Endangered and Threatened Wildlife and Plants; Removal of the Monito Gecko (Sphaerodactylus micropithecus) From the Federal List of Endangered and Threatened Wildlife, 52791-52800 [2019-20907]

Agencies

• Fish and Wildlife Service
• DEPARTMENT OF THE INTERIOR

[Federal Register Volume 84, Number 192 (Thursday, October 3, 2019)]
[Rules and Regulations]
[Pages 52791-52800]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-20907]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R4-ES-2017-0082; FXES11130900000C2-178-FF09E42000]
RIN 1018-BB76


Endangered and Threatened Wildlife and Plants; Removal of the 
Monito Gecko (Sphaerodactylus micropithecus) From the Federal List of 
Endangered and Threatened Wildlife

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Final rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), are removing 
the Monito gecko (Sphaerodactylus micropithecus) from the Federal List 
of Endangered and Threatened Wildlife due to recovery. This 
determination is based on a thorough review of the best available 
scientific and commercial information, which indicates that this 
species has recovered and the threats to this species have been 
eliminated or reduced to the point that the species no longer meets the 
definition of an endangered species or a threatened species under the 
Endangered Species Act of 1973, as amended. Accordingly, the 
prohibitions and conservation measures provided by the Act will no 
longer apply to this species.

DATES: This rule is effective November 4, 2019.

ADDRESSES: The proposed and final rules, the post-delisting monitoring 
plan, and the comments received on the proposed rule are available on 
the internet at https://www.regulations.gov in Docket No. FWS-R4-ES-
2017-0082 or https://ecos.fws.gov. Comments and materials we received, 
as well as supporting documentation we used in preparing this rule, are 
also available for public inspection by appointment, during normal 
business hours at: U.S. Fish and Wildlife Service, Caribbean Ecological 
Services Field Office, Road 301, Km. 5.1, Boquer[oacute]n, Puerto Rico 
00622; P.O. Box 491, Boquer[oacute]n, Puerto Rico 00622; or by 
telephone (787) 851-7297.

FOR FURTHER INFORMATION CONTACT: Edwin Mu[ntilde]iz, Field Supervisor, 
U.S. Fish and Wildlife Service, Caribbean Ecological Services Field 
Office (see ADDRESSES above). If you use a telecommunications device 
for the deaf (TDD), please call the Federal Relay Service at (800) 877-
8339.

SUPPLEMENTARY INFORMATION:

Executive Summary

Purpose of Regulatory Action

    The purpose of this action is to remove the Monito gecko from the 
Federal List of Endangered and Threatened Wildlife in title 50 of the 
Code of Federal Regulations (50 CFR 17.11(h)) (i.e., ``delisting'' it) 
based on its recovery.

Basis for Action

    We may delist a species if the best scientific and commercial data 
indicate the species is neither a threatened species nor an endangered 
species for one or more of the following reasons: (1) The species is 
extinct; (2) the species has recovered; or (3) the original data used 
at the time the species was classified were in error (50 CFR 424.11). 
Here, we have determined that the species may be delisted based on 
recovery as follows:
     Rat predation, the threat suspected to be the main cause 
of an apparent population decline for the Monito gecko (factor C), was 
eliminated by August 1999 when the last rat eradication campaign was 
completed by the Puerto Rico Department of Natural and Environmental 
Resources (PRDNER). From August 1999 to May 2016, no rats or other 
potential exotic predators have been detected on Monito Island.
     The species' apparent small population size (factor E), 
noted as a threat at the time of listing, may have been an artifact of 
bias as surveys were conducted under conditions when the species was 
not easily detectable. The Monito gecko is currently considered 
abundant and widely distributed on Monito Island.
     The Monito gecko and its habitat have been and will 
continue to be protected under Commonwealth laws and regulations 
(factor D). These existing regulatory mechanisms are adequate to 
protect the Monito gecko now and in the future.
    Despite potential climate change effects from a gradual warming 
trend for Puerto Rico, we expect the population to persist into the 
foreseeable future, especially with the current absence of other 
potential threats (e.g., habitat loss, disease, predation).

Previous Federal Actions

    On October 15, 1982, we published a final rule in the Federal 
Register (47 FR 46090) listing the Monito gecko as an endangered 
species and designating the entire island of Monito as critical 
habitat. On March 27, 1986, we published the Monito Gecko Recovery Plan 
(USFWS 1986, 18 pp.). The 5-year review, which was completed on August 
8, 2016 (USFWS 2016, 25 pp.), recommended delisting the species due to 
recovery. On January 10, 2018 (83 FR 1223), we published a proposed 
rule to delist the Monito gecko.
    For additional details on previous Federal actions, see discussion 
under the Recovery section below. Also see https://www.fws.gov/endangered/species/us-species.html for the species profile for this 
reptile.

Summary of Comments and Recommendations

    In the proposed delisting rule and draft post-delisting monitoring 
(PDM) plan published on January 10, 2018 (83 FR 1223), we requested 
that all interested parties submit written comments on the proposal and 
plan by March 12, 2018. We also contacted appropriate Federal and State 
agencies, scientific experts and organizations, and other interested 
parties and invited them to comment on the proposal. A newspaper notice 
inviting general public comments was published in Primera Hora (major 
local newspaper) and also announced using online and social media 
sources. We did not receive any requests for a public hearing.

Peer Review

    In accordance with our policy published in the Federal Register on 
July 1, 1994 (59 FR 34270), and the Office of Management and Budget's 
Final Information Quality Bulletin for Peer Review, dated December 16, 
2004, we solicited the expert opinions from five appropriate and 
independent

[[Page 52792]]

specialists regarding the science in the proposed rule and the draft 
PDM plan. The purpose of such review is to ensure that we base our 
decisions on scientifically sound data, assumptions, and analyses. We 
sent peer reviewers copies of the proposed rule and the draft PDM plan 
immediately following publication of the proposed rule in the Federal 
Register. We invited peer reviewers to comment, during the public 
comment period, on the specific assumptions and conclusions regarding 
the proposed delisting rule and draft PDM plan. We received responses 
from one of the peer reviewers.
    We reviewed all comments received from the peer reviewer for 
substantive issues and new information regarding the delisting rule and 
PDM plan for the Monito gecko. The peer reviewer generally concurred 
with our methods and conclusions and provided additional information, 
clarifications, and suggestions to improve the final delisting rule. 
Peer reviewer comments are summarized below and incorporated into the 
final rule as appropriate.
    (1) Comment: The peer reviewer mentions that the evidence for the 
success of the Monito rat eradications is strong, but not compelling. 
The reviewer specified that, given the multiple trips to Monito Island 
with uniformly negative results, eradication success is the most likely 
explanation, but longer term monitoring would elevate confidence in 
this conclusion.
    Our response: Since the rat eradication campaign in 1999, no rats 
have been detected on Monito Island. Based on the information available 
and consistent with the peer reviewer's interpretation of the evidence, 
is it highly unlikely there are still rats on Monito, unless there has 
been a reinvasion after May 2016, which is also unlikely. In addition, 
if rats had been present during our 2014 and 2016 trips we would likely 
have detected them, given the number of persons out at night searching 
for geckos, the relatively small size of the island, the rat detection 
devices used, and the scraps of food left out on purpose in the camp 
area. None of these methods produced even a suspicion of rats being 
present. Based on the best available information, the Service and its 
partners concluded that eradication was successful in 1998-1999.
    (2) Comment: The peer reviewer mentioned that the gecko abundance 
estimate is based on a model that is reasonable but that has not been 
validated for this population. Several other commenters questioned the 
validity of the model used for the population estimate. They stated 
that the model was inaccurate and the estimated abundance was extremely 
biased and does not meet the assumptions of the model specified. 
Specifically, the model is intended for multi-temporal replication. 
Commenters explained that the Service is relying on just a single visit 
survey in its erroneous estimates that have overly broad confidence 
limits and high statistical error.
    Our response: The Service used abundance modeling based on repeated 
surveys across multiple days across multiple sites. Specifically, we 
observed 84 geckos during 96 surveys among 40 plots across two nights. 
The high numbers of geckos detected (84) during the 96 surveys during 
the 2016 site visit was the first systematic attempt to survey the 
Monito gecko population. Recommendations for future survey efforts have 
been noted; for example, marking plots more visibly (Island 
Conservation 2016). During the development of the model and survey 
methods, the Service wanted methods and models that can be replicated 
in order to adjust and improve the abundance estimates accordingly over 
time (i.e., validate). Per our Post-Delisting Monitoring Plan, we 
recommend conducting surveys every other year for the next 5 years.
    For a complete review of the methods and results, a copy of Island 
Conservation (2016) report is available at https://www.regulations.gov 
in Docket No. FWS-R4-ES-2017-0082. In addition, the methods and a 
reproducible code set are freely available online at: https://github.com/nangeli1/Contracts.

