[Federal Register Volume 79, Number 125 (Monday, June 30, 2014)]
[Rules and Regulations]
[Pages 37077-37103]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2014-14761]
[[Page 37077]]
Vol. 79
Monday,
No. 125
June 30, 2014
Part III
Department of the Interior
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Fish and Wildlife Service
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50 CFR Part 17
Endangered and Threatened Wildlife and Plants; Reclassification of the
U.S. Breeding Population of the Wood Stork From Endangered to
Threatened; Final Rule
Federal Register / Vol. 79 , No. 125 / Monday, June 30, 2014 / Rules
and Regulations
[[Page 37078]]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[Docket No. FWS-R4-ES-2012-0020; FXES11130900000C2-134-FF09E32000]
RIN 1018-AX60
Endangered and Threatened Wildlife and Plants; Reclassification
of the U.S. Breeding Population of the Wood Stork From Endangered to
Threatened
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Final rule.
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SUMMARY: We, the U.S. Fish and Wildlife Service (Service or USFWS),
reclassify the United States (U.S.) breeding population of the wood
stork from endangered to threatened under the Endangered Species Act of
1973, as amended (Act). Further, we establish the U.S. breeding
population in Alabama, Florida, Georgia, North Carolina, Mississippi,
and South Carolina as a distinct population segment (DPS). The
endangered designation no longer correctly reflects the status of the
DPS due to improvement in its overall status. This action is based on a
review of the best available scientific and commercial data, which
indicate that the U.S. wood stork DPS is not presently in danger of
extinction across its range. While habitat loss and fragmentation
continues to impact the U.S. wood stork DPS, the increase in the
abundance of the breeding population and significant expansion of the
breeding range reduce the severity and magnitude of these threats.
DATES: This rule becomes effective on July 30, 2014.
ADDRESSES: This final rule, as well as comments and materials received
in response to the proposed rule, are available on the Internet at
http://www.regulations.gov at Docket Number [FWS-R4-ES-2012-0020].
Comments and materials received, as well as supporting documentation
used in preparation of this rule, will be available for public
inspection, by appointment, during normal business hours at: U.S. Fish
and Wildlife Services, North Florida Ecological Services Field Office,
7915 Baymeadows Way, Suite 200, Jacksonville, FL 32256.
FOR FURTHER INFORMATION CONTACT: Jay Herrington, North Florida
Ecological Services Field Office, (see ADDRESSES); by telephone at 904-
731-3336; or by facsimile (fax) at 904-731-3045. If you use a
telecommunications device for the deaf (TDD), please call the Federal
Information Relay Service (FIRS) at 800-877-8339.
SUPPLEMENTARY INFORMATION:
Executive Summary
Why We Need To Publish a Rule
In September 2007, we completed a 5-year status review,
which included a recommendation to reclassify the U.S. breeding
population of the wood stork from endangered to threatened.
In May 2009, we received a petition to reclassify the U.S.
breeding population of wood stork; the petition incorporated the
Service's 5-year review as its sole supporting information.
On September 21, 2010, we published a 90-day finding that
the petition presented substantial information indicating that
reclassifying the wood stork may be warranted (75 FR 57426). We
requested information that would assist us in our status review.
On December 26, 2012, we published a 12-month finding that
the petitioned action was warranted and concurrently a proposed rule to
reclassify the U.S. breeding population of the wood stork from
endangered to threatened and designate this population as a distinct
population segment (DPS) (77 FR 75947). We requested peer and public
review of the proposed rule.
Summary of the Major Provisions of This Final Rule
We reclassify the U.S. breeding population of wood stork
from endangered to threatened.
We determine that the U.S. breeding population of wood
stork is a DPS.
We amend the List of Endangered and Threatened Wildlife
(50 CFR 17.11(h)) to reflect the status change to threatened and that
the U.S. wood stork DPS is found in the States of Alabama, Florida,
Georgia, Mississippi, North Carolina, and South Carolina.
The Basis for the Action
The U.S. breeding population of wood stork was listed
under the Act in 1984, prior to publication of the joint policy of the
National Marine Fisheries Service and U.S. Fish and Wildlife Service
(Services) regarding the recognition of distinct vertebrate population
segments (61 FR 4722). We find that the U.S. breeding population of
wood stork meets the elements of the Services' DPS policy and is a
valid DPS (U.S. Wood Stork DPS).
When the U.S. breeding population of wood stork was listed
in 1984, the population was known to occur in Alabama, Florida,
Georgia, and South Carolina with breeding and nesting primarily in
south and central Florida with a small number of nesting colonies in
north Florida, Georgia, and South Carolina. Currently wood storks occur
in Alabama, Florida, Georgia, Mississippi, North Carolina, and South
Carolina, with breeding and nesting documented in Florida, Georgia,
North Carolina, and South Carolina.
The best available scientific and commercial data indicate
that, since the U.S. breeding population of wood stork was listed as
endangered in 1984, the breeding population has been increasing and its
breeding range has expanded significantly.
We have had 3-year population averages of total nesting
pairs of wood storks higher than 6,000 nesting pairs since 2003. In
addition, productivity appears to be sufficient to support a growing
population. However, the 5-year average number of nesting pairs is
still below the benchmark of 10,000 nesting pairs identified in the
recovery plan for delisting.
As a result of continued loss, fragmentation, and
modification of wetland habitats in parts of the wood stork's range, we
determine that the U.S. wood stork DPS meets the definition of a
threatened species under section 3 of the Act, and we are reclassifying
it from endangered to threatened.
Background
Summary of Comments and Recommendations
In the proposed rule published on December 26, 2012 (77 FR 75947),
we requested that all interested parties submit written comments on the
proposal by February 25, 2013. We also contacted appropriate Federal
and State agencies, scientific experts and organizations, and other
interested parties and invited them to comment on the proposal. In
addition, the Service notified affected Tribes about the proposed rule.
A newspaper notice inviting general public comment was published in
several newspapers in the southeastern United States. We did not
receive any requests for a public hearing; therefore, none were
conducted.
Peer Review, State, and Tribal Comments
In accordance with our peer review policy published on July 1, 1994
(59 FR 34270), we solicited independent expert opinions from four
individuals who have scientific expertise that included familiarity
with wood storks and their habitat, biological needs, recovery
[[Page 37079]]
efforts, threats, and conservation biology principles. We invited peer
reviewers to comment on the specific assumptions and conclusions in the
proposed reclassification of the U.S. breeding population. We received
comments from all four of the peer reviewers. The peer reviewers
supported our conclusions and provided additional information,
clarifications, and suggestions to improve the final rule.
Section 4(b)(5)(A)(ii) of the Act states that the Secretary must
give actual notice of a proposed regulation under section 4(a) to the
State agency in each State in which the species is believed to occur,
and invite the comments of such agency. Section 4(i) of the Act states,
``the Secretary shall submit to the State agency a written
justification for his failure to adopt regulations consistent with the
agency's comments or petition.'' The Service submitted the proposed
regulation to the States of Alabama, Florida, Georgia, Mississippi,
North Carolina, and South Carolina. We received formal comments from
the Florida Fish and Wildlife Conservation Commission, Georgia
Department of Natural Resources (DNR), and North Carolina Wildlife
Resources Commission. All three agencies support reclassification of
the wood stork from endangered to threatened. The Mississippi Museum of
Natural Science provided additional information about wood storks in
Mississippi for the Service to consider.
In addition, the Service notified affected Tribes about the
proposed rule. We did not receive any comments from Tribes.
(1) Comment: A peer reviewer and the Georgia DNR stated concerns
and challenges that may influence future recovery of the wood stork due
to climate change.
Our Response: Aspects of climate change such as sea level rise and
associated tidal or storm surges, changes in rainfall patterns, storm
frequency and intensity, and seasonal changes in temperature could
affect the extent and quality of wood stork habitat, nesting success,
and the range of the species. Any of these changes could impact the
future viability of wood stork populations, either positively or
negatively. Our assessments related to habitat (Factor A, below) and
other natural and human influences (Factor E, below) have been expanded
to more directly address observed changes and plausible projections of
climate change, and related possible impacts to the wood stork.
Although the information did not alter our decision to change the
status of the wood stork DPS form endangered to threatened, we concur
that the effects of climate change will influence the recovery of the
wood stork.
As additional data and modeling become available from various
scientific sources, and as conservation recommendations from the
Landscape Conservation Cooperatives and others are developed for
addressing the varied effects of climate change and its interactions
with other conditions, it will no doubt inform recovery planning and
implementation. We intend to further address climate change effects as
we update the wood stork recovery plan, using the best scientific
information available at that time.
(2) Comment: A peer reviewer suggested adding information and
citations regarding the accuracy of the annual synoptic nesting
surveys.
Our Response: We added information regarding synoptic nesting
surveys in the Rangewide Status and Demographics section of this
document. Rodgers et al. (1995, p. 656) indicates that aerial surveys
generally underestimate counts and Rodgers et al. (2005, p. 230)
indicates that by including ground counts in the survey and surveying a
large proportion of the nesting colonies, the variability can be
reduced. We have also incorporated this recommendation into the annual
synoptic nest survey protocol.
(3) Comment: Peer reviewers provided additional information and
citations on several topics including: natural colony turnover rates,
colony distribution in the northern range, colony threats and
management, mercury, avian malaria and pythons.
Our Response: We incorporated this information and the citations
directly into the final determination.
(4) Comment: The Georgia DNR commented that many years of
productivity data exist for colonies in Georgia, though only data from
2004 and 2005 were included in the reclassification proposal. Georgia
DNR compiled, assessed, and provided the productivity data that it has
collected for 32 colonies beginning in 1983, which represents more than
6,400 nests, representing 158 colony-years.
Our Response: We incorporated the data into the Mating and
Reproduction section of this document. We have also compiled the
productivity data from our files for the U.S. breeding population of
wood storks and have made it available through our Web site at http://www.fws.gov/northflorida/WoodStorks/wood-storks.htm. We note that
methods used to collect productivity data vary by colony and by area
and that the USFWS recommends, when feasible, utilizing Rodgers (2005)
Protocol for Monitoring the Reproductive Success of Wood Storks in the
Southeast United States as the recommended scientific method for
collecting productivity data to assess recovery.
Public Comments
We received 16 comments and letters from the public: 12
individuals, a timber company, and 3 conservation organizations. All
substantive information provided during the comment period has either
been incorporated directly into this final determination or addressed
below.
(5) Comment: Reclassification/downlisting should not occur when FWS
lacks data to determine whether one of the criteria for
reclassification/downlisting has been met.
Our Response: Recovery plans are useful tools to guide conservation
activities and to gauge the status of the species. However, there are
many paths to accomplishing recovery of a species, and recovery may be
achieved without all recovery criteria being fully met. The overriding
considerations in determining listing status are the five factors
listed in section 4(a)(1) of the Act. Current data indicate that since
the U.S. breeding population of wood stork was listed as endangered in
1984, it has been increasing and the breeding range has expanded
significantly. Productivity has supported a growing population,
reducing the relative negative effects of the remaining threats to this
species to the extent that the species is no longer in danger of
extinction throughout all or a significant portion of its range. On
balance, and in consideration of the best scientific and commercial
information available, the Service believes the species best meets the
definition of a threatened species. For more details of our status
review, see Summary of Factors Affecting the Species. For additional
information on the role of recovery plans, see the Recovery Plan
section of this document.
(6) Comment: Wood stork populations in south Florida are too low
and nesting success is too variable to warrant reclassification.
Our Response: We have seen substantial population growth, but we
acknowledge that wood storks have had variable nesting success in south
Florida. However, nesting numbers in south Florida have increased since
1986 with nesting goals being met in 5 of the past 12 years (Frederick
2013, p. 35; Table 21). We believe the final rule adequately considers
both the threats and positive management actions in south Florida and,
in conjunction with improvements throughout an expanded range, the
species warrants
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reclassification from endangered to threatened. The U.S. wood stork DPS
revised status as threatened acknowledges that threats to the long-term
viability of the species remain.
We share the concern that the timing of nesting is not improving in
the Everglades and productivity has been variable and in some years
low. As several commenters noted, in 2012, most of the wood stork nests
in Everglades National Park failed. Later nesting increases the risk of
mortality of nestlings that have not fledged prior to the onset of the
wet season (Frederick 2012, p. 44). We acknowledge that restoration of
key historical hydropatterns has not fully occurred under current water
management regimes. These restoration efforts take time, and will need
to be adjusted as appropriate in light of emerging information and
conditions related to a changing climate.
Additionally, we share the concern regarding the lack of wood stork
nesting at Corkscrew Swamp Sanctuary in recent years. Our recovery
partners have indicated and documented that the loss of shallow, short
hydroperiod wetlands is likely a leading factor causing or contributing
to this issue. We also note that, during this time period, the average
rainfall for the Southwest Coast basin has been below normal (http://www.sfwmd.gov/portal/page/portal/xweb%20weather/rainfall%20historical%20%28year-to-date%29 for 2010-2012), resulting in
drought conditions, which likely contributed to, magnified, or caused
this problem. Various effects of a changing climate could influence the
availability of suitable nesting and foraging habitat conditions in
both negative and positive ways, depending on the magnitude and timing
of changes in temperature and precipitation. We intend to work with
partners to use the best scientific information available as we develop
specific recovery actions regarding mitigation and restoration of
shallow, short hydroperiod wetlands within the core foraging area of
Corkscrew Swamp Sanctuary and other colonies as necessary.
Table 3 \1\--Three-Year Averages of Wood Stork Nesting
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South Florida
3-Year averages Everglades \1\ \2\ total Florida total U.S. total \3\
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1999-2001....................................... 1,538
2000-2002....................................... 1,868
2001-2003....................................... 1,596 3,179 4,838 7,417
2002-2004....................................... 1,191 2,889 5,332 8,349
2003-2005....................................... 742 2,109 4,278 7,588
2004-2006....................................... 800 2,814 4,749 8,410
2005-2007....................................... 633 2,516 3,691 7,086
2006-2008....................................... 552 2,374 3,536 7,268
2007-2009....................................... 1,468 3,393 4,273 7,748
2008-2010....................................... 1,736 3,700 5,031 8,993
2009-2011....................................... 2,263 4,628 6,183 10,147
2010-2012....................................... 1,182 3,022 4,553 8,724
2011-2013....................................... 1,686 3,671 5,593 9,692
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\1\ Comprehensive Everglades Restoration Program Goal: 3-year average of 1,500-2,500; (Frederick 2013, p. 36,
Table 21); Recovery Goal: 5-year average of 2,500.
\2\ Broward, Charlotte, Collier, Hardee, Hendry, Indian River, Lee, Martin, Miami-Dade, Monroe, Osceola, Palm
Beach, Polk, Sarasota, St. Lucie; South Florida MSRP Goal: 5-year average of 3,500 (USFWS 2001).
\3\ Florida, Georgia, North Carolina, South Carolina; Reclassification Goal: 3-year average of 6,000; Recovery
Goal: 5-year average of 10,000 (USFWS 2013).
(7) Comment: Several commenters stated that, under the Act, less
protection is afforded to a threatened species than to an endangered
species, referencing the Service's ``What Is the Difference Between
Endangered and Threatened?'' document at http://www.fws.gov/endangered/esa-library/pdf/t-vs-e.pdf. Another commenter specifically stated that
downlisting the wood storks from endangered to threatened would allow
USFWS to scale back protection, expanding the circumstances under which
``take'' is permitted, and under which permits for ``take'' may be
issued.
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\1\ Table 3 has been created to address certain comments
received. We have named it Table 3 even though it is included here
before Tables 1 and 2, so as not to confuse readers by changing the
Table numbering in the final rule with respect to the numbering in
the proposed rule. Information from this table has been incorporated
directly into the Background section of the final rule without
repeating the entire table.
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Our Response: Section 4(d) of the Act allows the Service to issue
such regulations that the Secretary of the Interior deems necessary and
advisable to conserve the species. It must be noted, however, that by
regulation at 50 CFR 17.31(a), the Service affords a threatened species
the same protections and prohibitions under section 9 of the Act as
those given to endangered species (with an exception pertaining to take
by an authorized agent of a State) unless or until a 4(d) rule is
specifically promulgated. As no 4(d) rule was proposed for the U.S.
wood stork DPS, the section 9 prohibitions against take continue to
apply per 50 CFR 17.31(a) and, therefore, reclassification will not
significantly change the protection afforded this species under the
Act.
(8) Comment: The Service should ``designate'' two regions of wood
stork habitat, ``South Florida'' and ``Coastal Tidal Wetlands,'' as
``Significant Portions of the Range'' as the Service considers the next
steps for recovery.
Our Response: ``Significant portion of the range,'' a term found in
the definitions of endangered and threatened (Section 3 of the Act), is
a consideration in the determination of whether the threats in one
portion of a species' range are of such impact to the overall viability
of the species that it warrants listing throughout the entire range.
Current data show that the breeding range has now almost doubled in
extent and shifted northward along the Atlantic coast as far as
southeastern North Carolina. As a result, dependence of wood storks on
any specific wetland complex has been reduced. See the Significant
Portion of the Range Analysis of this rule for our detailed discussion
of why South Florida does not represent a significant portion of the
range. In addition, wood storks are known to utilize numerous habitat
types. These include coastal tidal
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wetlands and marsh, lakes, and ponds, interior marsh systems, and
manmade impoundments (e.g., Harris Neck NWR and Washo Reserve). This
ability is advantageous for the wood stork and is one of the reasons
for its improved status.
However, the commenter's recommendations will be considered during
future recovery planning in determining whether the South Florida,
Coastal Tidal Wetlands, or other regions should be considered as
management or recovery units for the species. We intend to continue
working with partners under our recovery program to restore and protect
all types of habitat used by the U.S. wood stork DPS.
(9) Comment: The Service should delay implementation of the
proposed reclassification rule until the science questions and gaps,
data analyses, and regulatory deficiencies have all been addressed.
Our Response: The wood stork no longer meets the definition of
endangered. The rule recognizes the improved status of the species from
endangered (i.e., currently in danger of extinction) to threatened
(i.e., one which is likely to become an endangered species in the
foreseeable future) as a result of documented improvement in the
species' population, and is based on the best available science
including information regarding ongoing and likely foreseeable changes
in conditions that are relevant to the DPS. The species' revised status
as threatened acknowledges that threats to the long-term viability of
the species remain. Implementation of the rule will not reduce any
protective measures currently in place.
