[Federal Register Volume 82, Number 181 (Wednesday, September 20, 2017)]
[Rules and Regulations]
[Pages 43885-43896]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-20069]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[Docket No. FWS-R4-ES-2016-0037; 4500030113]
RIN 1018-BB55
Endangered and Threatened Wildlife and Plants; Threatened Species
Status for Pearl Darter
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Final rule.
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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), determine
threatened species status under the Endangered Species Act of 1973
(Act), as amended, for the pearl darter (Percina aurora), a fish whose
historical range includes Mississippi and Louisiana. The effect of this
regulation will be to add this species to the List of Endangered and
Threatened Wildlife.
DATES: This rule becomes effective October 20, 2017.
ADDRESSES: This final rule is available on the internet at http://www.regulations.gov in Docket No. FWS-R4-ES-2016-0037 and on the
Mississippi Field Office Web site at https://www.fws.gov/mississippiES/. Comments and materials we received, as well as
supporting documentation we used in preparing this rule, are available
for public inspection at http://www.regulations.gov and by appointment,
during normal business hours at: U.S. Fish and Wildlife Service,
Mississippi Ecological Services Field Office, 6578 Dogwood View
Parkway, Jackson, Mississippi 39213, by telephone 601-321-1122 or by
facsimile 601-965- 4340.
FOR FURTHER INFORMATION CONTACT: Stephen Ricks, Field Supervisor, U.S.
Fish and Wildlife Service, Mississippi Ecological Services Field
Office, 601-321-1122. Persons who use a telecommunications device for
the deaf (TDD) may call the Federal Relay Service at 800-877-8339.
SUPPLEMENTARY INFORMATION:
Executive Summary
Why we need to publish a rule. Under the Endangered Species Act of
1973, as amended (Act, 16 U.S.C. 1531 et seq.), if we determine that a
species is an endangered or threatened species throughout all or a
significant portion of its range, we are required to promptly publish a
proposal in the Federal Register and make a determination on our
proposal within 1 year. Listing a species as an endangered or
threatened species can only be completed by issuing a rule. We
published a proposed rule to add the pearl darter (Percina aurora) to
the List of Endangered and Threatened Wildlife in title 50 of the Code
of Federal Regulations (50 CFR 17.11(h)) as threatened on September 21,
2016 (81 FR 64857).
What this document does. This rule will finalize the listing of the
pearl darter as a threatened species.
The basis for our action. Under the Act, we may determine that a
species is an endangered or threatened species based on any of five
factors: (A) The present or threatened destruction, modification, or
curtailment of its habitat or range; (B) overutilization for
commercial, recreational, scientific, or educational purposes; (C)
disease or predation; (D) the inadequacy of
[[Page 43886]]
existing regulatory mechanisms; or (E) other natural or manmade factors
affecting its continued existence. We have determined that water
quality decline from point and nonpoint source pollution continues to
impact portions of this species' habitat. In addition, geomorphology
changes attributed to historical sand and gravel mining operations
within the drainage are considered an ongoing threat. This species has
been extirpated from the Pearl River watershed and is confined today to
the Pascagoula River basin where the species' small population size,
scattered locations, and low genetic (allelic) diversity increase its
vulnerability to extirpation from catastrophic events.
Peer review and public comment. We sought comments from independent
specialists to ensure that our determination was based on
scientifically sound data, assumptions, and analyses. We invited these
peer reviewers to comment on our listing proposal. We also considered
all comments and information received from the public during the
comment period.
Previous Federal Action
Please refer to the September 21, 2016, proposed listing rule (81
FR 64857) for a detailed description of previous Federal actions
concerning this species.
Background
For a more detailed discussion of the taxonomy, biology, status,
and threats affecting the species, please refer to the proposed listing
rule. In the proposed rule, we evaluated the biological status of the
species and factors affecting its continued existence. Our assessment
was based upon the best available scientific and commercial data on the
status of the species, including past, present, and future threats.
Summary of Comments and Recommendations
In the proposed rule, we requested that all interested parties
submit written comments on the proposal by November 21, 2016. We also
contacted appropriate Federal and State agencies, scientific experts
and organizations, and other interested parties and invited them to
comment on the proposal. Newspaper notices inviting general public
comment were published in the Hattiesburg American, Mississippi Press,
and Clarion-Ledger on October 2, 2016. We did not receive any requests
for a public hearing. All substantive information provided during the
comment period has either been incorporated directly into this final
determination or is addressed in the more specific response to comments
below.
Peer Reviewer Comments
In accordance with our peer review policy published on July 1, 1994
(59 FR 34270), we solicited expert opinion from three individuals with
scientific expertise that included familiarity with pearl darter and
its habitat, biological needs, and threats. We received responses from
all three of the peer reviewers.
We reviewed all comments received from the peer reviewers for new
substantive information regarding the listing of the pearl darter. The
peer reviewers generally concurred with our methods and conclusions and
provided additional information, clarifications, and suggestions to
improve the final rule. Where appropriate, we incorporated new
information into the final rule as a result of the peer reviewer
comments, including new survey information. Other substantive peer
reviewer comments are below.
(1) Comment: One peer reviewer suggested our statement that the
species was extirpated from the Pearl River drainage was premature,
since surveys in that system were ongoing, and cautioned that a final
listing decision should be withheld until surveys were completed.
Our Response: While upper Pearl River basin surveys for the pearl
darter were completed in 2011 (Schaefer and Mickle 2011), surveys for
the darter in the lower Pearl River drainage were only completed by the
Mississippi Department of Wildlife, Fisheries, and Parks in May of 2017
(Wagner et al. 2017, entire). Those surveys, which included both
traditional surveys and eDNA analysis (Wagner et al. 2017, p. 5), were
utilized over the last 2 years in an attempt to locate evidence of this
species persisting in the Pearl River system. Our determination that
the pearl darter has not been collected from the Pearl River drainage
in over 40 years, and is considered extirpated from this system, is
validated by these recent survey results.
(2) Comment: One peer reviewer stated that pulp mills should be
considered a threat to water quality degradation. The reviewer also
expressed a suspicion that pulp mill effluent may have had some
influence on extirpation of pearl darters in the Pearl River.
Our Response: We agree and have made changes to this final rule to
reflect the peer reviewer's input in the Summary of Factors Affecting
the Species section, below.
(3) Comment: One peer reviewer stated that increased demand for
water withdrawal by industry and municipalities should be considered an
additional threat to the species in the Pascagoula drainage. The
reviewer stated that this activity will be a continuing threat for all
aquatic resources as coastal populations grow and industrial needs
expand. The commenter cited the 2006 proposed Richton Salt Dome as an
example of water withdrawal posing a threat to the pearl darter.
Our Response: We agree that water withdrawal from the Pascagoula
drainages could have an impact on the ecological health of the system
and potentially impact the pearl darter. However, at this time, we have
no information to indicate that increased demand for water withdrawal
by industry and municipalities currently poses a threat to the pearl
darter, and we note that the peer reviewer did not identify any
specific active projects. The Richton Salt Dome project cited by the
peer reviewer, which at one time was a concern, was terminated and
removed from the Department of Energy's budget in 2011.
(4) Comment: One peer reviewer stated that there was no information
to indicate there has been a decline in pearl darter abundance in the
Bouie River and Black Creek and, particularly, no information
attributing any declines to sedimentation and unstable banks. These
areas have historically had few specimens of darter and have not been
thoroughly surveyed.
Our Response: We agree that there are inadequate data and a lack of
thorough surveying of the Bouie River and Black Creek to definitively
note a decline of the species in those systems, and we have clarified
the rule accordingly. Until recently, there had been no collection
efforts in the Bouie River and Black Creek since 2000. However, in
2016-2017, survey efforts in these systems found pearl darters to be
sparsely present in a few sites (Schaefer in litt. 2017). Evidence of
substantial sedimentation and unstable banks in the Bouie River and
Black Creek has been documented in the past (Mossa and Coley 2004, p.
7; Mississippi Department of Environmental Quality 2005c, p. 16) and
observed currently (Schaefer in litt. 2017). The negative impact of
excessive sedimentation on darter distribution is well known and
addressed under Factor A in the Summary of Factors Affecting the
Species section of the preamble to this rule. Furthermore, there are
also likely other factors contributing to water quality degradation in
these systems,
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such as point and nonpoint source pollution related to stormwater
runoff and effluent discharge from industry, agriculture, and
urbanization; therefore, we have revised our statement regarding
sedimentation.
(5) Comment: One peer reviewer commented that our statement in the
proposed rule on low genetic diversity and restricted gene flow as
reported by Kreiser et al. (2012) ran counter to the hypothesized long-
distance spawning migrations noted elsewhere in the rule. The commenter
stated that the genetic data support a series of potentially disjunct
populations rather than one contiguous population.
