[Federal Register Volume 88, Number 210 (Wednesday, November 1, 2023)]
[Rules and Regulations]
[Pages 74890-74907]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-24059]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[Docket No. FWS-R4-ES-2021-0058; FF09E22000 FXES1113090FEDR 234]
RIN 1018-BE53
Endangered and Threatened Wildlife and Plants; Reclassifying
Mitracarpus Polycladus From Endangered to Threatened With a Section
4(d) Rule
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Final rule.
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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), are
reclassifying Mitracarpus polycladus (a plant, no common name) from
endangered to threatened (downlist) under the Endangered Species Act of
1973, as amended (Act). This action is based on our evaluation of the
best available scientific and commercial information, which indicates
that the species' status has improved such that it is not currently in
danger of extinction throughout all or a significant portion of its
range, but that it is still likely to become so in the foreseeable
future. We are also finalizing a rule issued under section 4(d) of the
Act that provides for the conservation of the species.
DATES: This rule is effective December 1, 2023.
ADDRESSES: The proposed rule, this final rule, and supporting documents
are available at https://www.fws.gov/office/caribbean-ecological-services/library and at https://www.regulations.gov under Docket No.
FWS-R4-ES-2021-0058.
FOR FURTHER INFORMATION CONTACT: Edwin Mu[ntilde]iz, Field Supervisor,
U.S. Fish and Wildlife Service, Caribbean Ecological Services Field
Office, P.O. Box 491, Boquer[oacute]n, PR 00622; email:
[[Page 74891]]
[email protected]; telephone: (786) 244-0081. Individuals in the
United States who are deaf, deafblind, hard of hearing, or have a
speech disability may dial 711 (TTY, TDD, or TeleBraille) to access
telecommunications relay services. Individuals outside the United
States should use the relay services offered within their country to
make international calls to the point-of-contact in the United States.
SUPPLEMENTARY INFORMATION:
Executive Summary
Why we need to publish a rule. Under the Act, a species warrants
reclassification from endangered to threatened if it no longer meets
the definition of an endangered species (in danger of extinction
throughout all or a significant portion of its range). Mitracarpus
polycladus is listed as endangered, and we are reclassifying M.
polycladus as threatened (i.e., ``downlisting'' the species). We have
determined M. polycladus does not meet the Act's definition of an
endangered species, but it does meet the Act's definition of a
threatened species (likely to become an endangered species throughout
all or a significant portion of its range within the foreseeable
future). Reclassifying a species as a threatened species can be
completed only by issuing a rule through the Administrative Procedure
Act rulemaking process (5 U.S.C. 551 et seq.).
What this document does. This rule reclassifies Mitracarpus
polycladus from an endangered to a threatened species on the Federal
List of Endangered and Threatened Plants and establishes provisions
under section 4(d) of the Act that are necessary and advisable to
provide for the conservation of this species (a ``4(d) rule'').
The basis for our action. Under the Act, we may determine that a
species is an endangered or a threatened species because of any of five
factors: (A) The present or threatened destruction, modification, or
curtailment of its habitat or range; (B) overutilization for
commercial, recreational, scientific, or educational purposes; (C)
disease or predation; (D) the inadequacy of existing regulatory
mechanisms; or (E) other natural or manmade factors affecting its
continued existence. We may reclassify a species if the best available
commercial and scientific data indicate the species no longer meets the
applicable definition in the Act. Based on the status review, the
current threats analysis, and evaluation of conservation measures
discussed in this rule, we conclude that M. polycladus no longer meets
the Act's definition of an endangered species, and should be
reclassified to a threatened species. The species is no longer in
danger of extinction throughout all or a significant portion of its
range, but is likely to become so within the foreseeable future.
We have determined that Mitracarpus polycladus is a threatened
species due to the following threats: habitat destruction and
modification due to road and trail maintenance; trampling by humans;
human-caused fires; nonnative, invasive species; urbanization and
tourism development; grazing; and the effects of climate change.
Because we are reclassifying Mitracarpus polycladus as a threatened
species, we are also adopting a 4(d) rule to provide for the
conservation of this species.
Previous Federal Actions
Please refer to the June 23, 2022, proposed rule to reclassify
Mitracarpus polycladus (87 FR 37476) for a detailed description of
previous Federal actions concerning this species.
Peer Review
In accordance with our joint policy on peer review published in the
Federal Register on July 1, 1994 (59 FR 34270), and our August 22,
2016, memorandum updating and clarifying the role of peer review of
listing actions under the Act, we solicited independent scientific
opinions of the information contained in the June 23, 2022, proposed
rule to downlist Mitracarpus polycladus (87 FR 37476). We sent the
proposed rule to five independent peer reviewers and received one
response. The peer review can be found at https://www.regulations.gov.
In preparing the final rule, we incorporated the results of this
review, as appropriate, into this final rule. A summary of the peer
review comments and our responses can be found in the Summary of
Comments and Recommendations, below.
Summary of Changes From the Proposed Rule
In the preamble of the June 23, 2022, proposed rule (87 FR 37476 at
p. 37492), we describe our intention to propose to include all of the
general exceptions to the prohibition against removing and reducing to
possession, as set forth in 50 CFR 17.61, in the 4(d) rule for
Mitracarpus polycladus. This approach provides our Territorial partners
the ability to carry out conservation actions to benefit the species.
However, we neglected to include the exceptions set forth at 50 CFR
17.61(c)(2) and (3) in the regulatory text of our proposed rule. In
this final rule, we correct that oversight by adding these exceptions
to the regulatory text of the 4(d) rule for Mitracarpus polycladus.
This improves the 4(d) rule's clarity and accuracy, and makes it
consistent with our proposed rule's and this final rule's preamble
text.
In addition, in this final rule, we make minor, nonsubstantive
editorial or stylistic changes and corrections to the June 23, 2022,
proposed rule (87 FR 37476).
Summary of Comments and Recommendations
In the proposed rule published on June 23, 2022 (87 FR 37476), we
requested that all interested parties submit written comments on the
proposal by August 22, 2022. We also contacted appropriate Federal and
State agencies, scientific experts and organizations, and other
interested parties and invited them to comment on the proposal.
Newspaper notices announcing the proposed rule and inviting general
public comment were published in Spanish and English in the Primera
Hora newspaper. We did not receive any requests for a public hearing or
any public comments on the proposed rule.
Peer Reviewer Comments
As discussed in Peer Review, above, we received comments from one
peer reviewer on the proposed rule. We reviewed the peer reviewer's
comments for substantive issues and new information regarding the
information contained in the proposed rule. The peer reviewer generally
concurred with our methods and conclusions and provided additional
information, clarifications, and suggestions to improve the final rule.
The peer reviewer's comments are incorporated into this final rule as
appropriate.
Peer Reviewer Comments
(1) Comment: One peer reviewer provided additional references and
updated information and corrections about the Anegada Island population
including the following:
On Anegada Island, Mitracarpus polycladus occurs adjacent
to an unpaved road on Copper Rock leading to the beach and adjacent to
a road to Flash of Beauty, a popular tourist spot.
On Anegada Island, the population estimate is not
definitive, but described as decreased from historical. Where
Mitracarpus polycladus occurs adjacent to both sides of an unpaved road
in one locality, the reviewer concluded that more individuals likely
occurred between the two current clusters before the road was
constructed.
[[Page 74892]]
Our response: We revised our description of the location of
Mitracarpus polycladus on Anegada Island to reflect the occurrences
adjacent to roads or trails, the threat of road and trail maintenance
to those localities, and the impact of the road construction of the
population trend. We have incorporated the provided information into
our analysis in this final rule (see Summary of Biological Status and
Threats and Overall Summary of Factors Affecting the Species, below).
(2) Comment: One peer reviewer noted that grazing is a threat to
Mitracarpus polycladus on Anegada Island and suggested the threat of
grazing should be more strongly reflected in the rule.
Our response: We describe the negative impact of grazing on the
Anegada Island population in the proposed rule (87 FR 37476, June 23,
2022, at p. 37485) and under Habitat Destruction and Modification,
below. We agree that grazing on Anegada Island impacts the population,
and we more clearly describe the influence of grazing on habitat
destruction and modification in this final rule.
(3) Comment: One peer reviewer provided information that several
seed collections have been made from Anegada Island (most recently in
June 2022), which demonstrates that the individuals are reproducing.
The reviewer also noted that propagation efforts from plant material
from Anegada Island were lost in Hurricane Irma and a February 2022
germination trial was not successful.
Our response: We are encouraged to learn of seed collection efforts
and documented reproduction in the Anegada Island population. We have
incorporated the information provided by the reviewer regarding the
seed collection and propagation efforts into this final rule (see
Background, below). Recovery efforts for the species, including
propagation efforts, are ongoing and additional conservation actions
including propagation and transplantation of M. polycladus will
hopefully support recovery of the species in the future. We do
recognize the challenges in propagation of Mitracarpus; thus, we did
not rely on seed collection or propagation efforts in our status
determination. Although the loss of propagated material and failure of
the germination trial is unfortunate, the setback of this portion of
the recovery effort does not change the species' rangewide condition or
our determination that the species meets the definition of a threatened
species and should be reclassified.
(4) Comment: One peer reviewer questioned the catastrophic impact
of storm surge as an effect of climate change on the Mitracarpus
polycladus that occur near the coast.
Our response: We describe the impact of sea level rise and the
effects of climate change on the species in the proposed rule (87 FR
37476, June 23, 2022, at pp. 37485-37486) and under Effects of Climate
Change and Sea Level Rise, below. We expect the impact to the species
from storm surge to be shorter-term compared to the effect of sea level
rise as it relates to saltwater exposure. Mitracarpus polycladus occurs
in areas affected by storm surge from past and recent hurricanes and,
as an island species, does not appear to be negatively affected by
short-term exposure to saltwater as a result of storm surge and
hurricanes. Although some individuals in low-lying areas may be
affected by increasing exposure to saltwater for more prolonged periods
in the future, we have determined this threat does not affect
Mitracarpus polycladus at the species level.
I. Reclassification Determination
Background
A thorough review of the taxonomy, life history, ecology, and
overall viability of Mitracarpus polycladus was presented in the 5-year
status reviews (Service 2011, entire; Service 2018a, entire) and the
June 23, 2022, proposed rule (87 FR 37476). Below, we present a summary
of the biological and distributional information for Mitracarpus
polycladus. Please refer to the 5-year reviews and proposed rule for
more detailed information.
Taxonomy and Species Description
Mitracarpus polycladus is a small shrub in the Rubiaceae (coffee)
family and the Spermacoce clade (Bremer 1996, p. 23). Mitracarpus
polycladus was first collected in Puerto Rico in 1886, and was
described in 1903 as a new species (Urban 1903, p. 389; Lioger 1997, p.
124). The taxonomy of the species has not changed since first
described. Individuals of this plant species may reach up to 45
centimeters (cm) (17.7 inches (in)) in height, and its stems grow
either erect or along the ground (Proctor 1991, p. 127; Lioger 1997, p.
125). The leaves are smooth and narrow, and the inflorescence is made
up of smaller white flowers. The seed capsule is very small (1.5
millimeter (mm) (0.06 in) diameter) and contains black seeds (Proctor
1991, p. 127).
Biology
Mitracarpus polycladus colonizes exposed limestone where
aggregations of sediment and water provide necessary conditions for
seed germination and seedling rooting (Medina et al. 2012, p. 203). The
phenology of M. polycladus is closely related to the dry and rainy
seasons. Flower production occurs just after the peak of rainfall,
which may start as early as May and end as late as December, and seed
availability occurs during the dry season, which is December to March
(Service 2018a, p. 8). The species shows a large reproductive output
(high number of seedlings) after the rainy season followed by a low
number of mature adults present during the next rainy season. Seed
germination has been observed a few days after a rain event, producing
numerous seedlings surrounding mature plants, denoting a clumped
spatial distribution (Service 2018b, p. 6). The timing and spatial
distribution of seedlings indicate the species produces viable seeds
that stay in the soil seedbank until the next rain event (Service
2018b, p. 6).