Public Comments

    (1) Comment: One commenter asked the Service to explain the process 
for finding independent specialists when soliciting expert opinion for 
peer review.
    Our response: 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 sought the expert opinions 
of seven reviewers. We are required by our peer review policy to find 
at least three peer reviewers, and we often choose more than three if 
they are available. In doing so, the Service looked for experts in the 
species, including its life history, habitat and threats that it may 
face. The experts cannot have been involved in the production of the 
draft rule.
    (2) Comment: The peer reviewer stated that the Service does not 
have a population trajectory for this species, but rather only a single 
snapshot in time. Several other commenters also recommended that more 
surveys are needed to assess population trends before delisting, as 
well as more ecological studies.
    Our response: Gecko detections during 2014 and the 2016 survey 
provide substantial evidence that the species is consistently abundant 
and widespread across the island. Further, our analysis of the listing 
factors shows how the Service determined that the Monito gecko should 
be delisted, and survey information is just one of the parameters used 
to make that determination. Ultimately, there is no indication that any 
of the threats are operating on the population at levels that meet an 
endangered or threatened species as defined under the Act. In addition, 
conducting ecological studies was considered in the species Recovery 
Plan (1986). However, based on the most recent observations, 
achievement of the most critical recovery actions (i.e., rat 
eradication and survey), and our 5-factor analysis, we have determined 
that no additional ecological studies are needed to determine the 
listing status for this species. Future needs for studies, status 
evaluations, and recommendations will be addressed with the Post-
Delisting Monitoring Plan and its primary goal of monitoring to ensure 
the status of the species does not deteriorate and, if a substantial 
decline in the species population size or an increase in threats is 
identified, to enact measures to halt and reverse unfavorable trends.
    (3) Comment: Several commenters specified that there is evidence-
based support that climate change will impact S. micropithecus and 
provided scientific articles to support their claim.
    Our response: In our proposed rule, we analyzed the potential 
effects of climate-related sea-level rise on the Monito gecko and 
determined that it was not a threat to the species because the 
topography of Monito Island will insulate the species from the effects 
of sea-level rise. We asked the public to provide any data or new 
information particularly on the possible effects of climate change to 
the Monito gecko. Based on the comments and information received, we 
evaluated new information and conducted a thorough review of the 
relevant literature. We continue to conclude that climate change does 
not constitute a threat to the species to the extent that it is 
endangered or threatened throughout all or a significant portion of its 
range (Refer to Factor E, below, for a discussion of the

[[Page 52793]]

potential implications of climate change on the Monito gecko).
    (4) Comment: One commenter opined that lack of genetic analysis 
hinders the Service's ability to assess effective population size, 
inbreeding rates, deleterious alleles, and any proactive genetic rescue 
plans.
    Our response: The Service recognizes that this determination does 
not include a genetic analysis of the Monito gecko population but has 
determined that one is not needed. The fact that the species is found 
throughout Monito Island in the thousands, and that juveniles and 
gravid females were found (past and most current surveys), all 
demonstrate a large well-represented population with abilities to 
recover and adapt from disturbances. Thus, there do not seem to be any 
perceptible indications that a lack of genetic representation is 
causing species mortality or limiting the species' ability to adapt or 
reproduce. Still, any potential genetic rescue plan would need to 
consider that the Monito gecko population is endemic, closed to 
immigration from other Sphaerodactylus species, and has been isolated 
for millions of years.
    (5) Comment: Several commenters request the Service recognize the 
severe vulnerability of Monito Island and its inhabitants to 
catastrophic events such as hurricanes and fires.
    Our response: Catastrophic events such as fires or hurricanes were 
discussed under Factors A and E, respectively. Neither of these factors 
were found to be operating currently, or are expected to be found in 
the foreseeable future, on the Monito gecko population to require its 
continued listing under the Act. In addition, even though several 
hurricanes have potentially affected Monito Island in the past, the 
species remains abundant and widespread throughout the island. The 
recent Hurricane Maria (Sept. 2017), which caused extensive damage in 
Puerto Rico, did not cause significant damage to Monito Island.

Species Information

Biology and Life History

    The Monito gecko, Sphaerodactylus micropithecus, (Schwartz 1977, 
entire) is a small lizard (approximately 36 millimeters (1.42 inches) 
snout-vent length) with an overall pale-tan body and dark-brown 
mottling on the dorsal surface. It is closely related to the 
Sphaerodactylus macrolepis complex of the Puerto Rican Bank, but 
variation in dorsal pattern and scale counts confirm the 
distinctiveness of the species; probably resulting from a single 
invasion to Monito Island and its subsequent isolation (Schwartz 1977, 
p. 990, Dodd and Ortiz 1984, p. 768). Little is known about the biology 
of this species, including its diet, reproduction, or potential 
predators. Other more common Sphaerodactylus species in Puerto Rico eat 
a diverse content of small invertebrates, such as mites, springtails, 
and spiders (Thomas and Gaa Kessler 1996, pp. 347-362). Out of the 18 
individuals counted by Dodd and Ortiz (1983, p. 120), they found 
juveniles and gravid females suggesting that the species was 
reproducing. Dodd and Ortiz (1983, p. 121) suspected reproduction 
occurs from at least March through November as suggested by the egg 
found by Campbell in May 1974, by the gravid females found by Dodd and 
Ortiz (1982, p. 121) in August 1982, and the fact that Monito gecko 
eggs take 2 to 3 months to hatch (Rivero 1998, p. 89). During a plot 
survey in May 2016, two gravid females and several juveniles were found 
(USFWS 2016, p. 13). Potential natural predators of the Monito gecko 
may include the other native lizard Anolis monensis and/or the Monito 
skink (Spondilurus monitae).