Our Response: We appreciate the comment and have clarified in this
final listing rule the statement that pearl darters may have long-
distance spawning migrations (Bart et al. 2001, p. 14). Kreiser's (et
al. 2012, pp. 14-17) recent genetic studies, indicating a series of
potentially disjunct populations, are likely a more accurate
representation of the population structure of the pearl darter (see
Summary of Factors Affecting the Species, Factor E).
Comments From States
The proposed rule was reviewed by the Mississippi Department of
Wildlife, Fisheries and Parks; the Mississippi Forestry Commission; and
the Louisiana Department of Wildlife and Fisheries. The individual
associated with the Mississippi Department of Wildlife, Fisheries and
Parks also served as a peer reviewer, and his comment is addressed in
Comment 1 above. The State agencies generally concurred with our
methods and commented that the literature and data were thorough and
properly documented. They stated that we should withhold our final
listing decision until their surveys in the Pearl River drainage had
been completed. Mississippi Department of Wildlife, Fisheries and Parks
recently provided additional information from their recent site
surveys. The Louisiana Department of Wildlife and Fisheries agreed that
there were no recent records from the Pearl River system despite recent
sampling efforts. An issue raised by the Mississippi Forestry
Commission is addressed below.
(6) Comment: The Mississippi Forestry Commission and two commenters
from the timber industry stated that we mischaracterized the use of
best management practices (BMPs) in Mississippi by stating that: (1)
Their use was confined to lands managed by The Nature Conservancy and
the State of Mississippi, and (2) the lack of a mandatory requirement
makes forestry BMPs less effective. The commenters pointed out that the
forest industry has a number of forest certification programs, such as
the Sustainable Forestry Initiative, which require participating
landowners to meet or exceed State forestry BMPs. The commenters also
stated that silviculture practices implemented with BMPs have minimal
impacts on aquatic species, and that a recent statewide monitoring
survey by Mississippi Forestry Commission indicated that BMPs are being
implemented across all silviculture landscapes in Mississippi
regardless of ownership.
Our Response: We appreciate the additional information provided by
the commenters and commend the timber industry and landowners on their
implementation of BMPs in their timber operations and also the success
of forestry certification programs, such as Sustainable Forestry
Initiative. We have updated information in this rule to acknowledge the
contribution of these forest landowners implementing BMPs in the
Summary of Factors Affecting the Species section, below.
Public Comments
We received five comments from the public, two of which are
addressed in Comment 6, above; the three other commenters simply
expressed their support for the proposed listing.
Summary of Changes From the Proposed Rule
This final rule incorporates minor changes to our proposed rule
based on the comments we received, as discussed above in Summary of
Comments and Recommendations, and newly available survey information.
The survey data allowed us to refine distribution information; thus,
the final total current range of the species is different from that in
the proposed rule. Many small, nonsubstantive changes and corrections
were made throughout the document in response to comments (e.g.,
updating the Background section, threats, minor clarifications).
However, the information we received in response to the proposed rule
did not change our determination that the pearl darter is a threatened
species, nor was it significant enough to warrant reopening the public
comment period. Below is a summary of substantive changes made to the
final rule.
We now estimate the total current range of the pearl
darter in the Pascagoula watershed to be 668 kilometers (km) (415 miles
(mi)) based on a reanalysis of collection records and recent survey
results. Detailed information about the species' range within each of
the seven river/creek systems is presented in the preamble of this
rule, under Current Distribution.
Additional information on habitat and population structure
from peer reviewers and recent studies (Wagner et al. 2017) has been
added to the preamble.
Additional information and suggestions from peer reviewers
was added to clarify and improve the accuracy of the information in the
Distribution, Habitat, Biology, and Threats sections of the preamble to
the proposed rule.
Additional information on the species' abundance and
probable cause of decline in the Pearl River, as related to the
potential threat to existing populations in the Pascagoula system, from
two peer reviewers was added into the Summary of Factors Affecting the
Species section of this rule, below.
Additional narrative on historical threats within the
Pearl River basin, as well as additional historical and current threats
affecting water quality within the Pascagoula River basin, including
increased brine concentration from oil and gas production and pulp mill
effluent related to pulp, paper, and lumber mills, was added to the
preamble.
Summary of Biological Status
Below we present a summary of the biological and distributional
information discussed in the proposed listing rule (81 FR 64857;
September 21, 2016). We also present new information published or
obtained since the proposed rule was published (see Summary of Changes
from the Proposed Rule, above).
Taxonomy and Species Description
The pearl darter (Percina aurora) is a small fish and is one of
three members of the subgenus Cottogaster (Ross 2001, p. 500). The
species is allied to the channel darter (P. copelandi) (Ross et al.
1989, p. 25) but is distinguished from it by its larger size, lack of
tubercules (small, raised, skin structures), heavy pigmentation, number
of marginal spines on belly scales of breeding males, and fully scaled
cheeks (Suttkus et al. 1994, pp. 13-14). Generally, pearl darters range
in size from 22 to 59 millimeters (mm) (0.87 to 2.3 inches (in)) in
length with the majority of adults being from 30 to 41 mm (1.2 to 1.6
in) long (Clark and Schaefer 2015, p. 10).
Historical Distribution
The pearl darter is historically known from localized sites within
the Pearl and Pascagoula River drainages in
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Mississippi and Louisiana, based on collection records from 16 counties
and parishes of Mississippi and Louisiana. Examination of site records
of museum fish collections from the Pearl River drainage (compiled from
Suttkus et al. 1994, pp. 15-18) suggests that the pearl darter once
inhabited the large tributaries and main channel habitats within these
drainages from St. Tammany Parish, Louisiana, to Simpson County,
Mississippi. This area totaled approximately 708 km (440 mi) within the
Pearl River basin and included the lower Pearl River, the Strong River,
and the Bogue Chitto River (compiled from MMNS 2016, unpublished data;
Slack et al. 2005, pp. 5-10; Ross 2001, p. 499; Ross et al. 2000, pp.
2-5; Bart and Piller 1997, pp. 3-10; Bart and Suttkus 1996, pp. 3-4;
Suttkus et al. 1994, pp. 15-18). However, there have been no records of
this species from the Pearl River drainage in over 40 years, despite
repeated collecting efforts through the years (Wagner et al. 2017, pp.
3-10, 12; Geheber and Piller 2012, pp. 633-636; Schaefer and Mickel
2011, p. 10; Slack et al. 2005, pp. 5-10; Tipton et al. 2004, pp. 56-
57; Ross 2001, p. 499; Bart and Piller 1997, p. 1; Bart and Suttkus
1996, pp. 3-4; Bart and Suttkus 1995, pp. 13-14; Suttkus et al. 1994,
pp. 15-18). Survey efforts over the last few years at all historical
sites, including north of and just below the Ross Barnett Reservoir
(Schaefer and Mickle 2011, pp. 8-10), have confirmed its absence from
the Pearl River system (Wagner et al. 2017, pp. 3-4; Roberts in litt.
2015; Geheber and Piller 2012, p. 633), including the recent analysis
of water samples for eDNA from the Pearl River proper, Strong River,
and Bogue Chitto River (Piller in litt. 2017). Thus, the pearl darter
is considered extirpated from the Pearl River system today.
Current Distribution
Today, the pearl darter occurs in scattered sites within an
approximately 668-km (415-mi) area of the Pascagoula drainage,
including the Pascagoula (101 km, 63 mi), Chickasawhay (257 km, 160
mi), Leaf (186 km, 115 mi), Chunky (31 km, 19 mi), and Bouie (24 km, 15
mi) Rivers and Okatoma (37 km, 23 mi) and Black Creeks (32 km, 20 mi)
(Wagner et al. 2017, pp. 3-10, 12; Wagner in litt. 2017; Clark and
Schaefer 2015, pp. 10, 19, 23; Schaefer and Mickle 2011, pp. 1-3; Slack
et al. 2002, p. 9).
The average catch at known occupied sites, using standard sampling
(30 minutes with heavy leaded seine) is 2.1 individuals (Wagner et al.
2017. pp. 3-4; Clark and Schaefer 2015, pp. 9-14, 18-22), indicating a
species that is rare. Surveys by Kreiser et al. (2012, pp. 29-32) found
sporadic occurrences of the species within the Pascagoula River from
its headwaters at the confluence of the Leaf and Chickasawhay Rivers
downstream to where the river bifurcates (splits). Recent survey
efforts indicate reproducing populations in the Chickasawhay and Leaf
Rivers, based on the presence of different size classes (Clark in litt.
2017; Wagner in litt. 2017; Wagner et al. 2017, p. 3; Schaefer in litt.
