why we should or should not designate habitat as 
``critical habitat'' under section 4 of the Act (16 U.S.C. 1531 et 
seq.), including whether the benefit of designation would outweigh 
threats to the species caused by the designation, such that the 
designation of critical habitat is not prudent;
    (2) Specific information on:
     The amount and distribution of Alabama sturgeon habitat, 
flows needed by the species; and amount and distribution of free-
flowing waters within the species' historical or present range,
     What areas occupied at the time of listing that contain 
features essential to the conservation of the species we should include 
in the designation and why, and
     What areas not occupied at the time of listing are 
essential for the conservation of the species and why;
    (3) Land-use designations and current or planned activities in the 
subject areas and their possible impacts on proposed critical habitat;
    (4) Information regarding the potential impacts of this proposed 
designation on the activities we have identified that may adversely 
affect critical habitat (see the Application of the ``Adverse 
Modification'' Standard section), specifically those that are 
associated with the following actions:
     Actions that would significantly alter the existing flow 
regime to the point at which the habitat could no longer sustain normal 
behavior and promote species recovery,
     Actions that would significantly alter the morphology and 
stability of the river channel,
     Actions that would significantly decrease the amount of 
currently available free-flowing habitat, and
     Actions that would significantly alter water chemistry 
beyond what is required in the State of Alabama water quality 
standards;
    (5) Any foreseeable economic, national-security, or other potential 
impacts resulting from the proposed designation, and, in particular, 
any impacts on small entities, and the benefits of including or 
excluding areas that exhibit these impacts; and
    (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.
    You may submit your comments and materials concerning this proposed 
rule by one of the methods listed in the ADDRESSES section. We will not 
consider comments sent by e-mail or fax or to an address not listed in 
the ADDRESSES section.
    If you submit a comment via https://www.regulations.gov, your entire 
comment--including any personal identifying information--will be posted 
on the Web site. If you submit a hardcopy comment 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 comments on https://www.regulations.gov.

Background

    In this proposed rule, we intend to discuss only those topics 
directly relevant to the distribution of the Alabama sturgeon and the 
designation of its critical habitat. For more information on the 
species, refer to the final and proposed listing rules published in the 
Federal Register on May 5, 2000 (65 FR 26438), and on March 26, 1999 
(64 FR 14676), respectively.
    Sturgeon is the common name used for large, bony-plated, primitive 
fishes in the family Acipenseridae which typically grow slowly and 
mature late in life. The Alabama sturgeon (Scaphirhynchus suttkusi) is 
the smallest of all the North American sturgeons, typically weighing 
only 1 to 2 kilograms (2 to 4 pounds) at maturity. The head is broad 
and flattened shovel-like at the snout, with a tubular and protrusive 
mouth. As with all sturgeon species, there are four barbels (whisker-
like appendages) located on the bottom of the snout in front of the 
mouth that are used to locate prey. The body is lined with five rows of 
bony plates called scutes. Bony plates also cover the head, back, and 
sides, and the body narrows abruptly to the rear forming a

[[Page 30362]]

narrow stalk between the body and tail. The upper lobe of the tail fin 
is elongated and ends in a long filament. Coloration of the upper body 
is light tan to golden yellow, with a creamy white belly. The life span 
of the Alabama sturgeon is unknown. Although few individuals probably 
exceed 12 to 15 years of age, it is possible the species may live 
longer.
    The Alabama sturgeon is endemic to rivers of the Mobile River Basin 
below the Fall Line (inland boundary of the Coastal Plain) (Mettee et 
al. 1996, p. 83; Boschung and Mayden 2004, p. 109). Its current range 
includes the Alabama River from R.F. Henry Lock and Dam downstream to 
the confluence of the Tombigbee River. The species is also known to 
survive in the Cahaba River. For information on range of the species 
see the Criteria Used to Identify Critical Habitat section of this 
rule.
    Despite extensive and intensive efforts in the decade prior to its 
listing, only eight Alabama sturgeon were captured, or reported 
captured and released. These fish were collected from several locations 
in the Alabama River between Millers Ferry Lock and Dam and its 
confluence with the Tombigbee River (Rider and Hartfield 2007, p. 490). 
Since the 2000 publication of the final rule listing the species, two 
Alabama sturgeon have been captured or reported captured. One of these 
was captured, videotaped, and released in the lower Cahaba River 
shortly after publication of the final rule by a fisherman in July 
2000. The most recent capture was an individual collected from the 
Alabama River below Claiborne Lock and Dam in April 2007, by the 
Alabama Department of Conservation and Natural Resources (ADCNR). This 
fish was implanted with a sonic tag and released in May 2007 at the 
location at which it was captured.
    Flows in the Alabama River are heavily influenced by upstream 
releases from Alabama Power Company and Corps hydropower projects, and 
riverine habitats are fragmented by Claiborne and Millers Ferry Locks 
and Dams. This 240-mile (386-kilometer) stretch of the Alabama River, 
along with the lower Cahaba River, represents the last remaining viable 
habitat for the sturgeon.

Previous Federal Actions

    On May 5, 2000, we listed the Alabama sturgeon as endangered under 
the Act (65 FR 26438). In the final listing rule, we determined that 
designation of critical habitat was prudent but critical habitat was 
not determinable, due to the lack of information on the sturgeon's 
biological and habitat needs.
    Following this listing decision, the Alabama-Tombigbee Rivers 
Coalition (Coalition) brought suit in the United States District Court 
for the Northern District of Alabama under the citizen-suit provision 
of the Act and the judicial review provisions of the Administrative 
Procedure Act, alleging several defects in the listing process. The 
district court dismissed the Coalition's lawsuit for lack of standing, 
but on appeal the U.S. Court of Appeals for the Eleventh Circuit 
reversed, concluding that the Coalition did have standing to challenge 
the listing decision. On remand, the District Court granted the United 
States' motion for summary judgment but ordered the Service to issue 
both a proposed and final rule designating critical habitat by May 14, 
2006, and November 14, 2006, respectively. Alabama-Tombigbee Rivers 
Coalition et al. v. Norton et al., No. CV-01-0194-VEH (Final Order, 
Nov. 14, 2005). The Coalition appealed and the District Court stayed 
the judgment pending review by the Eleventh Circuit. Under the 
direction of the District Court, the Service would have two years from 
the time of the Eleventh Circuit's decision to complete the designation 
of critical habitat.
    On February 8, 2007, the Eleventh Circuit affirmed the decision of 
the District Court, finding among other things that vacating the 
listing decision was not the proper remedy for failure to designate 
critical habitat. Alabama-Tombigbee Rivers Coalition et al. v. 
Kempthorne et al., 477 F.3d 1250 (11th Cir. 2007). On May 16, 2007, the 
Eleventh Circuit issued its judgment as a mandate, thus lifting the 
stay imposed by the District Court and requiring the Service to issue a 
prudency determination and, if prudent, a proposed rule designating 
critical habitat within one year (May 16, 2008), and a final rule 
designating critical habitat within one year after that (May 16, 2009). 
It should be noted that the Coalition asked the Supreme Court to review 
the Eleventh Circuit's decision; that request was denied on January 7, 
2008. Alabama-Tombigbee Rivers Coalition et al. v. Kempthorne et al., 
128 S. Ct. 877 (2008).
    For more information on previous Federal actions concerning Alabama 
sturgeon, refer to the final listing rule, which we published in the 
Federal Register on May 5, 2000 (65 FR 26438). We are proposing this 
action in accordance with section 4(b)(2) of the Act.