Distribution and Habitat

    The Monito gecko is restricted to Monito Island, an isolated island 
located in the Mona Passage, about 68 km (42.3 mi) west of the island 
of Puerto Rico, 60 km (37.3 mi) east of Hispaniola and about 5 km (3.1 
mi) northwest of Mona Island (USFWS 1986, p. 2). Monito Island is a 
flat plateau surrounded by vertical cliffs rising about 66 m (217 ft) 
with no beach and is considered the most inaccessible island within the 
Puerto Rican archipelago (Garcia et al. 2002, p. 116). With an 
approximate area of 40 acres (c.a. 16 hectares) (Woodbury et al. 1977, 
p. 1), Monito Island is part of the Mona Island Reserve, managed for 
conservation by the PRDNER (no date, p. 2). The remoteness and 
difficulty of access to Monito Island make studying the Monito gecko 
difficult (Dodd 1985, p. 2).
    The only life zone present on Monito Island is subtropical dry 
forest (Ewel and Whitmore 1973, p. 10). In this life zone, the Monito 
gecko has been found in areas characterized by loose rock sheets or 
small piles of rocks, exposed to the sun, and with little or no 
vegetation cover. Vegetation may or may not be associated with these 
areas. On Monito Island, such areas include small groves of Guapira 
discolor (barrehorno), Pithecellobium unguis-cati (escambrn colorado), 
or Capparis flexuosa (palo de burro) where some leaf litter is present; 
areas with loose rocks on the ground; or rock sheets that provide shady 
refuges, and numerous regions where large pieces of metal (remnant 
ordnance) lay on the ground (Ortiz 1982, p. 2). Being a small, ground-
dwelling lizard, the Monito gecko, like other members of its genus, is 
usually found under rocks, logs, leaf litter, and trash (Rivero 1998, 
p. 89).

Population Size and Trends

    When the species' recovery plan was completed in 1986, only two 
island-wide surveys had been completed (Dodd and Ortiz 1983, entire; 
Hammerson 1984, entire), with the higher count from Dodd and Ortiz 
(1983, p. 120) reporting a total of 18 geckos during a 2-day survey. 
During both of these surveys, all geckos were found during the day and 
under rocks. Subsequent surveys of variable length and area covered 
detected from 0 to 13 geckos during the day as well (PRDNER 1993, pp. 
3-4; USFWS 2016, p. 9).
    These previous attempts to survey for the Monito gecko are 
considered underestimates, because the surveys were done during the day 
when the species is more difficult to detect: It seems to be less 
active and mostly hiding under rocks, debris, crevices, or other 
substrates. Although geckos in the Sphaerodactylinae group are 
considered mostly diurnal or crepuscular (Rivero, p. 89; Pianka and 
Vitt 2003, p. 185), we suspect that the Monito gecko is more active at 
night and thus easier to detect during night surveys. This nocturnal 
behavior was confirmed during a May 2014 rapid assessment and a May 
2016 systematic survey. During the May 2014 rapid assessment, at least 
one gecko was seen during each of the three nights of the trip; some 
encounters were opportunistic, and others occurred while actively 
searching for the species (USFWS 2016, p. 9). In fact, no geckos were 
seen during daylight hours. Geckos were seen on exposed substrates and 
not hidden under rocks or litter, although some were seen within leaf 
litter mixed with rocks under a Ficus citrifolia tree. Geckos were 
observed escaping into the cracks and solution holes of the limestone 
rock.
    The May 2016 systematic gecko survey involved setting up of 40 
random plots on Monito Island (USFWS 2016, p. 10). Each plot was 20 m x 
20 m (400 m\2\), so that the survey covered a total of 16,000 m\2\ or 
approximately 11 percent of Monito Island. Four two-person teams 
visited 10 plots each. Each observer surveyed each plot independently. 
All sites were surveyed at least twice, and all took place during the 
night. A total of 84 geckos were observed during 96 surveys among the

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40 plots, most on exposed rock. Only 8 out of the 84 counted were found 
under a rock or other substrate; all others were out during the night. 
Only two geckos were opportunistically found during the day while 
observers were turning rocks and dry logs.
    Gecko occupancy and abundance were estimated using a standard 
mathematical population model accounting for the abundance and 
detection bias that allows individuals to go unseen during surveys 
(Island Conservation (IC) 2016, p. 5). Occupancy of the geckos on 
Monito Island was determined to be 27.8 percent (confidence interval 
11.3-68.6 percent). The mean number of geckos per plot was 73.3 (Range: 
1-101). The abundance model indicates a total of 1,112 geckos present 
within the surveyed plots (95 percent confidence interval: 362-2,281). 
Extrapolated across the entire island, Monito Island hosts 
approximately 7,661 geckos (50 percent confidence interval: 5,344-
10,590).

Recovery and Recovery Plan Implementation

    Section 4(f) of the Act directs us to develop and implement 
recovery plans for the conservation and survival of threatened and 
endangered species unless we determine that such a plan will not 
promote the conservation of the species. Recovery plans are not 
regulatory documents and are instead intended to establish goals for 
long-term conservation of a listed species, define criteria that are 
designed to indicate when the threats facing a species have been 
removed or reduced to such an extent that the species may no longer 
need the protections of the Act, and provide guidance to our Federal, 
State, and other governmental and nongovernmental partners on methods 
to minimize threats to listed species. There are many paths to 
accomplishing recovery of a species, and recovery may be achieved 
without all recovery criteria being fully met. For example, one or more 
criteria may have been exceeded while other criteria may not have been 
accomplished or become obsolete, yet the Service may judge that, 
overall, the threats have been minimized sufficiently, and the species 
is robust enough, to reclassify the species from endangered to 
threatened or perhaps delist the species. In other cases, recovery 
opportunities may have been recognized that were not known at the time 
the recovery plan was finalized. These opportunities may be used 
instead of methods identified in the recovery plan.
    Likewise, information on the species may subsequently become 
available that was not known at the time the recovery plan was 
finalized. The new information may change the extent that criteria need 
to be met for recognizing recovery of the species. Recovery of species 
is a dynamic process requiring adaptive management that may, or may 
not, fully follow the guidance provided in a recovery plan.
    The following discussion provides a brief review of recovery 
planning and implementation for the Monito gecko, as well as an 
analysis of the recovery criteria and goals as they relate to 
evaluating the status of the taxon.
    The Monito Gecko Recovery Plan (Plan) was approved on March 27, 
1986 (USFWS 1986, entire). The objective of the Plan was to conduct a 
systematic status survey and ecological study of the species, and to 
reevaluate the species' status and formulate a quantitative recovery 
level and specific recovery actions (USFWS 1986, p. 7). This Plan is 
considered outdated and does not contain recovery criteria that could 
lead to delisting the Monito gecko. However, the Plan does provide 
recovery objectives that, when accomplished, would aid in developing 
such criteria. No quantitative recovery level was defined due to the 
lack of data on historical population levels, population trends, and 
apparent historical population size. The objectives were accomplished 
as follows:

Recovery Actions

    The Plan identifies five primary recovery actions:
    (1) Determine the status of the present population;
    (2) Conduct basic ecological studies;
    (3) Determine extent, if any, of predation and competition by rats 
and other native lizards (see Factor C);
    (4) Update the Plan; and
    (5) Continue protection of the present population.
    The following discussion provides specific details for each of 
these actions.
    Recovery action 1: Determine the status of the species.
    From 1982 to 1993, several Monito gecko surveys were conducted 
(USFWS 2016, p. 9). However, some of these surveys were either done 
before the Plan was completed (USFWS 1986) or did not provide enough 
information to answer the population objectives of the Plan, and 
current information (see Population Size and Trends above) suggests 
that surveys underestimated the number of geckos. Data from the 2014 
rapid assessment and the 2016 systematic plot survey show that, 
overall, the Monito gecko is abundant across the whole island and 
numbers in the thousands, indicating a large healthy population, as 
specified in the Species Information section above.
    Recovery action 2: Conduct basic ecological studies.
    Besides the population survey efforts, no basic ecological studies 
have been conducted for the Monito gecko. Conducting ecological 
studies, as described in the Plan (USFWS 1986, pp. 7-8), is not crucial 
to further assess the species' listing status. There is no indication 
that ecological factors such as habitat preferences (species occurs 
throughout the island) and fluctuations in reproductive biology or 
activity patterns (both unknown), are critical for the species' listing 
status. The adjustment of surveys from diurnal to nocturnal was a key 
factor for researchers to discover in order to obtain reliable data and 
provide optimal population information. We will further discuss any 
possible needs of ecological evaluations in relation to post-delisting 
monitoring with our partners, but we will likely not need detailed 
research on the gecko's ecology based on the status of threats in its 
native habitat on Monito Island.
    Recovery action 3: Determine the extent, if any, of predation and 
competition by rats and native reptiles.
    At the time of listing, the presence of rats on Monito Island was 
identified as the main threat to the Monito gecko. This threat was 
suspected to be the main cause of an apparent population decline for 
the Monito gecko, since rats are effective predators and are known to 
feed on both lizards and lizard eggs (Dodd and Ortiz 1983, p. 120; Case 
and Bolger 1991, pp. 273-278). However, the net effect, if any, of the 
potential rat predation on the geckos is debatable. For example, in 
comments quoted in the final listing rule (47 FR 46091, October 15, 
1982), Dr. H. Campbell indicated that the scarcity of the Monito geckos 
was an artifact of the intense predation by black rats (Rattus rattus), 
while Dr. A. Schwartz expressed doubts that rats could have any effect 
on the gecko or its eggs. Dodd and Ort[iacute]z (1983, p. 121) also 
explained that, during their surveys, predator pressure on the gecko 
could not be proven and that more studies were needed to determine if 
rats or other predators do affect the Monito gecko. The potential 
effect of rats on two other relatively common small geckos 
(Sphaerodactylus monensis and Sphaerodactylus levinsi) on nearby Mona 
and Desecheo Islands (respectively) is also unknown. Nevertheless, 
there is ample evidence that the Monito gecko would fare better without 
rats (Case and Bolger 1991, entire; Towns et al. 2006, entire; Jones

[[Page 52795]]

et al. 2016, entire; Thibault et al. 2017, entire).
    In October 1992, the PRDNER began a black rat eradication and 
survey project on Monito Island to benefit native and endemic species 
on that Island (Garc[iacute]a et al. 2002, p. 116). The eradication 
campaign continued in March 1993 with poisoning (rodenticide) and snap 
traps to assess changes in the rat population. A second eradication 
campaign started in October 1998, with three eradication events at 4-
month intervals, and again using, in addition to snap traps, chew 
blocks (i.e., soft wood pieces soaked in canola oil) as a monitoring 
tool.
    Garc[iacute]a et al. (2002, pp. 117-118) evaluated the status of 
the rat population seven times during the first campaign and five times 
during the second campaign. Since the completion of the second 
eradication campaign (August 1999), no rats have been detected on 
Monito Island. Garc[iacute]a et al. (2002, p. 118) concluded that in 
order to be certain that eradication had been achieved, it was 
essential to continue an appropriate rat monitoring program on the 
island, and recommended using chew blocks. However, no systematic rat 
monitoring has been implemented on the island since September 1999. 
Nonetheless, during a seabird blood sampling trip in August 2000, 
Anderson and Steeves (2000, p. 1) reported not seeing any rats on 
Monito Island, as did subsequent PRDNER bird survey trips in 2003.
    On May 2014, the Service organized an expedition to Monito Island 
with the PRDNER in order to confirm the eradication of black rats from 
the island, and to evaluate the status of and threats to the Monito 
gecko. The Service and the PRDNER placed 27 snap traps and 70 chew 
blocks distributed along transects covering 870 meters in length (USFWS 
2016, p. 7). In addition, some food items (i.e., watermelon, left-over 
canned food) were intentionally left exposed and available for rats. No 
signs of rats were detected on these available sources during this 4-
day/3-night trip. During surveys conducted in May 2016, the Service and 
the PRDNER also placed 80 chew blocks, two within each gecko sampling 
plot (USFWS 2016, p. 10). No rats were seen or detected with the chew 
blocks during this 5-day/4-night trip. This is a marked contrast from 
when the species was listed in 1982, when rats were observed island-
wide at all times during a 2-day expedition (47 FR 46090, October 15, 
1982).
    In short, although it cannot be ascertained when the last rat died, 
Monito Island appears to have been rat free since August-September 
1999. Thus, the suspected main threat to the species has not been 
present for at least the past 18 years.
    Other lizards (i.e., Anolis monensis and Spondilurus monitae, 
formerly Mabuya mabouya sloani) that naturally occur on the Island may 
also prey on the Monito gecko. These other species are considered 
diurnal (active during the day), while the Monito gecko is considered 
nocturnal (active during the night). Determining the extent of these 
potential predator-prey interactions would be challenging. However, 
this should no longer be necessary, as the species has persisted 
despite potential predatory threats.
    Recovery action 4: Update Recovery Plan.
    Because of the information on threats and recovery progress that is 
provided in the Monito gecko 5-year review (USFWS 2016) and this final 
rule, the Monito gecko no longer meets the definition of an endangered 
or threatened species. Therefore, a formal update of the 1986 Plan is 
not needed.
    Recovery action 5: Continue protection of the present population.
    Monito Island has been protected by the PRDNER as a nature reserve 
since 1986 (PRDNER, no date, p. 2). There are no permanent human 
residents on Monito Island and access is allowed only under special 
permits issued by the PRDNER, which also maintains a ranger detachment 
and biologist on nearby Mona Island. Monito Island is also visited by 
illegal immigrants. The frequency of these events varies from year to 
year, and illegal immigrants are evacuated fairly quickly by the U.S. 
Coast Guard. Furthermore, the impacts of these visitations seem to be 
minimal (see discussion below).

Summary of Factors Affecting the Species

    Section 4 of the Act and its implementing regulations (50 CFR part 
424) set forth the procedures for listing, reclassifying, or removing 
species from the Federal List of Endangered and Threatened Species. 
``Species'' is defined by the Act as including any species or 
subspecies of fish or wildlife or plants, and any distinct vertebrate 
population segment of fish or wildlife that interbreeds when mature (16 
U.S.C. 1532(16)). Once the species is determined, we then evaluate 
whether that species may be an endangered species or a threatened 
species because of any of one or a combination of the five factors 
described in section 4(a)(1) of the Act:
    (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range;
    (B) Overutilization for commercial, recreational, scientific, or 
educational purposes;
    (C) Disease or predation;
    (D) The inadequacy of existing regulatory mechanisms; or
    (E) Other natural or manmade factors affecting its continued 
existence.
    We must consider these same five factors in reclassifying or 
delisting a species. In other words, for species that are already 
listed as endangered or threatened, the analysis for a delisting due to 
recovery must include an evaluation of the threats that existed at the 
time of listing, the threats currently facing the species, and the 
threats that are reasonably likely to affect the species in the 
foreseeable future following the delisting or downlisting and the 
removal of the Act's protections.
    The following discussion examines the factors that were believed to 
affect the Monito gecko at the time of its listing, are currently 
affecting it, or are likely to affect the Monito gecko within the 
foreseeable future.