(10) Comment: By citing predictions that the Comprehensive
Everglades Restoration Program (CERP) restoration, when fully realized,
will result in large, sustainable, breeding populations of wading
birds, the Service dismisses the potential for wood storks to be
biologically extirpated from the Everglades. The commenter is reluctant
to consider ongoing and long-term restoration efforts due to the multi-
generational timeframe of the anticipated benefits.
Our Response: As Table 2 (see Background discussion) shows, wood
storks continue to nest in South Florida (including the Everglades);
for 7 of the last 10 years there have been over 1,200 nesting pairs. In
addition, Table 3 indicates that since 2007, 3-year averages of nesting
pairs in South Florida and the Everglades have been over 3,000 and
1,100, respectively. We acknowledge that productivity has been variable
in South Florida; however, wood storks continue to nest in this area.
Wood storks are a long-lived species that demonstrates considerable
variation in the habitat conditions it is able to utilize and in
population numbers in response to changing hydrological conditions. As
indicated in our analysis of the factors that are a basis for
determining whether the DPS meets the definition of an endangered or
threatened species, and in our section on ``Significant Portion of the
Range,'' we have carefully considered various potential changes to the
DPS. This includes recognizing that CERP restoration efforts and their
outcomes in relation to the wood stork in South Florida may differ from
what has been expected in the past, particularly due to the potential
effects of climate change, and it also recognizes that adjustments in
those restoration efforts may be needed as new information and
conditions emerge. This does not mean, however, that we believe the
data currently available support a conclusion that wood storks are
likely to be biologically extirpated from the Everglades.
(11) Comment: The proposed rule did not contain analysis of any of
the available models projecting sea level rise within the wood stork's
breeding range.
Our Response: Please see our response to Peer Review Comment 1 and
the information on projections of sea level rise that we have included,
particularly in the material presented under Factor A, below.
(12) Comment: The conservation of existing shallow wetlands and
restoration of former shallow wetlands is essential to stabilizing and
recovery of the wood stork in South Florida.
Our Response: We agree and intend to further address this as a
priority recovery action with partners in South Florida. We note also
such actions will need to consider likely changing conditions (e.g.,
those that may result from sea level rise and associated tidal and
storm surge, as well as changes in precipitation and other variables
that may influence the near-term and long-term availability of suitable
habitat conditions).
Summary of Changes From the Proposed Rule
During the comment period, peer reviewers provided additional
information and citations on several topics including: Natural colony
turnover rates, colony distribution in the northern range, colony
threats and management, mercury, avian malaria, and pythons. We
incorporated this information and the citations directly into this
final rule. State agencies provided updated productivity data that we
added to the final rule along with additional productivity data we
pulled and evaluated from sources. We also added information and
citations regarding the accuracy of the annual synoptic nesting surveys
and 2012 and 2013 data counts to Table 1 and Table 2. In addition,
based on comments received, we provided more details about ongoing and
projected climate change and associated effects in relation to the wood
stork DPS covered by this rule. None of these changes from the proposed
rule altered our conclusion that the DPS now meets the Act's definition
of a threatened species.
In this final rule, we intend to discuss only those topics directly
relevant to the reclassification and new information provided during
the open comment period. For more information on the biology of this
species (specifically the Taxonomy and Species Description, Life Span,
and Feeding sections), refer to the 12-month finding and proposed rule
to reclassify the U.S. breeding population of the wood stork which
published in the Federal Register on December 26, 2012 (77 FR 75947).
The biological information has been updated with literature and
information provided during the public comment period and from our
files. The following section summarizes information found in a large
body of published literature and reports, including the revised
recovery plan for the U.S. breeding population of the wood stork (USFWS
1997), The Birds of North America Online species account for wood stork
(Coulter et al. 1999), and the South Florida Multi-Species Recovery
Plan (USFWS 1999).
Mating and Reproduction
Wood storks are seasonally monogamous, probably forming a new pair
bond every season. First breeding has been documented at 3 and 4 years
old. Nest initiation varies geographically. Wood storks can lay eggs as
early as October and as late as June in Florida (Rodgers 1990, pp. 48-
51). Wood storks in north Florida, Georgia, and South Carolina initiate
nesting on a seasonal basis regardless of environmental conditions
(USFWS 1997, p. 6). They lay eggs from March to late May, with fledging
occurring in July and August. Historically, nest initiation in south
Florida was in November to January; however, in response to the altered
habitat conditions (wetland drainage, hydroperiod alteration) in south
Florida, wood storks nesting in Everglades National Park and in the Big
Cypress
[[Page 37082]]
region of Florida have delayed initiation of nesting to February or
March in most years since the 1970s. Colonies that start after January
in south Florida risk having young in the nests when May-June rains
flood marshes and disperse fish, which can cause nest abandonment.
Frederick (2012, p. 44) states that later nesting increases the risk of
mortality of nestlings that have not fledged prior to the onset of the
wet season, which is likely the difference between the south Florida
segment of the population being a source or a sink to the wood stork
population. Based upon their analysis of fledgling survival,
Borkhataria et al. 2012 (p. 525) also note the possibility that south
Florida is acting as a population sink.
Females generally lay a single clutch of two to five eggs per
breeding season, but the average is three eggs. Females sometimes lay a
second clutch if nest failure occurs early in the season (Coulter et
al. 1999, p. 11). Average clutch size may increase during years of
favorable water levels and food resources. Incubation requires about 30
days and begins after the female lays the first one or two eggs.
Nestlings require about 9 weeks for fledging, but the young return to
the nest for an additional 3 to 4 weeks to be fed. Actual colony
production measurements are difficult to determine because of the
prolonged fledging period, during which time the young return daily to
the colony to be fed.
Wood storks experience considerable variation in production among
colonies, regions, and years in response to local and regional habitat
conditions and food availability (Kahl 1964, p. 115; Ogden et al. 1978,
pp. 10-14; Clark 1978, p. 183; Rodgers and Schwikert 1997, pp. 84-85).
Several recent studies documented production rates to be similar to
rates published between the 1970s and 1990s. Rodgers et al. (2008, p.
25) reported a combined production rate for 21 north- and central-
Florida colonies from 2003 to 2005 of 1.19 0.09 fledglings
per nest attempt (n = 4,855 nests). Rodgers et al. (2009, p. 3) also
reported the St. Johns River basin production rate of 1.49
1.21 fledglings per nest attempt (n = 3,058 nests) and for successful
nests an average fledgling rate of 2.26 0.73 fledglings
per nest attempt (n = 2,105 nests) from 2004 to 2008.
Bryan and Robinette (2008, p. 20) reported rates of 2.3 and 1.6
fledged young per nesting attempt in 2004 and 2005, respectively, for
South Carolina and Georgia. The 2011, 2012, and 2013 productivity rates
for Georgia were 1.32, 1.13, and 0.67 (T. Keyes, Georgia DNR, pers.
comm., 2012 and 2013). During the data collection period of 1983-2012
in Georgia, the weighted average of all years and colonies was
1.760.8 (158 colony-years) with a range of 0.33 to 2.65 (T.
Keyes, Georgia DNR, pers. comm., 2013). Murphy and Coker (2008, p. 5)
reported that since the wood stork was listed in 1984, South Carolina
colonies averaged 2.08 young per successful nest with a range of 1.72
to 2.73. In 2011, South Carolina productivity was 1.6 fledged young per
nest at two colonies, 1.1 in 2012 at seven colonies monitored, and 1.4
in 2013 at nine colonies monitored (C. Hand, South Carolina DNR, pers.
comm., 2013).
The Palm Beach County Solid Waste Authority colony was documented
with 1.08, 0.46, and 0.52 fledgling per nesting attempt in 2011, 2012
and 2013, respectively (M. Morrison, PBC, pers. comm., 2013). The
Corkscrew Swamp Sanctuary colony near Naples, Florida (J. Lauritsen,
Audubon, pers. comm., 2012), documented no nesting in 2010-13, which
also coincides with years with drought conditions for this basin
(http://www.sfwmd.gov/portal/page/portal/xweb%20weather/rainfall%20historical%20%28year-to-date%29 for 2010-2012). Productivity
was 2.29 fledglings per nesting attempt in 2009, and annual rates
ranged from 0.00 (abandonment) to 2.55 (2001-2013). Cook (2011, p. 2)
reports that the 2011 productivity in the Everglades was relatively
low, that all 820 nests failed in 2012 (Cook 2012, p. 2). In 2013, wood
storks were largely successful in the Water Conservation Areas, Tamiami
West colony in the northern Everglades and lower in the southern
Everglades (Cook 2013, p. 2). The U.S. breeding population of the wood
stork's productivity data that have been collected using the method
developed by Rogders (2005) is available at: fws.gov/northflorida/wood
storks.
Habitat
Wood storks use a wide variety of freshwater and estuarine wetlands
for nesting, feeding, and roosting throughout their range and thus are
dependent upon a mosaic of wetlands for breeding and foraging. For
nesting, wood storks generally select patches of medium to tall trees
as nesting sites, which are located either in standing water such as
swamps, or on islands surrounded by relatively broad expanses of open
water (Ogden 1991, p. 43). Colony sites located in standing water must
remain inundated throughout the nesting cycle to protect against
predation and nest abandonment. Connectivity to the mainland is a
hazard to the colony longevity and persistence (Tsai et al. 2011, p.
5). A wood stork tends to use the same colony site over many years, as
long as the site remains undisturbed, and sufficient feeding habitat
remains in the surrounding wetlands (Frederick and Ogden 1997, p. 320).
Colony turnover is a typical and fairly rapid process for this species
(Frederick and Meyer 2008, p. 12). Wood storks may also abandon
traditional wetland sites if changes in water management result in
water loss from beneath the colony trees.
Typical foraging sites include a mosaic of shallow water wetlands.
Several factors affect the suitability of potential foraging habitat
for wood storks. Foraging habitats must provide both a sufficient
density and biomass of forage fish and other prey and have vegetation
characteristics that allow storks to locate and capture prey. Calm
water, about 5 to 40 cm (2 to 16 in) in depth, and free of dense
aquatic vegetation, is preferred (Coulter and Bryan 1993, p. 61).
During nesting, these areas must also be sufficiently close to the
colony to allow storks to deliver prey to nestlings efficiently.
Hydrologic and environmental characteristics have strong effects on
fish density, and these factors may be some of the most significant in
determining foraging habitat suitability. Important to wood stork
productivity is the timing of two different factors of wetland
hydrology. The production of prey that support a wood stork colony is
directly related to uninterrupted hydro periods of certain durations
prior to the nesting season and then prey becoming available due to
short-term drawdown of water levels that cue and support wood stork
nesting.
Alterations in the quality and amount of foraging habitats in the
Florida Everglades and extensive drainage and land conversions
throughout south Florida led to the initial decline of the wood stork
nesting population and the change in the timing and location of nesting
in response to the alterations in hydrology and habitat (Ogden 1994, p.
566). The overall distribution of the breeding population of wood
storks is in transition. The wood stork appears to have adapted to
changes in habitat in south Florida in part by nesting later, nesting
in colonies in the interior Everglades system (Ogden 1994, p. 566), and
by expanding its breeding range north into Georgia, South Carolina, and
North Carolina (Brooks and Dean 2008, p. 58). To date, many of the
colonies in the more northern range extension are much smaller than
historic colonies in south Florida and this may be the factor of a more
linear distribution of foraging habitats with wetlands associated with
rivers, inter-tidal wetlands, isolated
[[Page 37083]]
wetlands and marsh impoundments (Murphy and Coker 2008, p. 3).
Distribution
The wood stork occurs in South America from northern Argentina,
eastern Peru, and western Ecuador, north into Central America, Mexico,
Cuba, Hispaniola, and the southern United States. The breeding range
includes the southeastern United States in North America, Cuba and
Hispaniola in the Caribbean, and southern Mexico through Central
America (Figure 1). In South America, the breeding range is west of the
Andes south from Colombia to western Ecuador, east of the Andes from
Colombia south through the Amazonas in Brazil to eastern Peru, northern
Bolivia and northern Argentina east to the Atlantic coast through
Paraguay, Uruguay, and north to the Guianas and Venezuela (Figure 1;
Coulter et al. 1999, p. 2). The winter range in Central and South
America is not well studied, but wood storks are known to occur year-
round as a resident throughout the breeding range.
At the time of listing in 1984, the range of the U.S. population of
wood storks was Florida, Georgia, South Carolina, and Alabama. Breeding
was restricted primarily to 22 nesting colonies in peninsular Florida
in 1983 and only four colonies occurring in Georgia and South Carolina.
The current breeding range includes peninsular Florida (39-57 colonies
2010-2013), the coastal plain and large river systems of Georgia (17-28
colonies) and South Carolina (14-23 colonies), and southeastern North
Carolina (1-3 colonies). The breeding range has expanded west to south-
central Georgia and to the panhandle of Florida to the Apalachicola
River system. The nesting colony database for the U.S. breeding
population of the wood stork can be found at http://www.wec.ufl.edu/faculty/frederickp/woodstork/. The nonbreeding season range includes
all of Florida; the coastal plains and large river systems of Alabama,
Georgia, South Carolina; and southern North Carolina and eastern
Mississippi.
[[Page 37084]]
[GRAPHIC] [TIFF OMITTED] TR30JN14.000
Wood storks are not true migrants, but some individuals do undergo
lengthy inter-regional travel in response to resource availability
(Coulter et al. 1999, p. 3; Bryan et al. 2008, p. 39). Generally, wood
storks disperse following breeding. As the rainy season begins in May
in south Florida and the Everglades, post-breeding wood storks,
fledglings, and juveniles disperse throughout peninsular Florida and
many move northward along the coastlines and coastal plain of Georgia,
South Carolina, North Carolina and westward along large river basins in
Alabama and eastern Mississippi, while others do not disperse (Coulter
et al. 1999, p. 2; Hylton 2004, pp. 50-52; Bryan et al. 2008, pp. 39-
40). Individuals from northern Florida, Georgia, and South Carolina
colonies also disperse across the coastal plain and coastal marshes in
the southeastern United States in July to August after the breeding
season. Most wood storks in this population winter in south and central
Florida and along the coast of peninsular Florida, Georgia, and South
Carolina. These inter-regional movements have been documented through
color marking, banding, radio-telemetry and satellite-telemetry studies
(Comer et al. 1987, p. 165; Ogden 1996, p. 34; Coulter et al. 1999, p.
4; Savage et al. 1999, p. 65; Bryan et al. 2008, pp. 39-41).
[[Page 37085]]
Wood storks are seasonal visitors in Texas, Louisiana, the lower
Mississippi Valley, and California. These are post breeders and
juveniles from Central America (Rechnitzer 1956, p. 431; Coulter et al.
1999, pp. 4-5). Bryan et al. (2008, pp. 39-40) suggest that wood storks
observed in western Mississippi and Louisiana originate from Central
America, and wood storks found in eastern Mississippi originate from
the U.S. population. Behaviorally, wood storks are not predisposed to
travel across open waters like the Gulf of Mexico, as they use thermals
for soaring flight for long-distance movements. The lack of thermals
over open water restricts movements back and forth across the Gulf of
Mexico from Florida to Central and South America or the Caribbean.
Rangewide Status and Demographics
At the global level, the International Union for Conservation of
Nature (IUCN) classifies the wood stork as a species of ``least
concern.'' This is due to the apparent demographic stability documented
in its large range that encompasses portions of North, Central, and
South America (IUCN 2010, p. 1). Bryan and Borkhataria (2010, p. 2)
compiled and summarized the conservation status for wood storks in
Central and South America and provide the following description with
regard to the rangewide status of the wood stork:
The IUCN Red List/BirdLife International listing classifies the
wood stork as a species of ``least concern'' for its entire range
(BirdLife International 2008, 2009). This classification is based on
breeding/resident range size, population trends, population size.
This classification is due in part to an extremely large global
breeding range (estimated at 14,000,000 km\2\) and a moderately
small to large population estimate (38,000-130,000 birds). Although
the species' global population trend is thought to be decreasing,
the decline is not thought to be sufficiently rapid to reach
critical thresholds to threaten the species (BirdLife 2009: a
``vulnerable'' population exhibits a >30% decline over 10 years or
three generations). Population size estimates for South America
range from 50,000-100,000 wood storks (Byers et al. 1995) and
approximately 48,000-70,000 wood storks in Central and North America
(Kushlan et al. 2002).
Also, a recent assessment aimed at identifying the world's most
climate vulnerable species across many taxa included consideration of
the wood stock throughout its entire range in North, Central and South
America. The assessment concluded that the relative overall climate
change vulnerability of the wood stork is low (Foden et al. 2013,
Appendix A).
The U.S. wood stork population decline between 1930 and 1978 is
attributed to reduction in the food base necessary to support breeding
colonies, which is thought to have been related to loss of wetland
habitats and changes in hydroperiods (Ogden and Nesbitt 1979, p. 521;
Ogden and Patty 1981, p. 97; USFWS 1997, p. 10; Coulter et al. 1999, p.
18). The U.S. breeding population is considered regionally endangered
by IUCN due to habitat degradation (IUCN 2011). Ogden (1978, p. 143)
concluded the U.S. wood stork breeding population in the 1930s was
probably less than 100,000 individuals, or between 15,000 and 20,000
pairs. The estimated U.S. population of breeding wood storks throughout
the southeastern United States declined from 15,000-20,000, to about
10,000 pairs in 1960, to a low of 2,700-5,700 pairs between 1977 and
1980 (Ogden et al. 1987, p. 752). The low of 2,700 nesting pairs was
documented in 1978, during the severe drought when many wood storks
likely did not breed.
During the 29-year period since listing under the Act (1984 to
2013), 20 synoptic surveys of nesting colonies of the wood stork in the
U.S. population's breeding range (Florida, Georgia, South Carolina, and
North Carolina) were completed. Fourteen of those resulted in counts
exceeding 6,000 pairs. Ten of those higher counts occurred since 2002
(2002, 2003, 2004, 2006, 2008, 2009, 2010, 2011, 2012, and 2013; Table
1; USFWS 2013). Three counts of more than 10,000 pairs have occurred
during the past 8 years, and the count of 12,720 pairs in 2009 is the
highest on record since the early 1960s. This population estimate along
with a conservative estimate of 4,000 pre-breeding age birds suggest
30,000 storks were inhabiting the United States in 2009 (Bryan and
Borkhataria 2010, p. 2). Nest counts were 8,149 in 2010, 9,579 in 2011,
8,452 in 2012, and 11,046 in 2013 (Table 1).