Critical Habitat

    Critical habitat is defined in section 3 of the Act as:
    (1) The specific areas within the geographical area occupied by a 
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 a 
species at the time it is listed, upon a determination that such areas 
are essential for the conservation of the species.
    Conservation, as defined under section 3 of the Act, means the use 
of all methods and procedures that are necessary to bring any 
endangered species or threatened species to the point at which the 
measures provided under the Act are no longer necessary.
    Critical habitat receives protection under section 7 of the Act 
through the prohibition against Federal agencies carrying out, funding, 
or authorizing the destruction or adverse modification of critical 
habitat. Section 7 of the Act requires consultation on Federal actions 
that may affect critical habitat. The designation of critical habitat 
does not affect land ownership or establish a refuge, wilderness, 
reserve, preserve, or other conservation area. Such designation does 
not allow the government or public to access private lands. Such 
designation does not require implementation of restoration, recovery, 
or enhancement measures by the landowner. Where the landowner seeks or 
requests federal agency funding or authorization that may affect a 
listed species or critical habitat, the consultation requirements of 
section 7 would apply, but even in the event of a destruction or 
adverse modification finding, the landowner's obligation is not to 
restore or recover the species, but to implement reasonable and prudent 
alternatives to avoid destruction or adverse modification of critical 
habitat.
    For inclusion in a critical habitat designation, habitat within the 
geographical area occupied by the species at the time it was listed 
must contain features that are essential to the conservation of the 
species. Critical habitat designations identify, to the extent known 
using the best scientific data available, habitat areas that provide 
essential life cycle needs of the species (areas on which are found the 
primary constituent elements, as defined at 50 CFR 424.12(b)). Occupied 
habitat that contains the features essential to the conservation of the 
species meets the definition of critical habitat only if those features 
may require special

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management considerations or protection. Under the Act, we can 
designate critical habitat in areas outside the geographical area 
occupied by the species at the time it is listed only when we determine 
that those areas are essential for the conservation of the species.
    Section 4 of the Act requires that we designate critical habitat on 
the basis of the best scientific and commercial data available. 
Further, our Policy on Information Standards Under the Endangered 
Species Act (published in the Federal Register on July 1, 1994 (59 FR 
34271)), the Information Quality Act (section 515 of the Treasury and 
General Government Appropriations Act for Fiscal Year 2001 (Pub. L. 
106-554; H.R. 5658)), and our associated Information Quality 
Guidelines, provide criteria, establish procedures, and provide 
guidance to ensure that our decisions are based on the best scientific 
data available. They require our biologists, to the extent consistent 
with the Act and with the use of the best scientific data available, to 
use primary and original sources of information as the basis for 
recommendations to designate critical habitat.
    When we are determining which areas should be proposed as critical 
habitat, our primary source of information is generally the information 
developed during the listing process for the species. Additional 
information sources may include 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, or other unpublished materials and expert opinion or 
personal knowledge.
    Habitat is often dynamic, and species may move from one area to 
another over time. Furthermore, we recognize that designation of 
critical habitat may not include all of the habitat areas that we may 
eventually determine, based on scientific data not now available to the 
Service, 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 required for 
recovery of the species.
    Areas that support populations, but are outside the critical 
habitat designation, will continue to be subject to conservation 
actions we implement under section 7(a)(1) of the Act. They are also 
subject to the regulatory protections afforded by the section 7(a)(2) 
jeopardy standard, as determined on the basis of the best available 
scientific information at the time of the agency action. Federally 
funded or permitted projects affecting listed species outside their 
designated critical habitat areas may still result in jeopardy findings 
in some cases. Similarly, critical habitat designations made on the 
basis of the best available information at the time of designation will 
not control the direction and substance of future recovery plans, 
habitat conservation plans (HCPs), or other species conservation 
planning efforts if new information available to these planning efforts 
calls for a different outcome.

Methods

    As required by section 4(b) of the Act, we used the best scientific 
data available in determining areas within the geographical area 
occupied at the time of listing that contain features essential to the 
conservation of Alabama sturgeon, and areas outside of the geographical 
area occupied at the time of listing that are essential for the 
conservation of Alabama sturgeon. We have reviewed available 
information pertaining to the habitat requirements of this species. 
This information includes our own published and unpublished data, field 
notes, unpublished survey reports, communications with qualified 
experts, peer-reviewed scientific publications, and the final and 
proposed listing rules for the species. We are not currently proposing 
any areas outside the geographical area presently occupied by the 
species because we are unaware of any suitable areas of habitat for 
this species outside of the area being proposed.
    At the time of listing, we lacked the biological and habitat 
information necessary to identify the primary constituent elements and 
areas essential for conservation. This lack of information continues to 
be an issue, since we have only two confirmed Alabama sturgeon captures 
since publication of the final rule. Therefore, we reviewed the 
available data and information on the Alabama sturgeon's closest 
related species, the pallid (Scaphirhynchus albus) and the shovelnose 
sturgeons (S. platorynchus). Unfortunately, although both the pallid 
and shovelnose sturgeons are more abundant and widely distributed, very 
little specific information is available concerning their biological 
and physical requirements. However, by synthesizing the best scientific 
available data on all three species, and considering historical and 
current conditions at the locations where Alabama sturgeon have been 
collected, we have identified the physical and biological requirements 
of the Alabama sturgeon.