Factor A. The Present or Threatened Destruction, Modification, or 
Curtailment of Its Habitat or Range

    At the time of listing (47 FR 46090, October 15, 1982), the 
destruction, modification, or curtailment of its habitat was not 
considered a threat to the Monito gecko. In 1940, the U.S. Government 
acquired Monito Island, and the entire island was used by the Air 
Corps/U.S. Air Force as a high-level radar bombing and gunnery range 
(Parsons Corp. 2010, pp. 2-5). In 1961, Monito Island was declared 
surplus and was returned to the Commonwealth of Puerto Rico in 
September 1965 (Parsons Corp. 2010, pp. 2-5). Monito Island is managed 
by the PRDNER for conservation as part of the Mona Island Reserve 
(PRDNER, no date, p. 2). The final listing rule indicated that there 
were no plans to continue to use Monito Island for bombing practices at 
the time, and any major alteration of the island could be detrimental 
to the continued survival of the Monito gecko. In fact, the large 
amount of scattered debris on Monito Island suggests significant 
historical habitat modification from bombing activities (USFWS 1986, p. 
5).
    A Monito Island site inspection was conducted in August 2009 
(Parsons Corp. 2010, entire). A qualitative reconnaissance and 
munitions constituents sampling was performed to confirm the range 
location and to evaluate the potential presence of munitions and 
explosives of concern (Parsons Corp. 2010, p. ES-1). Although 
unexploded ordnance (UXO) and munitions debris was found on Monito

[[Page 52796]]

Island, immediate munitions removal actions were not warranted.
    The potential for future UXO detonation activities may have an 
effect on the Monito gecko and its critical habitat. Since Monito 
Island is a natural reserve, all activities must be coordinated with 
the PRDNER. The Service has been conducting informal consultations with 
the U.S. Army Corps of Engineers in order to develop species-specific 
standard operating procedures (SOPs) for the Monito gecko and other 
federally listed species that occur on Monito Island. These site-
specific SOPs would be considered the appropriate conservation measures 
required to avoid and minimize potential adverse effects on the species 
or its critical habitat. Based on the current consultation, the 
magnitude of threat of these future U.S. Army Corps of Engineers' 
actions on the Monito gecko is considered minimal and non-imminent 
(USCOE 2017).
    Monito Island receives illegal immigrants, usually from the western 
islands of Cuba and Hispaniola, that are trying to enter U.S. 
territory. The PRDNER has stated that illegal immigrants sometimes 
light fires on Monito Island in order to be detected and rescued. This 
information was documented during the May 2016 trip, where two recent 
fire pits were found, along with a small pile of firewood cuttings, on 
the south-southeast side of the island on exposed rock with no 
vegetation in the immediate vicinity. The presence of fire pits on 
Monito Island had not been documented in the past. At least for the two 
fire pits found in May 2016, their placement and construction 
demonstrates these were controlled fires and their intention was not of 
criminal nature. Although there is no information available on the 
frequency and damage these fires may be causing, based on what was 
documented in May 2016, the potential effects of such fires may also be 
considered minimal. To date, there is no indication that any potential 
fires have spread throughout the Island.

Factor B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    The final listing rule (47 FR 46091, October 15, 1982) mentioned 
that, because of the rarity of the Monito gecko, removal of specimens 
could be detrimental. At present, we are not aware of any individuals 
taken after listing for commercial, recreational, scientific, or 
educational purposes. The remoteness and difficult access of Monito 
Island limits any collecting efforts. In addition, access is only 
allowed under special permits issued by the PRDNER, mostly for 
research, security, or management purposes. Furthermore, the Monito 
gecko's apparent rarity may have been an artifact of sampling bias, 
because surveys from 1982 to 1993 were done during daylight hours when 
the species is mostly hiding and the species has a low detection 
probability (see Species Information section).

Factor C. Disease or Predation

    The final listing rule (47 FR 46091, October 15, 1982) indicates 
that the presence of large numbers of introduced black rats was thought 
to be the major factor in the precarious state of the Monito gecko 
because, although predation by black rats on this species has not been 
confirmed, rats are predaceous and are known to feed on both lizards 
and lizard eggs (Dodd and Ortiz 1983, p. 120; Case and Bolger 1991, pp. 
273-278). Thus, predation by rats was considered a possible cause of 
population decline for the Monito gecko (USFWS 1986, p. 5). As 
previously explained above under Recovery Action 3, Monito Island has 
been rat free since August-September 1999. Thus, the main threat to the 
species has not been present for at least the past 18 years.
    Although Monito Island is currently rat free, there is still the 
possibility that rats could reach the island again. Rats may be 
transferred from Mona Island by floating debris or more likely by human 
means. In addition to illegal immigrants, as discussed above, there is 
limited evidence of public use of Monito Island for recreational or 
unknown purposes. Although it is logistically difficult to disembark on 
the island and prohibited because of unexploded ordinances from the 
previous military activities, these disembarking events could increase 
the chance of invasion and establishment of rats or other exotic 
species. However, this possibility is considered very low. The rat 
eradication campaign was completed in 1999, and 18 years later, no rats 
have been found.
    Ortiz (1982, p. 7) included the endemic Monito skink Spondilurus 
monitae (formerly Mabuya mabouya sloani) as a potential predator of the 
Monito gecko. Other species of Mabuya feed primarily on small 
invertebrates, but the diversity of prey types in stomach contents, 
including small vertebrates, indicates that some skink species (such as 
M. bistriata) most likely feed on any moving animal of the appropriate 
size (Vitt and Blackburn 1991, p. 920). Mabuya mabouya live in places 
where Sphaerodactylus abound (Rivero 1998, p. 106) and it is probable 
that geckos constitute an important food item for this skink. During 
the 2016 trip, biologists observed one adult skink active at night 
within the same exposed rock habitat used by the Monito gecko (i.e., 
exposed karst rock with lots of crevices and holes). It is also highly 
probable that another native lizard, Anolis monensis, will prey on the 
Monito gecko as well, except that Anolis are considered diurnal. The 
Monito gecko's trait of tail autotomy (tail loss) is certainly an 
effective predator defense mechanism (Pianka and Vitt 2003, p. 76). 
During our May 2014 site visit, 2 out of the 8 geckos captured for 
measurements were missing the tips of their tails, and during May 2016, 
only 5 geckos out of the 84 seen had missing tail parts. Although 
difficult to determine, this suggests natural predation pressure from 
the two other native lizard species mentioned above is low.