2017; Clark and Schaefer 2015, pp. 9-14, 18-22). Though there is a
clear pattern of higher abundance and greater rate of occurrence at
sites in the Chickasawhay River (5.03 0.62 pearl darters
per hour) compared to the Leaf River (2.18 0.56 pearl
darters per hour); a pattern that has remained constant over time
(Clark and Schaefer 2015, pp. 9-14). Surveys in 2016 of historical
locations (Clark in litt. 2017; Schaefer in litt. 2017) in the Bouie
River, Okatoma Creek, and Black Creek yielded seven fish in the Okatoma
Creek and one specimen each in the Bouie River and Black Creek. In
2017, one pearl darter was collected in the Chunky River, confirming
its presence in that system for the first time since its last
collection there over 15 years ago.
Habitat and Biology
The pearl darter occurs in low-gradient, coastal plain rivers and
creeks (Suttkus et al. 1994, p. 13), predominately classified as 4th to
2nd order streams (Strahler stream order hierarchy). There have been no
comprehensive microhabitat studies on the pearl darter; however, based
on observations of occupancy in the field, microhabitat features
consist of a bottom substrate mixture of sand, silt, loose clay,
gravel, organic material, and snags (Slack et al. 2005, pp. 9-11). The
species has been collected at the steep ends of sandbars, and inside
river bends where material is deposited. The water where the species is
typically captured has a slow to medium current velocity (0.003 to
0.635 centimeters/second (cm/s) (0.53 to 0.25 in/s) (tabulated from
Clark in litt. 2017, Slack in litt. 2017, Schaefer in litt. 2017,
unpublished data; Slack et al. 2005, p. 10). In fact, based on cluster
analysis and ordination of habitat data of the Leaf and Chickasawhay
Rivers, higher densities of pearl darters were found in slower moving,
deeper waters with finer substrate (Clark and Schaefer 2015, p. 11).
There is very little aquatic vegetation in these drainages (Slack et
al. 2005, p. 9), and vegetation that may be present is usually river
weed (Podostemum ceratophyllum) attached to rocks (Drennen and Wagner
2017, pers. observ.). Banksides where the pearl darter was collected
are vegetative and not vertical or severely eroded (Schaefer in litt.
2017, unpublished data).
There is no specific information available on the diet of the pearl
darter. However, the channel darter (P. copelendi), a closely allied
species in similar habitat, has been reported to feed on chironomid
flies, small crustaceans, mayflies, and caddisflies (Kuehne and Barbour
1983, p. 49).
Summary of Factors Affecting the Species
Below we present a summary of the threats information from the
proposed listing rule. We also present new information published or
obtained since the proposed rule was published, including information
received during the public comment period.
Factor A: The Present or Threatened Destruction, Modification, or
Curtailment of Its Habitat or Range
Members of the Cottogaster subgenus have undergone range
contractions that are of potential conservation concern throughout
their respective distributions (Dugo et al. 2008, p. 3; Warren et al.
2000, pp. 7-8; Goodchild 1994, pp. 433-435). The pearl darter was
extirpated from the Pearl River drainage, perhaps as early as the
1970s, and many of the stressors thought to have played a role in its
loss in that system are present in the Pascagoula River drainages where
the species occurs today, including impoundments (sills and dams);
instability in the channel; increased sedimentation from the removal of
riparian vegetation and poor agriculture and silviculture practices;
and general chronic water degradation from point and non-point source
pollution (Piller et al. 2004, pp. 1004-1011; TNC 2004, p. 5; Ross
2001, pp. 499-500).
Water Quality Degradation
Water quality degradation, particularly non-point source pollution
from incompatible commercial and industrial development and land use
practices, has been a major concern within the Pearl River basin (TNC
2004, p. 18). Similarly, the Pascagoula River system suffers from acute
and localized water quality degradation by nonpoint source pollution in
association with surface, stormwater, and effluent runoffs from
urbanization and municipal areas (MDEQ 2005c, p. 23; 2005d, p. 16).
``Total Maximum Daily Loads'' (TMDLs), a term in the U.S. Clean Water
Act describing a benchmark set for a certain pollutant to bring water
quality up to the applicable standard, have been established for 89
segments of the Pascagoula River basin, many of which
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include portions of the pearl darter's range (MDEQ 2014a, pp. 18-21).
For sediment, one of the most pervasive pollutants, the State of
Mississippi has TMDLs for various tributaries and main stems of the
Leaf and Chickasawhay Rivers. To date, efforts by the State of
Mississippi to improve water quality in the Pascagoula River basin to
meet these TMDL benchmarks have been inadequate (MDEQ 2014a, pp. 18-
21). Thirty-nine percent of the Pascagoula River basin tributaries are
rated fair or poor due to pollution impacts (MDEQ 2014a, pp. 18-21;
MDEQ 2008, p. 17).
Most water quality threats are due to increased sediment loads and
variations in pH (MDEQ 2014a, pp. 1-51; 2008a, pp. 13-15). Sediment in
stormwater runoff increases water turbidity and temperature and
originates locally from poorly maintained construction sites, timber
harvest tracts, agricultural fields, clearing of riparian vegetation,
and gravel extraction in the river floodplain. Suttkus et al. (1994, p.
19) attributed the loss of the pearl darter in the Pearl River to
increasing sedimentation from habitat modification caused by the
removal of riparian vegetation and extensive cultivation near the
river's edge. Excessive sediments disrupt feeding and spawning of fish
and aquatic insects, abrade and suffocate periphyton (mixture of algae,
bacteria, microbes, and detritus that is attached to submerged
surfaces), and impact fish growth, survival, and reproduction (Waters
1995, pp. 55-62). A localized portion of the Chickasawhay River is on
the State Section 303(d) List of Water Bodies as impaired due to
sediment (MDEQ 2005b, p. 17).
Nonpoint source pollution is a localized threat to the pearl darter
within the drainage, and is more prevalent in areas where certified
best management practices (BMPs) are not utilized. The use of certified
BMPs during land-altering activities can greatly reduce impacts to
water quality. Certified BMPs, currently implemented by the forestry
industry (e.g., Sustainable Forestry Initiative, Forest Stewardship
Council, and American Tree Farm System), are helping to minimize or
eliminate non-point source pollution during the course of forestry
activities. The Mississippi Forestry Commission (2016, entire) reports
certified BMP implementation rates to be high in Mississippi for
forestry activities, primarily due to the efforts of State forestry
agencies and forest certification programs (Schilling and Wigley 2015,
pp. 3-7).
Historically, timber harvesting and processing was extensive in the
Pearl River basin, and at one time, the basin was home to one of the
most important lumber centers in the United States (Thigpen 1965, pp.
66-69). Pulp and paper manufacturing began in the Pascagoula watershed
in Mississippi with three major mills (Monthly Review 1958, p. 83).
Today, there are six major pulp mills in the Pascagoula River basin
whose effluent may be a threat to the pearl darter. Paper mill effluent
is a contributor to water quality degradation and is suspected to have
had some influence on the extirpation of the pearl darter in the Pearl
River system (Slack in litt. 2016). Fish and mussel kills were
reportedly not uncommon within reaches downstream from pulp mills in
Lawrence County near historical locations for the pearl darter (Slack
in litt. 2016). As recently as 2011, a ``black liquor'' (wastewater)
spill from a paper manufacturing process resulted in a massive fish
kill in the Pearl River (Kizha et al. 2016, pp. 926-929; Piller and
Geheber 2015, pp. 2433-2434).
Numerous studies have documented the effects of pulp and paper mill
effluents on fish populations (Beyer et al. 1996, pp. 212-224).
Depending on the bleaching process, pulp- and paper mill effluents may
contain various kinds and concentrations of chlorinated organic
compounds such as polychlorinated dibenzodioxins (dioxins) and
polychlorinated dibenzofurans (furans), which elicit several lethal and
sublethal effects in fish, such as alterations in steroid biosynthesis
(manufacturing of hormones and other organic compounds), gonadal (sex
gland) development, sexual maturation, and expression of secondary sex
characteristics (features that appear at maturity such as coloration).
These types of compounds are known to bioaccumulate and have
reproductive and antiestrogen (opposite effects of hormones) impacts on
fish (Hoffman et al. 2003, pp. 1063-1065).
Additionally, some contaminants may bind with one another (i.e.,
heavy metals bind with sediments or other contaminants in the water
column) within the Pascagoula River drainage. These bound chemical
contaminants have not been addressed in TMDLs. Only seven TMDLs for
metals have been completed (MDEQ 2008, pp. 1-55). The Davis Dead River,
a tributary at the most downstream site of the pearl darter's range, is
considered critically impaired by mercury (MDEQ 2011, pp. 1-29), and
fish consumption advisories continue for mercury in certain gamefish
species in the Pascagoula River main stem (MDEQ 2008, p. 43).