Although a large number of seedlings (e.g., 1,500 and 13,680 in
2011 and 2018, respectively) have been documented in Puerto Rico,
seedling estimates are not included as part of the population abundance
estimates because surveyors have been unable to determine seedling
survival rates and effective recruitment (Service 2011, p. 24; Service
2018b, p. 8). High mortality of seedlings is observed due to natural
thinning of the seedlings and environmental variables (drought stress)
(Service 2018b, p. 8). Experts conclude that seeds are dependent on
water or wind as a dispersal mechanism, with seeds that are not
dispersed by water or wind clumping near the mature plant (Buitrago-
Soto 2002, p. 25; Service 2018a, p. 9).
Little information is available regarding Mitracarpus polycladus's
pollinators. However, two insect groups (Hymenoptera and Lepidoptera)
have been identified as visiting M. polycladus flowers and may act as
effective pollinators of the species (Monsegur 2017, unpublished data).
The observations of multiple insect groups visiting M. polycladus
support our rationale for defining localities in the Gu[aacute]nica
Commonwealth Forest (GCF) area as a single population, as available
information indicates the species is cross-pollinated by insects. We
expect insect-facilitated cross-pollination is taking place among GCF
localities.
[[Page 74893]]
Distribution and Abundance
Mitracarpus polycladus was known to occur only in Puerto Rico and
on Saba Island (a municipality of the Netherlands) in the Lesser
Antilles at the time of listing (59 FR 46715; September 9, 1994).
Although the species was discovered on Anegada Island (British Virgin
Islands) in 1970, we were not aware of this occurrence at the time of
listing (Service 2011, p. 9; Hamilton and B[aacute]rrios 2017, p. 1).
When listed, Mitracarpus polycladus was known in Puerto Rico only
from the Mesetas trail in the GCF (DNR 1976, pp. 56-58; 59 FR 46715,
September 9, 1994). No abundance estimates were available for the
species in Puerto Rico, and no information was available on the status
of the species on Saba Island. When the 1998 recovery plan was
finalized, there was little information on M. polycladus's historical
and current abundance, distribution, ecology, and reproductive biology.
At that time, we described M. polycladus occurrences in Puerto Rico and
Saba Island as two populations (Proctor 1991, p. 2; Service 1998, p.
2).
At the time of listing and in the subsequent 5-year status reviews,
occurrences of Mitracarpus polycladus in Puerto Rico were referred to
as localities, and the occurrences on Anegada and Saba Islands were
referred to as populations due to their distant geographic location.
This approach did not consider the species-specific characteristics of
clumped spatial distribution, distance among localities, natural
geographic barriers, or the species' life-history requirement for
cross-pollination. We now have additional information about M.
polycladus's geographic and spatial distribution and biological and
ecological aspects of the species' life history (e.g., pollinators,
seed dispersion, phenology). This information indicates the following
natural physical barriers preclude cross-pollination among populations
and localities: coastal plains; dense, extensive forest patches; and
bays. We also determined that connectivity among localities is required
to maximize the likelihood of cross-pollination and gene flow, and to
increase fruit production, viable seeds, and natural recruitment to
support M. polycladus populations.
We now identify three natural populations of M. polycladus: (1)
Gu[aacute]nica forest in south Puerto Rico (composed of at least 10
localities within the GCF, which is managed for M. polycladus
conservation, and adjacent lands that provide suitable habitat and
connectivity); (2) Saba Island; and (3) Anegada Island. A separate
locality, Cerro Toro, was established as a private translocation
effort. This population is disjunct (no connectivity nor cross-
pollination) from the GCF population; thus, we determined it is a
separate, introduced population.
Since the time of listing and the recovery plan development,
targeted surveys have provided new abundance and distribution
information and incidental observations (see table 1, below) (Service
2007 and 2017, unpublished data). The most recent survey information
(see table 2, below) may underestimate population abundance and spatial
extent as it did not include three natural localities due to time
constraints. Because changes in the habitat have not been observed in
the three localities not surveyed, we expect the abundance (number) and
spatial extent (hectares (ha)) to be similar to the previous
assessments. Therefore, the information from these three localities is
unlikely to substantially change the estimates of abundance and extent
of occupied area for the population. The increase in the number of
localities recorded in Puerto Rico reflects additional survey efforts
since the time of listing, while the increase in the number of
individuals likely reflects the species' seasonal reproductive response
to rain events and timing of surveys (Service 2018b, p. 3).
Table 1--Abundance and Distribution Information for Mitracarpus Polycladus in the Gu[aacute]nica Commonwealth
Forest in Puerto Rico Since 2011
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Abundance (# Area occupied
Year Number of of adult in hectares/ Source
localities plants) acres
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2011.................................. 7 * 1,400 n/a Service 2011, pp. 8, 14.
2018.................................. 9 12,472 0.42/1.02 Service 2018, p. 22.
2018.................................. 10 17,637 0.44/1.1 Service 2018b, p. 9.
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* Includes only 4 localities.
In the Puerto Rico population, we are aware of 10 natural
localities and 1 introduced locality; 8 natural localities occur in the
GCF, and 3 are on private properties (Ballena Beach, Cerro Toro, and
Monte de la Ventana, which extends into the GCF) (see table 2, below).
We have identified additional potentially suitable habitat for the
species, including appropriate vegetation structure and presence of
exposed limestone, in aerial images of the GCF. However, this habitat
has not been quantified or surveyed, and it is unknown if the species
occurs there (Service 2018b, p. 8).
Table 2--Current Abundance and Areal Extent of Mitracarpus Polycladus at Known Localities in Puerto Rico
[Service 2018b, p. 9]
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Area occupied
Locality name Abundance (# of adult plants) in hectares/ Ownership
acres
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Ca[ntilde]a Gorda.................. Undetermined........................ .............. Puerto Rico
Department of
Natural and
Environmental
Resources
(Department).
Jaboncillo......................... Undetermined........................ .............. Department.
Mesetas Trail...................... 13,064.............................. 0.255/0.63 Department.
Ballena Trail...................... 1,048............................... 0.036/0.09
[[Page 74894]]
La Cueva........................... 310................................. 0.016/0.04
Hoya Honda......................... 246................................. 0.004/0.01
State road PR 333.................. 653................................. 0.028/0.07
Las Picuas......................... 336................................. 0.024/0.06
Monte de la Ventana................ 1,967............................... 0.077/0.19 Department and
Private.
Ballena Beach...................... Undetermined........................ .............. Private.
Cerro Toro......................... 13.................................. 0.004/0.01 Private.
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Total:......................... 17,637.............................. 0.44/1.1 .....................
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On Saba Island, the best available information indicates the
species occurs in several localities along the road between The Bottom
and Windward Side towns in the southern section of the island (Rojer
1997, p. 19). No current population estimate is available for Saba
Island, and the 1997 assessment does not include a population estimate.
On Anegada Island, surveys for Mitracarpus polycladus were conducted in
2015, 2016, and 2017, with an estimated population of 2,500 individuals
in the north-central region of the island between Windlass Point and
Cooper Rock (B[aacute]rrios and Hamilton 2018, pp. 3-4).
Habitat
Throughout its range in Puerto Rico, Mitracarpus polycladus occurs
only on exposed limestone with sediment and water accumulation in holes
and crevices. The species is restricted to geographical areas with
unique substrate and climate features in dry forest habitat types that
serve as corridors for pollinators and facilitate cross-pollination
among M. polycladus localities within contiguous habitats. The species
occurs among three major types of plant communities: coastal shrub
forest, cactus scrub forest, and coastal scrub on sandy soil (DNR 1976,
p. 53; Lugo et al. 1978, p. 282; Service 2018b, p. 11). Although these
three plant communities occur on approximately 15 percent of the GCF,
known occurrences of M. polycladus occupy a small total area (0.44 ha
(1.1 ac)) where habitat and microhabitat features (i.e., exposed
limestone and aggregation of sediment and water) essential for the
species are present (Service 2018b, p. 8; see table 2, above). However,
surveys have not been conducted throughout the suitable forest types;
thus, the species may occur elsewhere within this area. All known M.
polycladus localities in Puerto Rico fall in the subtropical dry forest
life zone. This life zone occupies an area of 121,640 ha (300,576 ac)
(Ewel and Whitmore 1973, p. 9) and is the driest life zone in Puerto
Rico. It receives a mean annual rainfall of 60-100 cm (24-40 in),
experiences high temperatures, and has high evapotranspiration when
sufficient water is available (Murphy and Lugo 1986, p. 90;
C[aacute]ceres-Charneco 2018, p. 27). The climate in this region is
seasonal, with most precipitation occurring in September and October
(Lugo et al. 1978, p. 278) and another small peak of rainfall in May
and June (Sloan et al. 2006, p. 196; C[aacute]ceres-Charneco 2018, p.
28).
On Saba Island, the best available information indicates the
species occurs on Gile's cherty sandy loam soil found between The
Bottom and Windward Side towns. This arid section of the island is
located in the south portion of Saba Island (Rojer 1997, p. 19; Freitas
et al. 2016, p. 10). On Anegada Island, Mitracarpus polycladus
currently grows on limestone plain and coastal sandy habitats located
in the north-central area of this island where the species is
restricted to two localities situated between Windlass Point and Cooper
Rock (B[aacute]rrios and Hamilton 2018, p. 4). This area on Anegada
Island has similar environmental conditions and soil characteristics to
M. polycladus localities in Puerto Rico.
Recovery Criteria
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. Under section 4(f)(1)(B)(ii),
recovery plans must, to the maximum extent practicable, include
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 Lists of Endangered and
Threatened Wildlife and Plants.
Recovery plans provide a roadmap for us and our partners on methods
of enhancing conservation and minimizing threats to listed species, as
well as measurable criteria against which to evaluate progress towards
recovery and assess the species' likely future condition. However, they
are not regulatory documents and do not substitute for the
determinations and promulgation of regulations required under section
4(a)(1) of the Act. A decision to revise the status of a species, or to
delist a species, is ultimately based on an analysis of the best
scientific and commercial data available to determine whether a species
is no longer an endangered species or a threatened species, regardless
of whether that information differs from the recovery plan.
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 be exceeded while other criteria may
not yet be accomplished. In that instance, we may determine that the
threats are minimized sufficiently and that the species is robust
enough that it no longer meets the Act's definition of an endangered
species or threatened species. In other cases, we may discover new
recovery opportunities after having finalized the recovery plan.
Parties seeking to conserve the species may use these opportunities
instead of methods identified in the recovery plan. Likewise, we may
learn new information about the species after we finalize the recovery
plan. The new information may change the extent to which existing
criteria are appropriate for identifying recovery of the species. The
recovery of a species is a dynamic
[[Page 74895]]
process requiring adaptive management that may, or may not, follow all
of the guidance provided in a recovery plan.
The initial recovery plan does not provide delisting criteria;
however, the revised recovery plan provides three criteria for
delisting Mitracarpus polycladus (Service 1998, p. 8; Service 2019, p.
4). The three delisting criteria outlined in the revised recovery plan
are: (1) Threat reduction and management activities have been
implemented to a degree that the species will remain viable into the
foreseeable future; (2) existing natural populations of M. polycladus
show a stable or increasing trend, as evidenced by natural recruitment
and multiple age classes; and (3) within the historical range, at least
three new populations of M. polycladus showing a stable or increasing
trend have been established on lands protected by conservation
measures, as evidenced by natural recruitment and multiple age classes
(Service 2019, entire). Based on the information gathered and analyzed,
two of these criteria have been partially met and the third has been
initiated. The following discussion provides an assessment of the
delisting criteria as they relate to evaluating the status of M.
polycladus.
Criterion 1 for Delisting
Criterion 1 states that threat reduction and management activities
have been implemented to a degree that the species will remain viable
into the foreseeable future. Eighty-nine percent of the currently known
Mitracarpus polycladus in Puerto Rico occur within the GCF, which is
managed for conservation by the Puerto Rico Department of Natural and
Environmental Resources (Department) (DNR 1976, p. 56). The management
actions in the GCF protect M. polycladus from development activities
and are compatible with the species' needs. The Department lists the
species as critically endangered and reviews all proposed actions in
the GCF that may impact M. polycladus or its habitat (DNRNA 2004, p.