Primary Constituent Elements

    In accordance with section 3(5)(A)(i) of the Act and the 
regulations at 50 CFR 424.12, in determining which areas occupied by 
the species at the time of listing to propose as critical habitat, we 
consider the physical and biological features that are essential to the 
conservation of the species to be the primary constituent elements laid 
out in the appropriate quantity and spatial arrangement for 
conservation of the species. These include, but are not limited to:
    (1) Space for individual and population growth and for normal 
behavior;
    (2) Food, water, air, light, minerals, or other nutritional or 
physiological requirements;
    (3) Cover or shelter;
    (4) Sites for breeding, reproduction, or rearing (or development) 
of offspring; and
    (5) Habitats that are protected from disturbance or are 
representative of the historical, geographical, and ecological 
distributions of a species.
    We derive the specific primary constituent elements (PCEs) required 
for the Alabama sturgeon from its biological needs.

Space for Individual and Population Growth and for Normal Behavior

    All river sturgeons (Scaphirhynchus spp.) are migratory and may 
migrate hundreds of kilometers to spawn. The newly hatched larvae of 
other river sturgeon are free-floating and may drift hundreds of 
kilometers before settling to a benthic juvenile existence. Therefore, 
connectivity of spawning, juvenile, and adult feeding and growing 
habitats is necessary for the conservation of the species.
    Based on collection records, the species is known to inhabit the 
main channel of large coastal plain rivers of the Mobile River Basin. 
Specimens have been taken over a variety of substrates including sand, 
gravel, and mud, from 6 to 14 meters (m) (20 to 46 feet (ft)) deep 
(Williams and Clemmer 1991, p. 26). The U.S. Army Corps of Engineers 
identified 30 locations in the Alabama River where 58 Alabama sturgeon 
were reportedly captured between 1950 and 1998, and documented channel 
morphology and substrate types at 12 of the capture locations during 
low flow conditions. Substrates associated with these capture sites 
included sand, gravel, and limestone outcrops. All capture locations 
downstream of Claiborne Lock and Dam were either on or within 300 m 
(984 ft) of a sandbar.
    Most historical and recent sturgeon capture sites are at or near 
features

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presumably associated with feeding, reproduction, or refugia and 
include rock walls, channel training devices, deep pools, mussel beds, 
and/or stable sand and gravel bottoms (Burke and Ramsey 1985, p. 53, 
Mayden and Kuhajda 1996, p. 257, Hartfield and Garner 1998, p. 4). The 
presence of mussel beds represents stable channel habitats with high 
aquatic invertebrate diversity and density that are likely important 
feeding areas for sturgeon; deeper holes may be used as thermal refugia 
during times of low flow and warmer temperatures (Hartfield and Garner 
1998, p. 5).
    Data collected from a radio-tagged Alabama sturgeon, released in 
1985 near Millers Ferry Lock and Dam on the Alabama River and tracked 
for four months, showed that its preferred position was in swift 
current at a depth of 7.7 to 12.3 m (25 to 40 ft), but never at the 
deepest part at any location except where bottom contour was uniform 
(Burke and Ramsey 1985, p. 32). Irwin et al. (2005, p. 5) and Kynard et 
al. (2007, p. 369) documented that adult shovelnose sturgeon are more 
active at night. This type of behavior was also observed in juvenile 
shovelnose sturgeon (Kynard et al. 2007, p. 369), and a similar pattern 
is currently being observed by the Alabama sturgeon collected in 2007 
that is being tracked in the lower Alabama River (ADCNR and Service 
unpublished data 2007, 2008). During daylight hours in the summer of 
2007, this sturgeon remained in the deeper, flowing portions of the 
channel. However, during the late afternoon and early evening hours, 
the sturgeon moved into shallower habitats directly adjacent to a small 
perennial tributary. We have no evidence that the sturgeon moves into 
these tributaries; it may be taking advantage of cooler water found at 
the interface between the tributaries and the main stem of the river. 
The amount of time this tagged fish spent in these areas suggests these 
areas are important for feeding or for providing a thermal refugia 
during the warmer summer months.

Food

    Reports suggest that the species is an opportunistic bottom feeder 
(Mayden and Kuhajda 1996, p. 257, Williams and Clemmer 1991, p. 26, 
Burke and Ramsey 1985, p. 35). Keevin et al. (2007, p. 500) conducted a 
stomach content analysis on 12 Alabama sturgeon from museum collections 
and found aquatic insects and fish to be the dominate food items. This 
is quite similar to the diets of the pallid and shovelnose sturgeons 
described by Gerrity et al. (2006, p. 606) and Hoover et al. (2007, p. 
494). Except for the absence of fish in the diet of shovelnose 
sturgeon, all three species tended to feed on similar items, primarily 
aquatic insects. The insects identified in these studies are found over 
a variety of substrates including soft and hard rocky bottoms; 
therefore, protection of most shallow-water habitat (shoals, gravel or 
sand bars) is essential to maintaining an acceptable food base. A 
distinct difference observed by Keevin et al. (2007, p. 502) in the 
diet of the Alabama sturgeon was the presence of ceratopogonids (biting 
midges) and siphlonurids (of a family of mayflies). These small, 
aquatic larvae are very active, strong swimmers that tend to occupy the 
water column or areas near the surface (Keevin et al. 2007, p. 502), 
indicating that the sturgeon may be a mid-water column feeder. Irwin et 
al. (2005, p. 39) found that juvenile shovelnose sturgeon 
overwhelmingly preferred feeding in sandy substrates and actively 
avoided gravel areas. It is unknown if this behavior is displayed by 
the Alabama sturgeon, but 2007 tracking data suggest that the species 
may rest in the deeper, fast-flowing areas during the day and feed in 
shallow, sandy shoal areas at night (ADCNR and Service unpublished 
data).