Factor D. The Inadequacy of Existing Regulatory Mechanisms

    When the Monito gecko was listed (47 FR 46091; October 15, 1982), 
the species did not have any other statutory or regulatory protections. 
Now, territorial laws and regulations protect the Monito gecko. In 
1999, the Commonwealth of Puerto Rico enacted Law No. 241-1999, known 
as the New Wildlife Law of Puerto Rico (Nueva Ley de Vida Silvestre de 
Puerto Rico). The purpose of this law is to protect, conserve, and 
enhance both native and migratory wildlife species; declare property of 
Puerto Rico all wildlife species within its jurisdiction; provide 
provisions to issue permits; regulate hunting activities; and regulate 
exotic species, among other actions. In 2004, the PRDNER approved 
Regulation 6766--to regulate the management of threatened and 
endangered species in Puerto Rico (Reglamento 6766--Reglamento para 
Regir el Manejo de las Especies Vulnerables y en Peligro de 
Extinci[oacute]n en el Estado Libre Asociado de Puerto Rico), including 
the Monito gecko, which was listed as endangered. Article 2.06 of this 
regulation prohibits collecting, cutting, removing, among other 
activities, listed animals within the jurisdiction of Puerto Rico. 
There is no evidence that either the law or the regulation is not being 
adequately implemented.
    Additionally, the PRDNER has managed Monito Island as a natural 
reserve since 1986, protecting its wildlife and vegetation. Monito 
Island is managed for conservation because it harbors one of the 
largest seabird nesting colonies in the Caribbean, in addition to other 
endemic and federally listed species like the Higo chumbo cactus 
(Harrisia portoricensis) and the

[[Page 52797]]

yellow-shouldered blackbird (Agelaius xanthomus). No human permanent 
residents live on the island, and public access is prohibited. The best 
available information indicates that Monito Island will remain 
permanently protected as a nature reserve and managed for conservation. 
In addition, Monito Island harbors additional species protected by the 
ESA and the Migratory Bird Treaty Act. Any potential future federal 
actions on Monito Island will still require consultation with the USFWS 
for those species (e.g., Harrisia cactus, Yellow-shouldered black 
bird), thereby potentially also benefiting the Monito gecko from 
conservation measures developed for those other species.

Factor E. Other Natural or Manmade Factors Affecting Its Continued 
Existence

    In listing the Monito gecko, we considered as a factor the species' 
extremely small population size (47 FR 46090, October 15, 1982). As 
previously explained in Species Information and Recovery and Recovery 
Plan Implementation, the Monito gecko is a small and cryptic species 
and difficult to detect, especially during the day. However, all of the 
historical surveys documented (USFWS 2016, p. 9) were done during 
daylight hours, when the species is apparently less active, safely 
hiding from diurnal native reptile predators, and/or exhibiting 
behavioral adaptations to avoid the hot temperatures within its xeric 
dry forest environment. As discussed above (see Population Size and 
Trends), these and other biases cause us to question the validity of 
these historical surveys. In contrast, as also discussed above (see 
Population Size and Trends), the best available population estimate for 
the species, completed during the May 2016 systematic plot survey, 
shows that the Monito gecko is widely distributed throughout Monito 
Island and gecko abundance appears to number in the thousands, 
indicating a large well-represented population (IC 2016, pp. 5-6). Our 
post-delisting monitoring will demonstrate the continued recovery of 
this species. In general, lizard populations remain fairly stable and 
are influenced by predation and amount of resources available, and 
predation and competition usually result in populations existing below 
their carrying capacity (Pianka and Vitt 2003, p. 64). Based on the May 
2014 and 2016 observations and results, there is no indication that 
limited resources are acting on the population to warrant listing under 
the Act.
    Potential sea level rise as a result of climate change is not a 
threat to this species or its habitat, because the Monito gecko is 
found only on Monito Island, which is 66 m (217 ft) above sea level and 
has no beach areas. The current rate of sea level rise in the Caribbean 
is 10 cm (3.9 inches) per century, with more specific sea level rise 
estimates for Puerto Rico ranging from 0.07 to 0.57 meters (m) (0.20 to 
1.87 feet) above current sea level by the year 2060 and between 0.14 to 
1.70 m (0.40 to 5.59 feet) by the year 2110 (Puerto Rico Climate Change 
Council 2013, p. 64). Thus, the habitat occupied by the Monito gecko 
will remain well above the area of Monito Island predicted to be 
affected by sea-level rise in the foreseeable future.
    Hurricanes, such as the recent Hurricanes Irma and Maria are not 
considered a threat to the Monito gecko in part because the island is 
66 m above sea level. The vegetation on the island is short and 
therefore hurricane impacts are expected to be minimal. Additionally, 
the Monito gecko is adapted to living under cover mostly during the day 
when the species seems to be less active. Typical forms of cover 
include rocks, debris, crevices, or other substrates.
    We further evaluated the potential effects of the predicted 
scenario of a gradual trend toward a dryer and hotter climate for 
Puerto Rico (Henareh et al. 2016, p. 265; Bhardwaj et al. 2018, pp. 
133-134). To a certain extent, evaluating the vulnerability of the 
Monito gecko to climate change would require linking the magnitude of 
changes (i.e., temperature and humidity) with the physiological 
response of the species to those changes (Deutsch et al. 2008, p. 6668; 
Huey et al. 2009, p. 1; Glick et al. 2011, pp. 39-43; Pacifici et al. 
2015, p. 215). For example, the fact that Sphaerodactylus are 
particularly vulnerable to overheating and desiccation is an important 
criterion to evaluate.
    Based on the available information, the Monito gecko should have 
low evaporative water loss rates, with behavioral adaptions similar to 
other Sphaerodactylus (or other lizards) that exploit arid 
microhabitats (Snyder 1979, p. 110; Dunson and Bramham 1981, pp. 257-
258; Nava 2001, pp. 461-463; L[oacute]pez-Ortiz and Lewis 2004, p. 438; 
Nava 2004, pp. 18-26; Steinberg et al. 2007, pp. 334-335; Turk et al. 
2010, pp. 128-129; Bentz et al. 2011, pp. 46-47; Allen and Powell 2014, 
pp. 594-596). Research suggests that these tiny lizards have behavioral 
and physiological traits that allow them to acclimate to and survive 
under each particular local environment and climate. In the case of the 
Monito gecko, the species usually hides and is undetectable during the 
day (unless an active search of turning rocks and debris is conducted) 
and shifts to a more active and detectable lifestyle during the night. 
This is consistent with microhabitat selection and activity patterns 
exhibited by other Sphaerodactylus lizards to minimize exposure to 
physiologically challenging diurnal conditions of lower humidity and 
higher temperatures. Cover during the day not only provides insulation 
from higher temperatures, but also protection from predators such as 
the relatively abundant Anole lizard on Monito Island. In addition, 
Sphaerodactylus eggs are considered extremely resistant to dessication 
(Dunson and Bramham 1981, p. 255).
    Without any specific climate change studies for the Monito gecko, 
it is difficult to predict with certainty how the Monito gecko will 
respond to predicted climate change scenarios and how they might affect 
the species' fitness and viability. Some researchers suggest that 
climate change will increase the thermal stress on tropical lizards, 
suggesting a detrimental effect on the basic physiological functions of 
these ectotherms (Deutsch 2008, entire; Tewksbury 2008, entire; Huey et 
al. 2009, entire). However, with the current absence of other potential 
threats (e.g., habitat loss, disease, rat predation, etc.) and the 
perpetual legal protection of the species and its habitat as a nature 
reserve, the Monito gecko should have the best opportunity to survive 
and adapt well past the foreseeable future. Thus, we do not expect the 
Monito gecko to be endangered nor threatened currently or in the 
foreseeable future by potential climate change effects.

Determination of Species Status

    Under section 4(a)(1) of the Act, we determine whether a species is 
an endangered species or threatened species because of any one or a 
combination of the following: (A) The present or threatened 
destruction, modification, or curtailment of its habitat or range; (B) 
Overutilization for commercial, recreational, scientific, or 
educational purposes; (C) Disease or predation; (D) The inadequacy of 
existing regulatory mechanisms; or (E) Other natural or manmade factors 
affecting its continued existence. The Act defines an endangered 
species as any species that is ``in danger of extinction throughout all 
or a significant portion of its range'' and a threatened species as any 
species ``which is likely to become an endangered species within the 
foreseeable future throughout all or a significant portion of its 
range.''

