Endangered and Threatened Species; Critical Habitat for the Endangered Distinct Population Segment of Smalltooth Sawfish, 70290-70308 [E8-27629]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 73, Number 225 (Thursday, November 20, 2008)]
[Proposed Rules]
[Pages 70290-70308]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E8-27629]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Part 226

[Docket No. 070717355-8030-01]
RIN 0648-AV74


Endangered and Threatened Species; Critical Habitat for the 
Endangered Distinct Population Segment of Smalltooth Sawfish

AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and 
Atmospheric Administration (NOAA), Commerce.

ACTION: Proposed rule; request for comments.

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SUMMARY: We, the National Marine Fisheries Service (NMFS), propose to 
designate critical habitat for the U.S. DPS of smalltooth sawfish 
(Pristis pectinata), which was listed as endangered on April 1, 2003, 
under the Endangered Species Act (ESA). The proposed critical habitat 
consists of two units: the Charlotte Harbor Estuary Unit, which 
comprises approximately 221,459 acres of coastal habitat; and the Ten 
Thousand Islands/Everglades Unit (TTI/E), which comprises approximately 
619,013 acres of coastal habitat. The two units are located along the 
southwestern coast of Florida between Charlotte Harbor and Florida Bay.

DATES: Comments on this proposed rule must be received by January 20, 
2009.

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ADDRESSES: You may submit comments, identified by the Regulatory 
Information Number (RIN) 0648-AV74, by any of the following methods:
    Mail: Assistant Regional Administrator, Protected Resources 
Division, NMFS, Southeast Regional Office, 263 13th Avenue South, St. 
Petersburg, FL 33701.
    Facsimile (fax) to: 727-824-5309.
    Electronic Submissions: Submit all electronic comments to 
www.regulations.gov by clicking on ``Search for Dockets'' at the top of 
the screen, then entering the RIN in the ``RIN'' field and clicking the 
``Submit'' tab.
    Instructions: All comments received are considered part of the 
public record and will generally be posted to https://
www.regulations.gov. All Personal Identifying Information (i.e., name, 
address, etc.) voluntarily submitted may be publicly accessible. Do not 
submit Confidential Business Information or otherwise sensitive or 
protected information. NMFS will accept anonymous comments (enter ``n/
a'' in the required fields if you wish to remain anonymous). Please 
provide electronic attachments using Microsoft Word, Excel, 
WordPerfect, or Adobe PDF file formats only.

FOR FURTHER INFORMATION CONTACT: Shelley Norton, NMFS, Southeast 
Regional Office, at 727-824-5312; or Lisa Manning, NMFS, Office of 
Protected Resources, at 301-713-1401.

SUPPLEMENTARY INFORMATION:

Background

    Under the ESA, we are responsible for determining whether certain 
species are threatened or endangered and for designating critical 
habitat for such species (16 U.S.C. 1533). On April 1, 2003, we listed 
the U.S. distinct population segment (DPS) of smalltooth sawfish (``the 
species'') as endangered (68 FR 15674). At the time of listing, we also 
announced that critical habitat was not then determinable because we 
were completing ongoing studies necessary for the identification of 
specific habitats and environmental features important for the 
conservation of the species. Subsequently, we have sponsored additional 
research on the species, its habitat use, and its conservation needs. 
Additionally, NMFS has developed a draft recovery plan for the species 
pursuant to section 4(f) of the ESA. NMFS has now reviewed the best 
available scientific data and identified specific areas on which are 
located those physical and biological features essential to the 
conservation of the species.

Smalltooth Sawfish Natural History

    The following discussion of the distribution, life history, and 
habitat use of the U.S. DPS of smalltooth sawfish is based on the best 
available commercial and scientific information, including information 
provided in the Status Review (65 FR 12959, March 10, 2000) and the 
Draft Smalltooth Sawfish Recovery Plan (71 FR 49418, August 23, 2006).

Distribution and Range

    Smalltooth sawfish are tropical marine and estuarine elasmobranch 
(e.g., sharks, skates, and rays) fish that are reported to have a 
circumtropical distribution. The historic range of the smalltooth 
sawfish in the United States extends from Texas to New York (NMFS, 
2006). The U.S. region that has historically harbored the largest 
number of smalltooth sawfish is south and southwest Florida from 
Charlotte Harbor to the Dry Tortugas. Most capture records along the 
Atlantic coast north of Florida are from spring and summer months and 
warmer water temperatures. Most specimens captured along the Atlantic 
coast north of Florida have also been large (greater than 10 ft or 3 m) 
adults and are thought to represent seasonal migrants, wanderers, or 
colonizers from a core or resident population(s) to the south rather 
than being resident members of a continuous, even-density population 
(Bigelow and Schroeder, 1953). Historic records from Texas to the 
Florida Panhandle suggest a similar spring and summer pattern of 
occurrence. While less common, winter records from the northern Gulf of 
Mexico suggest a resident population, including juveniles, may have 
once existed in this region.
    The Status Review Team (NMFS, 2000) compiled information from all 
known literature accounts, museum collection specimens, and other 
records of the species. The species suffered significant population 
decline and range constriction in the early to mid 1900's. Encounters 
with the species outside of Florida have been rare since that time.
    Since the 1990's, the distribution of smalltooth sawfish in the 
United States has been restricted to peninsular Florida (Seitz and 
Poulakis, 2002; Poulakis and Seitz, 2004; Simpfendorfer and Wiley, 
2005; Mote Marine Laboratory's National Sawfish Encounter Database 
[MMLNSED]). Encounter data indicates smalltooth sawfish encounters can 
be found with some regularity only in south Florida from Charlotte 
Harbor to Florida Bay. A limited number of reported encounters (one in 
Georgia, one in Alabama, one in Louisiana, and one in Texas) have 
occurred outside of Florida since 1998.
    Peninsular Florida is the main U.S. region that historically and 
currently hosts the species year-round because the region provides the 
appropriate climate (subtropical to tropical) and contains the habitat 
types (lagoons, bays, mangroves, and nearshore reefs) suitable for the 
species. Encounter data and research efforts indicate a resident, 
reproducing population of smalltooth sawfish exists only in southwest 
Florida (Simpfendorfer and Wiley, 2005).