Water Quality

    Egg development and hatching and larval and juvenile development 
require moderate to high levels of dissolved oxygen, as well as 
acceptable levels of other water quality parameters. For example, 
research indicates a high incidence of hermaphrodism in shovelnose and 
pallid sturgeon may be linked to water contamination (U.S. 
Environmental Protection Agency (USEPA) 2007, p. 4).
    There are currently more than 1,600 National Pollutant Discharge 
Elimination System (NPDES) permits issued within the Alabama River 
downstream of the Fall Line, which could impact sturgeon habitat. It is 
possible that some of these point-source discharges, along with other 
non-point sources of pollutants, could produce pollutant concentrations 
that may be harmful to the Alabama sturgeon. At the time of listing in 
May 2000, we believed that State water quality standards (which the 
State adopted from the national standards set by the USEPA) were 
protective of the Alabama sturgeon as long as discharges were within 
permitted limits and enforced according to the provisions of the Clean 
Water Act (Biggins 1994, p. 4). These water quality requirements were 
established with the intent to protect all aquatic resources within the 
State of Alabama and were presumed to be protective of the Alabama 
sturgeon. However, the Service is currently in consultation with the 
USEPA to evaluate the protectiveness of criteria approved in USEPA's 
water quality standards for Alabama sturgeon and other threatened and 
endangered species and their critical habitats as described in the 
Memorandum of Agreement our agencies signed in 2001 (66 FR 11201). 
Other factors that can potentially alter water quality are droughts and 
periods of low flow, non-point source runoff from adjacent land 
surfaces (e.g., excessive amounts of nutrients, pesticides, and 
sediment), and random spills or unregulated discharge events. This 
could be particularly harmful during drought conditions when flows are 
depressed and pollutants are more concentrated. Therefore, adequate 
water quality is essential for normal behavior, growth, and viability 
during all life stages of the sturgeon, including egg development and 
hatching, and larval and juvenile development.

Sites for Breeding, Reproduction, or Rearing (or Development) of 
Offspring

    The Alabama sturgeon is believed to reach sexual maturity between 5 
and 7 years of age. Spawning frequency of both sexes is likely 
influenced by food supply and fish condition, and may occur every 1 to 
3 years. Similar to other river sturgeon, the Alabama sturgeon is 
believed to migrate upstream during the late winter and spring to 
spawn. These movements are likely extensive and cover long distances.
    The capture of 12 individuals (including several gravid females) 
during a single collection trip near the mouth of the Cahaba River on 
March 21, 1969, suggests directional movements during the spawning 
season (Williams and Clemmer 1991, p. 27). Gravid females with ripe 
eggs have also been collected during late March, April, and early May, 
which may indicate a prolonged spring spawning or yearly variations in 
the occurrence of preferred spawning temperatures. Actual timing of 
spawning during this period may also vary depending on water 
temperature and river discharge. All sturgeon species produce eggs that 
are adhesive and require a current for proper development. Although 
specific locations at which eggs have been deposited have not been 
identified for the Alabama sturgeon, they are presumably similar to 
those of other river sturgeons, where eggs are deposited on hard bottom 
substrates such as bedrock, armored gravel, or channel training works 
in deep water

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areas, and possibly in some larger tributaries, such as the Cahaba 
River (Burke and Ramsey 1985, p. 53).
    Although no information about larval development exists for the 
Alabama sturgeon, we assume that the Alabama sturgeon may have similar 
needs as other river sturgeons which require highly oxygenated, long 
stretches of free-flowing water for development. The larvae are 
planktonic, drifting with river currents for 12 to 13 days after 
hatching, and exhibit a swim-up and drift behavior while floating in 
currents (Kynard et al. 2007, p. 365). Research indicates that pallid 
sturgeon larvae can drift more than 200 kilometers (km) (125 miles 
(mi)) during the first 11 days of the larval life stage, depending on 
water velocities, before settling to the benthic environment (Braaten 
and Fuller 2007, p. 1). It is unclear, at present, whether Alabama 
sturgeon require distances comparable to those exhibited by pallid 
sturgeon, but the life history strategy is thought to be the same. A 
further reduction in the distance of free-flowing habitat currently 
available would likely be detrimental to the sturgeon.

Riverine Flows and Channel Stability

    Flows in the Mobile River Basin have been substantially altered 
from natural conditions due to the construction and operation of the 
large number of impoundments. Additionally, the river's temperature, 
biogeochemical processes that would have occurred in the absence of the 
dams, and pollution assimilation capabilities have also been altered. 
Flowing water provides a means for transporting nutrients and food 
items, moderating water temperatures and dissolved oxygen levels, and 
diluting pollutants, as well as transporting and suspending developing 
sturgeon eggs and larvae.
    The quality of water, which comprises the sturgeon's chemical 
habitat, is directly related to the volume of water present in the 
river. It affects sturgeon behavior, growth, and viability in all life 
stages. In 1972, prior to the listing of the sturgeon, a 4,640 cubic-
feet-per-second flow requirement in the Alabama River at Montgomery was 
established. This flow, which is approximately the 7Q10 (a measure of 
lowest 7-day flow measured over a 10-year period) for this section of 
the river, is believed to be protective of the Alabama sturgeon. We 
believe this flow would result in the magnitude, frequency, duration, 
and seasonality of discharge over time that is necessary to maintain 
all life stages of the species in the riverine environment, including 
migration, breeding site selection, resting, larval development, 
protection of cool water refuges during low flow periods, as well as 
sufficient velocities to inhibit excessive sedimentation.
    Aquatic life, including fish, requires acceptable levels of 
dissolved oxygen. The type of organism and its life stage determine the 
level of oxygen required. Generally, among the fish, cold water species 
are the most sensitive, with young life forms being most critical. 
Temperature, another water quality parameter, is related to dissolved 
oxygen. The amount of dissolved oxygen that is present in water (the 
saturation level) depends upon water temperature. As the water 
temperature increases, the saturated dissolved oxygen level decreases. 
The more oxygen there is in the water, the greater the assimilative 
capacity (ability to consume organic wastes with minimal impact) of 
that water (Pitt 2000, pp. 6-7). Biochemical oxygen demand (BOD) is the 
oxygen that would be required to stabilize the waste after its 
discharge into a body of water. Wastewater discharges that have a high 
BOD will have a much greater detrimental effect on stream dissolved 
oxygen during critical summer months than they would during colder 
months. Summer months also have lower stream flow rates, which worsens 
the problem by further reducing the water's assimilative capacity (Pitt 
2000, pp. 6-7). Flows should be sufficient to ensure at least 4 
milligrams per liter of dissolved oxygen during low flow periods based 
on the State water quality standards.
    During 2007 and 2008, the Alabama River Basin experienced the worst 
drought ever recorded. Although this drought is currently recognized as 
the worst drought in modern history, some researchers believe that it 
may not have been that unusual (B. Erhardt, U.S. Army Corps of 
Engineers Meteorologist, pers. comm. 2008). Using bald cypress (a long-
lived species) growth rings as an indication, the 2007-08 hydrologic 
period may have actually been more normal over the last 1000 years than 
conditions experienced over the last 40 years (which may have been 
exceptionally wet). Therefore, considering that sturgeon species have 
survived a range of hydrologic conditions over the years, we believe 
sturgeon are adapted to these periodic low flow conditions. Although 
the sturgeon we are currently tracking survived the 2007-08 drought, we 
do not believe that the Alabama sturgeon is adapted to survive extended 
drought periods where water quality is compromised by excessive 
discharges that the river is unable to assimilate. More specifically, 
as described above, low-flow conditions affect the chemical environment 
occupied by the fish and extended low-flow conditions coupled with 
higher pollutant levels would likely result in behavior changes within 
all life stages, but could be particularly detrimental to early life 
stages (e.g., eggs and larvae).
    Stable river bottoms also are required by the sturgeon. The 
presence of stable river bottoms has been associated with the recent 
and historical captures of sturgeon in the Alabama and Tombigbee 
Rivers. Hartfield and Garner (1998, p. 6) documented the presence of 
stable substrates interspersed between dredge and disposal sites in the 
lower Alabama River. These included areas with stable sand and gravel 
river bottoms, and bedrock walls. The presence of mussel beds and a 
diverse and dense insect community provide an indication that channel 
bottoms are relatively stable (Hartfield and Garner 1998, p. 6). As 
mentioned above, the preferred diet of the sturgeon is aquatic 
invertebrates; therefore, the presence of mussel beds may be an 
important indicator of suitable sturgeon feeding habitat. This is 
consistent with the data that are currently being collected from the 
sturgeon that was released and tracked in 2007. This fish has remained 
in the vicinity of well-known mussel beds on the lower Alabama River 
since its release.