The Service and its partners have used synoptic aerial surveys to
monitor the wood stork breeding population during the peak of the
nesting season (April) since the mid-1970s. The Service acknowledges
the limitations involved in relying on aerial surveys for developing
wood stork population estimates as they may underestimate numbers of
nests (Rodgers et al. 1995, p. 655). Frederick et al. (2003, p. 282)
found that accuracy of aerial counts of wading birds can be quite high
and Rodgers et al. (2005, p. 230) found that, by including ground
counts in the survey and surveying a large proportion of the nesting
colonies, the variability can be reduced. The Service notes that the
wood stork is a long-lived species that demonstrates considerable
variation in nesting population numbers in response to changing
hydrological conditions. This long reproductive lifespan allows wood
storks to tolerate reproductive failure in some years, and naturally
occurring events have undoubtedly always affected the breeding success
of this species, causing breeding failures and variability in annual
nesting (USFWS 1997, p. 11) and productivity.
Table 1--Wood Stork Nesting Data in the Southeastern United States [USFWS 2013]
--------------------------------------------------------------------------------------------------------------------------------------------------------
Total Florida Georgia South Carolina North Carolina
-------------------------------------------------------------------------------------------------------------
Year Nesting Nesting Nesting Nesting Nesting
pairs Colonies pairs Colonies pairs Colonies pairs Colonies pairs Colonies
--------------------------------------------------------------------------------------------------------------------------------------------------------
1975...................................... 9,752 27 9,610 24 142 3
1976...................................... 5,310 17 5,294 16 16 1
1977...................................... 5,263 25 5,125 21 138 4
1978...................................... 2,695 18 2,595 16 100 2
1979...................................... 4,648 24 3,800 22 55 2
1980...................................... 5,063 25 4,766 20 297 5
1981...................................... 4,442 22 4,156 19 275 2 11 1
1982...................................... 3,575 22 3,420 18 135 2 20 1
1983...................................... 5,983 25 5,600 22 363 2 20 1
1984...................................... 6,245 29 5,647 25 576 3 22 1
1985...................................... 5,193 23 4,562 30 557 5 74 1
1986...................................... ......... ......... (**) ......... 648 4 120 3
1987...................................... ......... ......... (**) ......... 506 5 194 3
[[Page 37086]]
1988...................................... ......... ......... (**) ......... 311 4 179 3
1989...................................... ......... ......... (**) ......... 543 6 376 3
1990...................................... ......... ......... (**) ......... 709 10 536 6
1991...................................... 4,073 37 2,440 25 969 9 664 3
1992...................................... ......... ......... (**) ......... 1,091 9 475 3
1993...................................... 6,729 43 4,262 29 1,661 11 806 3
1994...................................... 5,768 47 3,588 26 1,468 14 712 7
1995...................................... 7,853 54 5,523 31 1,501 17 829 6
1996...................................... ......... ......... (**) ......... 1,480 18 953 7
1997...................................... ......... ......... (**) ......... 1,379 15 917 8
1998...................................... ......... ......... (**) ......... 1,665 15 1,093 10
1999...................................... 7,768 71 6,109 51 1,139 13 520 8
2000...................................... ......... ......... (**) ......... 566 7 1,236 11
2001...................................... 5,582 44 3,246 23 1,162 12 1,174 9
2002...................................... 7,855 70 5,463 46 1,256 14 1,136 10
2003...................................... 8,813 78 5,804 49 1,653 18 1,356 11
2004...................................... 8,379 93 4,726 63 1,596 17 2,057 13
2005...................................... 5,572 73 2,304 40 1,817 19 1,419 13 32 1
2006...................................... 11,279 82 7,216 48 1,928 21 2,010 13 125 1
2007...................................... 4,406 55 1,553 25 1,054 15 1,607 14 192 1
2008...................................... 6,118 73 1,838 31 2,292 25 1,839 16 149 1
2009...................................... 12,720 86 9,428 54 1,676 19 1,482 12 134 1
2010...................................... 8,149 94 3,828 51 2,708 28 1,393 14 220 1
2011...................................... 9,579 88 5,292 45 2,160 19 2,031 23 96 1
2012...................................... 8,452 77 4,539 39 1,905 17 1,827 19 181 2
2013...................................... 11,046 100 6,948 57 1,873 19 2,020 21 205 3
--------------------------------------------------------------------------------------------------------------------------------------------------------
** No survey data available for North and Central Florida.
Previous Federal Actions
For more information on previous Federal actions, refer to the 12-
month finding and proposed rule to reclassify the U.S. breeding
population of the wood stork (77 FR 75947).
Distinct Vertebrate Population Segment Analysis
On February 7, 1996, we published in the Federal Register our
``Policy Regarding the Recognition of Distinct Vertebrate Population
Segments under the Endangered Species Act'' (DPS Policy) (61 FR 4722).
For a population to be listed under the Act as a distinct vertebrate
population segment, three elements are considered: (1) The discreteness
of the population segment in relation to the remainder of the species
to which it belongs; (2) the significance of the population segment to
the species to which it belongs; and (3) the population segment's
conservation status in relation to the Act's standards for listing,
(i.e., is the population segment, when treated as if it were a species,
endangered or threatened). The Act defines ``species'' to include ``. .
. any distinct population segment of any species of vertebrate fish or
wildlife which interbreeds when mature'' (16 U.S.C. 1532(16)). The best
available scientific information supports recognition of the U.S.
breeding population of the wood stork as a distinct vertebrate
population segment. We discuss the discreteness and significance of the
population segment within this section; the remainder of the document
discusses the status of the U.S. wood stork DPS.
Discreteness
The DPS policy states that a population segment of a vertebrate
species may be considered discrete if it satisfies either one of the
following conditions:
(1) It is markedly separated from other populations of the same
taxon as a consequence of physical, physiological, ecological, or
behavioral factors. Quantitative measures of genetic or morphological
discontinuity may provide evidence of this separation; or
(2) It is delimited by international governmental boundaries
between which significant differences exist in control of exploitation,
management of habitat, conservation status, or regulatory mechanisms
that are significant in light of section 4(a)(1)(D) of the Act.
Globally, wood storks occur only in the Western Hemisphere and
comprise a mosaic of breeding populations in North, Central, and South
America, and the Caribbean, each with unique nesting sites, foraging
areas, and seasonal movement patterns in response to regional
environmental factors. Historically, wood storks nested in all Atlantic
and Gulf coastal United States from Texas to South Carolina (Bent 1926,
p. 65; Cone and Hall 1970, p. 14; Dusi and Dusi 1968, p. 14; Howell
1932, pp. 113-115; Oberholser 1938, p. 76; Oberholser and Kincaid 1974,
p. 124; Wayne 1910), although the colonies outside Florida formed
irregularly and contained few birds (Ogden and Nesbitt 1979, p. 512).
Currently, the range of the U.S. breeding population includes
Alabama, Florida, Georgia, Mississippi, North Carolina, and South
Carolina, with breeding and nesting documented in Florida, Georgia,
North Carolina, and South Carolina. The U.S. wood stork population
represents the northernmost extent of the wood stork's range and the
only population breeding in the United States (USFWS 1997, p. 1;
Coulter et al. 1999, pp. 2-3). The U.S. population's breeding range is
separated by the Strait of Florida from the next nearest nesting
population, which is located in Cuba, 151 km (94 mi) away; it is
approximately 965 km (600 mi) over the Gulf of Mexico from the other
North American nesting colony, which breeds in southern Mexico.
However, wood storks are not behaviorally predisposed to travel across
the open ocean. Wood storks use thermals for soaring flight for
[[Page 37087]]
long-distance movements. The lack of thermals over water may restrict
movements from Florida to the Caribbean or to Mexico and Central and
South America (Coulter et al. 1999, p. 4). The available evidence does
not suggest that wood storks have crossed the Florida Straits between
the Caribbean islands and the United States or crossed the Gulf of
Mexico to or from Central and South America.
Lengthy inter- and intra-regional movements, related to food
availability, to the wetlands of the Mississippi River Basin and
adjacent coastal plain river basins have been documented from both the
U.S. population and Central American wood storks (Coulter et al. 1999,
p. 5; Bryan et al. 2008, pp. 40-41). These studies suggest post-
breeding dispersal occurs along the coastal plain, not across the Gulf
of Mexico, and that wood storks observed in eastern Mississippi
originate from the southeastern United States and those observed in
western Mississippi and Louisiana originate from Central America. A
small percentage of wood storks from both the United States and Central
America apparently overlap during this post-breeding season dispersal
within Mississippi. Some small but unknown level of mixing may occur
between U.S. and Central American breeding populations in Mississippi
(Bryan et al. 2008, pp. 40-41; R. Borkhataria, University of Florida,
pers. comm., 2010). However, based upon satellite-telemetry studies
(e.g., Hylton 2004, pp. 50-52; Bryan et al. 2008, pp. 39-40;
Borkhataria 2009, pp. 120-124) and other marking studies, mixing
appears negligible. Based on the above information, if the U.S.
population were extirpated, it is our assessment that repopulation from
the Central American wood storks would not be sufficient to replenish
the depleted population in the foreseeable future.
Genetic data support the conclusion that wood storks occurring in
the southeastern United States function as one population. Stangel et
al. (1990, p. 15) employed starch gel electrophoretic techniques to
examine genetic variation in Florida wood stork colonies. The study did
not indicate significant allozyme differences within or between
colonies. Van Den Bussche et al. (1999, p. 1083) used a combination of
DNA or allozyme approaches and found low levels of genetic variability
and allelic diversity within Georgia and Florida colonies, suggesting
one population of wood storks in the southeastern United States. A
genetic comparison using mitochondrial DNA (mtDNA) between U.S. and
Brazilian wood storks (the north and south ends of the geographic
range) reveals that either a demographic decline or a recent
evolutionary bottleneck reduced the levels of mtDNA variability of the
U.S. population (Lopes et al. 2011, p. 1911). The genetic structuring
assessment revealed no significant differentiation between the U.S. and
Brazilian wood storks, indicating that either the populations were only
recently separated or that gene flow continues to occur at low levels,
and the haplotype network analysis indicated low levels of gene flow
between populations that were closely related in the past (Lopes et al.
2011, p. 1911). Genetic studies indicate no significant differences
between U.S. and Brazilian wood storks. However, satellite-tracked
movements of U.S. and Central American wood storks indicate that U.S.
and Brazilian birds likely do not interbreed (Hylton 2004, pp. 50-52;
Bryan et al. 2008, pp. 39-40; Borkhataria 2009, pp. 120-124). Based on
the genetic information, we conclude that a past demographic decline
has led to the reduced levels of genetic variability in all populations
of wood stork that were studied, that U.S. and other populations were
only recently separated, that the southeastern U.S. populations act as
a single population, and negligible or very low gene flow occurs
between the populations in the United States and Brazil.
Consequently, we conclude, based on the best available information,
that the U.S. breeding population of the wood stork is markedly
separated from wood stork populations in the Caribbean, Mexico, Central
America, and South America based on physical separation and wood stork
dispersal behavior.
Significance
The DPS policy states that populations that are found to be
discrete will then be examined for their biological or ecological
significance to the taxon to which they belong. This consideration may
include evidence that the loss of the population would create a
significant gap in the range of the taxon. The U.S. breeding population
of the wood stork represents the northernmost portion of the species'
range in the world (Coulter et al. 1999, p. 2) and the only population
breeding in the United States. Loss of this population would result in
a significant gap in the extent of the species' range. Because the
nearest populations in the Caribbean and North America would not likely
be able to naturally repopulate the U.S. breeding population if it were
extirpated, wood storks would no longer breed in the Everglades and in
the salt- and fresh-water wetlands of Florida, Georgia, South Carolina,
and North Carolina. Maintaining a species throughout its historical and
current range helps ensure the species' population viability and reduce
impacts to the species as a whole due to localized stochastic events.
Therefore, we find that loss of the U.S. breeding population of the
wood stork, whose range has expanded to include Mississippi and North
Carolina (USFWS 2007, p. 11), would constitute a significant gap in the
range of the species as a whole.
Summary
Based on the above analysis, we conclude that the U.S. breeding
population of wood storks meets both the discreteness and significance
elements of the 1996 DPS policy. Therefore, we recognize this
population as a valid DPS.
Recovery Plan
Section 4(f) of the Act directs us to develop and implement
recovery plans for the conservation and survival of endangered and
threatened species unless we determine that such a plan will not
promote the conservation of the species. The Act directs that, to the
maximum extent practicable, we incorporate into each plan:
(1) Site-specific management actions as may be necessary to achieve
the plan's goals for conservation and survival of the species;
(2) Objective, measurable criteria which, when met, would result in
a determination in accordance with the provisions of section 4 of the
Act, that the species be removed from the Federal List of Endangered
and Threatened Wildlife and Plants (List); and
(3) Estimates of the time required and cost to carry out the plan's
goal and to achieve intermediate steps toward that goal.
Recovery plans are intended to provide guidance to the Service,
States, and other partners on methods of eliminating or ameliorating
threats to listed species and on criteria that may be used to determine
when recovery is achieved. However, recovery plans are not regulatory
documents and cannot substitute for the determinations and promulgation
of regulations required under section 4(a)(1). Determinations to
reclassify a species on the list made under section 4(a)(1) must be
based on the best scientific and commercial data available at the time
of the determination, regardless of whether these data differ from the
recovery plan. They must reflect determinations made in accordance with
sections 4(a)(1) and 4(b) of the Act. Specifically, section
[[Page 37088]]
4(a)(1) requires that the Secretary determine whether a species is
endangered or threatened (or not) because of one or more of five threat
factors. Section 4(b) requires the determination made under section
4(a)(1) as to whether a species is endangered or threatened because of
one or more of the five factors be based on the best scientific and
commercial data available.
In the course of implementing conservation actions for a species,
new information is often gained that requires recovery efforts to be
modified accordingly. There are many paths to accomplishing recovery of
a species, and recovery may be achieved without all criteria being
fully met. For example, one or more criteria may have been exceeded
while other criteria may not have been accomplished, yet the Service
may judge that, overall, the threats have been minimized sufficiently
or are not of sufficient imminence, intensity, or magnitude, and the
species is robust enough, to reclassify the species from endangered to
threatened. In other cases, recovery opportunities may have been
recognized that were not known at the time the recovery plan was
finalized. These opportunities may be used instead of methods
identified in the recovery plan.
Likewise, information on the species may be learned that was not
known at the time the recovery plan was finalized. The new information
may change the extent that criteria need to be met for recognizing
recovery of the species. Overall, recovery of the species is a dynamic
process requiring adaptive management, planning, implementing, and
evaluating the degree of recovery of a species that may, or may not,
fully follow the guidance provided in a recovery plan.
Thus, while the recovery plan provides important guidance on the
direction and strategy for recovery and indicates when a rulemaking
process may be initiated, the determination to reclassify a species on
the Federal List is ultimately based on an analysis of whether the
species is endangered or threatened, as defined by the Act. The
following discussion provides a brief review of the recovery planning
for wood storks, as well as an analysis of the recovery objectives and
criteria as they relate to evaluating the status of the species.
We published the original recovery plan for the U.S. breeding
population of wood stork on September 9, 1986, and revised it on
January 27, 1997 (USFWS 1997). The recovery plan includes
reclassification criteria and delisting criteria: The recovery criteria
for the U.S. breeding population DPS of wood storks state that
reclassification from endangered to threatened could be considered when
there are 6,000 nesting pairs and annual average regional productivity
is greater than 1.5 chicks per nest per year (both calculated over a 3-
year average). Delisting could be considered when there are 10,000
nesting pairs (50 percent of historical population), and annual
regional productivity greater than 1.5 chicks per nest per year (both
calculated over a 5-year average from the time of reclassification). As
a subset of the 10,000 pairs, a minimum of 2,500 successful nesting
pairs must occur in the Everglades and Big Cypress systems and 3,500 in
the South Florida Ecosystem as defined by the South Florida Multi-
Species Recovery Plan (USFWS 1999, p. 4-417).
Recovery Actions
The recovery plan identifies four primary recovery actions for the
U.S. breeding population of the wood stork: (1) Protect currently
occupied habitat, (2) restore and enhance habitat, (3) conduct applied
research necessary to accomplish recovery goals, and (4) increase
public awareness. These primary recovery actions have been initiated.
Many of the actions listed under these categories are of high priority
to implement and are ongoing.
Recovery Task (1): Protect currently occupied habitat. At a
minimum, for continued survival of the U.S. breeding population,
currently occupied nesting, roosting, and foraging habitat must be
protected from further loss or degradation. Watersheds supporting
natural nesting habitat should remain unaltered, or be restored to
function as a natural system if previously altered. Recovery actions
under this recovery task include: (1.1) Locate important habitat, (1.2)
prioritize habitat, (1.3) work with private landowners to protect
habitat, (1.4) acquire land, (1.5) protect sites from disturbance, and
(1.6) use existing regulatory mechanisms to protect habitat.
Recent habitat models (e.g., Gawlik 2002; Herring 2007; Borkhataria
2009; Rodgers et al. 2010; Borkhataria et al. 2012); ongoing annual
monitoring of nesting colonies (e.g., Cook and Koboza 2012; Brooks and
Dean 2008; Murphy and Coker 2008; Winn et al. 2008; Frederick and Meyer
2008); surveys of nesting colony core foraging areas in Florida,
Georgia, and South Carolina (e.g., Herring 2007; Bryan and Stephens
2007; Lauritsen 2010; Tomlinson 2009; Meyer 2010); and satellite-
telemetry studies (e.g., Hylton 2004; Hylton et al. 2006; Bryan et al.
2008; Borkhataria 2009; Lauritsen 2010; Borkhataria et al. 2012) are
helping to update conservation information and tools that are used to
identify, prioritize, protect, restore, and acquire important wood
stork habitats. Core foraging areas near large colonies on protected
lands, like Corkscrew Swamp Sanctuary in Florida, Harris Neck National
Wildlife Refuge in Georgia, and Washo Reserve in South Carolina, have
been identified. However, alteration and loss of foraging habitat
continues as a threat to recovery, as such habitat continues to be lost
today through the continual expansion of the human environment,
resulting in new development and associated roads and other
infrastructure. The Service has developed a brochure, Wood Stork
Conservation and Management for Land Owners, to assist public and
private land managers in protecting and restoring wood stork habitat
(USFWS 2001). The Wood Stork Habitat Management Guidelines (Ogden 1990)
have also been updated (Bryan 2006) and are an important conservation
tool to provide guidance on protecting wood storks and their habitats.