There are 15 permitted point source discharge sites within the
Bouie River system (MDEQ 2005a, p. 6) and an unknown amount of nonpoint
runoff sites. Municipal and industrial discharges during periods of low
flow (i.e., no or few rain events) intensify water quality degradation
by increasing water temperatures, lowering dissolved oxygen, and
changing pH. Within the Pascagoula River basin, pollutants causing
specific channel or river reach impairment (i.e., those pollutants
preventing the water body from reaching its applicable water quality
standard (Environmental Protection Agency 2012, pp. 1-9)), include
sedimentation; chemicals and nutrients in the water column; and various
toxins, such as heavy metals like lead or cadmium for a total of 304 km
(189 mi) impaired riverine segments. TMDLs were completed for
pesticides such as dichlorodiphenyltrichloroethane (DDT), toxaphene,
dioxin, and pentachlorophenol, although much of the data and results
are not finalized and remain unavailable for the designated reaches
(Environmental Protection Agency 2012, pp. 1-7; MDEQ 2003, pp. 5-10;
Justus et al. 1999, p. 1).
Localized wastewater effluent into the Leaf River from the City of
Hattiesburg is negatively impacting water quality (Hattiesburg American
2015, pp. 1-2; Mississippi River Collaboration 2014, p. 1). Existing
housing, recreational cabins, and trailers along the banks of the Leaf
River between I-59 and the town of Estabutchie cause nutrient loading
through treated sewage and septic water effluent (Mississippi River
Collaboration 2014, p. 1). In 1997, Bart and Piller (p. 12) noted
extensive algal growth during warmer months in the Leaf and Bouie
Rivers, indicating nutrient and organic enrichment and decreases in
dissolved oxygen and pH changes. Today, at specific locations, the
water quality of the Bouie and Leaf Rivers and their tributaries
continues to be negatively impacted by sediment, organic enrichment,
low dissolved oxygen, fecal coliform, and elevated nutrients (MDEQ
2016, p. 86, 91; 2014a, p. 18, 21, 32; 2005a, pp. 1-26; 2004, pp. 1-
29).
Oil and Gas Development
Nonpoint and point source pollution from oil and gas exploration,
including drill field construction, active drilling, and pipeline
easements, may add localized pollutants into the Pascagoula River basin
during stormwater runoff events if BMPs are not used. There is one
major oil refinery within the basin along with 6 oil pumping stations,
10 major crude pipelines, 4 major product oil pipelines, and 5 major
gas and more than 25 lesser gas lines stretching hundreds of miles and
crisscrossing the
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main stem Pascagoula, Bouie, Leaf, Chickasawhay, and Chunky Rivers and
their tributaries; in addition, there are more than 100 active oil
producing wells within the pearl darters' watersheds (compiled from Oil
and Gas Map of Mississippi in Phillips 2013, pp. 10, 23). All have the
potential to rupture or leak and cause environmental and organismal
damage as evidenced by the Genesis Oil Company and Leaf River oil spill
of 2000 (Environmental Science Services, Inc. 2000, pp. 1-50; Kemp
Associates, PA, 2000, pp. 4-5; The Clarion-Ledger, December 23, 1999,
p. 1B) and Genesis Oil Company spill in Okatoma Creek in February 2016
(Drennen 2016, pers. observ.). In addition to gas pipelines, there are
numerous railways that cross pearl darter habitat that are subject to
accidental and catastrophic spilling of toxins such as fuel oil,
methanol, resin, and fertilizer (MDEQ 2014b, pp. 1-23).
Alternative oil and gas collection methods (i.e., hydraulic
fracturing (``fracking'') and horizontal drilling and injection) have
allowed the expansion of oil and gas drilling into deposits that were
previously inaccessible (Phillips 2013, p. 21), which has led to
increased activity within southern Mississippi, including portions of
the Pascagoula River basin. There are more than 100 water injection
disposal wells and enhanced oil recovery wells within the basin
(compiled from Active Injection Well Map of Mississippi in Phillips
2013, p. 49). A variety of chemicals (e.g., 15% diluted hydrochloric
acid, surfactants, potassium chloride) are used during the drilling and
fracking process (Colborn et al. 2011, pp. 1040-1042), and their wastes
are stored in open pits (retention basins) or storage facilities.
Spills during transport or releases due to retention basin failure or
overflow pose a risk for surface and groundwater contamination, which
can cause significant adverse effects to water quality and aquatic
organisms that inhabit these watersheds (Osborn et al. 2011, pp. 8172-
8176; Kargbo et al. 2010, pp. 5680-5681; Wiseman 2009, pp. 127-142). In
addition, contamination of streams with brine (chloride), a byproduct
of oil and gas development, poses a significant risk to aquatic
habitats and species. High chloride concentrations interfere with
osmoregulation (maintenance of proper levels of salts and other solutes
in bodily fluids) and hinder the organism's survival, growth, and
reproduction (Hunt et al. 2012, p. 1). Brine contamination has been
documented within the pearl darter's historical range in the Pearl
River system (Kalhoff 1993, pp. 12-15, 19-20, 25; Kalhoff 1986, p. 49)
and within the Pascagoula River basin where it currently occurs,
including several Leaf and Chickasawhay River drainage basin
tributaries (Kalhoff 1986, pp. 52-63). There is currently no routine
water quality monitoring in areas where the pearl darter currently
occurs, so it is unlikely that the effects of a leak or spill would be
detected quickly enough to allow for a timely response.
Geomorphology Changes
Piller et al. (2004, pp. 1004-1011) cited numerous human-caused
disturbances within the Pearl River since the 1950s, including
channelization, reservoir construction, and channel modification from
bank collapse downstream of dams. Specifically, the Pearl River
Navigation Canal in 1956, the Ross Barnett Reservoir in 1964, and
channel changes of the lower Pearl River (increased width and decreased
depth) were implicated in the decline of abundance for several fish
species in that system (Piller et al. 2004, pp. 1004-1011). These
habitat modifications and channel changes resulted in the loss of
gravel substrates in places, completely replacing gravel bars with sand
or sediment, which are not appropriate substrate for the pearl darter
and other species (Tipton et al. 2004, pp. 58-60; TNC 2004, p. 5).
Tipton et al. (2004, pp. 58-60) documented a decrease in fish diversity
and abundance within the disturbed reaches as compared with relatively
undisturbed reaches. These changes most likely contributed to the
decline of the pearl darter in the Pearl River system and potentially
threaten the species in the Pascagoula system.
Pearl darters are not found in impounded waters and are intolerant
of lentic (standing water) habitats that may be formed by gravel mining
or other landscape-altering practices. Incompatible sand and gravel
mining and its disruption of topography, vegetation, and flow pattern
of streams is considered a major stressor to the Pearl River system
where the pearl darter once occurred (TNC 2004, p. 16). In the species'
current range in the Pascagoula system, the results of historical sand
and gravel dredging impacts have been a concern for the Bouie and Leaf
Rivers (MDEQ 2000, pp. 1-98). Historically, the American Sand and
Gravel Company (1995, p. B4) has mined sand and gravel using a
hydraulic suction dredge, operating within the banks or adjacent to the
Bouie and Leaf Rivers. Large gravel bars of the river and its
floodplain have been removed over the past 50 years, creating open-
water areas that function as deep lake systems (American Sand and
Gravel Company 1995, pp. B4-B8). The creation of these large, open-
water areas has accelerated geomorphic processes, specifically
headcutting (erosional feature causing an abrupt drop in the streambed)
that has adversely affected the flora and fauna of many coastal plain
streams (Patrick et al. 1993, p. 90). Mining in active river channels
typically results in incision upstream of the mine by knickpoints
(breaks in the slope of a river or stream profile caused by renewed
erosion attributed to a bottom disturbance that may retreat upstream),
sediment deposition downstream, and an alteration in channel morphology
that can have impacts for years (Mossa and Coley 2004, pp. 1-20). The
upstream migration of knickpoints, or headcutting, may cause
undermining of structures, lowering of alluvial water tables (aquifer
comprising unconsolidated materials deposited by water and typically
adjacent to rivers), channel destabilization and widening, and loss of
aquatic and riparian habitat. This geomorphic change may cause the
extirpation of riparian and lotic (flowing water) species (Patrick et
al. 1993, p. 96).
Sedimentation from unstable banks and loose, unconsolidated
streambeds (Bart and Piller 1997, p. 12) is likely impacting the pearl
darters in the Bouie River and Black Creek. Mossa and Coley (2004, p.
17) determined that, of the major tributaries in the Pascagoula basin,
the Bouie River was the least stable. Channel enlargement of the Bouie
River showed higher than background values associated with avulsions
(the rapid abandonment of a river channel and the formation of a new
river channel) into floodplain pits and increased sedimentation. In
addition, channel enlargement of 400 to 500 percent in the Bouie River
has occurred at specific sites due to instream gravel mining (Mossa et
al. 2006, entire; Mossa and Coley 2004, p. 17). Ayers (2014, pp. 43-45)
also found significant and lengthy instream channel form changes in the
Chickasawhay River floodplain. Clark and Schaefer (2015, pp. 13-14)
noted a slight decrease in fish species richness in the upper
Pascagoula River basin from their 2004 sampling, which they attributed
to past anthropogenic influences such as gravel mining, bankside
practices, and construction.