Primary Constituent Elements (PCEs) for the Alabama Sturgeon

    Within the geographical area occupied by the Alabama sturgeon at 
the time of listing, we must identify the PCEs that may require special 
management considerations or protections.
    Based on the above needs and our current knowledge of the life 
history, biology, and ecology of the species, we have determined that 
Alabama sturgeon's PCEs are:
    1. A range of flows with a minimum 7-day flow of 4,640 cubic feet 
per second during normal hydrologic conditions, measured in the Alabama 
River at Montgomery.
    2. River channel with stable sand and gravel river bottoms, and 
bedrock walls, including associated mussel beds.
    3. Limestone outcrops and cut limestone banks, large gravel or 
cobble such as that found around channel training devices, and bedrock 
channel walls that provide riverine spawning sites with substrates 
suitable for egg deposition and development.
    4. Long sections of free-flowing water to allow spawning migrations 
and development of eggs and larvae.
    5. Water temperature not exceeding 90 [deg]Fahrenheit (32 
[deg]Celsius), dissolved

[[Page 30366]]

oxygen content over 4 milligrams per liter, and pH (a measure of 
acidity) within the range of 6.0 to 8.5.
    With this proposed designation of critical habitat, we intend to 
conserve the physical and biological features that are essential to the 
conservation of the species, through the identification of the 
appropriate quantity and spatial arrangement of the PCEs sufficient to 
support the life history functions of the species. The critical habitat 
unit proposed for designation contains all of the PCEs and supports 
multiple life processes.

Special Management Considerations or Protection

    When designating critical habitat, we assess whether the occupied 
areas contain the physical or biological features essential to the 
conservation of the species, and whether these features may require 
special management considerations or protection. It is recognized that 
numerous activities in and adjacent to the unit designated as critical 
habitat, as described in this proposed rule, may affect one or more of 
the PCEs found in that unit. These activities include, but are not 
limited to, those listed in the Application of the ``Adverse 
Modification'' Standard section as activities that may destroy or 
adversely modify critical habitat. We summarize here the primary 
threats to the physical and biological features essential to the 
conservation of the species.
    Water quality, as discussed in the Application of the ``Adverse 
Modification'' Standard section, can influence all life stages of the 
sturgeon. Water pollution and changes in water quality can originate 
from either non-point or point source discharges. Non-point source 
pollution is ubiquitous in the Mobile Basin and can originate from a 
variety of land use practices (such as livestock grazing, row crop 
farming, silvicultural, and residential development). The impacts from 
nearly all non-point source pollutant sources can be managed by 
implementing the appropriate best management practices. This may 
include creation and maintenance of riparian buffers, and control of 
soil loss and runoff from adjacent lands. Point source pollution 
typically originates from industrial and municipal discharges, but may 
include any discharge that originates from a single point. Point source 
pollution can be managed by ensuring that NPDES permitted discharges 
are within compliance at all times. This requires proper water quality 
monitoring and record keeping, and ensuring that enough flow is present 
in the river to assimilate the volume of material that is being 
discharged.
    The Service should be consulted with for disturbances to areas 
upstream of those known to support sturgeon, including perennial 
streams that may provide critical thermal refuges to the sturgeon at 
the interface with the main channel, especially during times when river 
flows are experiencing abnormally low levels (i.e., during droughts). 
Therefore, prior to channel-disturbing activities, these areas should 
be identified and precautions should be taken to ensure that the 
integrity of these areas is maintained. Minimizing the effects of 
navigational dredging and channelization (past evidence of which can be 
seen throughout the historical range of the sturgeon) can be 
accomplished by avoiding the removal of consolidated bed material and 
rock walls, and consulting with the Service on the proper disposal 
areas.