[[Page 52798]]

Monito Gecko--Determination of Status Throughout All of Its Range

    As required by section 4(a)(1) of the Act, we conducted a review of 
the status of this species and assessed the five factors to evaluate 
whether it is in danger of extinction currently or likely to become so 
in the foreseeable future throughout all of its range. The Monito gecko 
is endemic to Monito Island, a small island (approx. 40 acres; 16.2 
hectares) off the west coast of Puerto Rico, and it has not been 
introduced elsewhere. There are no landscape barriers within Monito 
Island that might be of biological or conservation importance. The most 
recent survey found that the species occurs across most of the Island. 
The basic ecological components required for the species to complete 
its life cycle are considered present throughout Monito Island. We 
found that Monito gecko populations are persistent with an estimate of 
approximately 7,661 geckos (50 percent confidence interval: 5,344-
10,590). During our analysis, we found that impacts thought to be 
threats at the time of listing (primarily predation by rats, factor C) 
are either not as significant as originally anticipated or have been 
eliminated or reduced since listing, and we do not expect any of these 
conditions to substantially change post-delisting and into the 
foreseeable future, nor do we expect climate change to affect this 
species in the foreseeable future. We conclude that the previously 
recognized impacts (i.e., rat predation, small population size) to the 
Monito gecko no longer threaten the species, such that the species is 
no longer in danger of extinction throughout all of its range now or in 
the foreseeable future. In order to make this conclusion, we analyzed 
the five threat factors used in making Endangered Species Act listing 
(and delisting) decisions. This analysis indicates that the Monito 
gecko is not in danger of extinction throughout all of its range, nor 
is it likely to become so in the foreseeable future.

Monito Gecko--Determination of 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 (SPR). Where the best available information allows the 
Services to determine a status for the species rangewide, that 
determination should be given conclusive weight because a rangewide 
determination of status more accurately reflects the species' degree of 
imperilment and better promotes the purposes of the Act. Under this 
reading, we should first consider whether the species warrants listing 
``throughout all'' of its range and proceed to conduct a ``significant 
portion of its range'' analysis if, and only if, a species does not 
qualify for listing as either an endangered or a threatened species 
according to the ``throughout all'' language.
    Having determined that the Monito gecko is not in danger of 
extinction now or likely to become so in the foreseeable future 
throughout all of its range, we now consider whether it may be in 
danger of extinction or likely to become so in the foreseeable future 
in an SPR. The range of a species can theoretically be divided into 
portions in an infinite number of ways, so we first screen the 
potential portions of the species' range to determine if there are any 
portions that warrant further consideration. To do the ``screening'' 
analysis, we ask whether there are portions of the species' range for 
which there is substantial information indicating that: (1) The portion 
may be significant; and (2) the species may be, in that portion, either 
in danger of extinction or likely to become so in the foreseeable 
future. For a particular portion, if we cannot answer both questions in 
the affirmative, then that portion does not warrant further 
consideration and the species does not warrant listing because of its 
status in that portion of its range. We emphasize that answering these 
questions in the affirmative is not a determination that the species is 
in danger of extinction or likely to become so in the foreseeable 
future throughout a significant portion of its range--rather, it is a 
step in determining whether a more detailed analysis of the issue is 
required.
    If we answer these questions in the affirmative, we then conduct a 
more thorough analysis to determine whether the portion does indeed 
meet both of the SPR prongs: (1) The portion is significant and (2) the 
species is, in that portion, either in danger of extinction or likely 
to become so in the foreseeable future. Confirmation that a portion 
does indeed meet one of these prongs does not create a presumption, 
prejudgment, or other determination as to whether the species is an 
endangered species or threatened species. Rather, we must then 
undertake a more detailed analysis of the other prong to make that 
determination. Only if the portion does indeed meet both SPR prongs 
would the species warrant listing because of its status in a 
significant portion of its range.
    At both stages in this process--the stage of screening potential 
portions to identify any portions that warrant further consideration 
and the stage of undertaking the more detailed analysis of any portions 
that do warrant further consideration--it might be more efficient for 
us to address the ``significance'' question or the ``status'' question 
first. Our selection of which question to address first for a 
particular portion depends on the biology of the species, its range, 
and the threats it faces. 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 second question for 
that portion of the species' range.
    For Monito gecko, we chose to evaluate the status question (i.e., 
identifying portions where the Monito gecko may be in danger of 
extinction or likely to become so in the foreseeable future) first. To 
conduct this screening, we considered whether the threats are 
geographically concentrated in any portion of the species' range at a 
biologically meaningful scale. If a species is not in danger of 
extinction or likely to become so in the foreseeable future throughout 
all of its range and the threats to the species are essentially uniform 
throughout its range, then the species would not have a greater level 
of imperilment in any portion of its range than it does throughout all 
of its range and therefore no portions would qualify as an SPR.
    We examined the following threats: The destruction and modification 
of habitat by humans and exotic foreign species introduced to the 
Monito Island, such as rats and mice, including cumulative effects. We 
found no concentration of threats in any portion of the Monito gecko's 
range at a biologically meaningful scale. Since we found no portions of 
the species' range where potential threats are significantly 
concentrated or substantially greater than in other portions of its 
range, we did not identify any portions where the species may be in 
danger of extinction or likely to become so in the foreseeable future. 
Therefore, no portions warrant further consideration through a more 
detailed analysis, and the species is not in danger of extinction or 
likely to become so in the foreseeable future in any significant 
portion of its range. Our approach to analyzing SPR in this 
determination is consistent with the court's holding in Desert 
Survivors v. Department of the Interior, No. 16-cv-01165-JCS, 2018 WL 
4053447 (N.D. Cal. Aug. 24, 2018).
    Our review of the best available scientific and commercial 
information

[[Page 52799]]

indicates that the Monito gecko is not in danger of extinction nor 
likely to become an endangered species within the foreseeable future 
throughout all or a significant portion of its range. Therefore, we 
find that listing the Monito gecko as an endangered species or a 
threatened species under the Act is not warranted at this time.