52). The species is also impacted by road maintenance activities
(vegetation trimming) in 5 of the 11 localities where the species
occurs in Puerto Rico (4 of these localities are within the GCF)
(Service 2018b, p. 10). Each of the localities in the GCF has
experienced habitat destruction or modification from one or more
threats, including intense trail use, human-caused fires, nonnative and
invasive species encroachment, and road maintenance. However, the
threats have been reduced, and the protected and managed habitat in the
GCF remains a stronghold for the species with the largest number of
individuals and areal extent occurring along the Mesetas trail. Thus,
although M. polycladus is legally protected in this forest, it is
subject to actions that limit its abundance and distribution in
impacted areas. Two localities on private lands are subject to
potential development pressure as discussed under ``Urbanization and
Development,'' below.
Evidence of fire has been recorded on or adjacent to two
Mitracarpus polycladus localities (Service 2018a, p. 27). The species
does not colonize previously burned areas; therefore, fire can be a
threat to species viability, as M. polycladus is endemic to dry
limestone forest where vegetation did not evolve under a natural fire
regime (Service 2018b, p. 12).
These threats of fire, development, nonnative and invasive species,
and road and trail maintenance, coupled with competition with other
plant species for specific habitat requirements such as holes and
cracks for seed germination, and observed lack of dispersal mechanisms,
reduce the species' ability to colonize other areas. Therefore, we
determined that, while threat reduction and management activities at
GCF have been implemented and have improved the species' viability,
they have not been implemented or improved viability to a degree that
the species will maintain viability into the foreseeable future. Thus,
we conclude that this criterion has been partially met.
Criterion 2 for Delisting
Criterion 2 states that existing natural populations of Mitracarpus
polycladus show a stable or increasing trend, as evidenced by natural
recruitment and multiple age classes. Since the time of listing, the
number of individuals and localities reported for M. polycladus have
increased. Approximately 17,624 adult M. polycladus individuals are
currently distributed in 10 natural localities in Puerto Rico occupying
0.44 ha (1.1 ac), with documented recruitment as evidenced by numerous
seedlings in close proximity to adult plants, particularly after rain
events. However, existing data indicate that seedlings' survival is
uncertain due to natural thinning and environmental stochasticity
(drought stress). However, effective recruitment has occurred, and
seedlings and saplings were noted in seven of eight localities with
abundance, seedling, and sapling counts in Puerto Rico during the 2018
assessment (Service 2018b, p. 9). Habitat modification caused by human-
caused fires and subsequent encroachment of nonnative grasses has
resulted in the loss of some clusters of individuals within a locality.
Habitat modification and other threats, discussed below under Summary
of Biological Status and Threats, may preclude the expansion of the
species within known suitable habitats in Puerto Rico. The population
trend on Anegada Island has been described as decreasing due to the
removal of some individuals in one locality from past road
construction. Seed collections have occurred recently in the Anegada
Island population, indicating reproduction, although the level of
recruitment in that population is unknown (B[aacute]rrios 2023, pers.
comm.). The status and trend of the M. polycladus population on Saba
Island, including reproduction and recruitment, is currently unknown.
Based on the uncertainty of population estimates and the lack of
evidence of expansion into suitable habitat, we determined that a
stable or increasing trend, as evidenced by natural recruitment and
multiple age classes, has been met in Puerto Rico, but not on Saba or
Anegada Islands. Thus, we conclude that this criterion has been
partially met.
Criterion 3 for Delisting
Criterion 3 states that at least three new populations of
Mitracarpus polycladus showing a stable or increasing trend have been
established within the historical range on lands protected by
conservation, as evidenced by natural recruitment and multiple age
classes. In Cerro Toro, an undetermined number of M. polycladus
individuals were translocated from the Monte de la Ventana locality by
the landowner to establish a new population of the species physically
separated from the GCF population. As of 2018, 13 of the planted
individuals were still alive (Service 2018b, p. 9; see table 2, above),
but no recruitment (seedlings or saplings) was observed. However, this
recovery effort has not been expanded. The Royal Botanic Gardens (Kew),
in collaboration with the National Park Trust of the Virgin Islands,
has made effort to propagate material from M. polycladus on Anegada
Island, but no planting efforts have been implemented. No further
efforts of translocations or propagation and reintroduction are
currently known. To increase the species' redundancy and long-term
viability, additional populations should be established through
translocation and/or propagation throughout the species' range. Thus,
we conclude that this criterion has been initiated, but not met.
[[Page 74896]]
Regulatory and Analytical Framework
Regulatory Framework
Section 4 of the Act (16 U.S.C. 1533) and the implementing
regulations in title 50 of the Code of Federal Regulations set forth
the procedures for determining whether a species is an endangered
species or a threatened species, issuing protective regulations for
threatened species, and designating critical habitat for endangered and
threatened species. In 2019, jointly with the National Marine Fisheries
Service, the Service issued a final rule that revised the regulations
in 50 CFR part 424 regarding how we add, remove, and reclassify
endangered and threatened species and the criteria for designating
listed species' critical habitat (84 FR 45020; August 27, 2019). On the
same day, the Service also issued final regulations that, for species
listed as threatened species after September 26, 2019, eliminated the
Service's general protective regulations automatically applying to
threatened species the prohibitions that section 9 of the Act applies
to endangered species (84 FR 44753; August 27, 2019).
The Act defines an ``endangered species'' as a species that is in
danger of extinction throughout all or a significant portion of its
range, and a ``threatened species'' as a species that is likely to
become an endangered species within the foreseeable future throughout
all or a significant portion of its range. The Act requires that we
determine whether any species is an endangered species or a threatened
species because of any of the following factors:
(A) The present or threatened destruction, modification, or
curtailment of its habitat or range;
(B) Overutilization for commercial, recreational, scientific, or
educational purposes;
(C) Disease or predation;
(D) The inadequacy of existing regulatory mechanisms; or
(E) Other natural or manmade factors affecting its continued
existence.
These factors represent broad categories of natural or human-caused
actions or conditions that could have an effect on a species' continued
existence. In evaluating these actions and conditions, we look for
those that may have a negative effect on individuals of the species, as
well as other actions or conditions that may ameliorate any negative
effects or may have positive effects. We consider these same five
factors in downlisting a species from endangered to threatened.
We use the term ``threat'' to refer in general to actions or
conditions that are known to or are reasonably likely to negatively
affect individuals of a species. The term ``threat'' includes actions
or conditions that have a direct impact on individuals (direct
impacts), as well as those that affect individuals through alteration
of their habitat or required resources (stressors). The term ``threat''
may encompass--either together or separately--the source of the action
or condition or the action or condition itself.
However, the mere identification of any threat(s) does not
necessarily mean that the species meets the statutory definition of an
``endangered species'' or a ``threatened species.'' In determining
whether a species meets either definition, we must evaluate all
identified threats by considering the species' expected response by and
the effects of the threats--in light of those actions and conditions
that will ameliorate the threats--on an individual, population, and
species level. We evaluate each threat and its expected effects on the
species, then analyze the cumulative effect of all of the threats on
the species as a whole. We also consider the cumulative effect of the
threats in light of those actions and conditions that will have
positive effects on the species--such as any existing regulatory
mechanisms or conservation efforts. The Secretary of the Interior
(Secretary) determines whether the species meets the definition of an
``endangered species'' or a ``threatened species'' only after
conducting this cumulative analysis and describing the expected effect
on the species now and in the foreseeable future.
The Act does not define the term ``foreseeable future,'' which
appears in the statutory definition of ``threatened species.'' Our
implementing regulations at 50 CFR 424.11(d) set forth a framework for
evaluating the foreseeable future on a case-by-case basis. The term
``foreseeable future'' extends only so far into the future as we can
reasonably determine that both the future threats and the species'
responses to those threats are likely. In other words, the foreseeable
future is the period of time in which we can make reliable predictions.
``Reliable'' does not mean ``certain''; it means sufficient to provide
a reasonable degree of confidence in the prediction. Thus, a prediction
is reliable if it is reasonable to depend on it when making decisions.
It is not always possible or necessary to define foreseeable future
as a particular number of years. Analysis of the foreseeable future
uses the best scientific and commercial data available and should
consider the timeframes applicable to the relevant threats and to the
species' likely responses to those threats in view of its life-history
characteristics. Data that are typically relevant to assessing the
species' biological response include species-specific factors such as
lifespan, reproductive rates or productivity, certain behaviors, and
other demographic factors.
Analytical Framework
To assess Mitracarpus polycladus viability, we used the three
conservation biology principles of resiliency, redundancy, and
representation (Shaffer and Stein 2000, pp. 306-310). Briefly,
resiliency is the ability of the species to withstand environmental and
demographic stochasticity (for example, wet or dry, warm or cold
years); redundancy is the ability of the species to withstand
catastrophic events (for example, droughts, large pollution events);
and representation is the ability of the species to adapt to both near-
term and long-term changes in the physical and biological environment
(for example, climate conditions, pathogens). In general, species
viability will increase with increases in resiliency, redundancy, and
representation (Smith et al. 2018, p. 306). Using these principles, we
identified the species' ecological requirements for survival and
reproduction at the individual, population, and species levels, and
described the beneficial and risk factors influencing the species'
viability.
Summary of Biological Status and Threats
In this discussion, we review the biological condition of the
species and its resources, and the threats that influence the species'
current and future condition, in order to assess the species' overall
viability and the risks to that viability. In addition, the 5-year
reviews (Service 2011, entire; Service 2018a, entire) and our proposed
rule (87 FR 37476; June 23, 2022) document our comprehensive biological
status review for the species, including an assessment of the potential
threats to the species.
The following is a summary of these status reviews and the best
available information gathered since that time that have informed this
decision. For additional information and details regarding the current,
ongoing, and future threats to the species, see the June 23, 2022,
proposed rule (87 FR 37476).
Habitat Destruction and Modification
Habitat destruction and modification were identified as factors
affecting the continued existence of Mitracarpus
[[Page 74897]]
polycladus at the time of listing (59 FR 46715; September 9, 1994).
Road and trail maintenance, human-caused fire, nonnative and invasive
species, urbanization and tourism development, and grazing continue to
contribute to the destruction and modification of M. polycladus habitat
and are summarized below. Although changes to habitat conditions may
affect pollinator abundance and distribution, available information
does not indicate that a loss of pollinators is occurring in M.
polycladus habitat, and we expect that sufficient pollinators are
present to cross-pollinate within the pollinator's flight distance.
Roads and Trails Maintenance
Currently, in Puerto Rico, Mitracarpus polycladus occurs adjacent
to or along paved and unpaved roads, parking areas, and trails that
provide access to recreational areas in seven localities in the dry
southern section of the GCF (Service 2018b, p. 5). These roads and
trails are managed by the Department as scenic trails and natural
areas. However, management and maintenance activities, primarily
vegetation trimming, have affected M. polycladus individuals in these
areas (Service 2018b, p. 10). Similarly, the Puerto Rico Department of
Transportation and Public Works right-of-way maintenance causes impacts
to individuals and habitat in the State Road PR 333 locality (Service
2018b, p. 10). Right-of-way maintenance activities have resulted in
mortality of reproductive M. polycladus individuals in three localities
and may reduce production of seeds and potential seedlings in these
localities if the plants do not recover sufficiently to reproduce when
conditions are suitable (Service 2018b, p. 10).
The largest known Mitracarpus polycladus cluster occurs adjacent to
the heavily used Mesetas trail in GCF with 13,064 individuals occupying
an area of 0.255 ha (0.63 ac). Approximately 25 to 30 percent of M.
polycladus along the trail in this locality are exposed to damage
caused by trail maintenance and human trampling (Service 2018b, pp. 10-
11). Physical impacts to M. polycladus and its habitat are caused by
the frequent use of the scenic trails and adjacent habitat in the GCF
by residents and tourists for recreational activities (i.e., hiking,
running, and mountain biking) throughout the year (Service 2018a, p.
