State of California et al v. Trump et al

Filing 89

OPPOSITION/RESPONSE (re 59 MOTION for Preliminary Injunction ) filed by Department of Defense, David Bernhardt, Mark T. Esper, Steven T. Mnuchin, Kirstjen M. Nielsen, Patrick M. Shanahan, Richard V. Spencer, Donald J. Trump, U.S. Department of Homeland Security, U.S. Department of the Interior, U.S. Department of the Treasury, United States of America, Heather Wilson. (Attachments: # 1 Exhibit, # 2 Exhibit, # 3 Exhibit, # 4 Exhibit, # 5 Exhibit, # 6 Exhibit, # 7 Exhibit, # 8 Exhibit, # 9 Exhibit, # 10 Exhibit, # 11 Exhibit, # 12 Exhibit, # 13 Exhibit, # 14 Exhibit)(Warden, Andrew) (Filed on 4/25/2019)

EXHIBIT 13

U.S. Fish & Wildlife Service

Mexican Wolf
Recovery Plan
First Revision

November 2017

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MEXICAN WOLF RECOVERY PLAN, FIRST REVISION

NOVEMBER 2017

DISCLAIMER
The Endangered Species Act of 1973 (ESA), as amended (16 U.S.C. 1531 et seq.), requires the
development of recovery plans for listed species, unless such a plan would not promote the
conservation of a particular species. In accordance with section 4(f)(1) of the ESA and to the
maximum extent practicable, recovery plans delineate actions which the best available science
indicates are required to recover and protect listed species. Plans are published by the U.S. Fish
and Wildlife Service (Service), and are sometimes prepared with the assistance of recovery
teams, contractors, state agencies, and others. Recovery teams serve as independent advisors to
the Service. Plans are reviewed by the public and submitted to additional peer review before
they are adopted by the Service. The purpose of a recovery plan is to provide a scientifically
based, logical, and effective roadmap for the recovery of a species. It explains what is needed
for species recovery and how to get there. Recovery plans are advisory documents, not
regulatory documents. A recovery plan does not commit any entity to implement the
recommended strategies or actions contained within it for a particular species, but rather provides
guidance for ameliorating threats and implementing proactive conservation measures, as well as
providing context for implementation of other sections of the Endangered Species Act, such as
section 7(a)(2) consultations on Federal agency activities, development of Habitat Conservation
Plans, or the creation of experimental populations under section 10(j). The recovery plan
objectives will be attained and any necessary funds made available subject to budgetary and
other constraints affecting the parties involved, as well as the need to address other priorities.
Nothing in this plan should be construed as a commitment or requirement that any Federal
agency obligate or pay funds in contravention of the Anti-Deficiency Act, 31 U.S.C. 1341, or
any other law or regulation. Recovery plans do not necessarily represent the views or the official
positions or approval of any individuals or agencies involved in the plan formulation, other than
the Service. They represent the official position of the Service once they have been signed by
the Regional Director. Approved recovery plans are subject to modification as dictated by new
information, changes in species status, and the completion of recovery actions. Please check for
updates or revisions at the website below before using.
We developed the Mexican Wolf Recovery Plan, First Revision, using a revised recovery
planning process called Recovery Planning and Implementation (RPI), adopted by the Service in
2016. RPI is intended to reduce the time needed to develop recovery plans, increase the
relevancy of recovery plans over a longer timeframe, and add flexibility to recovery plans so
they can be adjusted to new information or circumstances. Under RPI, a recovery plan includes
statutorily required elements (objective, measurable criteria; site-specific management actions;
and estimates of time and costs), along with a concise introduction and explanation of our
strategy to achieve species recovery. The RPI recovery plan is supported by a separate Species
Status Assessment, or in some cases, such as with the Mexican wolf, a species Biological Report,
which provides background, life-history, and threat assessment information. The biological report
for the Mexican wolf is posted on our website https://www.fws.gov/southwest/es/mexicanwolf/.
Additionally under RPI, we develop a separate working document called the Recovery
Implementation Strategy (implementation strategy). The implementation strategy steps down
from the more general description of actions described in the recovery plan to detail the nearterm, specific activities needed to implement the recovery plan. The implementation strategy,
which is also posted on our website, will be adaptable by incorporating new information as
needed without revising the recovery plan, unless we need to change statutory elements.
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ACKNOWLEDGEMENTS
A revision of the 1982 Mexican Wolf Recovery Plan has been a long time in coming, and we are
grateful to the many people who have contributed their expertise, perspectives, and dedication to
the Mexican wolf recovery effort over the last four decades. In particular, we would like to
express our gratitude to our interagency and tribal partners and their staff; previous recovery
team members and participants in recent recovery planning workshops; colleagues in Mexico;
members of the Mexican Wolf Tribal Working Group; Species Survival Plan institutions,
facilities, and staff; Service leaders and staff; the local communities in the Mexican wolf
recovery area in the United States; and the general public. We have included a more extensive
list of Acknowledgments in the Biological Report.