Criteria Used To Identify Critical Habitat

    The Alabama sturgeon is extremely rare. Despite extensive and 
intensive efforts in the decade prior to its listing, only eight 
Alabama sturgeon were captured, or reported captured and released. All 
river sturgeons are migratory and may migrate hundreds of kilometers to 
spawn, and newly hatched larvae may drift hundreds of kilometers before 
settling. Therefore, connectivity of spawning, juvenile, and adult 
feeding and developmental habitats is necessary for the conservation of 
the species.
    We began our analysis by evaluating the Alabama sturgeon in the 
context of its distribution throughout the historical range to 
determine what portion of the range must be included to ensure 
conservation of the species. We considered several factors in this 
evaluation: (1) Inclusion of reaches that provide the highest 
likelihood of egg and juvenile development, (2) inclusion of reaches 
that contain suitable spawning habitat, and (3) inclusion of areas that 
provide protection of the species during low flow periods and other 
catastrophic events.
    The historical range of the Alabama sturgeon included nearly every 
major basin in the Mobile River basin downstream of the Fall Line, 
comprising nearly 1,600 km (1,000 mi) of riverine habitat in the Mobile 
River Basin in Alabama and Mississippi. There are records of Alabama 
sturgeon from nearly all the major rivers in the Mobile River Basin 
below the Fall Line, including the Black Warrior, Tombigbee, Alabama, 
Coosa, Tallapoosa, Mobile, Tensaw, and Cahaba Rivers (Burke and Ramsey 
1985, p. 1). However, over the last century, the species has 
disappeared from at least 85 percent of its historical range, and since 
the 1960s has experienced a significant decline in the remaining range.
    Recent collections (since 1990) of the Alabama sturgeon are 
confined to the lower Alabama River from its confluence with the 
Tombigbee River upstream to R.F. Henry Lock and Dam, including the 
lower Cahaba River (Rider and Hartfield 2007, p. 492). The entire 
historical range of the Alabama sturgeon is now controlled by a series 
of more than 25 large locks or dams. These man-made structures have 
resulted in a series of impoundments that are interspersed with free-
flowing reaches of varying lengths. Within the Alabama sturgeon's 
historical range there are three dams on the Alabama River (completed 
between 1969 and 1971), two on the Black Warrior River (completed by 
1971), and six on the Tombigbee River (completed between 1955 and 
1985). These 11 dams alone have impounded and fragmented more than 970 
km (583 mi) of riverine habitat once occupied by sturgeon. Prior to 
construction of these structures, sturgeon could move freely between 
feeding areas, and from feeding areas to sites that were suitable for 
spawning and development of eggs and larvae.
    The locks and dams that impound the river constitute barriers to 
sturgeon passage. Although fish species that occupy the middle of the 
water column (e.g., shad, catfishes, paddlefish) could, and do, pass 
through the locks while they are being operated, there is no evidence 
to suggest that sturgeon pass through the lock chambers during normal 
lockages. Most adult sturgeons, including the Alabama sturgeon, are 
benthic (bottom-dwelling) cruisers, and are not likely to move up in 
the water column to scale physical hurdles (Cooke et al. 2002, p. 108). 
The lock chambers at Millers Ferry and Claiborne Locks and Dams have 
upper and lower sills which form a rather large hurdle (about 30 feet 
above the river floor at the upper end of Miller Ferry) for sturgeon 
moving upstream and downstream.
    With migration routes impeded, isolated subpopulations of Alabama 
sturgeon are unable to successfully recruit adequate numbers to 
replenish the population. Reduced numbers of recruited sturgeon and 
surviving adult fish can become more vulnerable to localized declines 
in water and habitat quality caused by hydropower releases, local 
riverine and land management practices, or by polluted discharges. It 
is unlikely that Alabama sturgeon habitat and life cycle requirements 
can be met in long stretches of low flow, such as those that exist in 
the impounded areas

[[Page 30367]]

of the river, where decreased flows typically cause silt and other fine 
sediments to accumulate over bottom habitats, creating unsuitable 
conditions for spawning, feeding, and larval growth and development.
    The Alabama sturgeon is considered extirpated from the upper 
Alabama, Black Warrior, Tombigbee, Coosa, Tallapoosa, Mobile, and 
Tensaw Rivers. The Upper Alabama is isolated by Robert F. Henry Lock 
and Dam, and this reach of the river is essentially impounded to the 
confluence of the Coosa and Tallapoosa Rivers, and does not contain 
appropriate habitat for the conservation of the Alabama sturgeon.
    Sturgeon have not been collected from the Black Warrior, Coosa, 
Tallapoosa or Tombigbee Rivers in more than 30 years. With the 
exception of the extreme lower Tombigbee River, all of these areas are 
isolated from currently occupied river reaches and their riverine 
habitats are impounded and highly fragmented by multiple large river 
dams. Although some isolated areas within these drainages may contain 
some of the appropriate habitat features for Alabama sturgeon, their 
limited extent and the lack of continuity or accessibility to other 
habitats limits their value to the species.
    The Mobile, Tensaw, and lower Tombigbee Rivers are currently 
accessible to Alabama sturgeon; however, there have been no confirmed 
collections of the species in more than 20 years. In addition, the 
natural hydrograph of the lower Mobile Basin has been radically altered 
by multiple navigation and hydropower dams on the Tombigbee River, and 
the flows are seasonally highly variable. These areas may be 
occasionally used or visited by subadult or adult Alabama sturgeon; 
however, there is no recent evidence that this is occurring and little 
historical evidence of such use. Although some habitat features occur 
in these river reaches, their value in conservation of the species is 
not known.
    At the time of listing, we considered the Alabama River from south 
of Miller's Ferry Lock and Dam to the confluence of the Tombigbee River 
to be occupied. Shortly after publication of the listing rule, an 
Alabama sturgeon was captured and released at river mile 8.5 in the 
Cahaba River. This capture of an adult sturgeon indicated that this 
area also was occupied at the time of listing, given that the fish 
could not have reached this area from other sections of the river due 
to the lock and dam arrangement (see the Riverine Flows and Channel 
Stability section), and would have been present at the time the rule 
was published in the Federal Register. Given the fish's proximity to 
the mouth of the Cahaba River and the lack of barriers with the Alabama 
River section located between R.F. Henry Lock and Dam and the Millers 
Ferry Lock and Dam, we believe the fish likely to use all of these 
areas, and, therefore, consider them occupied at the time of listing. 
There is some evidence of past upstream spawning runs in the Cahaba 
River as well (Williams and Clemmer 1991, p. 27). Based on historical 
information and recent collections, we consider all of the following 
areas to be currently occupied: The Alabama River from R.F. Henry Lock 
and Dam downstream to the confluence of the Tombigbee River, and the 
Cahaba River from its confluence with the Alabama River upstream to 
U.S. Highway 82 which is close to the Fall Line at Centreville, 
Alabama. Given the lack of appropriate habitat elsewhere within the 
historical range, we conclude that this proposed designation should 
include all currently occupied habitat.
    Once we determined that the proper scale of the proposed critical 
habitat designation should cover the area currently occupied by the 
species, we assessed the critical life history components of Alabama 
sturgeon as they relate to habitat. Alabama sturgeon use the rivers for 
spawning, larval and juvenile feeding and development, adult resting, 
feeding, and staging, and to move between the areas that support these 
components. Therefore, all areas meeting these requirements were 
considered for inclusion.
    We then investigated the habitat types that support these life 
history components and where these habitat areas are located. We 
evaluated empirical data (including that gathered from recent 
radiotelemetry), recent channel bathymetry data (collected by the U.S. 
Army Corps of Engineers), as well as published and unpublished 
literature. These habitat components are described in the Primary 
Constituent Elements section of this proposed rule.
    To determine which areas should be designated as critical habitat, 
we then evaluated where the necessary physical and biological features 
of Alabama sturgeon habitat occur within the currently occupied 
habitat. Detailed location data are included in the unit description in 
the Proposed Critical Habitat Designation section of this proposed 
rule. We have determined that these areas occur from the Alabama River, 
at its confluence with the Tombigbee River, upstream to R.F. Henry Lock 
and Dam. This also includes the Cahaba River upstream to U.S. Highway 
82 near the Fall Line in Bibb County. All of these areas support one or 
more of the PCEs and are accessible to sturgeon (i.e., not entirely 
blocked by dams). All life stages are associated with flowing waters 
and other features characteristic of free-flowing riverine habitats. 
Nearly the entire length of the Alabama and Cahaba River currently meet 
these requirements. This area is being proposed as critical habitat to 
ensure adequate protection of spawning sites, habitat needed for 
juvenile development, and movement of adult sturgeon to and from 
spawning areas.
    When determining proposed critical habitat boundaries within this 
proposed rule, we made every effort to avoid including developed areas 
such as waterways covered by buildings, docks, dams, and other 
structures because such waterways lack PCEs for Alabama sturgeon. 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 developments. Any such areas 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, a Federal action involving 
these areas would not trigger section 7 consultation with respect to 
critical habitat and the requirement of no adverse modification unless 
the specific action may affect adjacent critical habitat.