12).
Nonnative grass encroachment along trails follows a similar pattern
to encroachment following fire and is described below. The Anegada
Island population occurs adjacent to two trails or roads, and the
species occurs along roads and trails in Puerto Rico. However, we
expect that the effects of road and trail maintenance on the M.
polycladus populations are limited to a small number of individuals
closest to the road or trail edge. Although over half of localities and
several thousand individuals are exposed to the threat of road and
trail maintenance, available information indicates that this threat
does not have a population-level or species-level impact.
Human-Caused Fire
Fires are not a natural event in the subtropical dry forests in
Puerto Rico, and the native vegetation in the Caribbean is not adapted
to this type of disturbance (Brandeis and Woodall 2008, p. 557;
Santiago-Garc[iacute]a et al. 2008, p. 604). Human-caused fires were
identified as a threat to the species when listed (59 FR 46715;
September 9, 1994) and continue to occur throughout Mitracarpus
polycladus habitat in Puerto Rico (Service 2018a, p. 27). Currently, 6
of 10 natural localities of M. polycladus occur in areas vulnerable to
or at high risk of human-caused fires, particularly during the dry
season (Service 2018b, p. 10). Although the Department implements a
fire prevention and management program in the GCF during the dry
season, fires still occur and impact M. polycladus and its habitat
(Service 2018b, p. 11).
Fire affects Mitracarpus polycladus survival through impacts of
heat and encroachment of nonnative, invasive plant species. Nonnative
plant species outcompete M. polycladus and serve as fuel for fires
(Garc[iacute]a-Cancel 2013, pp. 19, 33; Service 2018a, p. 27). The
interaction of fire and nonnative species is described under
``Nonnative, Invasive Species,'' below. Moreover, M. polycladus does
not grow in areas with visible evidence of past fires (Service 2018b,
p. 11). This is likely due to destruction or loss of the seedbank,
precluding species germination and recolonization of an area from the
seedbank after a fire.
Fires destroy or reduce native vegetation through direct impacts to
individuals and to the seedbank (which is not fire-adapted) (Wolfe
2009, p. 28). Fires reduce or eliminate Mitracarpus polycladus seeds in
the seedbank and promote favorable conditions for the establishment of
nonnative, invasive plant species. These species, such as guinea grass
(Megathyrsus maximus), paj[oacute]n grass (Dichanthium annulatum), and
buffel grass (Cenchrus ciliaris), are adapted to a natural fire regime
and serve as fuel for fires, thus promoting conditions for a more
frequent fire regime that precludes the establishment of native
vegetation, including M. polycladus (Thaxton et al. 2012, p. 9). This
pattern occurs in M. polycladus habitat in the GCF, where nonnative
grasses are present and M. polycladus is not observed (Garc[iacute]a-
Cancel 2013, entire; Service 2018b, p. 12). Other factors such as seed
predation, seed intrinsic viability, and seedling survival also affect
forest recovery after fire. In M. polycladus habitat, fires promote
habitat fragmentation, return habitat to an earlier successional state,
and slow forest recovery processes (Brandeis and Woodall 2008, p. 557;
Meddens et al. 2008, p. 569).
Fire negatively impacts Mitracarpus polycladus and its habitat, and
the capacity of the species to recover from catastrophic fire events is
unknown. Moreover, M. polycladus occurs in areas with high
vulnerability to fires, exacerbating the potential effects of fire on
individuals and populations. The effects of climate change and
nonnative, invasive species may alter conditions in M. polycladus
habitat to promote increased susceptibility to fire (as described under
``Nonnative, Invasive Species,'' below). Therefore, even with the
Department's current fire prevention and management program efforts
during the dry season, human-caused fires occur every year within the
species' range. Fires in M. polycladus localities affect the survival
and recruitment of individuals, population resiliency, and,
potentially, the species' viability (Service 2018b, p. 11). Information
regarding the threat of fire to the Anegada and Saba Island populations
is less extensive than the information for Puerto Rico; however, we
expect the threat of human-caused fire is similar since the Anegada and
Saba Island populations also occur along roadsides.
Nonnative, Invasive Species
Caribbean dry forests generally have seedbanks with low numbers and
variety of species, and forest regeneration in areas disturbed through
mechanical vegetation removal or through burning is largely dependent
on propagules or seeds from nearby habitats (Wolfe 2009, p. 28).
Nonnative species typically become established more quickly and may
have less specific habitat or life-history requirements than native
species. When nonnative species become established in a disturbed
habitat, they outcompete native species for resources, including space,
nutrients, water, and sunlight. The impacts of nonnative, invasive
species are second only to habitat destruction and modification and are
among the greatest threats to the persistence of
[[Page 74898]]
native rare species and their habitats in Puerto Rico (Thomson 2005, p.
615; Garc[iacute]a-Cancel 2013, entire). Nonnative species like guinea
grass, buffel grass, paj[oacute]n grass, and African grass (Heteropogon
contortus) aggressively colonize and compete with native species for
sunlight, nutrients, water, and ground cover (space), suppressing
native vegetation (Garc[iacute]a-Cancel 2013, entire; Rojas-Sandoval
and Mel[eacute]ndez-Ackerman 2016, p. 156; Service 2018b, p. 12). In
addition, M. polycladus does not occur in areas occupied (or dominated)
by nonnative grasses at localities in the GCF (Garc[iacute]a-Cancel
2013, entire; Service 2018b, p. 12). Nonnative trees (e.g., lead tree
(Leucaena leucocephala)) also colonize M. polycladus habitat,
particularly after fire events, and suppress the growth of native
vegetation (Wolfe and Van Bloem 2012, entire).
In areas where Mitracarpus polycladus is established, nonnative
species do not appear to reduce habitat directly by displacing existing
M. polycladus individuals, but primarily impact populations by
preventing or reducing colonization by the species when the area is
disturbed. In summary, nonnative invasive species outcompete M.
polycladus for required resources, promote increased frequency and
intensity of fire, and prevent establishment of seedlings, thus
impacting M. polycladus at the individual, population, and,
potentially, species levels.
Urbanization and Development
One Mitracarpus polycladus locality occurs within the project area
of a proposed wind generation project (San Francisco Wind Farm) in
Monte de la Ventana. This project occupies 79 ha (195 ac) of dry forest
habitat with 1,967 M. polycladus individuals in the project area
(Service 2018b, pp. 1, 11). Ninety-six percent of M. polycladus
individuals on the site occur on and adjacent to now-abandoned roads
accessing the site. The wind farm construction project is covered by an
incidental take permit under a habitat conservation plan (HCP) that
includes conservation measures to minimize adverse effects to listed
species in the project area (Service 2013, p. 3). Although a
substantial portion of this property is identified as a conservation
area under the HCP, the conservation areas do not include habitat for
M. polycladus (Service 2013, p. 3). The species grows in open areas
(e.g., dirt roads and wind turbine pads in the project area) where it
is vulnerable to effects from the project's operations, including
impacts from maintenance activities, vehicle traffic, and habitat
encroachment by nonnative, invasive plants. To date, this wind farm
project has not been constructed, but we have no indication that the
project is abandoned.
The Ballena beach locality has been subject to development pressure
in the past with proposals for the development of a hotel in that area.
Although this hotel development project has not been constructed, it
may be pursued in the future.
Mitracarpus polycladus occurrences on Anegada and Saba Islands are
also threatened by development. On Anegada Island, in the British
Virgin Islands, the potential for island-wide development exists, with
local community support and road improvement works underway (Hamilton
2016, p. 185). Anegada Island has been recognized by its government as
an undeveloped island with high potential for tourism development due
to the beauty of its natural resources (sandy beaches and coral reefs).
In 2007, the Government of Anegada developed a land use plan (Plan)
designating areas for commercial and residential purposes, hotel
development, agriculture, community parks and recreational areas, a
business district, protection and conservation, and government offices
and related facilities (Island Resources Foundation (IRF) 2013, p. 24).
The Plan proposes to set aside some areas for conservation (IRF 2013,
p. 25); however, the proposed areas do not contain M. polycladus or its
habitat. If the Plan is enacted fully, we expect M. polycladus and its
habitat to be reduced or eliminated by the proposed development of the
island. Although urbanization and development plans for Saba Island (a
municipality of the Netherlands) are unknown, the potential for
urbanization and tourism development is present.
Grazing
On Anegada and Saba Islands, Mitracarpus polycladus habitat has
been degraded by the grazing of feral livestock, such as goats and
donkeys (Freitas et al. 2016, p. 21; B[aacute]rrios and Hamilton 2018,
p. 5; Hamilton 2020, pers. comm.). Livestock presence and grazing leads
to an increase in soil erosion while foraging, as observed on Saba
Island (Freitas et al. 2016, p. 21). These animals also trample M.
polycladus individuals, reduce its abundance, and affect the population
structure. The best available information indicates feral livestock
grazing may currently impact the Anegada and Saba Island populations.
In summary, impacts associated with habitat destruction and
modification due to vegetation clearance for maintenance and
improvement activities of roads and trails, urbanization and tourism
development, human-caused fires, and encroachment of nonnative plant
species have been documented as current and ongoing threats to
Mitracarpus polycladus throughout its range. In Puerto Rico, although
about 89 percent of M. polycladus individuals occur within the GCF, the
species and its habitat are impacted by the rangewide threats, although
development is less likely in the GCF compared to lands in private
ownership. Human-caused fires have been documented in M. polycladus
habitat even when fire management practices are implemented during the
dry season. The remaining 11 percent of the individuals on Puerto Rico
occur on private lands not managed for conservation, where habitat
destruction and modification resulting from road clearing and wind farm
development and operation may impact individuals and localities. All M.
polycladus individuals on Saba Island and Anegada Island occur on
private lands and are not purposefully managed for conservation.
Occurrences on Saba Island are subject to threats of grazing and human-
induced fire, and potentially to the threat of urbanization and
development. Mitracarpus polycladus on Anegada Island are at risk due
to grazing, urbanization and development, and human-induced fire.
Limited Distribution and Small Population Size
At the time of listing, we identified the species' limited
distribution (i.e., two isolated populations: one in Puerto Rico and
one on Saba Island) coupled with an undetermined but presumably low
number of individuals (i.e., no abundance information was available) as
the primary threats to the species. Since listing, our knowledge
concerning Mitracarpus polycladus's abundance and distribution has
improved, and we are aware of increased individuals and localities
throughout the southern section of the GCF (Service 2018a, p. 22).
Currently, there are three known natural populations (Puerto Rico, Saba
Island, Anegada Island) and one introduced population occurring on
three Caribbean islands across the species' historical range. The
species is restricted to small clusters on exposed limestone, occupying
a total area of 0.44 ha (1.1 ac) in southern Puerto Rico (no areal
extent is estimated for the populations on Anegada and Saba Islands).
The limited distribution of the four populations makes M. polycladus
vulnerable to catastrophic events (e.g.,
[[Page 74899]]
widespread and severe drought and large-scale fires).
Small population size can exacerbate other threats acting on the
species. Populations that are small, isolated by habitat loss or
fragmentation, or impacted by other factors are more vulnerable to
extirpation by natural, randomly occurring events (such as predation or
stochastic weather events), and to genetic effects that plague small
populations, collectively known as small population effects (Purvis et
al. 2000, p. 1947). These effects can include genetic drift, founder
effects (over time, an increasing percentage of the population
inheriting a narrow range of traits), and genetic bottlenecks leading
to increasingly lower genetic diversity, with consequent negative
effects on adaptive capacity and reproductive success (Keller and
Waller 2002, p. 235).
Nine natural localities on Puerto Rico are smaller localities with
varying degrees of connectivity and cross-pollination between
localities; in contrast, only one natural locality, the Mesetas trail
locality in GCF, has a high number of individuals and connectivity. The
best available information for Anegada and Saba Islands indicates that
these populations are currently small (2,500 on Anegada Island and
unknown abundance on Saba Island) and in a few localities with limited
distribution.