In an effort to minimize loss of wetland habitats important to wood
stork recovery, like those within the core foraging area of a nesting
colony, the Service's South and North Florida Ecological Services Field
Offices have also developed a ``May Affect'' key to assist regulators
with review of wetland dredge and fill permit applications.
Lands being purchased for conservation through Federal, State and
private acquisition programs also contribute to wood stork recovery.
Florida Forever is the largest State public land acquisition program of
its kind in the United States with approximately 9.9 million acres
managed for conservation in Florida; more than 2.5 million acres were
purchased under the Florida Forever and Preservation 2000 programs
(http://www.dep.state.fl.us/lands/fl_forever.htm). Listed species,
wetlands quality, and other attributes that affect wood storks are
considered in the ranking criteria for lands purchased in these
programs. Southeastern U.S. State natural resource agency acquisition
programs include: Florida Forever; Georgia Land Conservation Program;
South Carolina Land Legacy and Conservation Bank Act; North Carolina
Natural Heritage Trust Fund, Parks and Recreation Trust Fund, Clean
Water Management Trust Fund, Agricultural Development and Farmland
Preservation Trust Fund; Alabama Forever Wild Trust Fund; and
Mississippi Wildlife Heritage Fund. The
[[Page 37089]]
purpose of these programs is to preserve statewide networks of land and
water resources by providing land conservation funding options that may
include grants, low interest loans, and tax incentives which augment
other private, local, State, and Federal funding sources to achieve the
permanent conservation of land through the acquisition of conservation
easements and fee simple ownership.
Consistent with the recent adoption of the Department of the
Interior policy on climate change adaptation (523 DM 1; http://elips.doi.gov/elips/0/doc/3741/Page1.aspx) and a similar policy by the
Service (056 FW 1; http://www.fws.gov/policy/056fw1.html), we will
evaluate and address the impacts of climate change in our planning and
decision making, as appropriate. Also, the Landscape Conservation
Cooperative (LCC) initiative will likely provide information that
informs wood stork recovery through landscape-level conservation
strategies to restore, manage, and conserve the biodiversity of the
region in the face of both climate change and intense development
pressure associated with a rapidly growing human population. Ongoing
and forthcoming efforts at State, county, and other local levels
related to climate change adaptation also are likely to inform how we
revise and implement the recovery plan for the wood stork. Future
updates to the recovery plan will consider and include emerging
information such as on-going and projected change in climate and
related effects on wood stork habitat and will help to guide future
recovery efforts.
Recovery Task (2): Restore and enhance habitat. A prerequisite for
recovery of the wood stork in the southeastern United States is the
restoration and enhancement of suitable habitat throughout the mosaic
of habitat types used by this species. Recovery actions include: (2.1)
Restore the Everglades and Big Cypress systems, (2.2) enhance nesting
and roosting sites throughout the range, and (2.3) enhance foraging
habitat by modifying hydrologic regimes in existing artificial
impoundments to maximize use by wood storks.
Wood storks depend upon a mosaic of wetlands throughout the coastal
plain of the southeastern United States for breeding and foraging.
Ecosystems and wetlands are being restored throughout the southeastern
United States through programs such as the Comprehensive Everglades
Restoration Program (CERP) (RECOVER 2009); Kissimmee River Restoration
Project, which includes a goal to restore over 40 square miles of river
and floodplain ecosystem including 43 miles of meandering river channel
and 27,000 acres of wetlands (USACE 2011); and Upper St. Johns Basin
Restoration Project, which has enhanced and restored 150,000 acres of
marsh (SJRWMD 2011). These and other large-scale wetland restoration
projects are significantly contributing to wood stork recovery by
reducing the threat of habitat loss. Research by Tsai et al. (2011, p.
5) provides recommendations for enhancing nesting habitat and concludes
that management and conservation priority should be given to colonies
that are large, have been in existence for more than 10 years, and are
located on islands rather than mainland shorelines. Management actions
that can enhance the isolation of colonies from the mainland apparently
are very effective as colonies on true islands are less likely to be
extirpated and are much more likely to be colonized than those that
have partial or complete connection with the mainland (Tsai et al.
2011, p. 5). These recommendations will inform efforts to update
recovery actions and initiatives.
Management plans such as State wildlife action plans (http://www.wildlifeactionplans.org/) help to identify important habitats on
which to focus conservation efforts. Other management plans such as the
North American Waterbird Conservation Plan (2002) and the North
American Waterfowl Management Plan (USFWS 2011) also help to identify
focus areas for conservation. By highlighting important habitats or
areas, such as the ACE Basin and Winyah Bay in South Carolina, funds
and conservation initiatives are directed towards restoring these
important habitat areas and contribute to recovery by reducing the
threat due to loss of habitat. Thousands of acres are being protected,
enhanced, restored, and brought under conservation easements to assist
in wildlife conservation through programs such as the Wetland Reserve
Program (WRP) and the Farm Bill, including 70,000 acres of wetlands in
Alabama, Florida, Georgia, Mississippi, North Carolina, and South
Carolina in 2010 (NRCS 2011). The WRP is a voluntary program offering
landowners the opportunity to protect, restore, and enhance wetlands on
their property.
The U.S. Department of Agriculture, Natural Resources Conservation
Service (NRCS) provides technical and financial support to help
landowners with their wetland restoration efforts. The goal of the NRCS
is to achieve the greatest wetland functions and values, along with
optimum wildlife habitat, on every acre enrolled in the program. This
program offers landowners an opportunity to establish long-term
conservation and wildlife practices and protection and, therefore,
provides some benefits to wood stork recovery. In Florida, the WRP
program has restored over 200,000 acres of wetlands (Simpkins, Service,
pers. comm., 2011) and more than 115,000 acres in Alabama, Georgia, and
South Carolina. A majority of the Florida WRP-restored acres have been
within the Everglades and Big Cypress systems. A 2006 WRP restoration
of 200 acres of farmland in Camilla, Georgia, now supports the newest
Georgia wood stork colony, with over 100 nesting pairs annually. This
task will be complete once viable nesting occurs throughout the range
of this DPS. The most significant wetland restoration goal for wood
storks is to recover viable nesting subpopulations in the traditional
Everglades and Big Cypress nesting areas, including Corkscrew Swamp
Sanctuary, as outlined by CERP. Overall, future wetland restoration
efforts in the southeast United States will be beneficial to wood stork
recovery.
Future updates to the recovery plan will consider emerging
information on climate change and possible effects on wood stork
habitat restorations and enhancements and will help to guide future
recovery efforts.
Recovery Task (3): Conduct applied research necessary to accomplish
recovery goals. Recovery efforts for the wood stork will be more
effective with a better understanding of population biology, movement
patterns of U.S. and neighboring populations of wood storks, foraging
ecology and behavior, the importance of roost sites, and the possible
impacts of contaminants. Recovery actions include: (3.1) Determine
movement patterns of U.S. and neighboring populations of wood storks,
(3.2) determine population genetics, (3.3) monitor productivity of
stork populations, (3.4) monitor survivorship of stork populations,
(3.5) determine extent of competition/cooperation between wood storks
and other wading birds in mixed nesting colonies, (3.6) determine
foraging ecology and behavior, (3.7) determine the importance of roost
sites, and (3.8) determine the impacts of contaminants on wood stork
populations. The following is a summary of several recent monitoring
and research findings.
The South Florida Wading Bird Report (1996-2012) annually reports
on habitat monitoring and research with respect to the CERP and
foraging and nest monitoring projects for wood storks and wading birds
utilizing the Everglades and Big Cypress systems. This report provides
an annual
[[Page 37090]]
assessment on the Restoration Coordination and Verification Program
(RECOVER), the system-wide science arm of the CERP. Per Recovery Action
3.1 and 3.6, satellite-telemetry studies are providing new insight into
movement patterns (e.g., Hylton 2004; Bryan et al. 2008; Borkhataria
2009; Lauritsen 2010). Surveys to determine foraging distances from
nesting colonies and satellite-telemetry research are helping to update
our understanding of wood stork foraging ecology and of core foraging
areas (e.g., Herring 2007; Bryan and Stephens 2007; Borkhataria 2009;
Borkhataria et al. 2012; Meyers 2010; Lauritsen 2010; Tomlinson 2009).
Satellite-telemetry data and initiation of additional banding studies
are helping to refine survival estimates (Borkhataria 2009, pp. 63-64)
for population modeling (Borkhataria 2009) as identified under Recovery
Action 3.4. This population viability analysis demonstrated that,
despite the recent population growth, the south Florida portion of the
population could decline to a level that cannot be reversed even if
some individuals remain in the coming 50-year period (Borkhataria 2009,
p. 15).
Recent and ongoing systematic reconnaissance flights of the
Everglades, Kissimmee River, water conservation areas, Big Cypress
National Preserve, and Upper St. Johns River are monitoring wood stork
abundance and distribution in south Florida (Cheek 2012, pp. 23-26;
Alvarado 2012, pp. 32-42; Nelson 2010, p. 40; D. Hall, SJRWMD, pers.
comm., 2008). Annual synoptic nesting colony surveys help to monitor
the status of the breeding population. Per Recovery Action 3.3, recent
productivity research and monitoring efforts have documented
productivity rates to be similar to rates documented between the 1970s
and 1990s (Rodgers et al. 2008; Bryan and Robinette 2008). Rodgers et
al. (2008, p. 25) recommends developing an unbiased estimator of
productivity that takes into consideration the lack of nesting during
some years to more accurately estimate wood stork productivity at the
regional level.
A prime example of how research can influence management for wood
stork recovery is Borkhataria et al. (2012). This research documented
the effects of water management on juvenile stork survival in south
Florida and confirms the CERP goal of returning Everglades wood stork
nest initiation to an earlier time frame so that chicks are fledging
prior to the summer rainy season. To be successful reproductively, wood
storks in south Florida require prey be available during the nesting
season, with particularly high energy demands when chicks are growing
and fledging (Frederick et al. 2008, p. 3). This typically happens
during the winter/spring dry season in south Florida when water levels
recede most reliably.
A genetic structuring and haplotype network analysis comparison
indicates that either a demographic decline or a recent evolutionary
bottleneck reduced the levels of genetic variability in the U.S.
population (Lopes et al. 2011, p. 1911). The genetic structuring
assessment revealed no significant differentiation, indicating that
U.S. and Brazilian wood stork populations were only recently separated
or that gene flow between these populations continues to occur at low
levels. The haplotype network analysis indicated low current levels of
gene flow between populations that were closely related in the past
(Lopes et al. 2011, p. 1911).
Recovery Task (4): Increase public awareness. Wood storks utilize a
wide variety of wetland habitats. They are visually unique and generate
interest from the public. These factors have made the wood stork the
subject of many environmental education materials and programs. Many
brochures, videos, and educational packets are available. Recovery
actions include: (4.1) Increase awareness and appreciation through
educational materials, and (4.2) provide opportunities for the public
to view wood storks in captivity.
Examples of such wood stork educational efforts to increase public
awareness can be found on our Web site (http://www.fws.gov/northflorida/WoodStorks/wood-storks.htm) and the Web sites of many of
our recovery partners, including the Everglades National Park (http://www.nps.gov/ever/naturescience/woodstork.htm), Florida Fish and
Wildlife Conservation Commission (http://myfwc.com/research/wildlife/birds/wood-storks/), Georgia Department of Natural Resources (http://www.georgiawildlife.com/sites/default/files/uploads/wildlife/nongame/pdf/accounts/birds/mycteria_americana.pdf), South Carolina Department
of Natural Resources (http://www.dnr.sc.gov/cwcs/pdf/Woodstork.pdf),
University of Florida (http://www.wec.ufl.edu/faculty/frederickp/woodstork/), Audubon Society (http://birds.audubon.org/species/woosto),
Corkscrew Sanctuary Swamp (http://www.corkscrewsanctuary.org/Wildlife/Birds/profiles/wost.pdf), and others.
Opportunities for the public to view wood storks in the wild
include almost all National Wildlife Refuges (NWR) and National Parks
and Preserves in Florida and coastal Georgia and South Carolina,
including the Everglades National Park, Ten Thousand Island NWR, J.N.
Ding Darling NWR, Loxahatchee NWR, Pelican Island NWR, Merritt Island
NWR, Harris Neck NWR, and ACE Basin NWR. Several wood stork nesting
colonies can also be seen at public observation areas that do not
disturb the colony, such as Audubon's Corkscrew Swamp Sanctuary,
Parotis Pond in Everglades National Park, Pelican Island NWR, St.
Augustine Alligator Farm, Jacksonville Zoo and Gardens, and Harris Neck
NWR.
Recovery Achieved
The recovery criteria for the U.S. breeding population DPS of wood
storks state that reclassification from endangered to threatened could
be considered when there are 6,000 nesting pairs and annual average
regional productivity is greater than 1.5 chicks per nest per year
(both calculated over a 3-year average). Although variable,
productivity appears to be sufficient to support continued population
growth as evidenced by the increasing nesting population and range
expansion.
1. Nesting pairs. The U.S. breeding population of the wood stork
has been increasing since it was listed in 1984 (Brooks and Dean 2008,
p. 58; Borkhataria 2009, p. 34). Regional synoptic nesting surveys to
census wood stork colonies have been continuous in south Florida and
Georgia since 1976 and in South Carolina since 1981. Nest censuses of
the entire breeding range were conducted in 1975-1986, 1991, 1993-1995,
1997, 1999, and 2001-2013 (Table 1) with a census of almost every
active colony. The 3-year average for nesting pairs has exceeded the
reclassification criterion of 6,000 every year since 2003 (Table 2).
However, the nesting pair average is well below the 5-year average of
10,000 nesting pairs (a benchmark for delisting), and the 5-year
averages for nesting in the Everglades and Big Cypress Systems are
below 2,500 nesting pairs (another benchmark for delisting), as nesting
in south Florida remains variable (Table 2).
[[Page 37091]]
Table 2--Wood Stork Nesting Data in the Southeastern United States and 3-Year Averages (USFWS 2013). South Florida Includes Wood Stork Nesting in the
Following Florida Counties: Broward, Collier, Hendry, Lee, Martin, Miami-Dade, Monroe, and Palm Beach
--------------------------------------------------------------------------------------------------------------------------------------------------------
Total South FL Central/North FL GA SC NC
-----------------------------------------------------------------------------------------------------------------------
Year Nesting Nesting Nesting Nesting Nesting Nesting
pairs 3-yr avg pairs 3-yr avg pairs 3-yr avg pairs 3-yr avg pairs 3-yr avg pairs 3-yr avg
--------------------------------------------------------------------------------------------------------------------------------------------------------
1981............................ 4,442 ........ 2,428 ........ 1,728 ........ 275 ........ 11
1982............................ 3,575 ........ 1,237 ........ 2,183 ........ 135 ........ 20
1983............................ 5,983 4,667 2,858 2,174 2,742 2,218 363 258 20 17
1984............................ 6,245 5,268 1,245 1,780 4,402 3,109 576 358 22 21
1985............................ 5,193 5,807 798 1,634 3,764 3,636 557 499 74 39
1986............................ ........ ........ 643 895 ........ ........ 648 584 120 72
1987............................ ........ ........ 100 514 ........ ........ 506 570 194 129
1988............................ ........ ........ 755 499 ........ ........ 311 488 179 164
1989............................ ........ ........ 515 457 ........ ........ 543 453 376 250
1990............................ ........ ........ 475 582 ........ ........ 709 521 536 364
1991............................ 4,073 ........ 550 513 1,890 ........ 969 740 664 525
1992............................ ........ ........ 1,917 981 ........ ........ 1,091 923 475 558
1993............................ 6,729 ........ 587 1,018 3,675 ........ 1,661 1,240 806 648
1994............................ 5,768 ........ 741 1,082 2,847 ........ 1,468 1,407 712 664
1995............................ 7,853 6,783 1,140 823 4,383 3,635 1,501 1,543 829 782
1996............................ ........ ........ 1,215 1,032 ........ ........ 1,480 1,483 953 831
1997............................ ........ ........ 445 933 ........ ........ 1,379 1,453 917 900
1998............................ ........ ........ 478 713 ........ ........ 1,665 1,508 1,093 988
1999............................ ........ ........ 2,674 1,190 ........ ........ 1,139 1,394 520 843
2000............................ ........ ........ 3,996 2,383 ........ ........ 566 1,123 1,236 950
2001............................ 5,582 ........ 2,888 3,186 358 ........ 1,162 956 1,174 977
2002............................ 7,855 ........ 3,463 3,449 2,000 ........ 1,256 995 1,136 1,182
2003............................ 8,813 7,417 1,747 2,699 4,057 2,138 1,653 1,357 1,356 1,222
2004............................ 8,379 8,349 1,485 2,232 3,241 3,099 1,596 1,502 2,057 1,516
2005............................ 5,572 7,588 591 1,274 1,713 3,004 1,817 1,689 1,419 1,611 32
2006............................ 11,279 8,410 2,648 1,575 4,568 3,174 1,928 1,780 2,010 1,829 125
2007............................ 4,406 7,086 696 1,312 857 2,379 1,054 1,600 1,607 1,679 192 116
2008............................ 6,118 7,268 344 1,229 1,494 2,306 2,292 1,758 1,839 1,819 149 155
2009............................ 12,720 7,748 5,816 2,285 3,612 1,988 1,676 1,674 1,482 1,643 134 158
2010............................ 8,141 8,993 1,220 2,460 2,600 2,571 2,708 2,225 1,393 1,571 220 168
2011............................ 9,579 10,147 2,131 3,056 3,161 3,124 2,160 2,181 2,031 1,635 96 141
2012............................ 8,452 8,620 1,234 1,528 3,305 3,137 1,905 2,258 1,827 1,750 181 166
2013............................ 11,046 9,692 3,059 2,141 3,889 3,452 1,873 1,979 2,020 1,959 205 161
--------------------------------------------------------------------------------------------------------------------------------------------------------
2. Productivity. Researchers need to systematically determine
reproductive success (number of fledged young per nest and number of
fledged young per successful nest) for a majority of the colonies in
the same year(s) to better estimate productivity of the breeding
population (USFWS 1997, p. 24). Since nesting success often exhibits a
significant negative trend with hatching date (Rodgers and Schwikert
1997, p. 85), the entire nesting season must be sampled to avoid
biasing reproductive success data based on a few visits (Rodgers 2005,
p. 1). The Service acknowledges that the productivity dataset is
incomplete, with less than 25 percent of the colonies surveyed for
productivity during recent years and 50 percent surveyed between 2003
and 2007. During this time period, Brooks and Dean (2008, p. 56)
indicate the average productivity rate for all colonies monitored in
the southeastern United States was 1.2 chick/nest attempt between 2003
and 2005; 1.5 chick/nest attempt between 2004 and 2006; and 1.5 chick/
nest attempt between 2003 and 2006 (Brooks and Dean 2008, p. 56). Due
to funding and manpower constraints, rangewide, statewide, and regional
monitoring of wood stork productivity only has occurred episodically
(e.g., early 1980s and 2000s). As 80 to 90 wood stork colonies are now
active annually, Rodgers et al. (2008, p. 32) identifies that there is
a need to develop a long-term program of monitoring that relies on
monitoring of fewer colonies. The following are summaries of recent
productivity monitoring in Florida, Georgia, and South Carolina. The
full productivity data set can be viewed at: http://www.fws.gov/northflorida/WoodStorks/wood-storks.htm.