Life History

    Smalltooth sawfish are approximately 31 in (80 cm) in total length 
at birth and may grow to a length of 18 ft (540 cm) or greater. A 
recent study by Simpfendorfer et al. (2008) suggests rapid juvenile 
growth occurs during the first two years after birth. First year growth 
is 26-33 in (65-85 cm) and second year growth is 19-27 in (48-68 cm). 
Growth rates beyond two years are uncertain; however, the average 
growth rate of captive smalltooth sawfish has been reported between 5.8 
in (13.9 cm) and 7.7 in (19.6 cm) per year. Apart from captive animals, 
little is known of the species' age parameters (i.e., age-specific 
growth rates, age at maturity, and maximum age). Simpfendorfer (2000) 
estimated age at maturity between 10 and 20 years, and a maximum age of 
30 to 60 years. Unpublished data from Mote Marine Laboratory (MML) and 
NMFS indicates male smalltooth sawfish do not reach maturity until they 
reach 133 in (340 cm).
    No directed research on smalltooth sawfish feeding habits exists. 
Reports of sawfish feeding habits suggest they subsist chiefly on small 
schooling fish, such as mullets and clupeids. They are also reported to 
feed on crustaceans and other bottom-dwelling organisms. Observations 
of sawfish feeding behavior indicate that they attack fish by slashing 
sideways through schools, and often impale the fish on their rostral 
(saw) teeth (Breeder, 1952). The fish are subsequently scraped off the 
teeth by rubbing them on the bottom and then ingested whole. The oral 
teeth of sawfish are ray-like, having flattened cusps that are better 
suited to crushing or gripping.
    Very little is known about the specific reproductive biology of the 
smalltooth sawfish. As with all elasmobranchs, fertilization occurs 
internally. The embryos of smalltooth sawfish, while still bearing the 
large yolk sac, resemble adults relative to the position of their fins 
and absence of the lower caudal lobe. During embryonic development,

[[Page 70292]]

the rostral blade is soft and flexible. The rostral teeth are also 
encapsulated or enclosed in a sheath until birth. Shortly after birth, 
the teeth become exposed and attain their full size, proportionate to 
the size of the saw. Total length of the animal at birth is 
approximately 31 in (80 cm), with the smallest free-living specimens 
reported during field studies in Florida being 27-32 in (69-81 cm) 
(Simpfendorfer et al., 2008). Documentation on the litter size of 
smalltooth sawfish is very limited. Gravid females have been documented 
carrying between 15-20 embryos; however, the source of this data is 
unclear and may represent an over-estimate of litter size. Studies of 
largetooth sawfish in Lake Nicaragua (Thorson, 1976) report brood sizes 
of 1-13 individuals, with a mean of 7.3 individuals. The gestation 
period for largetooth sawfish is approximately 5 months, and females 
likely produce litters every second year. Although there are no such 
studies on smalltooth sawfish, their similarity to the largetooth 
sawfish implies that their reproductive biology may be similar. Genetic 
research currently underway may assist in determining reproductive 
characteristics (i.e., litter size and breeding periodicity).
    No confirmed breeding sites have been identified to date since 
directed research began in 1998. Research is underway to investigate 
areas where adult smalltooth sawfish have been reported to congregate 
along the Everglades coast to determine if breeding is occurring in the 
area.
    Life history information on the smalltooth sawfish has been 
evaluated using a demographic approach and life history data on 
largetooth sawfish and similar species from the literature. 
Simpfendorfer (2000) estimates intrinsic rates of natural population 
increase as 0.08 to 0.13 per year and population doubling times from 
5.4 to 8.5 years. These low intrinsic rates of population increase are 
associated with the life history strategy known as ``k-selection.'' K-
selected animals are usually successful at maintaining relatively 
small, persistent population sizes in relatively constant environments. 
Consequently, they are not able to respond effectively (rapidly) to 
additional and new sources of mortality resulting from changes in their 
environment. Musick (1999) and Musick et al. (2000) noted that 
intrinsic rates of increase less than ten percent were low, and such 
species are particularly vulnerable to excessive mortalities and rapid 
population declines, after which recovery may take decades. Thus, 
smalltooth sawfish populations are expected to recover slowly from 
depletion. Simpfendorfer (2000) concluded that recovery was likely to 
take decades or longer, depending on how effectively sawfish could be 
protected.

Habitat Usage

    At the time of listing, very little information was known about the 
habitat usage patterns of the species. The Status Review and the final 
listing rule identified habitat loss and degradation as the secondary 
cause of the species' decline. The primary reason for the species' 
decline was bycatch in various commercial and recreational fisheries.
    The Status Review (NMFS, 2000) described sawfish habitat usage as: 
``Sawfish in general inhabit the shallow coastal waters of most warm 
seas throughout the world. They are found very close to shore in muddy 
and sandy bottoms, seldom descending to depths greater than 32 ft (10 
m). They are often found in sheltered bays, on shallow banks, and in 
estuaries or river mouths.'' In the years since the status review, 
additional research on habitat use by smalltooth sawfish has been 
undertaken. This research confirmed this general characterization for 
smalltooth sawfish and has revealed a more complex pattern of habitat 
use than previously known, with different life history stages having 
different patterns of habitat use.
    A variety of methods have been applied to studying habitat use 
patterns of smalltooth sawfish, including acoustic telemetry 
(Simpfendorfer, 2003), acoustic monitoring (Simpfendorfer, unpublished 
data; Poulakis, unpublished data), public encounter databases (Seitz 
and Poulakis, 2002; Poulakis and Seitz, 2004; Simpfendorfer and Wiley, 
2005), and satellite archival tagging (Simpfendorfer and Wiley, 2005b). 
The majority of this research has targeted juvenile sawfish, but some 
information on adult habitat use has also been obtained.
    Encounter databases also provide insight into the habitat use 
patterns of smalltooth sawfish. MML, Florida Fish and Wildlife Research 
Institute (FWRI, formerly managed by Poulakis and Seitz), and the 
Florida Museum of Natural History (FLMNH) manage encounter databases 
containing data on sightings and captures of smalltooth sawfish from 
commercial and recreational fishermen, research efforts, and other 
sources (e.g., divers and boaters). To request reporting of sightings/
captures from the public, MML, FWRI, and FLMNH have engaged in various 
outreach efforts. These efforts include placing flyers at boat ramps 
and tackle/dive shops, media releases, articles in fishing magazines, 
interviews with recreational fishing guides and commercial fisheries, 
websites, and personal contacts with researchers. Standard 
questionnaires are used to collect encounter data (water depth, 
location, tidal states, gear information, size of animal, and various 
other physical and environmental features). Outreach efforts were 
initially focused primarily in Florida but have expanded into areas 
along the southeastern coasts of the United States between Texas and 
North Carolina. The bulk of the reports of smalltooth sawfish sightings 
and/or captures occur primarily in Florida between Charlotte Harbor and 
Florida Bay.
    Based on our historic and current knowledge of where smalltooth 
sawfish are encountered (coastal areas), we believe recreational 
fishers who primarily fish in coastal areas represent the best source 
of data for the species. Additionally, Simpfendorfer and Wiley (2005) 
analyzed the number of registered fishers in Florida by county to see 
if fishing effort affects the distribution of the encounters. No strong 
correlation between the distribution of fishers and the encounter 
locations was found. Based on Simpfendorfer and Wiley (2005), we 
believe that the encounter data is not geographically biased.
    The second largest source of encounter data is directed-research 
programs conducted by FWRI, MML, and NMFS. Directed-research efforts on 
the species are also primarily focused in coastal areas but are limited 
to southwest Florida between Charlotte Harbor and the Florida Keys. The 
sampling methodologies for the directed research efforts are not random 
or stratified: research efforts are focused in areas where sawfish have 
been encountered, primarily southwest Florida. We anticipate future 
sampling efforts for these and other areas will use a random-stratified 
approach. Research is underway to determine habitat usage patterns, 
site fidelity, movement patterns, and various genetic relationships.
    Encounter and research data provide some insight into adult 
smalltooth sawfish habitat usage patterns. Data on adult male (at least 
134 in [340 cm] in length) and adult female (142 in [360 cm] in length) 
smalltooth sawfish is very limited. Information on adult smalltooth 
sawfish comes from encounter data, observers aboard fishing vessels, 
and pop-up satellite archival (PAT) tags. The encounter data suggest 
that adult sawfish occur from shallow