Effects of Climate Change and Sea Level Rise
The Intergovernmental Panel on Climate Change (IPCC) concluded that
evidence of warming of the climate system is unequivocal (IPCC 2014,
pp. 2, 40). Observed effects associated with climate change include
widespread changes in precipitation amounts, increased extreme weather
events including droughts, heavy precipitation, heat waves, more
intense tropical cyclones, and an increase in sea level (IPCC 2014, pp.
40-44). Rather than assessing climate change as a single threat in and
of itself, we examined the potential consequences to the species and
its habitat that arise from changes in environmental conditions
associated with various aspects of climate change (temperature,
precipitation, and sea level rise). Vulnerability to climate change
impacts can be defined as a function of sensitivity, exposure, and
adaptive capacity of the species to those changes (IPCC 2007, pp. 6,
21; Glick and Stein 2010, p. 19).
The IPCC-modelled scenarios for the Caribbean islands predict
precipitation declines, sea level rise, stronger and more frequent
extreme weather events, and temperature increases by 2050 (Penn 2010,
p. 45; Khalyani et al. 2016, p. 265; Gould et al. 2018, p. 813; Strauss
and Kulp 2018, p. 3; U.S. Global Change Research Program (USGCRP) 2018,
p. 136). We examined a downscaled model for Puerto Rico and the British
Virgin Islands based on global emissions scenarios from the Climate
Model Intercomparison Project (CMIP3) dataset. The more current CMIP5
dataset was not available for the species' range at the time of
analysis. The Special Report on Emissions (SRES) scenarios using the
CMIP3 dataset are generally comparable to the more recent
representative concentration pathway (RCP) scenarios from RCP4.5 (SRES
B1) to RCP8.5 (SRES A2) (Lorde 2011, entire; IPCC 2014, p. 57; Khalyani
et al. 2016, pp. 267, 279-280). Under both scenarios, emissions
increase, precipitation declines, and temperature and total dry days
increase, resulting in extreme drought conditions that convert
subtropical dry forest into dry and very dry forest (Khalyani et al.
2016, p. 280).
Modeling shows dramatic changes to Puerto Rico through 2100;
however, the divergence in these projections increases after mid-
century (Khalyani et al. 2016, p. 275). By 2050, Puerto Rico is
predicted to be subject to a decrease in rainfall, along with increased
drought intensity (Khalyani et al. 2016 p. 265; USGCRP 2018, p. 136).
As precipitation decreases, influenced by warming, it will tend to
accelerate the hydrological cycles, resulting in wet and dry extremes
(Cashman et al. 2010, pp. 1, 51, 53; Jennings et al. 2014, pp. 1, 5-6).
A reduction in precipitation in the subtropical dry forests, where rain
events are already limited, will affect Mitracarpus polycladus
viability through reduced seed viability and result in increased
seedling mortality. Droughts compromise seedling recruitment as
evidenced following dry periods, when seedling and adult mortality is
the highest and other individuals show partial die-off (Service 2018b,
p. 8). In fact, under experimental conditions, the germination and
survival of seedlings of the closely related M. maxwelliae were
negatively affected by reduced soil moisture (Buitrago-Soto 2002, p.
25). There are indications that the southern region of Puerto Rico,
where M. polycladus occurs, has experienced negative trends in annual
rainfall. Between 2000 and 2016, Puerto Rico had seven drought episodes
concentrated around the south, east, and southeastern regions of the
island. The most severe drought occurred between 2014 and 2016, when
Puerto Rico experienced 80 consecutive weeks of moderate drought, 48
weeks of severe drought, and 33 weeks of extreme drought conditions
(Alvarez-Berr[iacute]os et al. 2018, p. 1). Prolonged dry seasons may
represent a bottleneck for seedlings and promote changes in the
composition of recruits of plant species (Allen et al. 2017, p. 6).
Additionally, prolonged droughts and associated changes in soil
conditions (i.e., temperature and soil humidity) would result in
conditions promoting fire throughout M. polycladus's range, impacting
individuals and reducing seed viability, and therefore species'
recruitment. Moreover, the absence of forest canopy on the exposed
limestone substrate where M. polycladus occurs reduces suitable habitat
conditions (i.e., hydrology and moisture retention) that buffer the
severity of stress resulting from environmental perturbations, such as
droughts.
The IPCC global models and scenarios analyzed for the downscaled
models apply to the Caribbean islands. Downscaled general circulation
models predict dramatic shifts in the life zones of Puerto Rico with
potential loss of subtropical rain, moist, and wet forest, and with the
appearance of tropical dry and very dry forests anticipated (Khalyani
et al. 2016, p. 275). Some species may move to higher elevations in
response to this shift in life zones; however, the extent of a species'
ability to redistribute will depend on its dispersal capability and
forest connectivity (Khalyani et al. 2019, p. 11). Due to Mitracarpus
polycladus's low dispersal capability, clumped spatial distribution,
and habitat requirements (exposed limestone), as well as the limited
availability of its required habitat, a shift from dry to very dry
forest is expected to affect species' viability because of a lack of
suitable habitat and the species' inability to move to suitable
habitat. Based on the similarity of habitat and geographic proximity,
the effects of climate change on Anegada and Saba Islands are expected
to be similar to Puerto Rico as emissions increase, precipitation
declines, and temperature and total dry days increase, resulting in
extreme drought conditions that convert subtropical dry forest into dry
and very dry forest (Khalyani et al. 2016, entire). In the subtropical
dry forest habitat where M. polycladus occurs, climate change may
impact the species through declines in natural recruitment and
population expansion.
Sea level rise is another expected effect of climate change that
may affect coastal communities and habitat in the Caribbean islands
(Penn 2010, entire; Lorde 2011, entire; Strauss and Kulp 2018, p. 1).
Integrated sea level rise projection and flood risk analysis
[[Page 74900]]
predict that floods reaching 0.5 meter (m) (1.64 feet (ft)) above
current high tide levels will become common events throughout most of
the Caribbean by 2050 (Strauss and Kulp 2018, p. 2). Other scenarios
using RCP4.5 and RCP8.5 forecast that by mid-century, sea level is
expected to increase by 0.24 m (0.8 ft) to 0.85 m (2.8 ft) (Church et
al. 2013, p. 1182; Sweet et al. 2017, p. 75; Strauss and Kulp 2018, p.
14). Based on these sea level rise projections, coastal floods will
negatively affect Mitracarpus polycladus habitat at or below the 1.0 m
(3.3 ft) sea level near the coast or in areas with high coastal erosion
through the effects of saltwater inundation. In Puerto Rico, M.
polycladus occurs at elevations ranging from 1.5 m (5 ft) to 52 m (172
ft) from current sea level (Service 2018b, p. 5). On Saba Island, M.
polycladus occurs at an elevation ranging from 12 m (40 ft) to 335 m
(1,100 ft) (Rojer 1997, p. 19; Freitas et al. 2016, p. 10). On Anegada
Island, M. polycladus occurs at elevations ranging from 1 m (3.2 ft) to
8 m (26 ft) from current sea level (B[aacute]rrios 2021, pers. comm.;
Hamilton 2021, pers. comm.). Across the range, the only known locality
in an area with potential to be affected by flooding and sea level rise
is the Windlass site on Anegada Island (approximately 200 M. polycladus
individuals). The Windlass site is located in the sandy and rocky areas
on the northern coast of the island where the habitat is subjected to
high energy wave and coastal erosion (B[aacute]rrios and Hamilton 2018,
p. 5). Mitracarpus polycladus individuals occur in elevations higher
than those we expect to be impacted by sea level rise on Puerto Rico,
Saba Island, and other localities on Anegada Island. Based on predicted
sea level rise and the elevation where most individuals occur, we
determined sea level rise does not pose a threat to the species in the
foreseeable future. Nevertheless, sea level rise may indirectly impact
the species, particularly on Anegada Island, through development
associated with displacement of the human population from coastal areas
to inland and urban areas where individuals of M. polycladus occur
(Penn 2010, pp. 21, 249; Hamilton 2016, p. 101). We do not expect
significant effects to M. polycladus from sea level rise, although one
coastal locality on Anegada Island has the potential to be affected.
In summary, other natural and human-caused factors, such as the
limited distribution of the three known natural populations and the
effects of climate change (i.e., decreased rainfall, severe droughts,
and shift in life zones), are current threats to Mitracarpus
polycladus. The threats to the species will be exacerbated by the
expected changes in climatic conditions by 2050. We expect the
projected changes in habitat and microhabitat conditions of temperature
and rainfall will have negative effects on M. polycladus. The ecology
of M. polycladus appears closely linked to specific current climatic
conditions of rain seasonality and drought periods. By 2050, sea level
rise is expected to affect the Caribbean islands, including Puerto
Rico, Anegada Island, and Saba Island. Overall, the effects of a
changing climate on M. polycladus will be exacerbated by the relatively
low number of populations and habitat degradation and fragmentation,
which can affect the future viability of the species.
Conservation Efforts and Regulatory Mechanisms
In the final listing rule (59 FR 46715; September 9, 1994), we
identified the inadequacy of existing regulatory mechanisms as one of
the factors affecting the continued existence of Mitracarpus
polycladus. Outside of the protections provided by the Act, the
Commonwealth of Puerto Rico legally protects M. polycladus as an
endangered species, including protections to its habitat, through
Commonwealth Law No. 241-1999 (title 12 of the Laws of Puerto Rico at
sections 107-107u) and Regulation 6766 (To govern the management of
threatened and endangered species in the Commonwealth of Puerto Rico),
which prohibit collecting, cutting, and removal, among other actions,
of listed plants (DRNA 2004, p. 11). These protections are described
further in our June 23, 2022, proposed rule (87 FR 37476). Although
there are legal mechanisms in place (e.g., laws or regulations) for the
protection of M. polycladus, the enforcement of such mechanisms on
private and public land is sometimes challenging. Land managers,
landowners, and law enforcement officers are not always aware of the
localities occupied by the species throughout its range or may have
difficulty correctly identifying the plant (Service 2018b, p. 10).
Therefore, limited public awareness of the species and its status
exacerbates the challenge of implementation of existing laws and
regulations and affects conservation of M. polycladus and its habitat.
On Anegada Island, various conservation and education efforts are
taking place for the protection of rare plant and animal species
(Gardner et al. 2008, entire; IRF 2013, p. 29). However, we are unaware
of any formal regulatory mechanism that protects Mitracarpus polycladus
on Anegada Island or Saba Island (Geelhoed et al. 2013, p. 12).
We do not expect this species to be removed from legal protection
by the Commonwealth when it is reclassified as a threatened species
under the Act. This plant is now more abundant, is widely distributed,
and largely occurs within conserved lands. Despite the existing
regulatory mechanisms and conservation efforts, the threats discussed
above are still affecting the species to the extent that it does not
meet the criteria for delisting. However, additional opportunities
exist to engage the public and provide information about M. polycladus
and support the enforcement of existing protective mechanisms.
Overall Summary of Factors Affecting the Species
We have carefully assessed the best scientific and commercial
information available regarding the threats that are currently
impacting and expected to impact Mitracarpus polycladus in developing
this rule. Limited distribution and a low number of individuals were
considered a threat to M. polycladus when we listed the species (59 FR
46715; September 9, 1994). Recent information indicates the species is
more abundant and widely distributed than was known at the time of
listing, and most individuals occur in protected lands where threats
are reduced, although threats are still present. We determined that
habitat destruction and modification (e.g., vegetation clearance with
trail and road maintenance activities, human-caused fires, encroachment
by nonnative and invasive species, urbanization and tourism
development, and grazing), as well as other natural or manmade factors
such as limited distribution and the effects of climate change, will
continue to pose threats to M. polycladus in the foreseeable future.
We evaluated the biological status of this species, both currently
and into the future, considering the species' viability as
characterized by its resiliency, redundancy, and representation.
Mitracarpus polycladus has demonstrated some level of resiliency to
natural and anthropogenic disturbances in the past. Adult individuals
have overcome disturbances such as droughts and habitat modification,
road and trail maintenance, and fires. However, seedlings are
susceptible to the effects of drought and to the invasion of nonnative
plant species after fire or other disturbance events. The lack of or
reduced seedling recruitment affects
[[Page 74901]]
population demographics and the long-term viability of the species.