Florida: Rodgers et al. (2008, p. 25) reported a combined
production rate for 21 north- and central-Florida colonies from 2003 to
2005 of 1.19+0.09 fledglings per nest attempt (n = 4,855 nests).
Rodgers et al. (2009, p. 3) reported the St. Johns River basin
production rate of 1.49+1.21 fledglings per nest attempt (n = 3,058
nests) and, for successful nests, an average fledgling rate of
2.26+0.73 fledglings per nest attempt (n = 2,105 nests) from 2004 to
2008. The Jacksonville Zoological Gardens and Disney Wilderness
Preserve colonies report productivity rates of 2.0 and 0.5,
respectively, in 2011 and 2.2 and 0.8 for 2012. The Palm Beach County
Solid Waste Authority colony was documented with 1.08 and 0.46
fledgling per nesting attempt in 2011 and 2012, respectively (M.
Morrison, PBC, pers. comm., 2013). The Corkscrew Swamp Sanctuary colony
near Naples, Florida, documented no nesting in 2010-12 (Lauritsen 2010,
p. 12; 2011, p. 14; and 2012, p. 12). Cook (2011, p. 2) reports that
the 2011 productivity in the Everglades was relatively low and that all
820 nests failed in 2012 (Cook, 2012, p. 2).
Georgia: Bryan and Robinette (2008, p. 20) reported rates of 2.3
and 1.6 fledged young per nesting attempt in 2004 and 2005,
respectively, for South Carolina and Georgia. The 2011 and 2012
productivity rates for Georgia were 1.32 and 1.13 (T. Keyes, Georgia
DNR, pers. comm., 2012). During the past 29 years of data collection
(1983-2012) in
[[Page 37092]]
Georgia, the weighted average of all years and colonies was 1.76+0.8
(158 colony-years) with a range of 0.33 to 2.65 (T. Keyes, Georgia DNR,
pers. comm., 2013).
South Carolina: Murphy and Coker (2008, p. 5) reported that since
the wood stork was listed in 1984, South Carolina colonies averaged
2.08 young per successful nest with a range of 1.72 to 2.73. In 2011,
South Carolina productivity was 1.6 fledged young per nest at two
colonies and 1.1 in 2012 at seven colonies monitored (C. Hand, SC DNR,
pers. comm., 2013).
Based upon the nesting population criteria in the recovery plan, we
considered reclassifying the U.S. breeding population of the wood stork
to threatened status because wood storks and their habitat would
continue to receive the protections of the Act, and management efforts
continue to protect, maintain, enhance, and restore habitat to support
a growing population. The U.S. breeding population of the wood stork
has surpassed the recovery criteria for nesting pairs outlined as
necessary for reclassification. As shown in Table 2 of this document,
the nesting population is increasing and well above the
reclassification benchmark (Brooks and Dean 2008, p. 58; and Table 2).
The total number of nesting colonies has remained stable in south
Florida, and the number of colonies in central and north Florida,
Georgia, South Carolina, and North Carolina continue to increase (Ogden
et al. 1987, p. 754; Brooks and Dean 2008, p. 54; Table 1). The nesting
range continues to expand with new colonies documented in North
Carolina, South Carolina, western Georgia, and northern Florida.
Although variable and not well documented, productivity appears to be
sufficient to support continued population growth, as evidenced by the
increasing population and range expansion described above. Population
trends suggest that the overall population may approach the delisting
benchmark of 10,000 nesting pairs during the next 15 to 20 years.
Nesting numbers show a stable or increasing population, however, data
are not available to evaluate the productivity criterion of 1.5 chicks
per nest per year.
Summary of Factors Affecting the Species
Section 4 of the Act and its implementing regulations (50 CFR part
424) set forth the procedures for listing, reclassifying, or removing a
species from the Federal List of Endangered and Threatened Wildlife.
Under section 3 of the Act, a species is ``endangered'' if it is in
danger of extinction throughout all or a ``significant portion of its
range'' and is ``threatened'' if it is likely to become endangered
within the foreseeable future throughout all or a ``significant portion
of its range.'' The word ``range'' refers to the range in which the
species currently exists, and the word ``significant'' refers to the
value of that portion of the range being considered to the conservation
of the species. The ``foreseeable future'' is the period of time over
which events or effects reasonably can or should be anticipated, or
trends extrapolated. A species may be determined to be an endangered or
threatened species due to one or more of the five factors described in
section 4(a)(1) of the Act: (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
existing regulatory mechanisms; or (E) other natural or manmade factors
affecting its continued existence.
The following analysis examines all five factors currently
affecting or that are likely to affect the wood stork within the
foreseeable future:
A. The Present or Threatened Destruction, Modification, or Curtailment
of Its Habitat or Range
Throughout its range in the southeastern United States, wood storks
are dependent upon wetlands for breeding and foraging. Preventing loss
of wood stork nesting habitat and foraging wetlands within a colony's
core foraging area is of the highest priority. In addition, winter
foraging habitat is important to recovery, as it may determine the
carrying capacity of the U.S. wood stork DPS. While the immediacy and
the magnitude of this factor are substantially reduced when compared to
when this species was originally listed, as the population is larger
and occupies a much larger breeding season and nonbreeding season
range, the destruction, fragmentation, and modification of its wetland
habitats continues to occur and could accelerate in the absence of the
protections of the Act.
Hefner et al. (1994, p. 21) estimated that 1.3 million acres of
wetlands lost in the southeastern United States between the mid-1970s
and mid-1980s were located in the Gulf-Atlantic Lower Coastal Plain, an
area upon which wood storks are dependent. Ceilley and Bartone (2000,
p. 70) suggest that short hydroperiod wetlands provide a more important
pre-nesting food source and provide for a greater early nestling
survivorship for wood storks than previously known. Wetlands that wood
storks use for foraging are being lost through permitted activities
where mitigation is provided. However, it is not known if wood stork
foraging wetlands are being replaced with like-quality foraging
wetlands within the core foraging area of an impacted colony. Lauritsen
(2010, pp. 4-5) suggests that today's mitigation practices lead to a
disproportionate loss of short hydroperiod wetlands. The impacts of the
loss of short hydroperiod (isolated) wetlands, which supply most of the
food energy for initiating reproduction (Fleming et al. 1994, p. 754),
may result in no nesting or abandonment of nesting attempts by wood
storks at colonies like Corkscrew Swamp Sanctuary. Lauritsen (2010,
p.2) indicates the historic extent of wet prairies within the core
foraging area of the Corkscrew Swamp colony has decreased by 70
percent, while deep marsh habitat has increased when compared to pre-
development conditions. Frederick and Meyer (2008, p. 15) suggest that
the decline in colony size in Florida reflects the increasingly
fragmented nature of Florida's wetlands resulting from development.
Future projections from reports like Florida 2060 (1000 Friends of
Florida, http://www.1000friendsofflorida.org/connecting-people/florida-smart-growth-advocates-2/) suggest 7 million acres of land could be
converted from rural and natural to urban uses and wetland habitats
will become more isolated and degraded.
The decline of south Florida's Everglades and Big Cypress
ecosystems is well-documented (e.g., Davis and Ogden 1994). Prior to
1970, a majority (70 percent) of the wood stork population nested south
of Lake Okeechobee and declined from 8,500 nesting pairs in the early
1960s to around 500 pairs in the late 1980s and early 1990s (USFWS
1997, p. 10). The primary cause of this decline was the loss of wetland
function of these south Florida ecosystems that resulted in reduced
prey availability or loss of wetland habitats (USFWS 1997, p. 10).
Wood storks use manmade wetlands for foraging and breeding
purposes. Human-made wetlands include, but are not limited to, storm
water treatment areas and ponds, golf course ponds, borrow pits,
reservoirs, roadside ditches, agricultural ditches, drainages, flow-
ways, mining and mine reclamation areas, and dredge material sites. The
impacts can be positive in certain scenarios as these wetlands can
provide protected foraging and nesting habitat, and may offset some
losses of natural wetlands caused by
[[Page 37093]]
development. A significant number of wood stork colonies are located
where water management practices can impact the nesting habitat
negatively. Colonies that are perpetually flooded will have no tree
regeneration. Draining surface waters of a colony's wetland or pond
will prevent wood storks from nesting, and lowered water levels after
nest initiation facilitate raccoon predation. Lowering surface water or
water table may occur through water control structures, manipulating
adjacent wetlands, or water withdrawals from the local aquifer and can
prevent wood storks from nesting or cause colony failure.
Water Management and Prey Availability
Water management and the effect it has on prey availability to
nesting wood storks in south Florida and the Everglades continue to
impact wood stork recovery. A key wood stork goal and prediction of
CERP relates to the ecological bird-prey-hydrology relationship. The
goal to return natural flows and hydropatterns is predicted to result
in a return to natural timing of nesting, the restoration of large wood
stork nesting colonies in the coastal zone and recovery of wood stork
breeding populations in the Everglades. The early results from CERP
suggest that wood storks are responding to the altered water management
regimes and other factors by nesting more consistently in the coastal
zone and by increasing populations (Frederick 2012, p. 38), however,
there is little evidence that timing of nesting is improving for
breeding wood storks in south Florida. Based upon their analysis of
fledgling survival, Borkhataria et al. 2012 (p.525) notes the
possibility that south Florida is currently acting as a population
sink. Frederick (2012, p. 44) states that later nesting increases the
risk of mortality of nestlings that have not fledged prior to the onset
of the wet season, which is likely the difference between the south
Florida segment of the population being a source or a sink to the wood
stork population. CERP is a significant long-term conservation effort
that, if successful in restoring natural flows and hydropatterns, will
greatly benefit wood stork recovery. Frederick (2012, p. 38) indicates
that full restoration of wading bird populations in the Everglades is
predicted as a result of full restoration of key historical
hydropatterns, which have not occurred yet as there are many
restoration projects and management regimes yet to be implemented.
Another concern, Borkhataria et al. (2012, p. 517) show a relationship
between temporally fluctuating hydrologic factors and juvenile wood
stork survival rates, highlighting the need for water management to
also consider the timing of managed wetland manipulations, as human-
induced changes have impacts on when birds nest and ultimately how the
population is fairing. In years with high water levels that resulted in
unsuitable foraging habitat for post-fledging juveniles studied in the
Everglades, the young birds moved into more terrestrial agricultural
and developed landscapes and were more vulnerable to mortality, which
may have been related to relatively low aquatic prey density in those
areas (Borkhataria et al., p. 524)
Conservation managers implement water management regimes at several
large impoundments in Georgia, South Carolina and North Carolina that
support wood stork recovery. Several impounded sites support nesting
colonies and the water management at these sites help to promote
nesting and provide protection from predators. Other impoundments near
nesting colonies are managed to make prey available to the nesting wood
storks to feed their chicks and to chicks when they fledge from the
colonies through water drawdowns that help concentrate prey at optimal
times during the nesting season.
Sea-Level Rise
Climate change is on-going and one of its many effects involves sea
level rise (SLR), which poses widespread and continuing threats to
coastal environments at global, regional, and local levels (Melillo et
al. 2014, pp. 9-10, 397). The effects of sea level rise can include
complete inundation of coastal habitat, as well as intrusion of
saltwater into estuaries and more inland areas, including freshwater
marshes, which can result in changes in the suitability of habitat for
various animal species. These and other changes both now and in the
future depend on the magnitude of the SLR and other factors such as
storm surges (e.g., SCDNR 2013 p. 52; Williams 2013, pp. 188, 191).
Since about 1880, when reliable record-keeping began for sea level,
global sea level has risen about 200 mm (8 in) (Melillo et al., 2014,
p. 21). For more than a century the rate of global mean SLR has been
greater than at any time over the previous two millennia, and the rate
is accelerating: from 1901-2010 the average increase was 1.7 mm/yr
(0.07 (in/yr), from 1971-2010 it was 2.0 mm/yr (0.08 in/yr), and
between 1993-2010 it was 3.2 mm/yr (0.13 in/yr) (Intergovernmental
Panel on Climate Change (IPCC) 2013, p. 11). Although SLR is due in
part to natural variability in the climate system, scientists attribute
the majority of the observed increase in recent decades to human
activities that contribute to ocean thermal expansion related to ocean
warming, and melting of ice: The IPCC reported that approximately 75
percent of the observed increase in global mean SLR since the early
1970's can be explained due to melting of glaciers and ocean thermal
expansion from warming (ibid.), and an estimated 87 percent of the
trend in ocean thermal expansion since 1970 has been induced by human
activity (Marcos and Amores 2014).
Trend data show increases in sea level have been occurring
throughout the southeastern Atlantic and Gulf coasts and according to
Mitchum (2011, p. 9) the overall magnitude in the region has been
slightly higher than the global average. At local levels, SLR varies by
location as well as seasonally. State-by-state averages are available
based on tidal gauge measurements. Measurements summarized for stations
at various locations in Florida indicate SLR there has totaled
approximately 200 mm (8 in.) over the past 100 years, with an average
of about 3.0 mm/yr (0.12 in/yr) since the early 1990's (Ruppert 2014,
p. 2). The relatively few tidal gauges in Georgia, South Carolina, and
southern North Carolina also show increases, the largest being in South
Carolina (NOAA Web site http://tidesandcurrents.noaa.gov/sltrends/sltrends.shtml, accessed May 2 and May 9, 2014).
Continued global SLR is considered virtually certain to occur
throughout this century and beyond (Stocker et al., 2013, p. 100;
Levermann et al. 2013, entire). Depending on the methods and
assumptions used, however, the range of possible scenarios of global
average SLR for the end of this century is relatively large, from a low
of 0.2 meters (m) (approximately 8 in.) to a high of 2 m (approximately
78 in., i.e., 6.6 ft) (Parris et al. 2012, pp. 2, 10-11). Although this
relatively wide range reflects considerable uncertainty about the exact
magnitude of change, it is notable that increases are expected in all
cases, and at rates that will exceed the SLR observed since the 1970's
(IPCC 2013, pp. 25-26).
The highest projection of global sea level rise typically cited is
2 m (approximately 6 ft 7 in) by 2100, which is the high end of the
range of projections provided in a paper by Pfeffer et al. (2008). In
that paper, the projections range from 0.8-2.0 m (2 ft 7.5 inches-6 ft
7 inches). Based on analysis of glaciological conditions that would be
required for a sea level rise of 2 m or more, however, the authors
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concluded that: (1) increases of more than 2 m are ``physically
untenable;'' (2) a rise of about 2 m by 2100 ``could occur under
physically possible glaciological conditions but only if all variables
are quickly accelerated to extremely high limits''; and (3) ``more
plausible but still accelerated conditions'' would result in a rise of
about 0.8 m (2.6 ft) by 2100. They also stated that the assumptions
underlying their range of sea level rise contained ``substantial
uncertainties'' and recognized the need for more study in order to
support improvements in projections (Pfeffer et al., 2008, p. 1342).
Thus it is logical to conclude that although SLR of 2 m (6 ft 7 in) by
the end of the century is theoretically possible, it is not
particularly plausible. This interpretation has been supported in
subsequent literature on SLR. For example, in their review of SLR
projections, Nichols et al. concluded that the upper part of the
projected ranges are possible but not likely to occur (Nicholls et al.
2011, pp. 165, 168).
The IPCC's most recent projections of SLR are based on the four
climate change scenarios they currently use, with a base period of
1986-2005 for comparison. The range of global mean SLR they project for
2046-2065 is 0.24-0.30 m (9.5-11.8 in.), and for 2081- 2100 the range
is 0.40-0.63 m (15.8-24.0 in.) (IPCC 2013, pp. 23-26). The IPCC
acknowledges that higher projections have been made using other types
of sea-level rise models and underlying assumptions, but notes a lack
of consensus in the scientific community about those processes and thus
the IPCC's assessed confidence in those projections (which include the
higher projections of SLR), is low (IPCC 2013, p. 26).
The Third National Climate Assessment (NCA) projects that global
mean sea level will rise another 1-4 feet (i.e., approximately 0.3-1.2
m) in this century (Melillo et al. 2014, pp. 9, 21, 44-45). The NCA
also acknowledges the future scenarios of global SLR range from 8 in to
6.6 ft (0.2-2 m) by the end of the Century, and notes that the
relatively large range reflects differences in climate models, natural
climate variability, uncertainties regarding melting of glacier and the
Antarctic and Greenland ice sheets especially, and future rates of
greenhouse gas emissions (Melillo et al. 2014, p. 45; Carter et al.
2014, p. 414; see also Williams 2013, entire, for a discussion of
various influences on SLR). Emerging scientific information reflects
further concern about possible acceleration in the rate of ice sheet
melting (e.g., Levermann et al., 2013, Moore et al. 2013, Menel and
Levermann 2014). This includes new modeling which indicates early stage
collapse of portions of the West Antarctic Ice sheet has begun, with
enough ice to raise global sea level by 1.2 m (3 ft. 11 in) and no
known obstacles that would preclude continued further melt, although
the time period of melting and effects is somewhat uncertain and is
expected to be moderate during this century and generally increase
after that, and could span two or more centuries (Joughlin et al 2014,
entire; Rignot et al 2014, entire). This information was not available
when the IPCC conducted its modeling, and suggests the ``high'' end of
the IPCC's projected range of SLR, at about 2 feet, may be too
conservative, whereas the higher end (2-4 feet) of the NCA projection
of 1-4 ft. for average global SLR by the end of this Century appears
reasonable. Current modeling capability does not allow precise
projections of SLR at local scales (e.g., see Parris et al. 2012, p. 5;
Williams 2013, pp. 189-190).