In the Bogue Chitto River of the Pearl River basin, Stewart et al.
(2005, pp. 268-270) found that the assemblages of fishes had shifted
over 27 years. In this time period, the sedimentation rates
[[Page 43891]]
within the system had increased dramatically and caused the decrease in
the relative abundance of all fish in the family Percidae (Stewart et
al. 2005, pp. 268-270) from 35 percent to 9 percent, including the
extirpation of pearl darters. Ross et al. (1992, pp. 8-9) studied
threats to the Okatoma Creek (Pascagoula basin) fish diversity and
predicted that geomorphic changes to the stream would reduce the fish
habitat diversity resulting in a decline of the fish assemblages,
including the pearl darter.
Impoundments
Dams and other flow control structures within a river can block
fish passage, disrupt the natural flow patterns, and cause channel
degradation and erosion (see ``Geomorphology Changes'' section above)
that directly impact aquatic life habitat, as well as reduce the
capacity of the stream to carry water (TNC 2004, p. 17). Streams with
highly altered flow regimes often become wide, shallow, and
homogeneous, resulting in poor habitat for many fish species (Bunn and
Arthington 2002, pp. 493-498). The decline of the pearl darter in the
Pearl River was noted after the construction of low sill dams. Bart (in
TNC 2004, p. 5) speculated that, after spawning, young darters in the
Pearl River were swept downriver and unable to migrate back upriver due
to the low water sills and varied water flow; their limited success
year after year likely caused the population to crash. These low sill
dams are also thought to have led to the extirpation of the Alabama
shad (Alosa alabamae) from that system (Mickel et al. 2010, p. 158).
The proposed damming of Little and Big Cedar Creeks, tributaries to
the Pascagoula River, for establishment of two recreational lakes
(George County Lakes) (U.S. Army Corps of Engineers 2015, pp. 1-13) has
prompted the American Rivers organization to recently list the
Pascagoula River as the 10th most endangered river in the country
(American Rivers 2016, pp. 20-21). Though the proposed project is not
directly within known pearl darter habitat, the lakes may decrease
water quantity entering the lower Pascagoula basin and will likely
concentrate pollutants, reduce water flow, and alter downstream food
webs and aquatic productivity (Poff and Hart 2002, p. 660).
Summary of Factor A
Habitat modification and resultant water quality degradation are
occurring within the pearl darter's current range and likely led to the
loss of the species from the Pearl River drainage. Water quality
degradation occurs locally from point and nonpoint source pollution in
association with land surface, stormwater, and effluent runoff from
urbanization, industry, and municipal areas. Of particular concern is
the threat of overflooding of storage ponds for industrial effluent,
such as that from pulp and paper manufacturing. Increased sediment from
a variety of sources, including geomorphological changes and bank
instability from past habitat modification, appears to be the major
contributor to water quality declines in this species' habitat.
Localized sewage and waste water effluent also pose a threat to this
species and its habitat. The pearl darter's vulnerability to
catastrophic events, particularly the release of pollutants in its
habitat from oil spills, train derailments, and hydraulic fracturing,
is also a concern due to the abundance of oil wells, pumping stations,
gas lines, and railways throughout its habitat, and the increased
interest in alternative oil and gas collection methods in the area. The
proposed damming of Big and Little Cypress Creeks may decrease water
flow and increase nutrient concentration into the Pascagoula River.
These threats continue to impact water quality and habitat conditions
through much of this species' current range. Therefore, we conclude
that habitat degradation is presently a moderate threat to the pearl
darter that is expected to continue and possibly increase into the
future.
Factor B: Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
The pearl darter is not a commercially valuable species, and
collecting is not considered a factor in its decline. Therefore, we do
not consider overutilization for commercial, recreational, scientific,
or educational purposes to be a threat to the pearl darter at this
time.
Factor C: Disease or Predation
We have no specific information indicating that disease or
predation is negatively impacting pearl darter populations. Therefore,
we do not consider these factors to be threats to the pearl darter at
this time.
Factor D: The Inadequacy of Existing Regulatory Mechanisms
The State of Mississippi classifies the pearl darter as endangered
(Mississippi Natural Heritage Program 2015, p. 2), and prohibits the
collection of the pearl darter for scientific purposes without a State-
issued collecting permit. However, as discussed under Factor B, we have
no evidence to suggest that scientific collection poses a threat to
this species. This State classification conveys no legal protection for
the pearl darter's habitat nor does it prohibit habitat degradation,
which is the primary threat to the species. The pearl darter receives
no protection in Louisiana, where it is considered to have historically
occurred (Louisiana Department of Wildlife and Fisheries 2005, p. 39).
The pearl darter and its habitats are afforded some protection from
water quality and habitat degradation under the Clean Water Act of 1972
(33 U.S.C. 1251 et seq.) and the Mississippi Water Pollution Control
Law, as amended, 1993 (Code of Mississippi, section 49-17-1, et seq.)
and regulations promulgated thereunder by the Mississippi Commission on
Environmental Quality. Although these laws have resulted in some
enhancement in water quality and habitat for aquatic life, particularly
in reducing point-source pollutants, they have been inadequate in fully
protecting the pearl darter from sedimentation and other nonpoint
source pollutants.
The State of Mississippi maintains water-use classifications
through issuance of National Pollutant Discharge Elimination System
permits to industries, municipalities, and others that set maximum
limits on certain pollutants or pollutant parameters. For water bodies
on the Clean Water Act section 303(d) list of impaired streams, the
State is required to establish a TMDL for the pollutants of concern
that will improve water quality to the applicable standard. The
establishment of TMDLs for 89 river or stream segments and ratings of
fair to poor for 39 percent of the tributaries within the Pascagoula
basin are indicative of water pollution impacts within the pearl
darter's habitat (MDEQ 2008a, p. 17). TMDLs are not an enforced
regulation, and only reflect benchmarks for improving water quality;
they have not been successful in reducing water quality degradation
within this species' habitat, as these streams continue to remain on
the 303(d) list of impaired streams.
Mississippi Surface Mining and Reclamation Law, Miss. Code Ann.
section 53-7-1 et seq., and Federal laws regarding oil and gas drilling
(42 U.S.C. 6921) are generally designed to protect freshwater resources
like the pearl darter, but these regulatory mechanisms do not contain
specific provisions requiring an analysis of project impacts to fish
and wildlife resources. They also do not contain or provide for any
formal mechanism requiring coordination with, or input from, the
Service or the
[[Page 43892]]
Mississippi Department of Wildlife, Fisheries and Parks regarding the
presence of federally endangered, threatened, or candidate species, or
other rare and sensitive species. In the case of surface mining,
penalties may be assessed if damage is serious, but there is no
immediate response for remediation of habitats or species. As
demonstrated under Factor A, periodic declines in water quality and
degradation of habitat for this species are ongoing despite these
protective regulations. These mechanisms have been inadequate to
protect the species from sediment runoff and turbidity within its
habitat associated with land surface runoff and municipal and
industrial discharges, as described under Factor A. There are currently
no requirements within the scope of other statewide environmental laws
to specifically consider the pearl darter or ensure that a project will
not significantly impact the species.
The pearl darter likely receives ancillary protection (i.e., water
quality improvements, protection from geomorphological changes) where
it co-occurs with two other federally listed species, the Gulf sturgeon
(Acipenser oxyrhynchus desotoi) and yellow-blotched map turtle
(Graptemys flavimaculata), during the course of consultation on these
species under section 7 of the Act. However, protective measures
through section 7 of the Act would be triggered only for those projects
having a Federal nexus, which would not include many of the water
quality disturbances caused by industry, municipalities, agriculture,
or private landowners.
Additional protection of 53,520 hectares (ha) (132,128 acres (ac))
within the Pascagoula basin watershed occurs due to the Mississippi
Wildlife, Fisheries and Parks' management of six Wildlife Management
Areas (WMAs) within the upper drainage basin for recreational hunting
and fishing. Four of the six WMAs (Chickasawhay and Leaf Rivers, Mason
and Red Creeks) do not directly border the river system, but they do
contain and protect parcels of upland buffer, wetland, and tributaries
to the basin. The Pascagoula River and Ward Bayou WMAs (20,329 ha;
50,234 ac) consist of wetland buffer and river/stream reach protecting
approximately 106 km (66 mi) of the Pascagoula River main stem (Stowe
in litt. 2015). The Nature Conservancy (TNC) protects 14,164 ha (35,000
ac) within the Pascagoula River watershed and approximately 10 km (6
mi) of the Pascagoula River shoreline in Jackson County, Mississippi.