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coastal waters to deeper shelf waters. Poulakis and Seitz (2004) 
observed that nearly half of the encounters with adult-sized sawfish in 
Florida Bay and the Florida Keys occurred in depths from 200 to 400 ft 
(70 to 122 m). Simpfendorfer and Wiley (2005) also reported encounters 
in deeper water off the Florida Keys, noting that these were mostly 
reported during winter. Observations on commercial longline fishing 
vessels and fishery independent sampling in the Florida Straits show 
large sawfish in depths of up to 130 ft (40 m) (Carlson and Burgess, 
unpublished data).
    Seitz and Poulakis (2002) reported that one adult-sized animal, 
identifiable by its broken rostrum, was captured in the same location 
over a period of a month near Big Carlos Pass. This suggests that 
adults may have some level of site fidelity for relatively short 
periods; however, the historic occurrence of seasonal migrations along 
the U.S. East Coast also suggests that adults may be more nomadic than 
juveniles with their distribution controlled, at least in part, by 
water temperature.
    In summary, there is limited information on adult sawfish 
distribution and habitat use. Adult sawfish are encountered in various 
habitat types (mangrove, reef, seagrass, and coral), in varying 
salinity regimes and temperatures, and at various water depths. Adults 
are believed to feed on a variety of fish species and crustaceans. No 
known breeding sites have been identified. Encounter data have 
identified river mouths as areas where many people observe both 
juvenile and adult sawfish. Seitz and Poulakis (2002) noted that many 
of the encounters occurred at or near river mouths in southwest 
Florida. Simpfendorfer and Wiley (2005b) reported a similar pattern of 
distribution along the entire west coast of Florida. Along the 
Everglades coastal region, Simpfendorfer and Wiley (2005) report a 
strong association of smalltooth sawfish with the Chatham, Lostmans, 
Rodgers, Broad, Harney, and Shark Rivers.
    Most of the research and encounter data on habitat usage of 
smalltooth sawfish has been obtained on juveniles that are less than 79 
in (200 cm). Juveniles in this size class are most susceptible to 
predation and starvation (Simpfendorfer, 2006). Like other species of 
elasmobranchs, smalltooth sawfish appear to use nursery areas because 
of the reduced numbers of predators and abundant food resources 
(Simpfendorfer and Milward, 1993).
    Much of the research on smalltooth sawfish juveniles indicates some 
differences in habitat use based on the length of the animals, between 
what are characterized as very small (less than 39 in [100 cm]) and 
small (39-79 in [100-200] cm) juveniles. Most encounters of both very 
small and small juveniles have been within 1,641 ft (500 m) of shore 
(Simpfendorfer, 2006).
    Very small juvenile smalltooth sawfish show high levels of site 
fidelity, at least over periods of days and potentially for much longer 
(Simpfendorfer, 2003 and 2006). Limited acoustic tracking studies (less 
than five animals) have shown that, at this size, sawfish will remain 
associated with the same shallow mud bank over periods of several days 
(Simpfendorfer, 2003). Very small juveniles spend a large portion of 
their time on the same shallow mud or sand banks in water less than 1 
ft (30 cm) deep. Since water levels on individual mud banks vary with 
the tide, the movements of these small animals appear to be directed 
toward remaining in shallow water. The mud banks are very small and 
preliminary home range size for the tracked animals is estimated to be 
1,076 -10,763 ft2 (100-1,000 m2) (Simpfendorfer, 2003). The longer-term 
fidelity to these sites is poorly understood, and ongoing research is 
expected to provide more insight into determining how much habitat very 
small juveniles use on a daily basis. Simpfendorfer (2001) concludes 
that shallow coastal waters represent key habitat for the species, and 
in particular that waters less than 3.3 ft (1 m) may be very important 
as nursery areas. The primary purpose of staying in such shallow water 
is likely to avoid predators, such as bull sharks. Additionally, these 
shallow waters may provide warm water temperatures that may be utilized 
to maximize growth rates (Simpfendorfer, 2006). Simpfendorfer (2001) 
concludes that most smalltooth sawfish (adults and juveniles) show a 
preference for water temperatures greater than 17.8[deg] C (64[deg] F).
    In addition to shallow mud banks, very small juveniles also use red 
mangrove prop root habitats in southern Florida (Simpfendorfer and 
Wiley, 2005). Animals in this size class spend the vast majority of 
their time in very shallow water less than 1 ft (30 cm) deep, and they 
tend to move into mangrove prop roots during periods of high tide. Red 
mangrove habitats also provide foraging opportunities for very small 
and small juveniles, because the prop root system provides nursery 
areas for various fish and crustacean species.
    Small juveniles have many of the same habitat use characteristics 
seen in the very small sawfish. Their association with very shallow 
water (less than 1 ft [30 cm] deep) is slightly weaker, possibly 
because they are better suited to predator avoidance due to their 
larger size and greater experience (NMFS, 2006). They do still have a 
preference for shallow water, remaining in depths mostly less than 3.3 
ft (1 m). Most encounters of small juveniles also occur near red 
mangroves. Site fidelity has also been studied on small juvenile 
sawfish. Several sawfish, approximately 59 in (150 cm) in length and 
fitted with acoustic tags, have been relocated in the same general 
areas over periods of several months, suggesting a high level of site 
fidelity (Simpfendorfer 2003). The daily home range for these animals, 
based on data from a few animals, appears to be much larger than that 
of very small juveniles (e.g., 10,763,910-53,819,552 ft\2\ [1-5 
km\2\]). The recent implementation of acoustic monitoring systems to 
study the longer term site fidelity of sawfish has confirmed these 
observations and also indicates that changes in environmental 
conditions (salinity) may be important in driving changes in local 
distribution and, therefore, habitat use patterns (Simpfendorfer, 
unpublished data).
    Simpfendorfer and Wiley (2005) documented that no encounters 
occurred within habitat in permanent freshwater areas. Many encounters 
occur near river mouths or near sources of freshwater inflow and 
encounter data suggests that estuarine habitats may be an important 
factor affecting the species' distribution. Simpfendorfer (2001) 
suggests the reason smalltooth sawfish occur in river mouth areas may 
be due to the lower salinity, submerged vegetation, or because prey may 
be abundant. We analyzed (MML and FWRI) encounter data from 1998-2008 
for juveniles and the data indicates the majority of the juvenile 
encounters occur within euryhaline or estuarine waters. Euryhaline/
estuarine waters are highly productive areas that contain a variety of 
food sources for the smalltooth sawfish. Mullet, clupeids, and various 
crustacean species that are known food sources for the smalltooth 
sawfish are commonly found in estuarine areas.
    Juvenile smalltooth sawfish may require specific salinity regimes 
with specific freshwater inputs but at this time data on specific 
salinity regime requirements for the species does not exist. Ongoing 
studies of habitat use patterns of very small and small juveniles in 
the Caloosahatchee River are expected to provide more insight into the 
habitat used by or necessary for an individual juvenile (less than or