Proposed Critical Habitat Designation

    We are proposing to designate one contiguous section of the Alabama 
River and a portion of the lower Cahaba River as one critical habitat 
unit for Alabama sturgeon. The areas we describe below constitute our 
current best assessment of areas that meet the definition of critical 
habitat for the Alabama sturgeon. The single unit we propose as 
critical habitat is the Alabama River from its confluence with the 
Tombigbee River, Clarke and Baldwin Counties, Alabama, upstream to R.F. 
Henry Lock and Dam, Autauga and Lowndes Counties, Alabama; and the 
Cahaba River from its confluence with the Alabama River upstream to 
U.S. Highway 82 near the Fall Line in Bibb County, Alabama.
    Following review of all areas within the range of the species, we 
have determined that the proposed critical habitat area meets the 
definition of critical habitat.
    Table 1 shows the occupied unit, land ownership and approximate 
area.

[[Page 30368]]



        Table 1.--Occupancy of Alabama Sturgeon and Land Ownership of the Proposed Critical Habitat Unit
----------------------------------------------------------------------------------------------------------------
                                                                            Size of unit
      Critical habitat unit       Occupied at time of       Currently       in kilometers    Land ownership by
                                        listing             occupied           (miles)              type
----------------------------------------------------------------------------------------------------------------
Alabama and Cahaba Rivers.......  yes................  yes...............       524 (326)  State.
----------------------------------------------------------------------------------------------------------------

    Below, we present a brief description of the unit and reasons why 
it meets the definition of critical habitat for the Alabama sturgeon.

Unit: Alabama and Cahaba Rivers, Alabama

    The critical habitat unit encompasses 524 km (326 mi) of river 
channel. The portion of river channel in the Alabama River extends 394 
km (245 mi) from its confluence with the Tombigbee River, Baldwin and 
Clarke Counties, Alabama, upstream to R.F. Henry Lock and Dam, Autauga 
and Lowndes Counties, Alabama; and the portion of river channel in the 
Cahaba River extends 130 km (81 mi) from its confluence with the 
Alabama River, Dallas County, Alabama, upstream to U.S. Highway 82, 
Bibb County, Alabama. The Alabama and Cahaba Rivers are the last known 
areas that still support the sturgeon, both of which were occupied at 
the time of listing. This was recently confirmed by the 2007 collection 
of an individual from the Alabama River below Claiborne Lock and Dam, 
and the 2000 collection of an individual from the lower Cahaba River 
(ADCNR pers. comm. 2007). Although the Alabama River, within this unit, 
contains two physical barriers (Claiborne and Millers Ferry Locks and 
Dams), it supports the PCEs to sustain this extremely rare fish. The 
single critical habitat unit includes the channel of the rivers and 
streams listed between the ordinary high water mark on each bank, which 
is defined in 33 CFR 329.11 as ``the line on the shore established by 
the fluctuations of water and indicated by physical characteristics 
such as clear, natural line impressed on the bank; shelving; changes in 
the character of the soil; destruction of terrestrial vegetation; the 
presence of litter and debris; or other appropriate means that consider 
the characteristics of the surrounding areas.'' The distances between 
landmarks marking the upstream and downstream boundaries of the unit 
are given in kilometers and equivalent miles, as measured by tracing 
the thalweg (a line connecting the lowest points of successive cross 
sections) of the stream, not the straight-line distance. River miles 
referenced in this rule were taken from a Corps of Engineers 1985 
stream mileage table.
    The river channel within the entire unit is owned by the State of 
Alabama, and the vast majority of adjacent lands are under private 
ownership, with the exception of a portion of the Cahaba River that 
includes Talladega National Forest (Oakmulgee Division). Although the 
Oakmulgee Division encompasses a total of 63,483.7 hectares (ha) 
(156,871 acres (ac)), there are only about 9,951.6 ha (24,591 ac) that 
are directly adjacent to the Cahaba River. The Barton Beach Reserve, a 
small tract owned by The Nature Conservancy, encompasses 45.3 ha (112 
ac) and covers approximately 1,150 meters (m) (3,773 ft) along the 
Cahaba River. This unit meets the definition of critical habitat based 
on the discussion above and contains all PCEs. This unit was known to 
be occupied at the time of listing and is currently occupied. Special 
management of the PCEs for the Alabama sturgeon and its habitat may be 
required for the following threats: low flow conditions, detrimental 
changes in water quality, reduction in the amount of free-flowing 
habitat, and detrimental changes to the morphology or stability of the 
river channel.