Of that amount, the Charles M. Deaton Nature Preserve (1,336 ha, 3,300
ac) protects the upper reaches of the Pascagoula River, where the Leaf
and Chickasawhay Rivers converge, and is part of a 19,020-ha (47,000-
ac) swath of public lands surrounding the Pascagoula River, which
includes approximately 8 km (5 mi) of the Chickasawhay River and
approximately 7 km (4 mi) of the Leaf River shorelines (Stowe in litt.
2015).
These State-managed WMAs and TNC preserves provide a measure of
protection for approximately 134 km (84 mi) or 30 percent of the river
reaches within this species' current range. Point and nonpoint sediment
sources are decreased or reduced by using and monitoring certified BMPs
during silviculture, road maintenance, and other landscape-altering
activities. However, only short segments of shoreline in the
Chickasawhay and Leaf Rivers are within these WMAs. Remaining lands
within these segments can be vulnerable to farming and timbering to the
bankside edge, and construction of structures such as houses, septic
facilities, dams, and ponds. Each land management action can increase
stormwater runoff laden with sediment and agricultural and wastewater
chemicals. The impact of silvicultural activities on water quality
degradation are likely lower than other land-altering activities
according to information in the Mississippi Forestry Commission's
report (2016, entire) that found certified BMP implementation rates to
be high across all silvicultural landscapes in Mississippi.
Summary of Factor D
Despite existing authorities such as the Clean Water Act,
pollutants continue to impair the water quality throughout much of the
current range of the pearl darter. State and Federal regulatory
mechanisms have helped reduce the negative effects of point source and
nonpoint source discharges, yet these regulations are difficult to
implement, and may not provide adequate protection for sensitive
species like the pearl darter. Thus, we conclude that existing
regulatory mechanisms do not adequately protect the pearl darter from
the impact of other threats.
Factor E: Other Natural or Manmade Factors Affecting Its Continued
Existence
Small Population Size and Loss of Genetic Diversity
The pearl darter has always been considered rare (Deacon et al.
1979, p. 42) and is currently restricted to localized sites within the
Pascagoula River drainage. Genetic diversity has likely declined due to
fragmentation and separation of reproducing pearl darter populations.
Kreiser et al. (2012, pp. 12-17) found that disjunct populations of
pearl darters within the Leaf and Chickasawhay Rivers showed some
distinct alleles suggesting that gene flow between the two rivers was
restricted and perhaps that the total gene pool diversity was
declining. Collecting data (Ross 2001, p. 500; Bart and Piller 1997, p.
4; Bart and Suttkus 1996, p. 4; Suttkus et al. 1994, p. 19) indicate
that the pearl darter is rare in the Pascagoula River system, as when
this species is collected it is typically in low numbers and a
disproportionately low percentage of the total fish collected (catch
per unit effort of 2.1 individuals per site, Clark and Shaefer 2015, p.
4).
Species that are restricted in range and population size are more
likely to suffer loss of genetic diversity due to genetic drift,
potentially increasing their susceptibility to inbreeding depression,
decreasing their ability to adapt to environmental changes, and
reducing the fitness of individuals (Allendorf and Luikart 2007, pp.
117-146; Soul[eacute] 1980, pp. 157-158). It is likely that some of the
pearl darter populations are below the effective population size
required to maintain long-term genetic and population viability
(Soul[eacute] 1980, pp. 162-164).
The long-term viability of a species is founded on the conservation
of numerous local populations throughout its geographic range (Harris
1984, pp. 93-104). The presence of viable, separate populations is
essential for a species to recover and adapt to environmental change
(Noss and Cooperrider 1994, pp. 264-297; Harris 1984, pp. 93-104).
Inbreeding and loss of neutral genetic variation associated with small
population size reduces the fitness of the population (Reed and
Frankham 2003, pp. 230-237) and accelerates population decline (Fagan
and Holmes 2006, pp. 51-60). The species' small numbers within
scattered locations, coupled with its lack of genetic variability, may
decrease the species' ability to adapt or recover from major
hydrological events that impact potential spawning habitat (Clark and
Schaefer 2015, pp. 18-22).
Hurricanes
Fish and aquatic communities and habitat, including that of the
pearl darter, may be changed by hurricanes (Schaefer et al. 2006, pp.
62-68). In 2005, Hurricane Katrina destroyed much of the urban and
industrial areas along the lower Pascagoula River basin and also
impacted the ecology upriver to the confluence with the Leaf and
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Chickasawhay Rivers. Many toxic chemicals that leaked from grounded and
displaced boats and ships, storage facilities, vehicles, septic
systems, business sites, and other sources due to the hurricane were
reported in the rivers, along with saltwater intrusion from the Gulf of
Mexico. Initial assessment identified several fish kills and increased
surge of organic material into the waters, which lowered dissolved
oxygen levels (Schaefer et al. 2006, pp. 62-68). As discussed below,
the deleterious impacts of climate change will likely lead to an
increase in the strength and frequency of hurricanes.
Climate Change
Numerous long-term climate changes have been observed including
widespread changes in precipitation amounts, ocean salinity, wind
patterns, and aspects of extreme weather including droughts, heavy
precipitation, heat waves, and the intensity of tropical cyclones
(Intergovernmental Panel on Climate Change 2014, p. 4). Climate change,
and the resultant shifts in spatial distribution, may result in
increased fragmentation which would increase the vulnerability of any
isolated populations to future extinction (Comet et al. 2013, p. 635).
However, while continued change is certain, the magnitude and rate of
change is unknown in many cases.
Climate change has the potential to increase the vulnerability of
the pearl darter to random catastrophic events (Thomas et al. 2004, pp.
145-148; McLaughlin et al. 2002, pp. 6060-6074). An increase in both
severity and variation in climate patterns is expected, with extreme
floods, strong storms, and droughts becoming more common
(Intergovernmental Panel on Climate Change 2014, pp. 58-83). Thomas et
al. (2004, pp. 145-148) report that frequency, duration, and intensity
of droughts are likely to increase in the Southeast as a result of
global climate change. Kaushal et al. (2010, p. 465) reported that
stream temperatures in the Southeast have increased roughly 0.2-0.4
[deg]C (0.3-0.7[emsp14][deg]F) per decade over the past 30 years, and
as air temperature is a strong predictor of water temperature, stream
temperatures are expected to continue to rise. Predicted impacts of
climate change on fishes, related to drought, include disruption to
their physiology (e.g., temperature tolerance, dissolved oxygen needs,
and metabolic rates), life history (e.g., timing of reproduction,
growth rate), and distribution (e.g., range shifts, migration of new
predators) (Comte et al. 2013, pp. 627-636; Strayer and Dudgeon 2010,
pp. 350-351; Heino et al. 2009, pp. 41-51; Jackson and Mandrak 2002,
pp. 89-98). However, estimates of the effects of climate change using
available climate models typically lack the geographic precision needed
to predict the magnitude of effects at a scale small enough to
discretely apply to the range of a given species. Therefore, there is
uncertainty about the specific effects of climate change (and their
magnitude) on the pearl darter. However, climate change is almost
certain to affect aquatic habitats in the Pascagoula River basin
through increased water temperatures resulting in stronger storm surges
and more frequent droughts (Alder and Hostetler 2013, pp. 1-12), and
species with limited ranges, fragmented distributions, and small
population sizes are thought to be especially vulnerable to the effects
of climate change (Byers and Norris 2011, p. 18).
Summary of Factor E
The pearl darter's limited geographic range, fragmented
distribution within the Pascagoula River system, small population
numbers, and low genetic diversity threaten this species' long-term
viability. These threats are current and are likely to continue or
increase in the future, and would be exacerbated by climate change.
Cumulative Effects of Factors A Through E
The threats that affect the pearl darter are important on a threat-
by-threat basis but are even more significant in combination. Due to
the loss of the species from the Pearl River system, the pearl darter
is now confined to a single drainage system. The species continues to
be subjected to water quality degradation from point and nonpoint
source pollution in association with land-altering activities,
discharges from municipalities, and geomorphological changes from past
gravel mining. The laws and regulations directed at preventing water
quality degradation have been ineffective at providing for the
conservation of the pearl darter. Furthermore, these threats and their
effect on this species are exacerbated due to the pearl darter's small
population numbers, localized distribution, and low genetic diversity,
which reduce its genetic fitness and resilience to possible
catastrophic events. Though projecting possible synergistic effects of
climate change on the pearl darter is somewhat speculative, climate
change, and its effects of increased water temperatures leading to
stronger storms and more frequent droughts, will have a greater
negative impact on species with limited ranges and small population
sizes, such as the pearl darter. While these threats or stressors may
act in isolation, it is more probable that many stressors are acting
simultaneously (or in combination) on the pearl darter, having a
greater cumulative negative effect than any individual stressor or
threat.