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equal to 79 in [200 cm] in length) smalltooth sawfish. At this time, 
however, there is insufficient data available to determine whether 
specific salinity ranges are requirements of small juveniles.
    Data on large (greater than 79 in [200 cm] in length) juvenile 
smalltooth sawfish is limited, and more information is needed to 
determine the habitat usage patterns and site fidelity characteristics 
of this size class of smalltooth sawfish.

Critical Habitat Identification and Designation

    Critical habitat is defined by section 3 of the ESA as ``(i) the 
specific areas within the geographical area occupied by the species, at 
the time it is listed in accordance with the provisions of section 1533 
of this title, on which are found those physical or biological features 
(I) essential to the conservation of the species and (II) which may 
require special management considerations or protection; and (ii) 
specific areas outside the geographical area occupied by the species at 
the time it is listed in accordance with the provisions of section 1533 
of this title, upon a determination by the Secretary that such areas 
are essential for the conservation of the species.'' This definition 
provides us with a step-wise approach to identifying areas that may be 
designated as critical habitat for the endangered smalltooth sawfish.

Geographical Area Occupied by the Species

    The best available scientific and commercial data identifies the 
geographical area occupied by the smalltooth sawfish at the time of 
listing (April 1, 2003) as peninsular Florida. We have interpreted 
``geographical area occupied'' in the definition of critical habitat as 
the range of the species at the time of listing (45 FR 13011; February 
27, 1980). The range was delineated at the time of listing from data 
provided by existing literature and encounter data. Because only a few 
contemporary encounters (one in Georgia, one in Alabama, and one in 
Louisiana) have been documented outside of Florida since 1998, we 
consider peninsular Florida to be the species' occupied range at the 
time of listing. At this time, we do not consider these limited 
observations as indicating that the species has re-established either 
its occupation of Gulf coast states or its seasonal migrations up the 
east coast of the U.S. outside of Florida.

Specific Areas Containing Physical or Biological Features Essential to 
Conservation

    The definition of critical habitat further instructs us to identify 
the specific areas on which are found the physical or biological 
features essential to the species' conservation. Our regulations state 
that critical habitat will be defined by specific limits using 
reference points and lines on standard topographic maps of the area, 
and referencing each area by the State, county, or other local 
government unit in which it is located (50 CFR 424.12(c)).
    According to the definition of critical habitat, the physical and 
biological features essential to conservation must be identified 
(hereafter also referred to as ``essential features''). Section 3 of 
the ESA (16 U.S.C. 1532(3)) defines the terms ``conserve,'' 
``conserving,'' and ``conservation'' to mean: ``to use, and the use of, 
all methods and procedures which are necessary to bring any endangered 
species or threatened species to the point at which the measures 
provided pursuant to this chapter are no longer necessary.'' Our 
regulations at 50 CFR 424.12(b) provide guidance as to the types of 
habitat features that may be used to describe critical habitat.
    The draft recovery plan developed for the smalltooth sawfish 
represents the best judgment about the objectives and actions necessary 
for the species' recovery. We reviewed the draft recovery plan's 
habitat-based recovery objective for guidance on the habitat-related 
conservation requirements of the species. This objective identifies the 
need to protect and/or restore smalltooth sawfish habitats and 
discusses adult and juvenile habitats separately. Habitats, especially 
those that have been demonstrated to be important for juveniles, must 
be protected and, if necessary, restored. Protected, suitable habitat 
throughout the species' range will be necessary to support recruitment 
of young individuals to the recovering population. Without sufficient 
habitat, the population is unlikely to increase to a level associated 
with low extinction risk and delisting.
    The draft recovery plan also identifies specific recovery criteria 
that must be met to satisfy each objective. As stated in the plan, 
adult habitat-based recovery criteria for the species require the 
identification and protection of adult aggregation, mating, and/or 
pupping areas. Information on historic aggregation, mating, and/or 
pupping sites does not exist. Currently, no aggregation or mating areas 
have been identified for adults. Additionally, no information is 
available on specific pupping locations for gravid females. Tracking 
data on gravid females is lacking, but newborn juveniles still 
possessing their protective sheaths and newly pupped animals have been 
documented close to shore. Encounter and site fidelity data suggest 
juveniles are pupped in these areas, but this has not been validated. 
No known specific areas where adults perform any particular function, 
including feeding, are known. Adults are considered opportunistic 
feeders and forage on a variety of fish and crustacean species. Based 
on the available information on the habitat usage patterns of adults, 
we cannot identify physical or biological features essential to the 
species' conservation, or identify any areas on which such features may 
be found.
    In contrast to the paucity of information available on adult 
smalltooth sawfish, more detailed information on habitat usage patterns 
of juveniles is available, and more specific habitat-based recovery 
criteria are identified in the recovery plan. The habitat-based 
recovery criterion for juveniles identifies mangrove shorelines, non-
mangrove nursery habitats, and freshwater flow regimes as important 
features for juveniles. As stated earlier, the habitat-based recovery 
objective for the species focuses on protecting areas that have been 
identified as important for juveniles (i.e., nurseries). This objective 
also stresses the need to protect suitable habitats for juveniles to 
support their recruitment into the population. Juveniles are especially 
vulnerable to predation and starvation (Simpfendorfer and Wiley, 2005). 
Protection of the species' nurseries is crucial because the rebuilding 
of the population cannot occur without protecting the source (juvenile) 
population and its associated habitats. The recovery plan states that 
the recovery of the smalltooth sawfish depends on the availability and 
quality of nursery habitats and that protection of high-quality nursery 
habitats located in southwest Florida is essential to the species.
    We conclude that facilitating recruitment into the population by 
protecting the species' juvenile nursery areas is the key conservation 
objective for the species that will be supported by the designation of 
critical habitat.
    As stated in the recovery plan, smalltooth sawfish, like many 
sharks and rays, use specific habitats commonly referred to as 
nurseries or nursery areas. The recovery plan does not identify 
specific locations for