The effects of sea level rise include inundation of coastal habitat
and intrusion of saltwater into estuaries and more inland areas
including freshwater marshes, which can result in changes in vegetation
and in the presence and density of various animal species; these and
other changes both now and in the future depend on the magnitude of the
SLR and other factors such as storm surges (e.g., SCDNR 2013 p. 52;
Williams 2013, pp. 188, 191). Although we expect SLR will continue to
occur and even accelerate, the information presented above makes it
clear that the magnitude (with most estimates being in the range of 1-4
feet by the end of this century and as described above the lower half
of the range appears more plausible) as well as the extent to which SLR
will inundate current wood stork habitat is relatively uncertain at
this time.
There also is considerable uncertainty about the likely effects of
SLR on wood stork habitat, and at this point in time we do not have
quantitative predictions of how much nesting habitat or foraging
habitat might be affected by such impacts. Based on the best scientific
information currently available, the effects appear likely to be
mixture of both positive and negative influences on habitat. As noted
in our description of habitat for this species (above) and under Factor
C (below), wood stork colony sites located in standing water must
remain inundated throughout the nesting cycle to protect again
predation and nest abandonment. Sea level rise could result in more
favorable conditions of inundation throughout the nesting cycle in some
areas that currently become seasonally too dry to be suitable.
Conversely, additional inundation could make render some currently
suitable foraging habitat adjacent to nesting colonies too deep to be
suitable as foraging habitat.
The duration of inundation by SLR also will make a difference: As
noted earlier, colonies that are perpetually flooded have no tree
regeneration and thus SLR could result in loss of some colonies over
time at locations where inundation becomes perpetual. At the same time,
SLR could result in development of estuaries and suitable habitat for
nesting and foraging at sites relatively more inland than currently
suitable habitat and thus support range expansion, although human
development and climate change adaptation measures aimed at protecting
human communities and infrastructure could substantially affect the
extent and location of new estuaries that might become established in
the face of a changing climate (e.g., Feagin et al. 2010 entire; Torio
and Chmura 2013 entire).
To summarize, although we acknowledge that SLR is on-going and is
certain to continue at global to local levels, likely at an accelerated
rate, there is considerable uncertainty as to what the magnitude and
rate will be in areas that are part of the wood stork's range, and
inland parts of the range may not be effected at all by SLR. Further,
although we are concerned about the potential effect of SLR on wood
stork habitat, it appears that SLR could result in both positive and
negative changes for the wood stork and we cannot determine what the
net overall effect will be in the foreseeable future in relation to the
threatened destruction, modification, or curtailment of the habitat or
range of the DPS.
Habitat Protection, Acquisition, Restoration
While habitat loss, fragmentation, and degradation continue to
occur throughout the range of the U.S. population of wood stork,
protection, acquisition, and restoration efforts are also in progress.
Natural wetlands are being targeted for acquisition to be protected
through the management of public lands for wildlife and water
conservation (NRCS 2006, p. 1); also see Recovery Task (1) Protect
currently occupied habitat in the Recovery Plans section. The Wetlands
Reserve Program has restored over 200,000 acres of wetlands in Florida
and over 115,000 acres in Alabama, Georgia, and South Carolina during
the past 18 years. Thousands of acres of wetlands are also being
protected on private lands through conservation easements to
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assist in habitat and wildlife protection through restoration (Dahl
2006, p. 16). Wetland losses are being avoided, minimized, and
mitigated through the regulatory process (Votteler and Muir 2002, pp.
1-2). Recommendations for improved implementation and tracking of
wetland mitigation with respect to monitoring and protecting important
wood stork habitat are laying the groundwork for improving the
regulatory system to better protect wood storks. Large-scale
restoration projects like the CERP, Kissimmee River Restoration
Project, and St. Johns River Headwaters Restoration Project are
significant conservation efforts that greatly benefit wood stork
recovery.
Additionally, the species' response to the threat of habitat loss
and degradation indicates its ability to seek out new nesting and
foraging areas. Since 1980, wood storks have expanded their breeding
range north into Georgia, South Carolina, and North Carolina, and the
total number of breeding adults is now approaching the delisting
criterion set out in the species' recovery plan. Seventy percent of the
population now breeds north of Lake Okeechobee and the Everglades
(Brooks and Dean 2008, p. 53). These positive indicators throughout the
range suggest that the viability of the U.S. wood stork DPS may no
longer be as closely tied to the health of the Everglades for
reproduction.
With regard to important wood stork habitats, a number of the
nesting colonies occur on Federal conservation lands and are
consequently afforded protection from development and large-scale
habitat disturbance. Wood stork colonies also occur on a variety of
State-owned properties, and existing State and Federal regulations
provide protection on these sites. However, approximately half of known
wood stork colonies occur on private lands. Through conservation
partnerships, colonies can be protected through the owners'
stewardship. In an effort to minimize potential loss of colony sites,
partnerships have been developed through conservation easements,
wetland restoration projects, and other conservation means. Also, the
wetland areas near nesting colonies play a vital role in the success of
a nesting colony. Due to the regulatory status of wetlands,
conservation of wetlands shown to be important to wood storks can be
largely achieved through the application and improved implementation of
existing wetland laws and mitigation practices, such as the Clean Water
Act (CWA, 33 U.S.C. 1251 et seq.) and the interagency cooperation
provisions under section 7 of the Act.
In summary, loss, fragmentation, and modification of wetland
habitats continue as threats to wood storks. Changes in local habitat
conditions are known to impact wood storks. Based on the best available
scientific information, it is our assessment that the species is
showing the ability to respond to these threats through expansion of
its range, adjusting reproductive timing, and utilizing a variety of
wetlands for foraging, roosting, and breeding, including manmade
wetlands. Historically, the core of the wood stork breeding population
was located in the Everglades and Big Cypress systems of south Florida.
Populations there had diminished because of deterioration of the
habitat. In recognition of the importance of the Everglades and Big
Cypress systems to wood stork recovery, the recovery plan states that,
as a prerequisite for full recovery, these ecosystems should once again
provide the food resources that are necessary to support traditional
wood stork nesting patterns at historical nesting areas. However,
current data show that the breeding range has now almost doubled in
area and shifted northward along the Atlantic coast as far as
southeastern North Carolina. As a result of their range expansion,
dependence of wood storks on any specific wetland complex has been
reduced. Even though habitat destruction and modification are still a
threat to full recovery, the improved wood stork population statistics
suggest that wetland habitat is not yet limiting the population, at
least at the landscape level (USFWS 2007, p. 16). Habitat loss,
fragmentation, and modification of wetland habitats continue around
nesting colonies and core foraging areas, and still threaten the
viability of the U.S. wood stork DPS. There is also considerable
uncertainty about the likely effects of for example SLR on wood storks
and their habitat. Based on the best scientific information currently
available, the effects appear likely to be mixture of both positive and
negative influences on habitat.
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
Monitoring of and research on wood storks over the past 20 years
has increased. A few scientific research permits with potential to harm
individual wood storks have been issued. This level of take/harm is not
expected to adversely impact wood stork recovery or present a threat to
the species.
Wading birds and other waterbird species, including wood storks,
can impact production at fish farms. A Georgia catfish farmer located
approximately 25 miles west of the Chewmill and Birdsville colonies in
Jenkins County, Georgia, has documented hundreds of wood storks
aggregating and foraging on the littoral edges of the ponds during the
late summer in recent years. U.S. Department of Agriculture, Wildlife
Services Division (Wildlife Services) has documented hundreds of wood
storks, and in one case 1,000 wood storks, roosting on fish pond dikes
in the eastern Mississippi, west-central Alabama area (J. Taylor, U.S.
Department of Agriculture, pers. comm., 2007). Wildlife Services found
that the wood storks were generally loafing, and if they were feeding,
they were taking diseased and oxygen-deprived fish and not impacting
production. Nonetheless, operators of fish farms often respond to such
activities by taking wood storks. Unpermitted wood stork take has been
documented at a Mississippi catfish farm and a Florida tropical fish
farm. Each of these incidents ended in prosecution for shooting wood
storks. However, wood stork take at aquaculture facilities likely still
occurs. To what extent this type of take occurs is unknown. Migratory
Bird Treaty Act (MBTA; 16 U.S.C. 701 et seq.) depredation permits
assist in minimizing unauthorized take. Depredation permits are issued
to allow the take of migratory birds that are causing serious damage to
public or private property, pose a health or safety hazard, or are
damaging agricultural crops or wildlife. Wildlife Services provides
expert technical advice and information regarding hazing and harassment
techniques.
Research permits are issued to eliminate or minimize impacts to
wood storks from scientific research. Overutilization was not
identified as a threat at the time of listing in 1984, and we conclude
that overutilization for commercial, recreational, scientific, or
educational purposes is not a threat to the U.S. wood stork DPS now or
in the foreseeable future.
C. Disease or Predation
Limited information is available regarding potential impacts from
disease or parasites. Hematozoa (blood parasites) have been documented
to a limited extent in wood storks in Florida and Georgia (Forrester et
al. 1977, p. 1273; Fedynich et al. 1998, p. 166). Avian malaria has
recently been documented in U.S. wood storks, but the available
information does not indicate that avian malaria is a significant
factor affecting the DPS.
[[Page 37096]]
Adequate water levels under nesting trees or surrounding nesting
islands deter raccoon predation of wood stork colonies. Water level
manipulation or prolonged drought that keeps levels too low can
facilitate raccoon predation of wood stork nests. In many cases,
colonies also have a population of alligators nearby that deter raccoon
predation (Coulter and Bryan 1995, p. 242), and removal of alligators
from a nesting colony site could lead to increased raccoon predation.
On the other hand, as described above (see Factor A), in some areas sea
level rise may result in more favorable water levels that can help
deter predation by raccoons. However, human disturbance may cause
adults to leave nests, exposing the eggs and downy nestlings to
predators (e.g., fish crows), sun, and rain. Great horned owls have
been documented nesting in and near colonies and likely impact the
colony to some degree.
A breeding population of Burmese pythons has been documented in the
Florida Everglades, and a study has documented that pythons preyed upon
wood storks (Dove et al. 2011, p. 128). Given the observed impact they
have had on small mammal populations in south Florida (Dorcas et al.
2012, p. 2418), if these snakes or other species of nonnative reptiles
become established in additional areas within the south Florida
ecosystem, they could pose a significant threat to nesting wood storks
and other species of colonial-nesting water birds. Monitoring and
research is underway to determine the impacts and effects of Burmese
python on wading bird nesting colonies and specifically wood storks and
also to alligator populations in the Everglades. At the present time,
research does not indicate that predation by pythons occurs at a level
that would threaten the U.S. wood stork DPS, now or in the foreseeable
future.
A small number of the nonindigenous sacred ibis (Threskiornis
aethiopicus) were discovered breeding in the Everglades in 2005 and the
exponential population growth rates and expanding distribution of this
species in France demonstrate the potential for this species to become
invasive in Florida (Herring and Gawlik 2008, p. 969). Recent research
has documented the sacred ibis as a predator of both eggs and chicks in
colonial nesting colonies in their native region (Williams and Ward
2006, p. 321), and they could have a negative impact on wood storks and
other colonial nesting birds if a breeding population is established in
Florida. Palm Beach County, the Florida Fish and Wildlife Conservation
Commission, and Wildlife Services recently teamed up to eradicate
invasive sacred ibises where they were known to occur in south Florida,
2007-09. Experts believe that all sacred ibises living in the wild in
south Florida have been removed and are cautiously hopeful that the
sacred ibis has proven to be a ``success story'' for invasive species
management (Johnson and McGarrity 2009, p. 5).
As summarized above, we have a few documented instances of disease
and predation within the range of the U.S. wood stork DPS. However,
this information does not indicate that disease or predation occur at a
level that would threaten the U.S. wood stork DPS, now or in the
foreseeable future.
D. The Inadequacy of Existing Regulatory Mechanisms
In addition to the Act, the MBTA provides Federal protection to the
U.S. wood stork DPS. Florida, Georgia, South Carolina, North Carolina,
Alabama, and Mississippi wildlife laws also list and protect wood
storks. These Federal and State laws prohibit the taking of a wood
stork, their nests, or their eggs, except as authorized through
permitted activities such as scientific research and depredation
permits. However, the MBTA and State laws do not prohibit clearing,
alteration, or conversion of wetland foraging habitats or nesting
colony sites during the non-nesting season.
The CWA regulates dredge and fill activities that would adversely
affect wetlands, which constitute wood stork habitat. Section 404 of
the CWA regulates the discharge of dredged or fill materials into
wetlands. Discharges of dredged or fill materials are commonly
associated with projects to create dry land for development sites,
water-control projects, and land clearing. The U.S. Army Corps of
Engineers (Corps) and the Environmental Protection Agency (EPA) share
the responsibility for implementing the permitting program under
section 404 of the CWA. These Federal actions must not jeopardize the
continued existence of any species protected under the Act.
When impacts to wetlands cannot be avoided or minimized, wetland
mitigation is often employed to replace an existing wetland or its
functions by creating a new wetland, restoring a former wetland, or
enhancing and preserving an existing wetland. This is done to
compensate for the authorized destruction of the existing wetland. As
discussed earlier, it is not known if wood stork foraging wetlands are
being replaced with like-quality foraging wetlands within the core
foraging areas of impacted colonies. Lauritsen (2010, pp. 4-5)
indicates that the Uniform Mitigation Assessment Method (UMAM, http://www.dep.state.fl.us/water/wetlands/mitigation/umam/index.htm) does not
accomplish type-for-type wetland mitigation, which can result in
considerable losses to wetland functions performed only by shallow
short hydroperiod wetlands.
Section 404 of the CWA currently provides little protection for
isolated wetland habitats. A 2001 U.S. Supreme Court opinion (Solid
Waste Agency of Northern Cook County (SWANCC) v. U.S. Army Corps of
Engineers, 531 U.S. 159 (2001)) substantially reduced the jurisdiction
of the Federal Government in regulating isolated wetlands. While many
States in the southeastern United States regulate those activities
affecting wetlands that are not protected by section 404 of the CWA,
Florida is the only State known to regulate isolated wetlands. In South
Carolina, Georgia, Alabama, and North Carolina, no State laws protect
isolated wetlands. The EPA and the Corps have developed a proposed rule
to clarify whether a waterway, water body, or wetland is protected by
the CWA and have sent this proposed rule to the Office of Management
and Budget for interagency review. The EPA/Corps proposed rule will
provide greater consistency, certainty, and predictability nationwide
by providing clarity in determining where the CWA applies. The proposed
rule is limited to clarifying current uncertainty concerning the
jurisdiction of the CWA that has arisen as an outgrowth of Supreme
Court decisions. It focuses on clarifying protection of the network of
smaller waters that feed into larger ones, to keep downstream water
safe from upstream pollutants. It would also clarify protection for
wetlands that filter and trap pollution, store water, and help keep
communities safe from floods. However, the proposed rule does not
propose changes to existing regulatory exemptions and exclusions. For
more information see (http://water.epa.gov/lawsregs/guidance/wetlands/CWAwaters.cfm).
Within the range of the wood stork in the southeastern U.S., a wide
array of activities have begun at Federal, State, County, and local
levels which involve analysis and planning for climate change,
especially with regard to sea level rise and associated storm surge in
coastal areas. These efforts are in the early stages of development and
the situation is complicated by uncertainty about the magnitude and
rate of climate change and its effects, including the possibility of
both positive and negative effects on the wood stork. Thus we do not
have a basis at this time for
[[Page 37097]]
assessing the possible effectiveness of such that will assist us in
addressing climate change in relation to wood stork populations and
habitat.
The Service's Wood Stork Habitat Management Guidelines (Ogden 1990)
recommend that active colony sites be protected from local hydrologic
changes and from human activities (e.g., timber harvesting, vegetation
removal, construction, and other habitat-altering activities) that are
likely to be detrimental to the colony (USFWS 1997, p. 18). The Service
also recommends that feeding sites be protected to the maximum extent
possible. The Service's North and South Florida Ecological Services
Field Offices have developed ``May Affect'' keys to assist regulators
with review of wetland dredge and fill permit applications and in an
effort to minimize loss of wetland habitats important to wood stork
recovery, like those within the core foraging area of a nesting colony.
In summary, a number of regulatory mechanisms implemented by
Federal and State agencies protect wood storks and conserve their
habitat. Take of wood storks is illegal under both the Act and MBTA.
The CWA minimizes impacts on jurisdictional wetlands that are important
to wood storks; however, the CWA alone is not sufficient to eliminate
all impacts, as discussed in Factor A. Whether existing habitat
protections and conservation mechanisms are inadequate can be assessed
only by monitoring the status of the wood stork population. Recent
trends indicate that the range is expanding and the breeding population
has increased, suggesting that the combination of the CWA, the Act, the
MBTA, and State regulations are adequate to protect jurisdictional
wetlands to allow population growth. However, non-jurisdictional
wetlands continue to be lost to development due to lack of existing
regulatory mechanisms, and, therefore, loss of these wetlands continues
as a threat to this species.
E. Other Natural or Manmade Factors Affecting Its Continued Existence
Changes in Climate Suitability
One of the concerns related to the effects of climate change is
whether the size of the area with climate conditions that are suitable
for a species will shrink substantially or change in location relative
to the current range of a species, as well as the ability of a species
to shift its range in a timely way, if needed. One approach for
assessing such possibilities involves climate envelope modeling (CEM),
which is a type of species distribution modeling that involves
predicting the future locations of climate suitability for a species
based on a correlation between its current or past occurrence and
climate information, such as the minimum and maximum climate conditions
(the ``climate envelope'') where the species occurs (Watling et al.
2013, p. 36). The wood stork is one of several species in the
southeastern U.S. for which climate modeling has been conducted to make
predictions for the 20-year period 2041-2060, and the wood stock is one
of the species for which the climate envelope (i.e., area of climate
suitability) is predicted to expand (Bucklin et al. 2012, entire;
Watling et al., 2012, pp. 1-8).