Conclusion and Determination

    The Monito gecko has demonstrated the ability to persist despite 
changing environmental conditions over time from both anthropogenic and 
natural disturbances. Although the Monito gecko population is 
considered to have low redundancy (i.e., one population endemic to 
Monito Island), no risk of extirpation was identified and no other 
populations outside of Monito Island are needed for its recovery. In 
addition, the fact that the species was found throughout the Island, 
gecko abundance is in the thousands, and past and current occurrence of 
juveniles and gravid females, indicates a large, well-represented 
population with demonstrated abilities to recover and adapt from 
disturbances.
    Because the Monito gecko population is considered self-sustaining, 
contains a large number of individuals, and has demonstrated high 
resilience and viability, we expect this population to persist into the 
future. The species is considered abundant within its habitat, which 
consists of adequate area and quality to maintain survival and 
reproduction in spite of disturbances. Thus, the Monito gecko appears 
to have highly resilient population attributes (e.g., habitat 
generalist, potential high adult survival rate) that allow at least 
some degree of disturbance within a harsh xeric environment.
    For the Monito gecko, we determined that a foreseeable future of 20 
to 30 years is reasonable. Based on the available information, making 
threat projections beyond this time frame increases speculation. For 
example, although rats could potentially reinvade Monito Island, the 
probability of rats reinvading is considered low since rats have not 
been detected after the eradication effort was completed in 1999. In 
addition, lifespan data for almost all of the Sphaerodactylus species 
is not available. One species from Martinique in the West Indies, 
Sphaerodactylus vicenti ronaldi, estimated longevity did not exceed 4 
years (Leclair and Leclair 2011). Assuming the Monito gecko would have 
a similar lifespan, a foreseeable future of 20 to 30 years would allow 
for multiple generations and detection of any population changes. The 
Monito gecko has been listed since 1982, has persisted apparent mayor 
threats (i.e. bombing effects, rat predation), and is currently well 
represented. Further, we do not anticipate significant impacts in the 
foreseeable future from climate change factors. Therefore, without no 
immediate risk of extinction, we have a baseline to continue assessing 
how the Monito gecko population may respond in the foreseeable future.
    We carefully assessed the best scientific and commercial 
information available regarding the threats faced by the Monito gecko 
in developing the proposed rule and this final rule. The Service finds 
that the present or threatened destruction, modification, or 
curtailment of its habitat (factor A) is not a threat to the continued 
existence of the Monito gecko, and we do not expect it to be a threat 
in the future. We also conclude that overutilization (factor B) and 
disease (factor C) are not a threat to the Monito gecko. Natural 
predation by other native lizards may occur, but this activity is 
considered a low-magnitude threat because the Monito gecko has 
persisted despite potential predation and there is no indication that 
the magnitude of an undetermined natural predation pressure 
significantly affects the gecko's survival. No rats have been detected 
on Monito Island since August 1999. Therefore, we conclude that 
predation (factor C) is no longer a threat to the Monito gecko.
    The species' apparent small population size (factor E), noted at 
the time of listing, may have been an artifact of bias as surveys were 
conducted under conditions when the species was not easily detectable. 
There are no known potential climate change effects (i.e., sea level 
rise or changes in air temperature) (factor A) that negatively affect 
the Monito gecko. No other natural or manmade factors are considered 
threats (factor E). The Monito gecko and its habitat have been and will 
continue to be protected under Commonwealth laws and regulations 
(factor D), and these existing regulatory mechanisms are adequate to 
protect the Monito gecko now and in the future. The information 
indicates that this species is no longer at risk of extinction, nor is 
it likely to experience reemergence of threats and associated 
population declines in the foreseeable future. Based on the analysis 
above and after considering the best available scientific and 
commercial information, we conclude that the Monito gecko does not 
currently meet the Act's definition of either an endangered or 
threatened species throughout all or a significant portion of its 
range.

Effects of This Rule

    This final rule revises 50 CFR 17.11(h) to remove the Monito gecko 
from the Federal List of Endangered and Threatened Wildlife. The 
prohibitions and conservation measures provided by the Act would no 
longer apply to the Monito gecko. Federal agencies will no longer be 
required to consult with us under section 7 of the Act to ensure that 
any action authorized, funded, or carried out by them is not likely to 
jeopardize the gecko's continued existence. The prohibitions under 
section 9(a)(1) of the Act will no longer make it illegal for any 
person subject to the jurisdiction of the United States to import or 
export, transport in interstate or foreign commerce, or take, possess, 
sell, deliver, carry, transport, or ship Monito geckos. Finally, this 
rule will also remove the Federal regulations related to the Monito 
gecko listing: The critical habitat designation at 50 CFR 17.95(c).

Post-Delisting Monitoring

    Section 4(g)(1) of the Act requires us to implement a system in 
cooperation with the States to monitor effectively for not less than 5 
years the status of all species that are delisted due to recovery. 
Post-delisting monitoring (PDM) refers to activities undertaken to 
verify that a species delisted due to recovery remains secure from the 
risk of extinction after the protections of the Act no longer apply. 
The primary goal of PDM is to ensure that the species' status does not 
deteriorate, and if a decline is detected, to take measures to halt the 
decline so that proposing it as threatened or endangered is not again 
needed. If at any time during the PDM period, data indicate that 
protective status under the Act should be reinstated, we can initiate 
listing procedures, including, if appropriate, emergency listing. At 
the conclusion of the PDM period, we will review all available 
information to determine if re-listing, the continuation of monitoring, 
or the termination of monitoring is appropriate.
    Section 4(g) of the Act explicitly requires cooperation with the 
States (which includes Territories such as Puerto Rico) in development 
and implementation of PDM programs. However, we remain responsible for 
compliance with section 4(g) and, therefore, must remain actively 
engaged in all phases of PDM. We also seek active participation of 
other entities that are expected to assume responsibilities for the 
species' conservation after delisting. In April 2017, the PRDNER and 
the Service agreed to be cooperators in the PDM for the Monito gecko.

[[Page 52800]]

    We have prepared a PDM Plan for the Monito gecko (USFWS 2017). The 
plan is designed to detect significant declines in the Monito gecko 
with reasonable certainty and precision, and detect possible new or 
reoccurring threats (i.e., presence of rats). The plan:
    (1) Summarizes the species' status at the time of delisting;
    (2) Defines thresholds or triggers for potential monitoring 
outcomes and conclusions;
    (3) Lays out frequency and duration of monitoring;
    (4) Articulates monitoring methods including sampling 
considerations;
    (5) Outlines data compilation and reporting procedures and 
responsibilities; and
    (6) Proposes a PDM implementation schedule including timing and 
responsible parties.
    It is our intent to work with our partners towards maintaining the 
recovered status of the Monito gecko.

Required Determinations

National Environmental Policy Act

    We have determined that we do not need to prepare an Environmental 
Assessment or Environmental Impact Statement, as defined in the 
National Environmental Policy Act of 1969 (42 U.S.C. 4321 et seq.), in 
connection with regulations adopted pursuant to section 4(a) of the 
Endangered Species Act. We published a notice outlining our reasons for 
this determination in the Federal Register on October 25, 1983 (48 FR 
49244).

Government-to-Government Relationship With Tribes

    In accordance with the President's memorandum of April 29, 1994, 
``Government-to-Government Relations with Native American Tribal 
Governments'' (59 FR 22951), Executive Order 13175, and the Department 
of the Interior's manual at 512 DM 2, we readily acknowledge our 
responsibility to communicate meaningfully with recognized Federal 
Tribes on a government-to-government basis. We have determined that no 
tribal lands are affected by this proposal.

References Cited

    A complete list of references cited is available on https://www.regulations.gov under Docket Number FWS-R4-ES-2017-0082.

Author

    The primary authors of this document 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, Reporting and 
recordkeeping requirements, Transportation.

Regulation Promulgation

    Accordingly, we amend part 17, subchapter B of chapter I, title 50 
of the Code of Federal Regulations, as 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.


Sec.  17.11   [Amended]

0
2. Amend Sec.  17.11(h) by removing the entry ``Gecko, Monito'' under 
``Reptiles'' from the List of Endangered and Threatened Wildlife.


Sec.  17.95   [Amended]

0
3. Amend Sec.  17.95(c) by removing the entry for ``Monito Gecko 
(Sphaerodactylus micropithecus)''.

    Dated: August 9, 2019.
Margaret E. Everson,
Principal Deputy Director, U.S. Fish and Wildlife Service, Exercising 
the Authority of the Director, U.S. Fish and Wildlife Service.
[FR Doc. 2019-20907 Filed 10-2-19; 8:45 am]
 BILLING CODE 4333-15-P