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nursery areas but does state that protecting nursery areas within 
southwest Florida is important to the recovery of the species. Nursery 
areas in addition to those in southwest Florida are also identified as 
important for recovery but locations of these additional areas were not 
specified. Thus, to identify specific areas that may meet the 
definition of critical habitat, we focused on specifically defining 
what constitutes a ``nursery'' area for smalltooth sawfish. We then 
identified those physical or biological features that are essential to 
the conservation of the species because they provide nursery area 
functions to the species in these areas.
    We evaluated information in the draft recovery plan, historical 
information on habitat use by sawfish, and available encounter data and 
scientific literature, as well as sought expert opinion, to determine 
where or what constitutes a ``nursery area'' for the species. 
Historical information on the species only provides limited, mostly 
anecdotal, information on the location of juvenile animals and does not 
discuss specific habitat usage patterns for them. Historical 
information indicates that juveniles were found in the lower reaches of 
the St. Johns River, the Indian River Lagoon, southwest Florida, and in 
areas along the Gulf coast between Florida and Texas. Using historic 
location information alone would not provide a reasonable basis for 
identification of nursery areas, given the qualitative nature of the 
information. Further, because most of these areas have been so 
physically altered, conditions present historically may not be present 
today, and thus features that may have provided nursery area functions 
in the past may be absent.
    We then reviewed juvenile encounter data from the MML and FWRI 
databases to see whether the data alone indicates the existence of 
nursery areas. In summary, juvenile sawfish have been encountered in 
the Florida Panhandle, the Tampa Bay area, in Charlotte Harbor and the 
Caloosahatchee River, throughout the Everglades region and Florida Bay, 
the Florida Keys, and in scattered locations along the east coast of 
Florida south of the St. Johns River. However, apart from the Charlotte 
Harbor, Caloosahatchee River, and Ten Thousand Islands/Everglades (TTI/
E) areas, many of these encounters are represented by a single 
individual in a single year.
    Heupel et al. (2007) are critical of defining nursery areas for 
sharks and related species such as sawfish based solely on the presence 
of single occurrences of individual juvenile fish. Instead, these 
authors argue that nursery areas are areas of increased productivity 
which can be evidenced by natal homing or philopatry (use of habitats 
year after year) and that juveniles in such areas should show a high 
level of site fidelity (remain in the area for extended periods of 
time). Heupel et al. (2007) propose that shark nursery areas can be 
defined based on three primary criteria: (1) juveniles are more common 
in the area than other areas, i.e., density in the area is greater than 
the mean density over all areas; (2) juveniles have a tendency to 
remain or return for extended periods (weeks or months), i.e., site 
fidelity is greater than the mean site fidelity for all areas; and (3) 
the area or habitat is repeatedly used across years whereas other areas 
are not. Scattered and infrequent occurrences of juveniles may indicate 
a lack of features that provide the necessary functions of a nursery 
area, and an area with only scattered or infrequent occurrences is not 
viewed by the authors as constituting a nursery area. Heupel et al. 
(2007) do not assume that that all sharks have nursery areas. The 
authors discuss that size-at-birth, rate of growth, time to maturity, 
litter size and frequency of breeding may be important factors 
dictating whether a shark species utilizes a nursery or not. Shark 
species with high growth rates, early maturity, and annual reproduction 
may not benefit as much from utilizing a nursery area. In contrast, the 
authors predict that species that have small size at birth and slow 
juvenile growth rates may be more likely to utilize nursery areas 
because they may be more susceptible to juvenile predation. We believe 
this paper provides the best framework for defining a ``nursery area'' 
for the smalltooth sawfish because they are small at birth, slow to 
mature, and existing data on tracked juveniles indicates their limited 
movements and ranges are directed toward avoiding predation by sharks 
foraging in deeper waters.
    Using the Heupel et al. (2007) framework, we evaluated our juvenile 
encounter data for patterns in juvenile density, site fidelity, and 
repeat usage over years. Encounter data indicate three types of 
distributions of individual juvenile sawfish. The first group consists 
of scattered or single encounters. Encounters occurring in areas north 
of Charlotte Harbor, including a few in the panhandle of Florida and 
along the east coast of Florida, are included in this group. Encounters 
in these areas were scattered individual encounters, and no indication 
of repeat or multiple use of an area was evident. The second group of 
encounters consists of encounters that had multiple individuals in an 
area, but these encounters were geographically scattered and not 
repeated over years. These encounters occurred in the Florida Keys. 
Encounters in this group were located on different sides of various 
Keys, and no consistent or continuous pattern of repeat usage over 
years could be identified. In fact, in 2006, juvenile encounters were 
largely lacking throughout much of the Keys. The third group of 
encounters exhibit repeat usage of the same location by both single and 
multiple individuals, higher density of encounters than the other 
groups, and usage occurring year after year. These encounters occurred 
in areas from Charlotte Harbor south through the Everglades and Florida 
Bay.
    Based on this analysis, the juvenile encounters in the third 
grouping discussed above, from Charlotte Harbor through the Everglades, 
are the only encounters that suggest these areas meet the nursery area 
criteria set forth by Heupel et al. (2007). Juvenile sawfish are more 
commonly encountered in these areas than in other areas, i.e. density 
in the area is greater than the mean density over all areas, and the 
area is repeatedly used across years, whereas others are not. Available 
information about site fidelity of juveniles is limited and does not 
allow quantitative comparisons between the apparent nursery areas and 
all other areas. However, as discussed above, available information 
indicates that small and very small juveniles show high fidelity to 
shallow nearshore areas where they have been acoustically tracked. Data 
from juveniles tracked in the TTI/E area indicate they exhibit site 
fidelity and residency patterns between 15 and 55 days (Wiley and 
Simpfendorfer, 2007). Tracking data also suggests that juveniles 
exhibit specific movement patterns to avoid predation. A juvenile 
tracked in the Everglades National Park (ENP) in the Shark River spent 
its time moving between a shallow mud bank during low tide and mangrove 
roots during high tide (Simpfendorfer, 2003). Tracking data in Mud Bay 
(ENP) and Faka Union Bay (TTI) indicate juveniles remain in very 
shallow waters, 0.9 ft (0.3 m) over several weeks. Tracking data in the 
Charlotte Harbor Estuary is limited to the Caloosahatchee River and its 
adjacent canals. Juvenile tracking data from a 60 in (153 cm) juvenile 
indicates that the animal remained within water depths less than 3 ft 
(0.9 m) along a highly modified shoreline (Simpfendorfer, 2003). 
Tracking data