Determination
We have carefully assessed the best scientific and commercial
information available regarding the past, present, and future threats
to the pearl darter. The pearl darter has been extirpated from the
Pearl River system, and it is now confined to the Pascagoula River
watershed. The species occurs in low numbers within its current range,
and continues to be at risk throughout all of its range due to the
immediacy, severity, and scope of threats from habitat degradation and
range curtailment (Factor A) and other natural or manmade factors
affecting its continued existence (Factor E). Existing regulatory
mechanisms have been inadequate in ameliorating these threats (Factor
D).
Anthropogenic activities, such as general land development,
agriculture and silviculture, oil and gas development (especially when
BMPs were not implemented during these activities), along with
inadequate sewage treatment, uncontrolled stormwater runoff, pulp mill
effluent, past gravel mining and resultant geomorphological changes,
and construction of dams or sills, have all contributed to the
degradation of stream habitats and water quality within this species'
range (Factor A). These land use activities have led to chemical and
physical changes in the main stem rivers and tributaries that continue
to affect the species through negative impacts to its habitat. Specific
water quality threats include inputs of sediments covering bottom
stream substrates, increased turbidity, and inputs of dissolved solids.
These threats, especially the inputs of dissolved solids, chemical-
laden effluent, sedimentation, and geomorphic changes, have had
profound negative effects on pearl darter populations, as demonstrated
in the Pearl River basin, and have been the primary factor in the
species' decline. Existing regulatory mechanisms (e.g., the Clean Water
Act) have provided for some improvements in water quality and habitat
conditions across the species' range, but these laws and regulations
have been inadequate in protecting the species' habitat (Factor D), as
evidenced by the extirpation of the species within the Pearl River
basin and by the number of section 303(d) listed streams within the
species'
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historical and current range. The pearl darter's vulnerability to these
threats is even greater due to its reduced range, scattered locations
of small populations, and low genetic diversity (Factor E).
The Act defines an endangered species as any species that is ``in
danger of extinction throughout all or a significant portion of its
range'' and a threatened species as any species ``that is likely to
become endangered throughout all or a significant portion of its range
within the foreseeable future.'' We find that the pearl darter is
likely to become endangered throughout all or a significant portion of
its range within the foreseeable future, based on the immediacy,
severity, and scope of the threats currently impacting the species.
Foreseeable future for this species was determined to be approximately
20 years, which is based on our best professional judgement of the
projected future conditions related to threats identified impacting
this species. The overall range has been reduced substantially, and the
remaining habitat and populations are threatened by a variety of
factors acting in combination to reduce the overall viability of the
species over time. The threats are not expected to change substantially
within this 20-year timeframe, as water quality degradation continues
to pose a risk locally despite existing regulations, and land
development and land-altering activities are expected to increase. The
risk of becoming endangered during this time is high because
populations confined to this single watershed are fragmented and
genetic diversity within the species is low. Many of the populations
are small and likely below the effective population size needed to
maintain long-term population viability which makes this species
particularly vulnerable to catastrophic events. Though there is
uncertainty about the magnitude of effects of climate change on the
pearl darter, the frequency and intensity of storms affecting the
Pascagoula River watershed are evident today and predicted to increase
during this timeframe.
We find that endangered species status is not appropriate for this
species. Despite low population numbers and numerous threats, the
Chickasawhay and Leaf Rivers, within the upper Pascagoula River
drainage, appear to support reproducing populations. In addition, the
magnitude of threats is considered to be moderate overall, since the
threats are having a localized impact on the species and its habitat.
For example, water quality degradation, the most prevalent threat, is
not as pervasive within areas where BMPs are utilized, and geomorphic
changes caused by historic sand and gravel mining are also sporadic
within its habitat. Therefore, on the basis of the best available
scientific and commercial information, we are listing the pearl darter
as threatened in accordance with sections 3(6) and 4(a)(1) of the Act.
Under the Act and our implementing regulations, a species may
warrant listing if it is endangered or threatened throughout all or a
significant portion of its range. Because we have determined that the
pearl darter is threatened throughout all of its range, no portion of
its range can be ``significant'' for purposes of the definitions of
``endangered species'' and ``threatened species.'' See the Final Policy
on Interpretation of the Phrase ``Significant Portion of Its Range'' in
the Endangered Species Act's Definitions of ``Endangered Species'' and
``Threatened Species'' (79 FR 37577, July 1, 2014). While it is the
Service's position under the Policy that undertaking no further
analysis of ``significant portion of its range'' in this circumstance
is consistent with the language of the Act, we recognize that the
Policy is currently under judicial review, so we also took the
additional step of considering whether there could be any significant
portions of the species' range where the species is in danger of
extinction. We evaluated whether there is substantial information
indicating that there are any portions of the species' range: (1) That
may be ``significant,'' and (2) where the species may be in danger of
extinction. In practice, a key part of identifying portions appropriate
for further analysis is whether the threats are geographically
concentrated. The threats affecting the species are throughout its
entire range; therefore, there is not a meaningful geographical
concentration of threats. As a result, even if we were to undertake a
detailed ``significant portion of its range'' analysis, there would not
be any portions of the species' range where the threats are harming the
species to a greater degree such that it is in danger of extinction in
that portion.
Critical Habitat
Section 3(5)(A) of the Act defines critical habitat as ``(i) the
specific areas within the geographical area occupied by the species, at
the time it is listed...on which are found those physical or biological
features (I) essential to the conservation of the species and (II)
which may require special management considerations or protection; and
(ii) specific areas outside the geographical area occupied by the
species at the time it is listed...upon a determination by the
Secretary that such areas are essential for the conservation of the
species.''
Section 4(a)(3) of the Act and implementing regulations (50 CFR
424.12) require that we designate critical habitat at the time a
species is determined to be an endangered or threatened species, to the
maximum extent prudent and determinable. In our September 21, 2016,
proposed rule to list the darter (81 FR 64857), we determined that
designation of critical habitat was prudent. We also found that
critical habitat for the pearl darter was not determinable because the
specific information sufficient to perform the required analysis of the
impacts of the designation is currently lacking, such as information on
areas to be proposed for designation and the potential economic impacts
associated with designation of these areas. We are continuing the
process of obtaining information on the economic impacts of our
critical habitat designation, and, once this process is completed, we
intend to publish our proposed critical habitat designation for the
pearl darter in the Federal Register and request public input.
Available Conservation Measures
Conservation measures provided to species listed as endangered or
threatened species under the Act include recognition, recovery actions,
requirements for Federal protection, and prohibitions against certain
practices. Recognition through listing results in public awareness, and
conservation by Federal, State, Tribal, and local agencies, private
organizations, and individuals. The Act encourages cooperation with the
States and requires that recovery actions be carried out for all listed
species. The protection required by Federal agencies and the
prohibitions against certain activities are discussed, in part, below.
The primary purpose of the Act is the conservation of endangered
and threatened species and the ecosystems upon which they depend. The
ultimate goal of such conservation efforts is the recovery of these
listed species, so that they no longer need the protective measures of
the Act. Subsection 4(f) of the Act requires the Service to develop and
implement recovery plans for the conservation of endangered and
threatened species. The recovery planning process involves the
identification of actions that are necessary to halt or reverse the
species' decline by addressing the threats to its survival and
recovery. The goal of this process is to restore listed species to a
point where they are secure, self-sustaining, and functioning
components of their ecosystems.
[[Page 43895]]
Recovery planning includes the development of a recovery outline
shortly after a species is listed and preparation of a draft and final
recovery plan. The recovery outline guides the immediate implementation
of urgent recovery actions and describes the process to be used to
develop a recovery plan. Revisions of the plan may be done to address
continuing or new threats to the species, as new substantive
information becomes available. The recovery plan identifies site-
specific management actions that set a trigger for review of the five
factors that control whether a species remains endangered or may be
downlisted or delisted, and methods for monitoring recovery progress.
Recovery plans also establish a framework for agencies to coordinate
their recovery efforts and provide estimates of the cost of
implementing recovery tasks. Recovery teams (composed of species
experts, Federal and State agencies, nongovernmental organizations, and
stakeholders) are often established to develop recovery plans. When
completed, the recovery outline, draft recovery plan, and the final
recovery plan will be available on our Web site (http://www.fws.gov/endangered) or from our Mississippi Ecological Services Field Office
(see FOR FURTHER INFORMATION CONTACT).
Implementation of recovery actions generally requires the
participation of a broad range of partners, including other Federal
agencies, States, Tribal, nongovernmental organizations, businesses,
and private landowners. Examples of recovery actions include habitat
restoration (e.g., restoration of native vegetation), research, captive
propagation and reintroduction, and outreach and education. The
recovery of many listed species cannot be accomplished solely on
Federal lands because their range may occur primarily or solely on non-
Federal lands. To achieve recovery of these species requires additional
cooperative conservation efforts on private, State, and Tribal lands.