More specifically, the results of Watling et al. (2012, p. 6)
predict that for 2041-2060 the relative size of the climate envelope
for the wood stork will expand to approximately 5.6 times the size of
the contemporary climate envelope in the Southeast. (Data for this
prediction are available via http://crocdoc.ifas.ufl.edu/projects/climateenvelopemodeling/ and maps depicting the current and predicted
climate envelopes for the wood stock based on these data are in our
files.) Also, although a comparison of two different approaches for
dealing with climate projections yielded somewhat different predictions
of the likely area of climate suitability for 2041-2060, both
approaches predicted increases in the size of the area of the climate
envelope in the southeast for the woodstork (Bucklin et al. 2012, pp.
7-10). The climate envelope information does not mean that the wood
stork will change its range to match the changing conditions that were
modeled. Nevertheless, the study results, plus the fact that the wood
stork is capable of expanding its range (as described in the
Distribution section, above), lead us to conclude that the potential
changes in temperature and precipitation associated with a changing
climate over the next several decades, as considered in the models, are
not going to be limiting for the southeastern U.S. DPS of the wood
stork. It also is significant that a recent assessment which considered
the wood stork throughout its entire range (i.e., not limited to the
southeast U.S. DPS) concluded that the species has overall low
vulnerability to various impacts of climate change (Foden et al. 2013,
Appendix A).
Contamination Events
Contamination events can be triggered by restoration or natural
events, such as hurricanes or flooding, that can expose concentrations
of contaminants. For example, from November 1998 through early April
1999, a bird mortality event occurred on the north shore of Lake
Apopka, Florida, on former farmlands that had been purchased by the St.
Johns River Water Management District and NRCS. An estimated 676 birds
died on-site, mostly white pelicans (Pelecanus erythrorhynchos) and
various species of wading birds, including the wood stork. Of the
estimated 1,991 wood storks present in the area, 43 died on-site
(Rauschenberger 2007, p. 16). The cause of death was attributed to
organochlorine pesticide (OCP) toxicosis (Rauschenberger 2007, p. 16).
The birds were exposed to OCPs by eating OCP-contaminated fish, which
became easy prey as fish moved from ditches into the flooded fields,
located in the eastern part of the restoration area (Rauschenberger
2007, p. 16).
Mercury, heavy metals, and other contaminants that may impair
reproduction and cause other health issues are being studied in wood
storks and many other wading bird species (Bryan et al. 2012; Gallagher
et al. 2011; Martin 2010; Frederick and Jayasena 2010; Brant et al.
2002; Bryan et al. 2001; Gariboldi et al. 2001). Wetlands in the
southeastern United States have many ecosystem attributes ideal for
promoting high methylmercury production rates (inorganic mercury
converts to methylmercury in the natural environment and fish-eating
birds will accumulate this toxin in their systems) (Hall 2008, p. 124)
and are probably a threat throughout the range. Frederick and Jayasena
(2010, p. 1851) suggest reduced productivity from sublethal effects of
mercury in white ibis; it is possible that wood storks could also be
impacted but this theory requires further investigation. Also, exposure
to contaminants by foraging in manmade wetlands may pose a potential
risk to wood stork health and reproduction. On the other hand,
pesticide contamination has not generally been considered to adversely
affect wood stork reproduction (Bowerman et al. 2007, p. 1506;
Ohlendorf et al. 1978, p. 616).
Oil spills are a concern for the U.S. wood stork DPS; however, very
few cases of actual oiled wood storks have been documented. The
magnitude of the threat that oil spills play to wood stork recovery and
their habitats is unknown and is dependent on the frequency and extent
and timing of a spill. Wood stork protection should be specified
explicitly in contaminant spill contingency plans which involve State
and Federal agencies, along with local oil spill control groups, in
efforts to contain and
[[Page 37098]]
clean up leaks and spills which could impact wood stork habitat; haze
wood storks away from the spill areas and capture and treat individuals
that become seriously contaminated.
Algal Blooms (Red Tide Events)
Harmful algal blooms, specifically red tide events, have become
more prevalent along Florida's coast. Hallegraeff (2010, p. 1) and
Moore et al. (2008, p. 220) suggest the likelihood that harmful algal
blooms will increase due to climate change. Brevetoxicosis (caused by
taking in a brevetoxin produced by Karenia brevis) was documented in
2005 as the cause of death of a wood stork (Spalding 2006). Wood storks
can be exposed to harmful microalgae and their toxins through a variety
of mechanisms, including aerosolized transport (i.e., respiratory
irritation in mammals, turtles, birds); bioaccumulation through
consumption of prey containing toxins or toxic cells (crustaceans,
gastropods, fish, birds, turtles, mammals); and mechanical damage by
spines, setae, or other anatomical features of the cells (FWC 2007, p.
1). In addition to dead fish, large numbers of aquatic birds,
particularly double-crested cormorants (Phalacrocorax auritus), red-
breasted mergansers (Mergus merganser), and lesser scaup (Aythya
affinis), were found moribund or dead in red tide areas during the
Florida west coast Karenia brevis red tide of October 1973 to May 1974
(FWC 2007).
Electrocution
Electrocution mortalities of wood storks from power lines have been
documented and reported to us by power companies and by State and
Federal wildlife law enforcement. In most cases, when a problem
location is identified, it is retrofitted using standard avian
protection guidelines to prevent electrocutions. The guidelines
recommend using heavily insulated wire, spreading the wires apart to
prevent grounding as body parts touch the wires, or burying the wires
underground. The Service's Wood Stork Habitat Management Guidelines
(Ogden 1990) include recommendations that new transmission lines be at
least 1 mile away from colony sites and tall transmission towers no
closer than 3 miles from active colonies. The Service also recommends
similar guidance for cell phone towers and wind turbines. These
recommended distances are provided to help minimize the risk of
powerline and tower collisions. The guidelines are intended to protect
both adult wood storks making foraging forays to and from the colony to
feed chicks and also fledglings that are learning to fly and making
foraging forays to and from the colony.
Other Threats
The following is a list of threats that have also been documented
to occur, but we have concluded that, due to low incident numbers and
minimal documentation, the impacts at this time are very low and do not
impede recovery.
Human disturbance is known to have a detrimental effect on wood
stork nesting (USFWS 1997, pp. 10, 12). Wood storks have been
documented to desert nests when disturbed by humans, thus exposing eggs
and young birds to the elements and to predation by gulls and fish
crows (Coulter et al. 1999, p. 19).
Documentation of road kill mortalities of wood storks has increased
(B. Brooks, USFWS, pers. comm., 2010). Many factors may contribute to
this, such as better reporting or more storks using roadside ponds,
ditches, swales, and flow-ways as foraging habitat.
Hurricanes are an environmental factor that can impact large areas
of the 6 state geographic range in the southeast U.S. of the U.S. wood
stork DPS both in positive and negative ways depending upon frequency
and intensity. According to the National Climate Assessment, there is
considerable uncertainty about the details of hurricane activity prior
to the 1980s, when data from satellites became available. Since the
1980s, measures of the Atlantic hurricane activity have increased
substantially, including the intensity, frequency, duration, and number
of strongest (Category 4 and 5) hurricanes. There also is uncertainty
about the role of natural variability in these recent changes in
hurricane activity, as compared to the role of human-caused changes in
climate. As for the future, on average, models project a slight
decrease in the annual number of tropical cyclones, but an increase in
the number of the strongest (Category 4 and 5) hurricanes over this
century. Most of the existing studies also project greater rainfall
rates during hurricanes in a warmer climate (Walsh et al. 2014, pp. 41-
42; 65; Carter et al. 2014, p. 399).
Stochastic events, including hurricanes but also severe
thunderstorms, do pose other potential risks. Loss of nesting trees due
to storm events can have a negative impact on nesting habitat. Severe
local storm events have impacted individual colonies, causing chick
mortality and even blowing nests out of trees. There are also benefits
to wood stork habitat from large rain events associated with hurricanes
and other storm systems. Timing of rain events can impact active
colonies and local foraging conditions. However, large rain events can
also improve hydrologic conditions locally and regionally for current
and future nesting seasons. They can also reduce impacts of the
nutrient overload to the nesting vegetation and dilute the nutrient
load within the wetland from the guano produced by a colony.
As described previously, most wood stork colonies in the
southeastern United States have relatively short survival histories and
only a handful of colonies have survived more than 20 years. The large
numbers of short-lived colonies indicate that colony abandonment and
novel colony initiation seems to be typical of the species (Tsai et al.
2011, p. 2). The wood stork's ability to seek out new locations for
nesting indicates they will continue to respond in a similar fashion to
changes in habitat availability that result from changes in habitat
suitability associated with hurricanes or other storm events. With
regard to foraging, they respond to habitat changes on daily, seasonal,
and annual basis, and in drought vs wet years, as well as in the
breeding vs non-breeding seasons. This has included responding to major
changes that have occurred in the Everglades, where some still nest.
They also have expanding their breeding range. Consequently despite
past, on-going, and plausible future changes in hurricanes and other
severe storms, we anticipate both positive and negative effects
depending upon timing, frequency and intensity.
The invasion of exotic plants into natural wetland areas can
prevent wood storks from foraging due to high density and canopy cover
of the plants (USFWS 2010, p. 127). Invasion into natural nesting
habitats by exotic species, including Brazilian pepper (Schinus
terebinthifolius), melaleuca (Melaleuca quinquenervia), and Australian
pine (Casuarina equisetifolia), may present a problem; however, wood
storks are using exotic species for nesting habitat at many manmade
wetland colony sites, such as borrow pits. Even though wetlands
overgrown with exotics may preclude wood storks from foraging within,
they do have a conservation benefit as they flood during the wet season
and provide a prey source to adjacent wetlands. Wood storks are also
documented utilizing Brazilian pepper as nesting substrate (USFWS 1999,
p. 4-396).
[[Page 37099]]
Summary of Factor E
In summary, other natural or manmade factors affecting the wood
stork's continued existence, such as contaminants, harmful algal
blooms, electrocution, road kill, invasion of exotic plants and
animals, human disturbance, and stochastic events, are all documented
at minimal levels to affect wood storks.
We have no evidence that observed increased temperatures associated
with climate change have had an adverse effect on the U.S. wood stork
DPS or its habitat. The climate envelope modeling (described above)
indicates a substantial increase in the area of suitable temperature
conditions and precipitation for the species in the coming decades.
Hurricane activity has increased since the 1980s, and although the
number of tropical cyclones may decrease in the future, there may be an
increase in severe, i.e., class 4 and class 5, hurricanes. The wood
stork has evolved under conditions that have included considerable
variability habitat distribution and abundance, and conditions that
include exposure to hurricanes of varying magnitude. The wood stork
utilizes a wide variety of habitats throughout its range in the
southeastern United States; this ability to use alternative habitats
(as evidenced by the wood storks' expansion from the Everglades of
Florida into marshes and tidal areas throughout the southeastern United
States (Brooks and Dean 2008, p. 58), helps to buffer this species from
some of the impacts to its habitat through natural or manmade threats.
We conclude that other natural or manmade factors are not a significant
factor affecting the U.S. wood stork DPS, now or in the foreseeable
future.
Conclusion
Whether a species is currently on the brink of extinction in the
wild depends on the life history and ecology of the species, the nature
of the threats, and the species' response to those threats. Loss,
fragmentation, and modification of wetland habitats continue as threats
to U.S. wood storks. Based on the best available scientific
information, our assessment is that the species is showing the ability
to respond to these threats through expanding its range, adjusting its
reproductive timing, and utilizing a variety of wetlands, including
manmade wetlands, to forage, roost, and breed. Current data show that
the breeding range has now almost doubled in extent and shifted
northward along the Atlantic coast as far as southeastern North
Carolina. As a result, dependence of wood storks on any specific
wetland complex has been reduced. Even though habitat destruction and
modification are still a threat to recovery, the improved wood stork
population statistics also suggest that wetland habitat is not yet
limiting the population, at least at the landscape level.
A number of regulatory mechanisms are being implemented by Federal
and State agencies to protect wood storks and conserve their habitat.
Take of wood storks is illegal under both the Act and MBTA. Whether
habitat protection and conservation mechanisms are inadequate must be
assessed in terms of the wood stork population. Recent trends indicate
that the range of the U.S. wood stork DPS is expanding and that the
breeding population has increased, suggesting that existing regulatory
mechanisms are adequate to allow population growth. However, we remain
concerned that the status of this species would be expected to
deteriorate should the Act's requirements to consult on all Federal
actions affecting the species' habitat or the prohibition on take
(including significant habitat modification) be removed. We recognize
there are significant recommendations that we can make to help improve
implementation of regulatory mechanisms to further minimize impacts to
wetland habitats and we intend to work with our partners to work on and
address these issues.
Other threats such as overutilization of the species for
commercial, recreational, scientific, or educational purposes; disease
and predation; and other natural or manmade factors (e.g.,
contaminants, harmful algal blooms, electrocution, road kill, invasion
of exotic plants and animals, human disturbance, and stochastic events)
are known to occur but are not significant.
While there continue to be ongoing threats, the U.S. wood stork DPS
is increasing and expanding its overall range. Population criteria for
reclassification have been exceeded with 3-year population averages
higher than 6,000 nesting pairs since 2003 (range of 7,086 to 10,147
nesting pairs). Delisting criteria of 10,000 nesting pairs (5-year
average) has not been achieved. The wood stork population has exceeded
10,000 nesting pairs twice during the past 5 years (2006 and 2009), and
the 2009 count of 12,720 nesting pairs represents the highest count
since the early 1960s. Productivity, though variable, is sufficient to
support a growing population. Based on the analysis presented above and
the fact that the nesting pair reclassification criteria has been met
and exceeded and productivity appears to be supporting a growing
population, we have determined the U.S. wood stork DPS is not presently
in danger of extinction throughout its range. Because loss,
fragmentation, and modification of wetland habitats continue around
nesting colonies and core foraging areas, and biological goals of the
recovery plan are still applicable, we conclude that the U.S. wood
stork DPS is likely to become endangered within the foreseeable future
and, therefore, should be reclassified as threatened under the Act.
Significant Portion of the Range Analysis
Having determined that the U.S. wood stork DPS meets the definition
of threatened, we must next consider whether there is a significant
portion of the range where the wood stork remains in danger of
extinction. The phrase ``significant portion of its range'' (SPR) is
not defined by the Act, and we have never addressed in our regulations:
(1) The outcome of a determination that a species is either endangered
or likely to become so throughout a significant portion of its range,
but not throughout all of its range; or (2) what qualifies a portion of
a range as ``significant.''
Two district court decisions have addressed whether the SPR
language allows the Service to list or protect less than all members of
a defined ``species'': Defenders of Wildlife v. Salazar, 729 F. Supp.
2d 1207 (D. Mont. 2010), concerning the Service's delisting of the
Northern Rocky Mountain gray wolf (74 FR 15123, April 2, 2009); and
WildEarth Guardians v. Salazar, 2010 U.S. Dist. LEXIS 105253 (D. Ariz.
Sept. 30, 2010), concerning the Service's 2008 finding on a petition to
list the Gunnison's prairie dog (73 FR 6660, February 5, 2008). The
Service had asserted in both of these determinations that it had
authority, in effect, to protect only some members of a ``species,'' as
defined by the Act (i.e., species, subspecies, or DPS), under the Act.
Both courts ruled that the determinations were arbitrary and capricious
on the grounds that this approach violated the plain and unambiguous
language of the Act. The courts concluded that reading the SPR language
to allow protecting only a portion of a species' range is inconsistent
with the Act's definition of ``species.'' The courts concluded that,
once a determination is made that a species (i.e., species, subspecies,
or DPS) meets the definition of ``endangered species'' or ``threatened
species,'' it must be placed on the list in its entirety and the Act's
protections applied consistently to all members of that species
(subject to modification of
[[Page 37100]]
protections through special rules under sections 4(d) and 10(j) of the
Act).
Consistent with that interpretation, and for the purposes of this
rule, we interpret the phrase ``significant portion of its range'' in
the Act's definitions of ``endangered species'' and ``threatened
species'' to provide an independent basis for listing a species in its
entirety; thus there are two situations (or factual bases) under which
a species would qualify for listing: A species may be endangered or
threatened throughout all of its range; or a species may be endangered
or threatened in only a significant portion of its range. If a species
is in danger of extinction throughout an SPR, it, the species, is an
``endangered species.'' The same analysis applies to ``threatened
species.'' Therefore, the consequence of finding that a species is
endangered or threatened in only a significant portion of its range is
that the entire species will be listed as endangered or threatened,
respectively, and the Act's protections will be applied across the
species' entire range.
We conclude, for the purposes of this rule, that interpreting the
SPR phrase as providing an independent basis for listing is the best
interpretation of the Act because it is consistent with the purposes
and the plain meaning of the key definitions of the Act; it does not
conflict with established past agency practice (i.e., prior to the 2007
Department of the Interior Solicitor's Opinion), as no consistent,
long-term agency practice has been established; and it is consistent
with the judicial opinions that have most closely examined this issue.
Having concluded that the phrase ``significant portion of its range''
provides an independent basis for listing and protecting the entire
species, we next turn to the meaning of ``significant'' to determine
the threshold for when such an independent basis for listing exists.
Although there are potentially many ways to determine whether a
portion of a species' range is ``significant,'' we conclude, for the
purposes of this rule, that the significance of the portion of the
range should be determined based on its biological contribution to the
conservation of the species. For this reason, we describe the threshold
for ``significant'' in terms of an increase in the risk of extinction
for the species. We conclude that a biologically based definition of
``significant'' best conforms to the purposes of the Act, is consistent
with judicial interpretations, and best ensures species' conservation.
Thus, for the purposes of this rule, a portion of the range of a
species is ``significant'' if its contribution to the viability of the
species is so important that, without that portion, the species would
be in danger of extinction.
We evaluate biological significance based on the principles of
conservation biology using the concepts of redundancy, resiliency, and
representation. Resiliency describes the characteristics of a species
that allow it to recover from periodic disturbance. Redundancy (having
multiple populations distributed across the landscape) may be needed to
provide a margin of safety for the species to withstand catastrophic
events. Representation (the range of variation found in a species)
ensures that the species' adaptive capabilities are conserved.
Redundancy, resiliency, and representation are not independent of each
other, and some characteristic of a species or area may contribute to
all three. For example, distribution across a wide variety of habitats
is an indicator of representation, but it may also indicate a broad
geographic distribution contributing to redundancy (decreasing the
chance that any one event affects the entire species), and the
likelihood that some habitat types are less susceptible to certain
threats, contributing to resiliency (the ability of the species to
recover from disturbance). None of these concepts is intended to be
mutually exclusive, and a portion of a species' range may be determined
to be ``significant'' due to its contributions under any one of these
concepts.