For Mitracarpus polycladus to maintain viability, populations, or
some portion thereof, must be sufficiently resilient. Resiliency
describes the ability of a population to withstand stochastic events
(arising random factors). We can measure resiliency based on metrics of
population health: for example, birth versus death rates and population
size. For this rule, our classification of resiliency relies heavily on
the biology of the species and habitat characteristics in the absence
of highly certain population size or trend estimates.
We broadly defined categories of resiliency for Mitracarpus
polycladus populations by assessing demographic and habitat parameters
and anchored these categories in the species' needs and life-history
characteristics (see table 3, below). Important species'
characteristics center on the species' seasonality, seedling mortality
after drought, dispersal capability, and competition with nonnative
grasses for space and resources. The demographic metrics we evaluated
include abundance at localities and evidence of reproduction or
recruitment. We assessed habitat characteristics, including the degree
of habitat protection (or, conversely, development risk), extent of
suitable habitat, connectivity to other localities, and vulnerability
to threats. A population may not exhibit each characteristic of the
category as defined, but most parameters known for the population fall
into the resilience category. For example, a population that is
described as highly resilient may have high abundance, high number of
localities, good distribution of localities, and recruitment at most
localities even if suitable habitat and connectivity is limited.
Table 3--Definitions for Mitracarpus polycladus Population Resiliency
Categories
------------------------------------------------------------------------
High Moderate Low
------------------------------------------------------------------------
Abundance is high;. Abundance Abundance
is moderate;. is low.
Number of Number of Number of
localities is high, and localities is localities is
they occupy a greater moderate, and they limited to one, and
spatial extent within occupy a limited it occupies a very
suitable habitat; spatial extent restricted spatial
within suitable extent.
habitat;
Reproduction and No
recruitment are such that Reproduction and/or reproduction or
the population remains recruitment is recruitment is
stable or increases; occurring at some occurring.
Abundant suitable localities; Mortality
habitat occurs outside Recruitment exceeds recruitment
known localities; and. and mortality are such that the
Connectivity occurs equal such that the population is
among most localities.. population does not declining.
grow, or the Limited or
population trend is no suitable habitat
unknown;. occurs outside
Some known locality; and
suitable habitat There is no
occurs outside connectivity
known localities; between localities
and. (single locality
population).
Connectivity occurs
between at least
two localities.
------------------------------------------------------------------------
Currently, three Mitracarpus polycladus natural populations are
known from three islands in the Caribbean (i.e., Puerto Rico, Anegada
Island, and Saba Island). In Puerto Rico, many M. polycladus adult
individuals occur in small clusters, and seedlings have been
documented, particularly after rain events. Information from Anegada
Island and Saba Island is very limited, making it difficult to
determine the level of population resiliency. However, both of those
populations of M. polycladus demonstrate some level of resiliency as
populations remain on the landscape on both islands and have presumably
overcome historical disturbances of varying magnitude and duration,
including habitat modification.
The short time it takes Mitracarpus polycladus to reach
reproductive size and the extent of seed production facilitates
population-level resiliency. However, resiliency is limited by the
small size of clusters of individuals, species' seasonality, low
dispersal capacity, and high seedling mortality. We have no evidence
that known M. polycladus clusters are expanding or colonizing suitable
habitat away from roads and trails. The lack of expansion and
colonization results in isolated clusters with an increased chance of
reduced genetic variation due to genetic drift, potentially resulting
in inbreeding depression and lower resiliency. In addition, M.
polycladus has been displaced by nonnative, invasive species after
habitat disturbance by fire, which further precludes the effective
recruitment of the species. The M. polycladus population in Puerto Rico
occurs on 0.44 ha (1.1 ac) of habitat in 10 naturally occurring and 1
introduced locality. Suitable habitat connects some, but not all,
localities. Increased connectivity between scattered localities in
Puerto Rico is expected to improve population resiliency. The Saba and
Anegada Islands populations occur in limited areas as well. We do not
have information about the population trend and areal extent of these
localities. Overall, the limited areal extent of M. polycladus
contributes to its susceptibility to stochastic and catastrophic
events. Based on these factors, we determined that the Puerto Rico
population currently exhibits moderate resiliency while the Anegada and
Saba Islands populations exhibit unknown or low resiliency.
The species' viability is also affected by its ability to adapt to
changing environmental conditions. We have no information on the
genetic variability of Mitracarpus polycladus nor information on
variation in adaptive life-history traits, and, therefore, we evaluated
the species' ability to adapt based on its likelihood of maintaining
the breadth of genetic diversity and gene flow. This species occurs in
small patches of suitable habitat within subtropical dry forest on
three islands of the Caribbean with little variation in habitat
conditions between populations. Historically, genetic diversity may
have contributed to the species' ability to adapt to changing
conditions, and the species likely has maintained underlying genetic
diversity. Rangewide, all populations are vulnerable to the threats
that could result in the extirpation of clusters of individuals or
localities and the loss of genetic representation.
The ability of the species to adapt is also a function of the level
of gene flow among populations. The three Mitracarpus polycladus
populations are disconnected; thus, gene flow is limited to individuals
within populations due to the lack of connectivity that would allow
cross-pollination among populations. As described above in Limited
Distribution and Small Population Size, small, isolated populations are
susceptible to genetic effects; however, the best available information
indicates that species
[[Page 74902]]
viability is not affected by genetic issues at present. As
fragmentation increases, gene flow will be reduced further, and the
populations will become more vulnerable to genetic drift and
inbreeding, thereby reducing the species' adaptive capacity. We
determined M. polycladus representation is likely reduced from
historical representation due to reduced or fragmented habitat
conditions, but the species maintains moderate adaptive capacity.
Lastly, the species' viability depends on its ability to withstand
catastrophic events, which is a function of the resiliency, number, and
distribution of Mitracarpus polycladus populations. The more
sufficiently resilient populations, and the wider the distribution of
those populations, the more redundancy the species will exhibit. The
primary catastrophic risks to M. polycladus include widespread,
prolonged drought and fire. These threats are expected to increase in
the future as the subtropical dry forest where the species occurs
shifts to very dry forest habitat. The species' largest population
(Puerto Rico) is moderately resilient and now occurs in a wider
rangewide distribution than was known historically. We have determined
M. polycladus currently exhibits moderate species redundancy.
In summary, the current abundance of Mitracarpus polycladus has
increased and some of the identified threats have decreased since its
listing in 1994. However, our analysis indicates that threats and
stressors continue to affect the species. We based our analyses on
biological factors, expert judgment regarding the consequences of
interacting stressors to the species' viability, and our assessment of
likely future habitat conditions.
Determination of Mitracarpus polycladus's Status
Section 4 of the Act (16 U.S.C. 1533) and its implementing
regulations (50 CFR part 424) set forth the procedures for determining
whether a species meets the definition of an endangered species or
threatened species. The Act defines an ``endangered species'' as a
species that is in danger of extinction throughout all or a significant
portion of its range and a ``threatened species'' as a species that is
likely to become an endangered species within the foreseeable future
throughout all or a significant portion of its range. The Act requires
that we determine whether a species meets the definition of endangered
species or threatened species based on one or more of the following
factors: (A) The present or threatened destruction, modification, or
curtailment of its habitat or range; (B) overutilization for
commercial, recreational, scientific, or educational purposes; (C)
disease or predation; (D) the inadequacy of existing regulatory
mechanisms; or (E) other natural or manmade factors affecting its
continued existence.
Status Throughout All of Its Range
After evaluating threats to the species and assessing the
cumulative effect of the threats under the Act's section 4(a)(1)
factors, we have determined that Mitracarpus polycladus's current
viability is higher than was known at the time of listing (current
abundance estimate of more than 20,000 adult individuals in three
populations) and most individuals occur on protected lands where
threats are reduced. At the time of listing, the known range of M.
polycladus consisted of an undetermined number of individuals located
in a single population in southern Puerto Rico and from one record on
Saba Island. The primary threats were habitat destruction and
modification, inadequacy of existing regulatory mechanisms, and limited
distribution (see 59 FR 46715, September 9, 1994, pp. 46716-46717).
Currently, M. polycladus is known to occur in 11 localities within an
areal extent of 0.44 ha (1.1 ac) in southern Puerto Rico and several
localities on Saba Island and Anegada Island. In Puerto Rico, about 89
percent of the known M. polycladus individuals occur within the GCF, a
forest managed for conservation by the Department in a manner
compatible with M. polycladus's needs and protected by Commonwealth
regulations.
The remaining 11 percent of individuals on Puerto Rico and
individuals on Saba and Anegada Islands occur on private lands and are
at risk due to habitat destruction and modification from wind farm
projects, urbanization, and tourism development. Information from
Puerto Rico also indicates that threats from human-caused fires, human
trampling, and nonnative and invasive species impact Mitracarpus
polycladus on both public and private lands. These threats may be more
severe for the populations on private lands, since fire management
prevention practices and other management actions implemented on public
lands are not required on private lands. On Saba and Anegada Islands,
the species also faces threats due to residential and commercial
development and degradation due to grazing of feral livestock.
Information from Anegada Island and Saba Island is very limited, making
it difficult to determine the level of population resiliency; however,
both populations demonstrate some level of resiliency as we have
longstanding records from the same localities that have presumably
overcome historical disturbances of varying magnitude and duration,
including habitat modification. Thus, we determined the Puerto Rico
population currently exhibits moderate resiliency and the resiliency of
the Anegada and Saba Islands populations is unknown or low.
The species' distribution is wider than known at the time of
listing, and the species' listing by the Commonwealth of Puerto Rico
provides some level of protection to Mitracarpus polycladus. However,
remaining threats are ongoing and projected to impact the species in
the future. These include the present or threatened destruction,
modification, or curtailment of its habitat or range (e.g., maintenance
of existing roads and trails, human trampling, human-caused fires,
encroachment of nonnative and invasive species after fires and other
habitat modification activities, and urbanization and tourism
development) (Factor A); and other natural or manmade factors affecting
the continued existence of M. polycladus throughout its range (e.g.,
limited distribution and the effects of climate change) (Factor E). The
best available information does not indicate that overutilization or
diseases are affecting the species or feral livestock are specifically
targeting this species and consuming it. Despite the identification of
these threats that currently, and are expected to continue to, impact
the species, we conclude that the populations exhibit sufficient
resiliency and species-level representation and redundancy.
In summary, Mitracarpus polycladus is distributed across a narrow
range, but the number of localities within populations and
environmental conditions have improved since the time of listing. Thus,
after assessing the best available information, we conclude that M.
polycladus is not in danger of extinction now throughout all of its
range. We therefore proceed with determining whether M. polycladus is
likely to become endangered within the foreseeable future throughout
all of its range.
Based on biological factors and stressors to the species'
viability, we determined 25 years to be the foreseeable future within
which we can reasonably project threats and the species' response to
those threats. The foreseeable future for the individual
[[Page 74903]]
factors and threats varies. We reviewed available information including
forest management plans, proposed development projects, and fire
history within the range of the species, to inform our assessment of
likely future levels for each threat. Projections for 2050 predict
increases in temperature and decreases in precipitation (Khalyani et
al. 2016, pp. 274-275). However, divergence in temperature and
precipitation projections increase dramatically after mid-century among
climate change scenarios, making late-century projections more
uncertain and reducing our ability to reliably predict stressors
associated with climate change (Khalyani et al. 2016, p. 275). In
addition, observation of threats and the effects of those threats on
the species since it was listed in 1994 (more than 25 years ago) have
given us a baseline to understand how threats may impact the species.
We have observed the effects of habitat destruction and modification
(such as vegetation clearance for maintaining or improving trails and
access roads, human trampling, human-caused fires, invasive species,
and urban and tourist development) and climate change (predicted
changes in temperature, increased droughts, and life zones shifting) on
the species since its listing and incorporated these observations to
reliably predict the species' response to these threats.