Effects of Critical Habitat Designation

Section 7 Consultation

    Section 7(a)(2) of the Act requires Federal agencies, including the 
Service, to ensure that actions they fund, authorize, or carry out are 
not likely to jeopardize the continued existence of a listed species or 
destroy or adversely modify designated critical habitat. Decisions by 
the 5th and 9th Circuit Courts of Appeals have invalidated our 
definition of ``destruction or adverse modification'' (50 CFR 402.02) 
(see Gifford Pinchot Task Force v. U.S. Fish and Wildlife Service, 378 
F.3d 1059 (9th Cir 2004) and Sierra Club v. U.S. Fish and Wildlife 
Service et al., 245 F.3d 434, 442F (5th Cir 2001)), and we do not rely 
on this regulatory definition when analyzing whether an action is 
likely to destroy or adversely modify critical habitat. Under the 
statutory provisions of the Act, we determine destruction or adverse 
modification on the basis of whether, with implementation of the 
proposed Federal action, the affected critical habitat would remain 
functional (or retain the current ability for the PCEs to be 
functionally established) to serve its intended conservation role for 
the species.
    Section 7(a)(4) of the Act requires Federal agencies to confer with 
us on any action that is likely to jeopardize the continued existence 
of a proposed species or result in destruction or adverse modification 
of proposed critical habitat. Conference reports provide conservation 
recommendations to assist the agency in eliminating conflicts that may 
be caused by the proposed action. We may issue a formal conference 
report if requested by a Federal agency. Formal conference reports on 
proposed critical habitat contain an opinion that is prepared according 
to 50 CFR 402.14, as if critical habitat were designated. We may adopt 
the formal conference report as the biological opinion when the 
critical habitat is designated, if no substantial new information or 
changes in the action alter the content of the opinion (see 50 CFR 
402.10(d)). The conservation recommendations in a conference report are 
advisory.
    If a species is listed or critical habitat is designated, section 
7(a)(2) of the Act requires Federal agencies to ensure that activities 
they authorize, fund, or carry out are not likely to jeopardize the 
continued existence of the species or to destroy or adversely modify 
its critical habitat. If a Federal action may affect a listed species 
or its critical habitat, the responsible Federal agency (action agency) 
must enter into consultation with us. As a result of this consultation, 
we document compliance with the requirements of section 7(a)(2) through 
our issuance of:
    (1) A concurrence letter for Federal actions that may affect, but 
are not likely to adversely affect, listed species or critical habitat; 
or
    (2) A biological opinion for Federal actions that are likely to 
adversely affect listed species or critical habitat.
    When we issue a biological opinion concluding that a project is 
likely to jeopardize the continued existence of a listed species or 
destroy or adversely modify critical habitat, we also provide 
reasonable and prudent alternatives to the project, if any are 
identifiable. We define ``Reasonable and Prudent Alternatives'' at 50 
CFR 402.02 as

[[Page 30369]]

alternative actions identified during consultation that:
    (1) Can be implemented in a manner consistent with the intended 
purpose of the action,
    (2) Can be implemented consistent with the scope of the Federal 
agency's legal authority and jurisdiction,
    (3) Are economically and technologically feasible, and
    (4) Would, in the Director's opinion, avoid jeopardizing the 
continued existence of the listed species or destroying or adversely 
modifying critical habitat.
    Reasonable and prudent alternatives can vary from slight project 
modifications to extensive redesign or relocation of the project. Costs 
associated with implementing a reasonable and prudent alternative are 
similarly variable.
    When we issue a biological opinion concluding that a project is not 
likely to jeopardize a listed species or adversely modify critical 
habitat, but may result in incidental take of listed animals, we 
provide an incidental take statement that specifies the impact of such 
incidental taking on the species. We then define ``Reasonable and 
Prudent Measures'' considered necessary or appropriate to minimize the 
impact of such taking. Reasonable and prudent measures are binding 
measures the action agency must implement to receive an exemption to 
the prohibition against take contained in section 9 of the Act. These 
reasonable and prudent measures are implemented through specific 
``Terms and Conditions'' that must be followed by the action agency or 
passed along by the action agency as binding conditions to an 
applicant. Reasonable and prudent measures, along with the terms and 
conditions that implement them, cannot alter the basic design, 
location, scope, duration, or timing of the action under consultation 
and may involve only minor changes (50 CFR 402.14). The Service may 
provide the action agency with additional conservation recommendations, 
which are advisory and not intended to carry binding legal force.
    Regulations at 50 CFR 402.16 require Federal agencies to reinitiate 
consultation on previously reviewed actions in instances where we have 
listed a new species or subsequently designated critical habitat that 
may be affected and the Federal agency has retained discretionary 
involvement or control over the action (or the agency's discretionary 
involvement or control is authorized by law). Consequently, Federal 
agencies may sometimes need to request reinitiation of consultation 
with us on actions for which formal consultation has been completed, if 
those actions with discretionary involvement or control may affect 
subsequently listed species or designated critical habitat.
    Federal activities that may affect Alabama sturgeon or its 
designated critical habitat will require section 7(a)(2) consultation 
under the Act. Activities on State, Tribal, local or private lands 
requiring a Federal permit (such as a permit from the U.S. Army Corps 
of Engineers under section 404 of the Clean Water Act (33 U.S.C. 1251 
et seq.) or a permit from us under section 10(a)(1)(B) of the Act) or 
involving some other Federal action (such as funding from the Federal 
Highway Administration, Federal Aviation Administration, or the Federal 
Emergency Management Agency) are examples of agency actions that may be 
subject to the section 7(a)(2) consultation process. Federal actions 
not affecting listed species or critical habitat, and actions on State, 
Tribal, local or private lands that are not federally funded, 
authorized, or permitted, do not require section 7(a)(2) consultations.

Application of the ``Adverse Modification'' Standard

    The key factor related to the adverse modification determination is 
whether, with implementation of the proposed Federal action, the 
affected critical habitat would continue to serve its intended 
conservation role for the species, or would retain its current ability 
for the primary constituent elements to be functionally established. 
Activities that may destroy or adversely modify critical habitat are 
those that alter the physical and biological features to an extent that 
appreciably reduces the conservation value of critical habitat for 
Alabama sturgeon. Generally, the conservation role of Alabama sturgeon 
critical habitat unit is to support the various life-history needs of 
the species.
    Section 4(b)(8) of the Act requires us to briefly evaluate and 
describe, in any proposed or final regulation that designates critical 
habitat, activities involving a Federal action that may destroy or 
adversely modify such habitat, or that may be affected by such 
designation.
    Activities that, when carried out, funded, or authorized by a 
Federal agency, may adversely affect critical habitat and, therefore, 
should result in consultation for Alabama sturgeon include, but are not 
limited to the following (please see Special Management Considerations 
or Protection section for a more detailed discussion on the impacts of 
these actions to the listed species):
    (1) Actions that would significantly alter the existing flow regime 
to the point at which the habitat could no longer sustain normal 
behavior and promote species recovery. Such activities