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LITERATURE CITATION AND AVAILABILITY
Literature citation should read as follows:
U.S. Fish and Wildlife Service. 2017. Mexican Wolf Recovery Plan, First Revision. Region 2,
Albuquerque, New Mexico, USA.
Copies of the document can be requested from:
U.S. Fish and Wildlife Service
New Mexico Ecological Services Field Office
2105 Osuna Drive NE
Albuquerque, New Mexico 87113
Telephone #: [phone] or 1-800-299-0196
U.S. Fish and Wildlife Service
Southwest Regional Office
P.O. Box 1306
Albuquerque, New Mexico 87103-1306
Telephone #: [phone]
Copies are also available online at:
http://www.fws.gov/southwest/es/mexicanwolf

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TABLE OF CONTENTS
DISCLAIMER ............................................................................................................................................... i
ACKNOWLEDGEMENTS .......................................................................................................................... ii
LITERATURE CITATION AND AVAILABILITY .................................................................................. iii
TABLE OF CONTENTS ............................................................................................................................. iv
LIST OF FIGURES ...................................................................................................................................... v
LIST OF TABLES ........................................................................................................................................ v
EXECUTIVE SUMMARY .................................................................................................................... ES-1
I.

INTRODUCTION AND BACKGROUND ......................................................................................... 1
Recovery Planning .................................................................................................................................... 1
Recovery Implementation in the United States and Mexico ..................................................................... 4

II.

THREATS TO THE MEXICAN WOLF ............................................................................................. 9

III. RECOVERY STRATEGY ................................................................................................................. 10
Geographic Distribution.......................................................................................................................... 11
Population Abundance ............................................................................................................................ 13
Genetic Management .............................................................................................................................. 13
Monitoring and Adaptive Management .................................................................................................. 15
Collaborative Recovery Implementation ................................................................................................ 16
IV. RECOVERY GOAL, OBJECTIVES, AND CRITERIA ................................................................... 18
Downlisting Recovery Criteria ............................................................................................................... 18
Delisting Recovery Criteria .................................................................................................................... 19
Rationale for Recovery Criteria .............................................................................................................. 20
Resiliency............................................................................................................................................ 20
Representation..................................................................................................................................... 22
Redundancy......................................................................................................................................... 24
The Need for Regulatory Protection ....................................................................................................... 24
Explanation of Downlisting Criteria ....................................................................................................... 25
V.

EVALUATION OF THE RECOVERY STRATEGY AND PROGRESS TOWARD RECOVERY 26

VI. ACTIONS NEEDED .......................................................................................................................... 28
Estimated Cost and Timing of Recovery ................................................................................................ 28
Acronyms Used In Recovery Action Table ............................................................................................ 29
VII. LITERATURE CITED ....................................................................................................................... 35

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LIST OF FIGURES
Figure 1. Mexican Wolf Experimental Population Area in Arizona and New Mexico, United
States (80 FR 2512, January 16, 2015). .......................................................................................... 6
Figure 2. Annual Minimum Population Count of Mexican Wolves in the MWEPA, 1998-2016
(U.S. Fish and Wildlife Service files). ............................................................................................ 7
Figure 3. Focal areas for Mexican wolf recovery in the United States and Mexico. (Habitat
quality from Martínez-Meyer et al. 2017, titled “Figure 22. Rescaled intermediate habitat
suitability scenario for the Mexican wolf based on the combination of climatic suitability, land
cover use, human population density, road density, and UBI.”) .................................................. 12

LIST OF TABLES
Table 1. Recovery Action Table: Estimated Cost, Time, and Priority for Recovery Actions for
the Mexican Wolf ......................................................................................................................... 31