The 25-year period includes multiple generations of the species and
allowed adequate time for impacts from conservation efforts or changes
in threats to be observed through population responses. This timeframe
accounts for the species' reproductive biology, and thus the time
required by multiple generations of Mitracarpus polycladus to reach a
reproductive size and effectively contribute to the viability of the
species. It accounts for reaching maturity, flowering, setting viable
fruits and seeds, seed germination, and seedling survival and
establishment, and it allows environmental stochastic events such as
severe drought periods to affect the species. Furthermore, the
established timeframe provides an opportunity to analyze the
implications of the Department's forest management actions, and
existing laws and regulations to protect currently known populations.
Although population numbers and abundance of Mitracarpus polycladus
have increased and the species' occurrences appear stable, threats
remain in magnitude, scope, and impact over time. Habitat destruction
and modification, such as vegetation clearance for maintaining or
improving trails and access roads, human trampling, human-caused fires,
invasive species, and urban and tourist development (Factor A), and
other natural or manmade factors such as the effects of climate change
(Factor E) may limit the species' abundance and distribution of
occurrences. Gene flow will continue to be limited to individuals
within populations due to the lack of connectivity that would allow
cross-pollination among populations; populations may become more
vulnerable to genetic drift and inbreeding, thereby reducing the
species' ability to adapt to changing conditions. Although much of the
Puerto Rico population occurs in the GCF, which is managed for
conservation, actions that benefit the species will not eliminate the
threats of trail maintenance, trampling, nonnative and invasive
species, and human-caused fires, and these threats are expected to
continue to affect the species in the foreseeable future. Proposed
urbanization and tourism development projects may be completed in the
foreseeable future. Furthermore, under climate change projections, the
risk of catastrophic drought and fire is expected to increase with the
subtropical dry forest shifting to very dry forest habitat within the
foreseeable future.
The magnitude of effects associated with habitat destruction and
modification along with climate change are expected to continue and
potentially increase in the foreseeable future. Despite the existing
regulatory mechanisms and conservation efforts, the threats discussed
above are still affecting the species to the extent that it does not
meet the criteria for delisting. Thus, after assessing the best
available information, we conclude that M. polycladus is not currently
in danger of extinction, but is likely to become in danger of
extinction within the foreseeable future throughout all of its range.
Status Throughout a Significant Portion of Its Range
Under the Act and our implementing regulations, a species may
warrant listing if it is in danger of extinction or likely to become so
in the foreseeable future throughout all or a significant portion of
its range. The court in Center for Biological Diversity v. Everson, 435
F. Supp. 3d 69 (D.D.C. 2020) (Everson), vacated the provision of the
Final Policy on Interpretation of the Phrase ``Significant Portion of
Its Range'' in the Endangered Species Act's Definitions of ``Endangered
Species'' and ``Threatened Species'' (hereafter ``Final Policy''; 79 FR
37578; July 1, 2014) that provided that if the Service determines that
a species is threatened throughout all of its range, the Service will
not analyze whether a species is endangered in a significant portion of
its range.
Therefore, we proceed to evaluating whether the species is
endangered in a significant portion of its range--that is, whether
there is any portion of the species' range for which both (1) the
portion is significant, and (2) the species is in danger of extinction
in that portion. Depending on the case, it might be more efficient for
us to address the ``significance'' question or the ``status'' question
first. We can choose to address either first. Regardless of which
question we address first, if we reach a negative answer with respect
to the first question that we address, we do not need to evaluate the
other question for that portion of the species' range.
Following the court's holding in Everson, we now consider whether
there are any significant portions of the species' range where the
species is in danger of extinction now (i.e., endangered). In
undertaking this analysis for Mitracarpus polycladus, we choose to
address the status question first by considering information pertaining
to the geographic distribution of both the species and the threats that
the species faces to determine whether there are any portions of the
range where the species is endangered.
We evaluated the range of Mitracarpus polycladus to determine if
the species is in danger of extinction now in any portion of its range.
The range of a species can theoretically be divided into portions in an
infinite number of ways. We focused our analysis on portions of the
species' range that may meet the Act's definition of an endangered
species. For M. polycladus, we considered whether the threats or their
effects on the species are greater in any biologically meaningful
portion of the species' range than in other portions such that the
species is now in danger of extinction in that portion.
We examined the following threats: habitat loss and modification
due to vegetation maintenance or trimming along roads and trails, human
trampling, and urbanization and tourism development; human-caused
fires; nonnative, invasive plant species; and the effects of climate
change (prolonged droughts, expected shifts of life zones, and sea
level rise), including cumulative effects. We also considered whether
these threats may be exacerbated by small population size and limited
connectivity between
[[Page 74904]]
populations. For detailed description of each threat, see Summary of
Biological Status and Threats, above.
Habitat modification poses a threat to most of the 11 Mitracarpus
polycladus localities in Puerto Rico, as well as the populations on
Saba and Anegada Islands. The M. polycladus populations on Puerto Rico,
Anegada Island, and Saba Island experience threats of habitat
degradation and modification due to vegetation clearance for
maintenance and improvement of roads and trails, urbanization and
tourism development, human-caused fires, and the subsequent
encroachment of nonnative and invasive species. In addition,
approximately 11 percent of M. polycladus individuals in Puerto Rico
occur on private lands that are exposed to the threat of development
more so than individuals on protected lands. Moreover, the species'
localities in each population are distributed across a limited
geographic area. Although climate change is expected to affect M.
polycladus populations in the foreseeable future, we determined that
climate change does not represent a current threat to the species;
therefore, our assessment of the threat of climate change as a future
threat is consistent with our ``threatened'' status determination for
the species.
Small population size can exacerbate other threats on the species.
The information regarding Mitracarpus polycladus populations on Anegada
and Saba Islands is more limited than that regarding the Puerto Rico
population. Based on the best available information for Anegada and
Saba Islands, these populations are currently small or assumed to be
small (2,500 on Anegada Island and unknown abundance on Saba Island)
and in a few localities with limited distribution. Ten of the 11
species' localities on Puerto Rico also occur in clusters with low
numbers of individuals that are isolated from other clusters, but the
species is represented by a wider distribution on Puerto Rico than on
Anegada and Saba Islands. Despite the rarity of M. polycladus on
Anegada and Saba Islands, the species has demonstrated continued
presence for decades in some localities. Although species' persistence
does not equate with high resiliency or viability of a population or
species, we expect M. polycladus populations to maintain resiliency in
the future, despite ongoing threats. Therefore, small population size
and low abundance in these localities, even when considered in the
context of other threats, do not represent a concentration of threats
at a biologically meaningful scale such that the species may be in
danger of extinction in this portion. Based on our review of
information and the synergistic effects of threats on Anegada and Saba
Islands, this portion of the species' range does not provide a basis
for determining that the species is in danger of extinction in a
significant portion of its range.
Overall, we found that threats likely are impacting individuals or
populations similarly across the species' range. Kinds of threats and
levels of threats are more likely to vary across a species' range if
the species has a large range rather than a very small natural range,
such as M. polycladus. Species with limited ranges are more likely to
experience the same types and generally the same levels of threats in
all parts of their range. These threats are certain to occur, and
populations are facing the same extent of threats, even though certain
populations may have fewer occurrences.
We found no portion of Mitracarpus polycladus's range where threats
are impacting individuals differently than elsewhere in its range to
the extent that the status of the species in one portion differs from
any other portion of its range.
Therefore, no portion of the species' range provides a basis for
determining that the species is in danger of extinction in a
significant portion of its range, and we determine that the species is
likely to become in danger of extinction within the foreseeable future
throughout all of its range. This does not conflict with the courts'
holdings in Desert Survivors v. U.S. Department of the Interior, 321 F.
Supp. 3d 1011, 1070-74 (N.D. Cal. 2018) and Center for Biological
Diversity v. Jewell, 248 F. Supp. 3d 946, 959 (D. Ariz. 2017) because,
in reaching this conclusion, we did not need apply the aspects of the
Final Policy, including the definition of ``significant,'' that those
court decisions held were invalid.
Determination of Status
Our review of the best available scientific and commercial
information indicates that Mitracarpus polycladus meets the Act's
definition of a threatened species. Therefore, we are reclassifying M.
polycladus as a threatened species in accordance with sections 3(20)
and 4(a)(1) of the Act.
II. Final Rule Issued Under Section 4(d) of the Act
Under section 4(d) of the Act, the Secretary may promulgate
protective regulations for threatened species. Because we are
reclassifying this species as a threatened species, the prohibitions in
section 9 will not apply directly. We are, therefore, promulgating
below a set of regulations to provide for the conservation of the
species in accordance with the Act's section 4(d), which also
authorizes us to apply any of the prohibitions in section 9 to a
threatened species. The discussion below regarding protective
regulations under section 4(d) of the Act complies with our policy, as
published in the Federal Register on July 1, 1995 (59 FR 34272), to
identify to the maximum extent practical at the time a species is
listed, those activities that would or would not constitute a violation
of section 9 of the Act.
Background
Section 4(d) of the Act contains two sentences. The first sentence
states that the Secretary shall issue such regulations as she deems
necessary and advisable to provide for the conservation of species
listed as ``threatened.'' The U.S. Supreme Court has noted that
statutory language similar to the language in section 4(d) of the Act
authorizing the Secretary to take action that she ``deems necessary and
advisable'' affords a large degree of deference to the agency (see
Webster v. Doe, 486 U.S. 592 (1988)). Conservation is defined in the
Act to mean the use of all methods and procedures which are necessary
to bring any endangered species or threatened species to the point at
which the measures provided pursuant to the Act are no longer
necessary. Additionally, the second sentence of section 4(d) of the Act
states that the Secretary may by regulation prohibit with respect to
any threatened species any act prohibited under section 9(a)(1), in the
case of fish or wildlife, or section 9(a)(2), in the case of plants.
Thus, the combination of the two sentences of section 4(d) provides the
Secretary with wide latitude of discretion to select and promulgate
appropriate regulations tailored to the specific conservation needs of
a threatened species. The second sentence grants particularly broad
discretion to us when adopting prohibitions under section 9.
The courts have recognized the extent of the Secretary's discretion
under this standard to develop rules that are appropriate for the
conservation of a species. For example, courts have upheld, as a valid
exercise of agency authority, rules developed under section 4(d) that
included limited prohibition against takings (see Alsea Valley Alliance
v. Lautenbacher, 2007 WL 2344927 (D. Or. 2007); Washington
Environmental Council v. National Marine Fisheries Service, 2002 WL
511479 (W.D. Wash. 2002)). Courts have also upheld 4(d) rules that do
not
[[Page 74905]]
address all of the threats a species faces (see State of Louisiana v.
Verity, 853 F.2d 322 (5th Cir. 1988)). As noted in the legislative
history when the Act was initially enacted, ``once an animal is on the
threatened list, the Secretary has an almost infinite number of options
available to [her] with regard to the permitted activities for those
species. [She] may, for example, permit taking, but not importation of
such species, or [she] may choose to forbid both taking and importation
but allow the transportation of such species'' (H.R. Rep. No. 412, 93rd
Cong., 1st Sess. 1973).
The provisions of this 4(d) rule promote conservation of
Mitracarpus polycladus by encouraging management of the habitat in ways
that facilitate conservation for the species. The provisions of this
rule are one of many tools that we use to promote the conservation of
M. polycladus. As explained below, we are adopting a species-specific
rule that sets out all of the protections and prohibitions applicable
to M. polycladus.
Section 7(a)(2) of the Act requires Federal agencies, including the
Service, to ensure that any action they fund, authorize, or carry out
is not likely to jeopardize the continued existence of any endangered
species or threatened species or result in the destruction or adverse
modification of designated critical habitat of such species.
If a Federal action may affect a listed species or its critical
habitat, the responsible Federal agency (action agency) must enter into
consultation with us. Examples of actions that are subject to the
section 7 consultation process are actions on State, Tribal, local, or
private lands that require a Federal permit (such as a permit from the
U.S. Army Corps of Engineers under section 404 of the Clean Water Act
(33 U.S.C. 1251 et seq.) or a permit from the Service under section 10
of the Act) or that involve some other Federal action (such as funding
from the Federal Highway Administration, Federal Aviation
Administration, or the Federal Emergency Management Agency). Federal
actions not affecting listed species or critical habitat--and actions
on State, Tribal, local, or private lands that are not federally
funded, authorized, or carried out by a Federal agency--do not require
section 7 consultation.