For the purposes of this rule, we determine if a portion's
biological contribution is so important that the portion qualifies as
``significant'' by asking whether, without that portion, the
representation, redundancy, or resiliency of the species would be so
impaired that the species would have an increased vulnerability to
threats to the point that the overall species would be in danger of
extinction (i.e., would be ``endangered''). Conversely, we would not
consider the portion of the range at issue to be ``significant'' if
there is sufficient resiliency, redundancy, and representation
elsewhere in the species' range that the species would not be in danger
of extinction throughout its range if the population in that portion of
the range in question became extirpated (extinct locally).
We recognize that this definition of ``significant'' establishes a
threshold that is relatively high. On the one hand, given that the
outcome of finding a species to be endangered or threatened in an SPR
would be listing the species throughout its entire range, it is
important to use a threshold for ``significant'' that is robust. It
would not be meaningful or appropriate to establish a very low
threshold whereby a portion of the range can be considered
``significant'' even if only a negligible increase in extinction risk
would result from its loss. Because nearly any portion of a species'
range can be said to contribute some increment to a species' viability,
use of such a low threshold would require us to impose restrictions and
expend conservation resources disproportionately to conservation
benefit: Listing would be rangewide, even if only a portion of the
range of minor conservation importance to the species is imperiled. On
the other hand, it would be inappropriate to establish a threshold for
``significant'' that is too high. This would be the case if the
standard were, for example, that a portion of the range can be
considered ``significant'' only if threats in that portion result in
the entire species' being currently endangered or threatened. Such a
high bar would not give the SPR phrase independent meaning, as the
Ninth Circuit held in Defenders of Wildlife v. Norton, 258 F.3d 1136
(9th Cir. 2001).
The definition of ``significant'' used in this rule carefully
balances these concerns. By setting a relatively high threshold, we
minimize the degree to which restrictions would be imposed or resources
expended that do not contribute substantially to species conservation.
But we have not set the threshold so high that the phrase ``in a
significant portion of its range'' loses independent meaning.
Specifically, we have not set the threshold as high as it was under the
interpretation presented by the Service in the Defenders litigation.
Under that interpretation, the portion of the range would have to be so
important that current imperilment there would mean that the species
would be currently imperiled everywhere. Under the definition of
``significant'' used in this rule, the portion of the range need not
rise to such an exceptionally high level of biological significance.
(We recognize that if the species is imperiled in a portion that rises
to that level of biological significance, then we should conclude that
the species is in fact imperiled throughout all of its range, and that
we would not need to rely on the SPR language for such a listing.)
Rather, under this interpretation we ask whether the species would be
endangered everywhere without that portion, i.e., if that portion were
completely extirpated. In other words, the portion of the range need
not be so important that even being in danger of extinction in that
portion would be sufficient to cause the remainder of the
[[Page 37101]]
range to be endangered; rather, the complete extirpation (in a
hypothetical future) of the species in that portion would cause the
remainder of the range to be endangered.
The range of a species can theoretically be divided into portions
in an infinite number of ways. However, there is no purpose to
analyzing portions of the range that have no reasonable potential to be
significant and threatened or endangered. To identify only those
portions that warrant further consideration, we determine whether there
is substantial information indicating that: (1) The portions may be
``significant,'' and (2) the species may be in danger of extinction
there or likely to become so within the foreseeable future. Depending
on the biology of the species, its range, and the threats it faces, it
might be more efficient for us to address the significance question
first or the status question first. Thus, if we determine that a
portion of the range is not ``significant,'' we do not need to
determine whether the species is endangered or threatened there; if we
determine that the species is not endangered or threatened in a portion
of its range, we do not need to determine if that portion is
``significant.'' In practice, a key part of the portion status analysis
is whether the threats are geographically concentrated in some way. If
the threats to the species are essentially uniform throughout its
range, no portion is likely to warrant further consideration. Moreover,
if any concentration of threats applies only to portions of the
species' range that clearly would not meet the biologically based
definition of ``significant,'' such portions will not warrant further
consideration.
Applying the process described above, we evaluated the U.S. wood
stork DPS's range to determine if any areas could be considered a
significant portion of its range, and a key portion of that
determination is whether the threats are geographically concentrated in
some manner. As detailed in the threat analysis in this rule, the
primary threat to the wood stork--habitat loss, fragmentation, and
modification--is a relatively uniform threat across the species' range.
It could be argued that, at the time of listing, the threat of
habitat destruction and fragmentation to the U.S. wood stork DPS at one
time was concentrated in south Florida. With the current habitat
regimes, nesting wood storks have persisted in south Florida with
nesting numbers below historic counts but also varying annually from
hundreds to several thousand in many years (Table 2). Even though we
note above that no concentration of threats currently occurs in the
range of this DPS, we provide here more detail on south Florida to
determine whether it is a significant portion of the range in light of
the emphasis on south Florida in the wood stork recovery plan.
The wood storks nesting in south Florida (the region south of Lake
Okeechobee from Lee County on the west coast to Palm Beach County on
the east coast, and the Everglades and Big Cypress systems) now
represent approximately 25 percent of the breeding wood storks in the
United States during the past 10 years (Tables 1 and 2). Total nesting
pairs in this region have been variable, but showed a general pattern
of decline during the 1970s and remained low through the mid-1980s.
However, wood stork nesting increased in south Florida from the mid-
1990s (an average of 400 to 500 pairs) to a high of 5,816 pairs in
2009. A 3-year running average since the time of listing in 1984 ranges
from 457 to 3,449 pairs, with considerable variability. These observed
fluctuations in the nesting between years and nesting sites have been
attributed primarily to variable hydrologic conditions during the
nesting season and timing of the nesting season (Crozier and Gawlik
2003, p. 1; Crozier and Cook 2004, pp. 1-2; Frederick 2012, p. 44).
Frequent, heavy rains during nesting can cause water levels to increase
rapidly. The abrupt increases in water levels during nesting, termed
reversals (Crozier and Gawlik 2003, p. 1), may cause late nest
initiation, nest abandonment, re-nesting, and poor fledging success.
For example, optimal foraging conditions in 2006 resulted in high
nesting success, but the 2-year drought that followed in 2007 and 2008
resulted in no nesting success in the Corkscrew Sanctuary rookery
(Lauritsen 2007, p. 11; Lauritsen 2008, p. 12). However, 2009 nesting
data for Corkscrew Sanctuary rookeries noted 1,120 nests producing
2,570 nestlings (Lauritsen 2009, p. 13). Similar rebounds in nesting
activity were recorded for other south Florida rookeries in 2009, with
possibly the largest number of nest starts since 1975, estimated at
about 4,000 nests throughout the Everglades and Big Cypress Systems
(Newman 2009, p. 51) and a total of 5,816 nesting pairs in south
Florida and counts of 2,100 and 1,200 in 2011 and 2012, respectively
(Table 2). Frederick (2012, p. 44) states that later nesting increases
the risk of mortality of nestlings that have not fledged prior to the
onset of the wet season, which is likely the difference between the
south Florida segment of the population being a source or a sink to the
wood stork population.
The CERP established performance measures and related goals for
wood storks and other wading bird species. Metrics include the number
of pairs of nesting wood storks and the location of the wood stork
colonies. The timing of nesting, which shifted from historical periods
of November through December to January through March, is also a
metric. These metrics have shown some recent positive measures in
Everglades restoration. Restoration models predict that the return of
natural flows and hydrologic patterns will result in large, sustainable
breeding wading bird populations, with large colonies in the coastal
zone of the Everglades and a return to natural timing of nesting, with
wood stork nest initiation in November or December. Cook and Kobza
(2010, p. 2) suggest that Everglades National Park may be more
attractive to nesting birds in recent years and that the 2009 breeding
season was the best nesting year in south Florida since the 1940s. The
2009-2010 nesting year did show an improvement in nest timing with wood
stork nesting in January, which is earlier than previous years, but
still outside the nesting onset target of November to December (Newman
2009, p. 52; Gottlieb 2010, p. 42). Cook and Kobza (2010, p. 2) report
a general shift of colony locations to the coast in recent years.
Frederick (2012, p. 44) also confirms more wood storks nesting in
coastal colonies and an increase in the number of wood storks nesting
in the Everglades since 1986; however, there appears to be little
improvement on the timing of nesting (Frederick 2012, p. 44).
Although the variability of habitat conditions affects the nesting
efforts in south Florida and at times total failure of a colony occurs
or little to no nesting, we do not believe such variability will cause
extirpation of wood storks in south Florida. Wood storks are a long-
lived species that demonstrate considerable variation in population
numbers in response to changing hydrological conditions (USFWS 1997, p.
10). We are not aware of any other threat within this portion of the
range that would act synergistically and heighten our level of concern
for the wood stork population. Consequently, we recognize that it is
desirable to improve the nesting success of wood storks in south
Florida, and timing of nest initiation appears to be a key factor.
However, we conclude that the present level of habitat threat, when
combined with the restoration efforts of CERP and the significant
number of wood storks nesting in south Florida and throughout
[[Page 37102]]
the range, is not of a magnitude that leads us to delineate the wood
storks in and around south Florida as being more in danger of
extirpation than wood storks breeding in central/north Florida through
North Carolina, nor as being a significant portion of the range of the
U.S. wood stork DPS.
In summary, the primary threats to the U.S. wood stork DPS (habitat
loss, fragmentation, and modification) are relatively uniform
throughout the DPS's range.
A growing population with an expanding distribution provides less
risk to the species and the breeding range extension makes them less
vulnerable to the potential threats. We have determined that none of
the existing or potential threats currently place the U.S. wood stork
DPS in danger of extinction throughout all or a significant portion of
its range. The best available information indicates the U.S. wood stork
DPS is likely to become an endangered species within the foreseeable
future throughout all of its range due to the impacts of habitat loss,
fragmentation, and modification. Thus, the U.S. wood stork DPS meets
the definition of a threatened species throughout its range.
Available Conservation Measures
Conservation measures provided to species listed as endangered or
threatened under the Act include recognition, recovery actions,
requirements for Federal protection, and prohibitions against certain
practices. Recognition through listing increases public awareness of
threats to the U.S. breeding population of the wood stork, and promotes
conservation actions by Federal, State, and local agencies, private
organizations, and individuals. The Act provides for possible land
acquisition and cooperation with the States, and for recovery planning
and implementation. The protection required of Federal agencies and the
prohibitions against taking and harm are discussed, in part below.
A number of the nesting colonies of the U.S. wood stork DPS occur
on Federal conservation lands and are consequently afforded protection
from development and large-scale habitat disturbance. Wood stork
colonies also occur on a variety of State-owned properties, and
existing State and Federal regulations provide protection on these
sites. A significant number of wood stork colonies occur on private
lands, and through conservation partnerships, many of these colonies
are protected through the owners' stewardship. In many cases, these
partnerships have been developed through conservation easements,
wetland restoration projects, and other conservation means. The fact
that wood stork habitat is primarily wetlands also assures the
opportunity for conference or consultation on most projects that occur
in wood stork habitat under the authorities described below.
Section 7(a) of the Act, as amended, requires Federal agencies to
evaluate their actions with respect to the U.S. breeding population of
the wood stork. If a Federal action may affect the wood stork or its
habitat, the responsible Federal agency must consult with the Service
to ensure that any action authorized, funded, or carried out by such
agency is not likely to jeopardize the continued existence of the wood
stork. Federal agency actions that may require consultation with us
include Corps' involvement in projects such as residential development,
mining operations, construction of roads and bridges, or dredging that
requires dredge/fill permits. Protecting and restoring wetlands that
wood storks are dependent upon through the environmental regulatory
review process is the most important action that Federal, State, and
local regulatory agencies can undertake and is key to wood stork
recovery.
The Act and its implementing regulations set forth a series of
general prohibitions and exceptions that apply to all endangered and
threatened wildlife. As such, these prohibitions would be applicable to
the wood stork. These prohibitions, under 50 CFR 17.21 (17.31 for
threatened wildlife species), make it illegal for any person subject to
the jurisdiction of the U.S. to ``take'' (including to harass, harm,
pursue, hunt, shoot, wound, kill, trap, capture, collect, or to attempt
any of these) within the United States or upon the high seas, import or
export, deliver, receive, carry, transport, or ship in interstate or
foreign commerce in the course of a commercial activity, or to sell or
offer for sale in interstate or foreign commerce, any endangered
wildlife species. It also is illegal to possess, sell, deliver, carry,
transport, or ship any such wildlife that has been taken in violation
of the Act. Certain exceptions apply to agents of the Service and State
conservation agencies.
We may issue permits to carry out otherwise prohibited activities
involving threatened wildlife species under certain circumstances.
Regulations governing permits are codified at Sec. 17.32 for
threatened species. Such permits are available for scientific purposes,
to enhance the propagation or survival of the species and for
incidental takes in the course of otherwise lawful activities. For
threatened species, permits are also available for zoological
exhibition, educational purposes, and special purposes consistent with
the purposes of the Act.
Questions regarding whether specific activities will constitute a
violation of section 9 of the Act should be directed to the U.S. Fish
and Wildlife Service, North Florida Ecological Services Field Office
(see FOR FURTHER INFORMATION CONTACT section). Requests for copies of
the regulations regarding listed species and inquiries about
prohibitions and permits may be addressed to the U.S. Fish and Wildlife
Service, Ecological Services Division, 1875 Century Boulevard, Suite
200, Atlanta, GA 30345 (telephone 404-679-7313, facsimile 404-679-
7081).
Effects of This Rule
This final rule revises 50 CFR 17.11(h) to reclassify the U.S. wood
stork DPS from endangered to threatened on the List of Endangered and
Threatened Wildlife. This rule formally recognizes that the U.S. wood
stork DPS is no longer in danger of extinction throughout all or a
significant portion of its range. This reclassification does not
significantly change the protections afforded this species under the
Act. Based on new information about the range of the U.S. wood stork
DPS and where nesting is now occurring, this rule also revises 50 CFR
17.11(h) to reflect that the U.S. wood stork is a DPS and the range of
the U.S. wood stork DPS has expanded from Alabama, Florida, Georgia,
and South Carolina to also include North Carolina and Mississippi (see
Distinct Vertebrate Population Segment Analysis section).
The regulatory protections of section 9 and section 7 of the Act
will remain in place for the wood stork. Anyone taking, attempting to
take, or otherwise possessing a wood stork, or parts thereof, in
violation of section 9 of the Act is subject to a penalty under section
11 of the Act. Pursuant to section 7 of the Act, all Federal agencies
must ensure that any actions they authorize, fund, or carry out are not
likely to jeopardize the continued existence of the U.S. wood stork
DPS.
Recovery actions directed at the wood stork will continue to be
implemented as outlined in the recovery plan (Service 1997). Highest
priority recovery actions include: (1) Locate nesting habitat; (2)
locate roosting and foraging habitat; (3) inform landowners; (4)
protect (nesting) sites from disturbance; (5) use existing regulatory
mechanisms to protect habitat; and (6) monitor nesting and productivity
of stork populations.
[[Page 37103]]
Finalization of this rule does not constitute an irreversible
commitment on our part. Reclassification of the U.S. wood stork DPS
from threatened status to endangered status could occur if changes
occur in management, population status, or habitat, or if other factors
detrimentally affect the DPS or increase threats to the species'
survival. Such a reclassification would require another rulemaking.
Required Determinations
Paperwork Reduction Act of 1995
This rule does not contain any new collections of information that
require approval by the Office of Management and Budget (OMB) under the
Paperwork Reduction Act (44 U.S.C. 3501 et seq.). This rule will not
impose recordkeeping or reporting requirements on State or local
governments, individuals, businesses, or organizations. An agency may
not conduct or sponsor, and a person is not required to respond to, a
collection of information unless it displays a currently valid OMB
control number.
National Environmental Policy Act
We have determined that we do not need to prepare an environmental
assessment or environmental impact statement, as defined in the
National Environmental Policy Act of 1969 (42 U.S.C 4321 et seq.), in
connection with regulations adopted pursuant to section 4(a) of 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, and the Department
of the Interior Manual Chapter 512 DM 2, we have considered possible
effects on and have notified the Native American Tribes within the
range of the U.S. breeding population of the wood stork about this
rule. They have been advised through a written informational mailing
from the Service. If future activities resulting from this rule may
affect Tribal resources, a Plan of Cooperation will be developed with
the affected Tribe or Tribes.
References Cited
A complete list of references cited is available on the Internet at
http://www.regulations.gov and upon request from the North Florida
Ecological Services Field Office (see FOR FURTHER INFORMATION CONTACT).
Authors
The primary authors of this document are the staff members of the
North Florida Ecological Services Field Office (see FOR FURTHER
INFORMATION CONTACT).
List of Subjects in 50 CFR Part 17
Endangered and threatened species, Exports, Imports, Reporting and
recordkeeping requirements, Transportation.
Regulation Promulgation
We amend part 17, subchapter B of chapter I, title 50 of the Code
of Federal Regulations, as set forth below:
PART 17--[AMENDED]
0
1. The authority citation for part 17 continues to read as follows:
Authority: 16 U.S.C. 1361-1407; 16 U.S.C. 1531-1544; 16 U.S.C.
4201-4245; unless otherwise noted.
0
2. Amend Sec. 17.11(h) by revising the entry for ``Stork, wood'' under
``BIRDS'' in the List of Endangered and Threatened Wildlife to read as
follows:
Sec. 17.11 Endangered and threatened wildlife.
* * * * *
(h) * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Species Vertebrate
------------------------------------------------ population
Historic range where Status When listed Critical Special rules
Common name Scientific name endangered or habitat
threatened
--------------------------------------------------------------------------------------------------------------------------------------------------------
* * * * * * *
BIRDS
* * * * * * *
Stork, wood.................. Mycteria U.S.A. (CA, AZ, U.S.A. (AL, FL, T 142, 837 NA NA
americana. TX, to GA, MS, NC,
Carolinas), SC).
Mexico, C. and
S. America.
* * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
* * * * *
Date: May 23, 2014.
Daniel M. Ashe,
Director, U.S. Fish and Wildlife Service.
[FR Doc. 2014-14761 Filed 6-27-14; 8:45 am]
BILLING CODE 4310-55-P