[[Page 70296]]

indicates the animal spent the majority of its time within man-made 
canals and adjacent to docks and marinas within the river.
    Juvenile encounters outside of the area between Charlotte Harbor 
and the Everglades and Florida Bay do not fit the framework and are not 
considered nursery areas at this time. Anecdotal information indicates 
that juvenile size animals have been encountered throughout portions of 
their historic range, and our recovery plan indicates that the 
establishment of nursery areas outside of southwest Florida is 
necessary for the species to recover. However, we cannot determine at 
this time the temporal or spatial distribution of future sawfish 
nursery areas.
    To more specifically delineate the boundaries of the nursery area 
or areas, we utilized Geographical Information System (GIS) software to 
map the density of all juvenile (length less than or equal to 200cm) 
encounters (MML and FWRI) located along peninsular Florida within 500 m 
of land, documented between the years of 1998-2008, with all years 
combined. Two density maps were generated to determine the mean density 
for all encounters and the density for all encounters excluding the 
research encounters. We utilized 1km2 density grids (same grid size 
utilized by Simpfendorfer, 2006) to determine density levels and 
distributions. Juvenile densities were very similar between the two 
groups. However, to remove any bias from the research efforts, we 
utilized the juvenile density map excluding research effort. The 
overall nursery area between Charlotte Harbor and Florida Bay breaks 
naturally into two areas between Ten Thousand Islands and the 
Caloosahatchee River, based on a long stretch of sandy beach habitat in 
the Naples area that is lacking encounters with densities greater than 
the mean density overall. Next we mapped juvenile encounters in these 
two areas by year (1998-2008), to verify where repeat usage occurred 
over years. This produced several groupings of 1 km2 grids with higher 
mean juvenile densities compared to mean juvenile density throughout 
peninsular Florida: 1 grouping within Charlotte Harbor, 1 grouping 
encompassing the Caloosahatchee River, and 3 groupings from the Ten 
Thousand Islands area through Florida Bay. We do not believe either the 
Charlotte Harbor Estuary or the TTI/E nursery areas should be 
subdivided into multiple smaller nursery areas for several reasons. 
First, the Heupel et al. (2007), framework does not indicate how 
discrete nursery areas within a large area of juvenile use might be 
identified. Second, our knowledge about juvenile sawfish movements and 
ranges is very limited. Third, both areas consist of interconnected 
environmental systems and no environmental barriers exist to prohibit 
juvenile sawfish movement throughout the system. Finally, limiting 
nursery area boundaries to discrete habitat grids represented only by 
past encounters with juveniles would not best serve the conservation 
objective of facilitating population growth through juvenile 
recruitment. The specific boundaries of the two nursery areas were then 
derived by locating the nearest publicly identifiable boundary (e.g., 
boundaries of established parks or preserves) or structure external to 
the outermost boundary of the juvenile density grids where the mean 
density is greater than the density in the surrounding areas. We 
identified reference points and lines on standard topographic maps in 
the area to describe the specific boundary of the nursery areas.
    The Charlotte Harbor Estuary nursery area includes Charlotte 
Harbor, Gasparilla Sound, Pine Island Sound, Matlacha Pass, San Carlos 
Bay, Estero Bay, and the Caloosahatchee River in Charlotte and Lee 
Counties. The nursery area is defined by the following boundaries. It 
is bounded by the Peace River at the eastern extent at the mouth of 
Shell Creek and the northern extent of the Charlotte Harbor Preserve 
State Park. At the Myakka River the estuary is bounded by the SR-776 
Bridge and Gasparilla Sound at the SR-771 Bridge. The COLREGS-72 lines 
between Gasparilla Island, Lacosta Island, North Captiva Island, 
Captiva Island, Sanibel Island, and the northern point of Estero Island 
are used as the coastal boundary for the nursery area. The southern 
extent of the area is the Estero Bay Aquatic Preserve, which is bounded 
on the south by the Lee/Collier County line. Inland waters are bounded 
at SR-867 (McGregor Blvd) to Fort Myers, SR-80 (Palm Beach Blvd), 
Orange River Blvd, Buckingham Rd, and SR-80 to the west side of the 
Franklin Lock and Dam (S-79), which is the eastern boundary on the 
Caloosahatchee River and a structural barrier for sawfish access. 
Additional inland water boundaries north and west of the lock are 
bounded by North River Road, SR-31, SR-78 near Cape Coral, SR-765, US-
41, SR-35 (Marion Ave) in Punta Gorda, and Riverside Road to the 
eastern extent of the Peace River. The Charlotte Harbor nursery area is 
graphically displayed at the end of this document.
    The Ten Thousand Islands/Everglades (TTI/E) nursery area is located 
within Collier, Monroe, and Miami-Dade Counties, Florida. The 
Everglades nursery area includes coastal and inshore waters within 
Everglades National Park (ENP), including Florida Bay; in the vicinity 
of Everglades City; within the Cape Romano-Ten Thousand Islands Aquatic 
Preserve (AP); and within the portion of Rookery Bay AP south of SR-92. 
The boundaries match the portion of Rookery Bay AP south of SR-92, and 
the Cape Romano-Ten Thousand Islands Aquatic Preserve AP. The nursery 
area boundaries also match the ENP boundaries with following two 
exceptions. The nursery area boundary connects points 55 and 57, which 
extend beyond the ENP boundary to include accessible nursery areas. The 
nursery area boundary is located inside the ENP boundary between points 
77 and 2, omitting the northeastern portion of the ENP. The area is 
omitted because it is not accessible to sawfish. The TTI/E nursery area 
is graphically displayed at the end of this document.
    Having identified the nursery areas, we next identified the 
physical or biological features found in these areas that are essential 
to the species' conservation because they provide nursery area 
functions to the sawfish.
    Simpfendorfer (2006) analyzed MML's smalltooth sawfish encounter 
data to determine the importance of habitat factors to juveniles less 
than 79 in (200 cm) in length. Depth data is consistently reported by 
fishers and is accurately reported because most fishers use depth 
finders so depth data was extracted from the encounter database. 
Simpfendorfer (2006) examined the proximity of encounters to habitat 
features that could be evaluated from geographic information system 
(GIS) databases. These features were: mangroves (GIS mangrove coverages 
cannot distinguish between mangrove species), seagrasses, freshwater 
sources, and the shoreline. Simpfendorfer (2006) used GIS shapefiles 
for the features to determine the shortest distance from the encounter 
to the feature. The encounter data was converted to encounter density 
by gridding the data, and the results of the analysis were then used in 
a habitat suitability model. The model indicates that water depths less 
than 3 ft, mangrove buffers or shorelines, and euryhaline habitat areas 
(areas with wider salinity ranges and receiving freshwater input) have 
the strongest correlation with juvenile smalltooth sawfish encounters. 
Additionally, most encounters were documented within a distance of 1641 
ft (500 m) from shore. The Simpfendorfer (2006) model suggests that 
areas of high suitability for juvenile sawfish contain all three of 
these features. Large areas coded as

[[Page 70297]]