Following publication of this final listing rule, funding for
recovery actions will be available from a variety of sources, including
Federal budgets, State programs, and cost share grants for non-Federal
landowners, the academic community, and nongovernmental organizations.
In addition, pursuant to section 6 of the Act, the State of Mississippi
will be eligible for Federal funds to implement management actions that
promote the protection or recovery of the pearl darter. Information on
our grant programs that are available to aid species recovery can be
found at: http://www.fws.gov/grants.
Please let us know if you are interested in participating in
recovery efforts for the pearl darter. Additionally, we invite you to
submit any new information on this species whenever it becomes
available and any information you may have for recovery planning
purposes (see FOR FURTHER INFORMATION CONTACT).
Section 7(a) of the Act requires Federal agencies to evaluate their
actions with respect to any species that is listed as an endangered or
threatened species and with respect to its critical habitat, if any is
designated. Regulations implementing this interagency cooperation
provision of the Act are codified at 50 CFR part 402. Section 7(a)(1)
requires Federal agencies to utilize their authorities in furtherance
of the purposes of the Act by carrying out programs for the
conservation of endangered and threatened species listed pursuant to
section 4 of the Act. 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 any endangered
or threatened species or destroy or adversely modify its critical
habitat. If a Federal action may affect a listed species or its
critical habitat, the responsible Federal agency must enter into
consultation with the Service.
Federal agency actions within the species' habitat that may require
consultation as described in the preceding paragraph include actions on
lands under ownership by the U.S. Army Corps of Engineers, the issuance
of section 404 Clean Water Act permits by the U.S. Army Corps of
Engineers, construction and maintenance of gas and oil pipelines and
power line rights-of-way by the Federal Energy Regulatory Commission,
Environmental Protection Agency pesticide registration, construction
and maintenance of roads or highways by the Federal Highway
Administration, and funding of various projects administered by the
U.S. Department of Agriculture's Natural Resources Conservation Service
and the Federal Emergency Management Agency.
Under section 4(d) of the Act, the Service has discretion to issue
regulations that we find necessary and advisable to provide for the
conservation of threatened species. The Act and its implementing
regulations set forth a series of general prohibitions and exceptions
that apply to threatened wildlife. The prohibitions of section 9(a)(1)
of the Act, as applied to threatened wildlife and codified at 50 CFR
17.31, make it illegal for any person subject to the jurisdiction of
the United States to take (which includes harass, harm, pursue, hunt,
shoot, wound, kill, trap, capture, or collect; or to attempt any of
these) threatened wildlife within the United States or on the high
seas. In addition, it is unlawful to import; export; deliver, receive,
carry, transport, or ship in interstate or foreign commerce in the
course of commercial activity; or sell or offer for sale in interstate
or foreign commerce any listed species. It is also illegal to possess,
sell, deliver, carry, transport, or ship any such wildlife that has
been taken illegally. Certain exceptions apply to employees of the
Service, the National Marine Fisheries Service, other Federal land
management agencies, and State conservation agencies.
We may issue permits to carry out otherwise prohibited activities
involving threatened wildlife under certain circumstances. Regulations
governing permits are codified at 50 CFR 17.32. With regard to
threatened wildlife, a permit may be issued for the following purposes:
For scientific purposes, to enhance the propagation or survival of the
species, and for incidental take in connection with otherwise lawful
activities. There are also certain statutory exemptions from the
prohibitions, which are found in sections 9 and 10 of the Act.
It is our policy, as published in the Federal Register on July 1,
1994 (59 FR 34272), to identify to the maximum extent practicable at
the time a species is listed, those activities that would or would not
constitute a violation of section 9 of the Act. The intent of this
policy is to increase public awareness of the effect of a final listing
on proposed and ongoing activities within the range of a listed
species. Based on the best available information, the following actions
are unlikely to result in a violation of section 9, if these activities
are carried out in accordance with existing regulations, permit
requirements, or certification programs; this list is not
comprehensive:
(1) Normal agricultural and silvicultural practices, including
herbicide and pesticide use, which are carried out in accordance with
existing regulations, permit and label requirements, and certified best
management practices (i.e., Sustainable Forestry Initiative, Forest
Stewardship Council, and American Tree Farm System).
(2) Normal residential and urban landscape activities, such as
mowing, edging, fertilizing, etc.
(3) Normal pipeline/transmission line easement maintenance.
(4) Normal bridge, culvert, and roadside maintenance consistent
with
[[Page 43896]]
appropriate best management practices for these activities.
Based on the best available information, the following activities
may potentially result in a violation of section 9 of the Act; this
list is not comprehensive:
(1) Unauthorized handling or collecting of the species.
(2) Introduction of nonnative fish that compete with or prey upon
the pearl darter.
(3) Unlawful discharge or dumping of toxic chemicals, contaminants,
sediments, fracking and oil waste water, waste water effluent, or other
pollutants into waters supporting the pearl darter that kills or
injures individuals, or otherwise impairs essential life-sustaining
behaviors such as spawning, feeding, or sheltering.
(4) Destruction or alteration of the species' habitat (e.g.,
unpermitted instream dredging, impoundment, water diversion or
withdrawal, channelization, discharge of fill material, modification of
tributaries, channels, or banks) that impairs essential behaviors such
as spawning, feeding, or sheltering, or results in killing or injuring
a pearl darter.
(5) Unpermitted gravel mining, oil and gas processes, silviculture,
and agricultural processes that result in direct or indirect
destruction of riparian bankside habitat or in channel habitat in
waters supporting the pearl darter that kills or injures individuals,
or otherwise impairs essential life-sustaining behaviors such as
spawning, feeding, or sheltering.
Questions regarding whether specific activities would constitute a
violation of section 9 of the Act should be directed to the Mississippi
Ecological Services Field Office (see FOR FURTHER INFORMATION CONTACT).
Required Determinations
National Environmental Policy Act (42 U.S.C. 4321 et seq.)
We have determined that environmental assessments and environmental
impact statements, as defined under the authority of the National
Environmental Policy Act, need not be prepared in connection with
listing a species as an endangered or threatened species under the
Endangered Species Act. We published a notice outlining our reasons for
this determination in the Federal Register on October 25, 1983 (48 FR
49244).
Government-to-Government Relationship With Tribes
In accordance with the President's memorandum of April 29, 1994
(Government-to-Government Relations with Native American Tribal
Governments; 59 FR 22951), Executive Order 13175 (Consultation and
Coordination With Indian Tribal Governments), and the Department of the
Interior's manual at 512 DM 2, we readily acknowledge our
responsibility to communicate meaningfully with recognized Federal
Tribes on a government-to-government basis. In accordance with
Secretarial Order 3206 of June 5, 1997 (American Indian Tribal Rights,
Federal-Tribal Trust Responsibilities, and the Endangered Species Act),
we readily acknowledge our responsibilities to work directly with
tribes in developing programs for healthy ecosystems, to acknowledge
that tribal lands are not subject to the same controls as Federal
public lands, to remain sensitive to Indian culture, and to make
information available to tribes. The pearl darter is not known to occur
within any tribal lands or waters.
References Cited
A complete list of references cited in this rulemaking is available
on the Internet at http://www.regulations.gov and upon request from the
Mississippi Ecological Services Field Office (see FOR FURTHER
INFORMATION CONTACT).
Authors
The primary authors of this final rule are the staff members of the
Mississippi Ecological Services Field Office.
List of Subjects in 50 CFR Part 17
Endangered and threatened species, Exports, Imports, Reporting and
recordkeeping requirements, Transportation.
Regulation Promulgation
Accordingly, we amend part 17, subchapter B of chapter I, title 50
of the Code of Federal Regulations, as follows:
PART 17--ENDANGERED AND THREATENED WILDLIFE AND PLANTS
0
1. The authority citation for part 17 continues to read as follows:
Authority: 16 U.S.C. 1361-1407; 1531-1544; and 4201-4245,
unless otherwise noted.
0
2. Amend Sec. 17.11(h) by adding an entry for ``Darter, Pearl'' to the
List of Endangered and Threatened Wildlife in alphabetical order under
``FISHES'' to read as follows:
Sec. 17.11 Endangered and threatened wildlife.
* * * * *
(h) * * *
----------------------------------------------------------------------------------------------------------------
Listing citations and
Common name Scientific name Where listed Status applicable rules
----------------------------------------------------------------------------------------------------------------
* * * * * * *
FISHES
* * * * * * *
Darter, Pearl.................. Percina aurora.... Wherever found.... T 82 FR [insert Federal
Register page where
the document begins],
9/20/2017.
* * * * * * *
----------------------------------------------------------------------------------------------------------------
Date: September 7, 2017.
James W. Kurth,
Acting Director, U.S. Fish and Wildlife Service.
[FR Doc. 2017-20069 Filed 9-19-17; 8:45 am]
BILLING CODE 4333-15-P