These requirements are the same for a threatened species with a
species-specific 4(d) rule. For example, as with an endangered species,
if a Federal agency determines that an action is ``not likely to
adversely affect'' a threatened species, the action will require formal
consultation and the formulation of a biological opinion (50 CFR
402.14(a)).
Provisions of the 4(d) Rule
Exercising the Secretary's authority under section 4(d) of the Act,
we have developed a species-specific rule that is designed to address
Mitracarpus polycladus's conservation needs. As discussed previously in
Summary of Biological Status and Threats, we have concluded that
Mitracarpus polycladus is likely to become in danger of extinction
within the foreseeable future primarily due to the present or
threatened destruction, modification, or curtailment of its habitat or
range (specifically, road and trail maintenance, human-caused fires,
nonnative and invasive species, urbanization and tourism development;
and grazing); and other natural or manmade factors (specifically, the
effects of climate change). Section 4(d) requires the Secretary to
issue such regulations as she deems necessary and advisable to provide
for the conservation of each threatened species and authorizes the
Secretary to include among those protective regulations any of the
prohibitions that section 9(a)(2) of the Act prescribes for endangered
species. We find that the protections, prohibitions, and exceptions in
this species-specific rule as a whole satisfy the requirement in
section 4(d) of the Act to issue regulations deemed necessary and
advisable to provide for the conservation of M. polycladus.
The protective regulations we are finalizing for Mitracarpus
polycladus incorporate prohibitions from section 9(a)(2) of the Act to
address threats to the species. Section 9(a)(2) prohibits the following
activities for endangered plants: importing or exporting; certain acts
related to removing, damaging, and destroying; delivering, receiving,
carrying, transporting, or shipping in interstate or foreign commerce
in the course of commercial activity; or selling or offering for sale
in interstate or foreign commerce. These protective regulations include
all of these prohibitions for M. polycladus because the species is at
risk of extinction within the foreseeable future and putting these
prohibitions in place will help to protect the species' existing
populations, slow its rate of decline, and decrease synergistic,
negative effects from other threats.
The exceptions to the prohibitions include all of the general
exceptions to the prohibitions for endangered plants against removing
and reducing to possession, as set forth at 50 CFR 17.61(c), and
certain other specific activities that we except, as described below.
Despite these prohibitions regarding threatened species, we may under
certain circumstances issue permits to carry out one or more otherwise-
prohibited activities, including those described above. The regulations
that govern permits for threatened plants state that the Director may
issue a permit authorizing any activity otherwise prohibited with
regard to threatened species (50 CFR 17.72). Those regulations also
state that the permit shall be governed by the provisions of Sec.
17.72 unless a special rule applicable to the plant is provided in
Sec. Sec. 17.73 to 17.78. Therefore, permits for threatened species
are governed by the provisions of Sec. 17.72 unless a species-specific
4(d) rule provides otherwise. However, under our recent revisions to
Sec. 17.71, the prohibitions in Sec. 17.71(a) do not apply to any
plant listed as a threatened species after September 26, 2019. As a
result, for threatened plant species listed after that date, any
protections must be contained in a species-specific 4(d) rule. We did
not intend for those revisions to limit or alter the applicability of
the permitting provisions in Sec. 17.72, or to require that every
species-specific 4(d) rule spell out any permitting provisions that
apply to that species and species-specific 4(d) rule. To the contrary,
we anticipate that permitting provisions will generally be similar or
identical for most species, so applying the provisions of Sec. 17.72
unless a species-specific 4(d) rule provides otherwise will likely
avoid substantial duplication. Under 50 CFR 17.72 with regard to
threatened plants, a permit may be issued for the following purposes:
For scientific purposes, to enhance propagation or survival, for
economic hardship, for botanical or horticultural exhibition, for
educational purposes, or for other activities consistent with the
purposes and policy of the Act. Additional statutory exceptions from
the prohibitions are found in sections 9 and 10 of the Act.
We recognize the beneficial and educational aspects of activities
with seeds of cultivated plants, which generally enhance the
propagation of the species and, therefore, will satisfy permit
requirements under the Act. We intend to monitor the interstate and
foreign commerce and import and export of these specimens in a manner
that will not inhibit such activities, providing the activities do not
represent a threat to the species' survival in the wild. In this
regard, seeds of cultivated specimens will not be subject to the
prohibitions above, provided that a statement that the seeds are of
``cultivated origin'' accompanies the
[[Page 74906]]
seeds or their container (e.g., the seeds could be moved across State
lines or between territories for purposes of seed banking or use for
outplanting without additional regulations) (50 CFR 17.71(a)).
We recognize the special and unique relationship with our State and
Territorial natural resource agency partners in contributing to
conservation of listed species. State and Territorial agencies often
possess scientific data and valuable expertise on the status and
distribution of endangered, threatened, and candidate species of
wildlife and plants. State and Territorial agencies, because of their
authorities and their close working relationships with local
governments and landowners, are in a unique position to assist us in
implementing all aspects of the Act. In this regard, section 6 of the
Act provides that we must cooperate to the maximum extent practicable
with the States and Territories in carrying out programs authorized by
the Act. Therefore, any qualified employee or agent of a State or
Territorial conservation agency that is a party to a cooperative
agreement with the Service in accordance with section 6(c) of the Act,
who is designated by his or her agency for such purposes, will be able
to conduct activities designed to conserve Mitracarpus polycladus that
may result in otherwise prohibited activities without additional
authorization.
Nothing in this 4(d) rule will change in any way the recovery
planning provisions of section 4(f) of the Act, the consultation
requirements under section 7 of the Act, or our ability to enter into
partnerships for the management and protection of Mitracarpus
polycladus. However, interagency cooperation may be further streamlined
through planned programmatic consultations for the species between
Federal agencies and the Service.
Required Determinations
National Environmental Policy Act (42 U.S.C. 4321 et seq.)
Regulations adopted pursuant to section 4(a) of the Act are exempt
from the National Environmental Policy Act (NEPA; 42 U.S.C. 4321 et
seq.) and do not require an environmental analysis under NEPA. We
published a notice outlining our reasons for this determination in the
Federal Register on October 25, 1983 (48 FR 49244). This includes
listing, delisting, and reclassification rules, as well as critical
habitat designations and species-specific protective regulations
promulgated concurrently with a decision to list or reclassify a
species as threatened. The courts have upheld this position (e.g.,
Douglas County v. Babbitt, 48 F.3d 1495 (9th Cir. 1995) (critical
habitat); Center for Biological Diversity v. U.S. Fish and Wildlife
Service, 2005 WL 2000928 (N.D. Cal. Aug. 19, 2005) (concurrent 4(d)
rule)).
Government-to-Government Relationship With Tribes
In accordance with the President's memorandum of April 29, 1994
(Government-to-Government Relations with Native American Tribal
Governments; 59 FR 22951), Executive Order 13175 (Consultation and
Coordination with Indian Tribal Governments), and the Department of the
Interior's manual at 512 DM 2, we readily acknowledge our
responsibility to communicate meaningfully with federally recognized
Tribes on a government-to-government basis. In accordance with
Secretary's Order 3206 of June 5, 1997 (American Indian Tribal Rights,
Federal-Tribal Trust Responsibilities, and the Endangered Species Act),
we readily acknowledge our responsibilities to work directly with
Tribes in developing programs for healthy ecosystems, to acknowledge
that Tribal lands are not subject to the same controls as Federal
public lands, to remain sensitive to Indian culture, and to make
information available to Tribes. There are no federally recognized
Tribes in the range of Mitracarpus polycladus.
References Cited
A complete list of references cited in this rulemaking is available
on the internet at https://www.regulations.gov and upon request from
the Caribbean Ecological Services Field Office (see FOR FURTHER
INFORMATION CONTACT).
Authors
The primary authors of this final rule are the staff members of the
Caribbean Ecological Services Field Office.
List of Subjects in 50 CFR Part 17
Endangered and threatened species, Exports, Imports, Plants,
Reporting and recordkeeping requirements, Transportation, Wildlife.
Regulation Promulgation
Accordingly, we hereby amend part 17, subchapter B of chapter I,
title 50 of the Code of Federal Regulations, as set forth below:
PART 17--ENDANGERED AND THREATENED WILDLIFE AND PLANTS
0
1. The authority citation for part 17 continues to read as follows:
Authority: 16 U.S.C. 1361-1407; 1531-1544; and 4201-4245,
unless otherwise noted.
0
2. In Sec. 17.12, in paragraph (h), amend the List of Endangered and
Threatened Plants by revising the entry for ``Mitracarpus polycladus''
under FLOWERING PLANTS to read as follows:
Sec. 17.12 Endangered and threatened plants.
* * * * *
(h) * * *
----------------------------------------------------------------------------------------------------------------
Listing citations and
Scientific name Common name Where listed Status applicable rules
----------------------------------------------------------------------------------------------------------------
Flowering Plants
* * * * * * *
Mitracarpus polycladus.......... No common name..... Wherever found.... T 59 FR 46715, 9/9/1994;
88 FR [Insert Federal
Register page where
the document begins],
11/1/2023; 50 CFR
17.73(i).\4d\
* * * * * * *
----------------------------------------------------------------------------------------------------------------
0
3. Amend Sec. 17.73 by adding paragraph (i) to read as follows:
Sec. 17.73 Special rules--flowering plants.
* * * * *
(i) Mitracarpus polycladus (no common name).
(1) Prohibitions. The following prohibitions that apply to
endangered plants also apply to Mitracarpus polycladus. Except as
provided under paragraph (i)(2) of this section, it is unlawful for any
person subject to the jurisdiction of the United States to commit, to
attempt to commit, to solicit
[[Page 74907]]
another to commit, or cause to be committed, any of the following acts
in regard to this species:
(i) Import or export, as set forth at Sec. 17.61(b) for endangered
plants.
(ii) Remove and reduce to possession the species from areas under
Federal jurisdiction; maliciously damage or destroy the species on any
such area; or remove, cut, dig up, or damage or destroy the species on
any other area in knowing violation of any law or regulation of the
Territory or in the course of any violation of a Territorial criminal
trespass law.
(iii) Interstate or foreign commerce in the course of commercial
activity, as set forth at Sec. 17.61(d) for endangered plants.
(iv) Sale or offer for sale, as set forth at Sec. 17.61(e) for
endangered plants.
(2) Exceptions from prohibitions. In regard to this species, you
may:
(i) Conduct activities as authorized by permit under Sec. 17.72.
(ii) Remove, cut, dig up, damage, or destroy on areas not under
Federal jurisdiction if you are a qualified employee or agent of the
Service or Territorial conservation agency which is a party to a
cooperative agreement with the Service in accordance with section 6(c)
of the Act, and you have been designated by that agency for such
purposes, when acting in the course of official duties.
(iii)(A) Any employee or agent of the Service, any other Federal
land management agency, or a Territorial conservation agency, who is
designated by that agency for such purposes, may, when acting in the
course of official duties, remove and reduce to possession Mitracarpus
polycladus from areas under Federal jurisdiction without a permit if
such action is necessary to:
(1) Care for a damaged or diseased specimen;
(2) Dispose of a dead specimen; or
(3) Salvage a dead specimen which may be useful for scientific
study.
(B) Any removal and reduction to possession pursuant to this
paragraph must be reported in writing to the U.S. Fish and Wildlife
Service within 5 days. The specimen may only be retained, disposed of,
or salvaged in accordance with written directions from the Service.
(iv) Engage in any act prohibited under paragraph (i)(1) of this
section with seeds of cultivated specimens, provided that a statement
that the seeds are of ``cultivated origin'' accompanies the seeds or
their container.
* * * * *
Martha Williams,
Director, U.S. Fish and Wildlife Service.
[FR Doc. 2023-24059 Filed 10-31-23; 8:45 am]
BILLING CODE 4333-15-P