``highly suitable'' habitat for juveniles are located in the areas we 
determined meet the Heupel et al. (2007) framework criteria for a 
nursery area, as applied to the sawfish.
    Based on the natural history of the species, its habitat needs and 
the key conservation objective of protecting juvenile nursery areas, 
two physical and biological features are identified as essential to the 
conservation of the smalltooth sawfish because they provide nursery 
area functions. The two features are: red mangroves and shallow 
euryhaline habitats characterized by water depths between the Mean High 
Water line and 3 ft (0.9 m) measured at Mean Lower Low Water (MLLW). As 
discussed above, the prop root system and the location of red mangroves 
(close to shore), and shallow water depths provide refuge from 
predators. Red mangroves and shallow mud or sand bank euryhaline 
habitats are also highly productive and provide ample, diverse foraging 
resources. Among elasmobranchs, smalltooth sawfish are one of the few 
species known to inhabit euryhaline habitats which may provide several 
benefits for the species. Euryhaline habitats are very productive 
environments that support an abundance and variety of prey resources 
that can only be accessed by species that inhabit their systems. 
Additionally, the risk of predation may be reduced in these euryhaline 
habitats because potential predators (sharks) may be incapable of 
inhabiting these habitats.
    Based on the best available information, we conclude red mangroves 
and adjacent shallow euryhaline habitats and the nursery area functions 
they provide facilitate recruitment of juveniles into the adult 
population. Thus, these features are essential to the conservation of 
the smalltooth sawfish. While some studies cite 1.0 meter as the 
preferred depth limit, others (Simpfendorfer, 2006), cite 3.0 ft. For 
this rule, the water depth feature will be defined as 3 ft (0.9 m) 
because the NOAA Navigational Charts depth contour lines and most GIS 
databases utilize English units of measure.
    Based upon the best available information, we cannot conclude that 
any other sufficiently definable features of the environment in the two 
nursery areas, other than red mangroves and adjacent shallow euryhaline 
habitats, are essential to smalltooth sawfish conservation.
    Based on the boundaries of the two nursery areas and GIS data 
information on the location of the features, the Charlotte Harbor 
Estuary and the TTI/E nursery areas contain the features essential to 
the conservation of smalltooth sawfish because they facilitate 
recruitment into the adult population. In this rule, we propose to 
designate these two specific areas, referred to as critical habitat 
``units,'' as critical habitat for the smalltooth sawfish.
    There are areas outside of the two nursery areas, including areas 
on the east and west coasts of Florida that contain some of the same 
features identified as essential features in our two proposed nursery 
areas. Habitat areas outside the specific nursery areas also meet 
Simpfendorfer's (2006) classification of highly suitable habitat for 
juveniles because they contain these features, notably areas in Tampa 
Bay and in the Indian River Lagoon. Because the features are essential 
to the conservation of the species based on the nursery functions they 
provide, we determined that these features are essential to the 
conservation of smalltooth sawfish only when present in nursery areas. 
None of these other areas meet the Heupel et al. (2007) definition of a 
nursery area. Encounters in these areas are rare and no pattern of 
repeat usage could be identified. Lack of repeat or high-density usage 
of these other areas by juveniles may be a function of the limited 
current size of a reproducing population that does not yet need 
additional nursery areas. Even so, we have no basis to conclude that 
other areas, even those containing shallow euryhaline habitats and 
mangroves, will be used as nursery areas in the future. Nursery areas 
cannot be located based solely on the co-location of shallow depths and 
euryhaline salinity regimes, and juveniles are not commonly or 
repeatedly found everywhere the features are present. Mangroves may 
also not be determinative of nursery area function for the sawfish; the 
Florida Keys contain mangrove resources, yet juvenile sawfish use of 
the Keys as evidenced by encounter data has been highly variable, 
including near absence in certain recent years. Additionally, historic 
anecdotal information on locations of small animals suggests they were 
found in the lower St. Johns River which does not support mangroves. 
Based on the best available scientific information, we identified two 
specific areas for the species where these features provide nursery 
functions and are therefore essential to the conservation of the 
species. We therefore propose to designate the Charlotte Harbor Estuary 
and TTI/E Units.
    The boundaries of the two specific areas are the same as the 
Charlotte Harbor Estuary and TTI/E nursery area boundaries. GIS 
bathymetry data, mangrove coverage data, and salinity data were used to 
verify the distribution of the essential features within the nursery 
areas. We have identified reference points and lines on standard 
topographic maps of the areas to describe the specific boundaries of 
the two units in the proposed regulatory text.
    The essential features can be found unevenly dispersed throughout 
the two areas. The limits of available information on the distribution 
of the features, and limits on mapping methodologies, make it 
infeasible to define the specific areas containing the essential 
features more finely than described herein. Existing man-made 
structures such as boat ramps, docks, pilings, maintained channels or 
marinas do not provide the essential features that are essential for 
the species' conservation and are thus not proposed as critical 
habitat. Areas not accessible (i.e., areas behind water control 
structures) to sawfish are not part of this designation. As discussed 
here and in the supporting impacts analysis, given the specificity of 
the essential features, determining whether an action may affect one or 
both of the features can be accomplished without entering into an ESA 
section 7 consultation.

Unoccupied Areas

    ESA section 3(5)(A)(ii) further defines critical habitat to include 
specific areas outside the geographical area occupied if the areas are 
determined by the Secretary of Commerce (Secretary) to be essential for 
the conservation of the species. Regulations at 50 CFR 424.12(e) 
specify that we shall designate as critical habitat areas outside the 
geographical area presently occupied by a species only when a 
designation limited to its present range would be inadequate to ensure 
the conservation of the species. Habitat based recovery criteria in the 
recovery plan suggest areas outside the current occupied range may be 
important to the species' recovery. However, based on the best 
available information we cannot identify unoccupied areas that are 
currently essential to the conservation of the species. If information 
on essential features or habitats for the species becomes available, we 
will consider revising this critical habitat designation.

Special Management Considerations or Protection

    Specific areas within the geographical area occupied by a species 
may be designated as critical habitat only if they

[[Page 70298]]

contain physical or biological features essential to the conservation 
of the species that ``may require special management considerations or 
protection.'' A few courts have interpreted aspects of this statutory 
requirement, and the plain language aids in its interpretation. For 
instance, the language clearly indicates the features, not the specific 
area containing the features, are the focus of the ``may require'' 
provision. Use of the disjunctive ``or'' also suggests the need to give 
distinct meaning to the terms ``special management considerations'' and 
``protection.'' Generally speaking, ``protection'' suggests actions to 
address a negative impact or threat of a negative impact. 
``Management'' seems plainly broader than protection, and could include 
active manipulation of a feature or aspects of the environment. Two 
Federal district courts, focusing on the term ``may,'' ruled that 
features can meet this provision based on either present requirements 
for special management considerations or protections, or on possible 
future requirements. See Center for Biol. Diversity v. Norton, 240 F. 
Supp. 2d 1090 (D. Ariz. 2003); Cape Hatteras Access Preservation 
Alliance v. DOI, 344 F. Supp. 108 (D.D.C. 2004). The Arizona district 
court ruled that the provision cannot be interpreted to mean that 
features already covered by an existing management plan must be 
determined to require ``additional'' special management, because the 
term ``additional'' is not in the statute. Rather, the court ruled that 
the existence of management plans may be evidence that the features in 
fact require special management. Center for Biol. Diversity v. Norton, 
1096-1100. NMFS' regulations define ``special management considerations 
or protections'' to mean ``any methods or procedures useful in 
protecting physical and biological features of the environment for the 
conservation of listed species'' (50 CFR 424.02(j)).
    Based on the above, we evaluated whether the essential features 
proposed in this document may require special management considerations 
or protections by evaluating four criteria:
    (a) Whether there is presently a need to manage the feature;
    (b) Whether there is the possibility of a need to manage the 
feature;
    (c) Whether there is presently a negative impact on the feature; or
    (d) Whether there is the possibility of a negative impact on the 
feature.
    In evaluating present or possible future management needs for the 
features, we recognized that the features in their present condition 
must be the basis for a finding that these are essential to the 
smalltooth sawfish's conservation. In addition, the needs for 
management evaluated in (a) and (b) were limited to managing the 
features for the conservation of the species. In evaluating whether the 
essential features meet either criterion (c) or (d), we evaluated 
direct and indirect negative impacts from any source (e.g., human or 
natural). However, we only considered the criteria to be met if impacts 
affect or have the potential to affect the aspect of the feature that 
makes it essential to the conservation of the species. We also 
evaluated whether the features met the ``may require'' provision 
separately for the two ``specific areas'' proposed for designation.
    Red mangroves and adjacent shallow euryhaline habitats are 
susceptible to impacts from human activities because they are located 
in areas where urbanization occurs. The Status Review (NMFS, 2000) 
states that habitat destruction is one of the key factors affecting the 
present range of the species. The continued urbanization of the 
southeastern U.S. has resulted in substantial habitat losses for the 
species. Coastal areas where these features are located are subject to 
various impacts from activities including, but not limited to, dredging 
and disposal activities, coastal maritime construction, land 
development, and installation of various submerged pipelines. The 
impact from these activities combined with natural factors (e.g., major 
storm events) can significantly affect the quality and quantity of the 
two features listed above and their ability to provide nursery area 
functions (i.e., refuge from predators and abundant food resources), to 
juvenile smalltooth sawfish to facilitate recruitment into the 
population. Dredging projects modify water depths to accommodate 
navigation needs, mangroves are removed to construct docks and various 
maritime structures, and water control structures are installed to 
modify water flows in various areas, which can alter salinity regimes 
downstream. Based on our past ESA section 7 consultation database 
records we know that coastal areas in southwest Florida will continue 
to experience impacts from coastal construction projects and that these 
features will continue to experience negative impacts in the future. 
Based on our past consultation history, fewer Federal actions may 
affect habitats in the TTI/E Unit than in the Charlotte Harbor Estuary 
Unit, because much of the TTI/E Unit is held in public ownership by the 
Department of Interior. However, coastal storm impacts to mangroves, 
salinity, and water depth still occur within this area, and salinity 
regimes as well as mangroves in this area may be altered in the future 
by projects implemented under the Comprehensive Everglades Restoration 
Project. Thus, the two essential features currently need and will 
continue to need special management and protection in both of the two 
specific areas.

Application of ESA Section 4(a)(3)(B)(i)

    Section 4(a)(3)(B) prohibits designating as critical habitat any 
lands or other geographical areas owned or controlled by the Department 
of Defense (DOD), or designated for its use, that are subject to an 
integrated natural resources management plan (INRMP), if we determine 
that such a plan provides a benefit to the sawfish species (16 U.S.C. 
1533(a)(3)(B)). We solicited information from DOD, and received 
information indicating that no DOD facilities or managed areas are 
located within the specific areas identified as proposed critical 
habitat.

Application of ESA Section 4(b)(2)

    The foregoing discussion described the specific areas within U.S. 
jurisdiction that fall within the ESA section 3(5) definition of 
critical habitat because they contain the physical and biological 
features essential to the sawfish's conservation that may require 
special management considerations or protection. Before including areas 
in a designation, section 4(b)(2) of the ESA requires the Secretary to 
consider the economic, national security, and any other relevant 
impacts of designation of any particular area. Additionally, the 
Secretary has the discretion to exclude any area from designation if he 
determines the benefits of exclusion (that is, avoiding some or all of 
the impacts that would result from designation) outweigh the benefits 
of designation based upon the best scientific and commercial data 
available. The Secretary may not exclude an area from designation if 
exclusion will result in the extinction of the species. Because the 
authority to exclude is discretionary, exclusion is not required for 
any particular area under any circumstances.
    The analysis of impacts below summarizes the comprehensive analysis 
contained in our Draft Section 4(b)(2) Report, considering the 
economic, national security, and other relevant impacts that we 
projected would result from including the two units in the proposed 
critical habitat designation. This consideration informed our

[[Page 70299]]

decision on whether to exercise our discretion to propose excluding 
particular areas from the designation. Both positive and negative 
impacts were identified and considered (these terms are used 
interchangeably with benefits and costs, respectively). Impacts were 
evaluated in quantitative terms where feasible, but qualitative 
appraisals were used where that was more appropriate to particular 
impacts.
    The ESA does not define what ``particular areas'' means in the 
context of section 4(b)(2), or the relationship of particular areas to 
``specific areas'' that meet the statute's definition of critical 
habitat. As there was no biological basis to subdivide the two specific 
critical habitat units into smaller units, we treated these units as 
the ``particular areas'' for our initial consideration of impacts of 
designation.

Impacts of Designation

    The primary impacts of a critical habitat designation result from 
the ESA section 7(a)(2) requirement that Federal agencies ensure their 
actions are not likely to result in the destruction or adverse 
modification of critical habitat. Determining these impacts is 
complicated by the fact that section 7(a)(2) also requires that Federal 
agencies ensure their actions are not likely to jeopardize the species' 
continued existence. An incremental impact of designation is the extent 
to which Federal agencies modify their proposed actions to ensure they 
are not likely to destroy or adversely modify the critical habitat 
beyond any modifications they would make because of listing and the 
jeopardy prohibition. When a modification would be required due to 
impacts to both the species and critical habitat, the impact of the 
designation may be co-extensive with the ESA listing of the species. 
The nature of the sawfish and the proposed essential features, and the 
type of projects predicted to occur in the future in the areas proposed 
for designation, allowed us to identify incremental impacts of the 
proposed designation. The Draft Section 4(b)(2) Report identifies 
incremental cost and benefits that may result from the designation. 
Additional impacts of designation include state and local protections 
that may be triggered as a result of designation, and positive impacts 
that may arise from avoiding destruction or adverse modification of the 
species' habitat, and education of the public to the importance of an 
area for species conservation.
    The Draft Section 4(b)(2) Report describes the impacts analysis in 
detail (NMFS, 2008). The report describes the projected future Federal 
activities that would trigger section 7 consultation requirements 
because they may affect one or both of the essential features. 
Additionally, the report describes the project modifications we 
identified that may reduce impacts to the essential features. The