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EXECUTIVE SUMMARY
The Mexican wolf (Canis lupus baileyi) has been protected as an endangered subspecies of gray
wolf since 1976 under the Endangered Species Act (ESA) of 1973, as amended (80 FR 2488).
Following the near extinction of the Mexican wolf due to predator eradication efforts in the mid
to late 1800s to mid-1900s, the U.S. Fish and Wildlife Service (Service, we), Mexico, and
partner agencies initiated a binational captive breeding program descended from 7 founder
wolves and began efforts to re-establish Mexican wolves in the wild in the United States in 1998
and Mexico in 2011.
Our recovery strategy for the Mexican wolf is to establish and maintain a minimum of two
resilient, genetically diverse Mexican wolf populations distributed across ecologically and
geographically diverse areas in the subspecies’ range in the United States and Mexico. The
recovery strategy for the Mexican wolf addresses the threats of human-caused mortality,
extinction risk associated with small population size, and loss of gene diversity. Moreover, it
ensures that Mexican wolf populations can achieve the resiliency, representation, and
redundancy needed to downlist and delist the Mexican wolf, as described in the Rationale for
Recovery Criteria. At the time of recovery, we expect Mexican wolf populations to be stable or
increasing in abundance, well-distributed geographically within their range, and genetically
diverse. The recovery strategy’s primary components include expanding the geographic
distribution of the Mexican wolf, increasing population abundance, improving gene diversity,
monitoring wild populations and implementing adaptive management, and collaborating with
partners to address social and economic concerns related to Mexican wolf recovery. We
developed this binational Mexican wolf recovery strategy in coordination with federal agencies
in Mexico and state, federal, and Tribal agencies in the United States.
Our recovery goal is to conserve and protect the Mexican wolf and its habitat so that its longterm survival is secured, populations are capable of enduring threats, and it can be removed from
the list of threatened and endangered species. Recovery objectives for the Mexican wolf are:
1.
2.
3.
4.

Increase the size of two Mexican wolf populations;
Improve gene diversity and maintain the health of Mexican wolves;
Ensure adequate habitat availability to support viable Mexican wolf populations;
Maintain the Mexican Wolf Species Survival Plan (SSP) captive breeding program to
improve the status of wild populations;
5. Promote Mexican wolf conservation through education and outreach programs; and
6. Ensure recovery success.
Downlisting Recovery Criteria
Option 1:
The Mexican wolf will be considered for downlisting when:
a) The United States population average over a 4-year period is greater than or equal to 320
Mexican wolves; and

Executive Summary

ES-1

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b) Gene diversity available from the captive population has been incorporated in the United
States population through the scheduled releases of wolves surviving to breeding age as
identified in delisting criteria.
-orOption 2:
The Mexican wolf will be considered for downlisting when a minimum of two populations (one
in the United States and one in Mexico) meet abundance and genetic criteria as follows:
a) Each population average over the same 4-year period is greater than or equal to 150
wolves with an annual positive population growth rate; and
b) Gene diversity available from the captive population has been incorporated into both the
United States and Mexico populations through the scheduled releases of wolves surviving
to breeding age as identified in delisting criteria.
Delisting Recovery Criteria
The Mexican wolf will be considered for delisting when:
1) A minimum of two populations meet all abundance and genetic criteria as follows:
United States
a) The population average over an 8-year period is greater than or equal to 320 wolves (e.g.,
annual wolf abundance of 200, 240, 288, 344, 412, 380, 355, and 342 averages 320
wolves);
b) The population must exceed 320 wolves each of the last 3 years of the 8- year period;
c) The annual population growth rate averaged over the 8-year period is stable or increasing
(e.g., annual averages of 1.2, 1.2, 1.2, 1.2, 1.2, 0.9, 0.9, and 1.0 averages 1.1); and
d) Gene diversity available from the captive population has been incorporated into the
United States population through scheduled releases of a sufficient number of wolves to
result in 22 released Mexican wolves surviving to breeding age in the United States
population. “Surviving to breeding age” means a pup that lives two years to the age of
breeding or an adult or subadult that lives for a year following its release. “Scheduled
releases” means captive releases and translocations that achieve genetic representation, as
described in Rationale for Recovery Criteria.
Mexico
a) The population average over an 8-year period is greater than or equal to 200 wolves;
b) The population must exceed 200 wolves each of the last three years of the 8- year period;
c) The annual population growth rate averaged over the 8-year period is stable or
increasing; and
d) Gene diversity available from the captive population has been incorporated into the
Mexico population through scheduled releases of a sufficient number of wolves that

Executive Summary

ES-2

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results in 37 released Mexican wolves surviving to breeding age in the Mexico
population. “Surviving to breeding age” means a pup that lives 2 years to the age of
breeding or an adult or subadult that lives for a year following its release. “Scheduled
releases” means captive releases and translocations that achieve genetic representation, as
described in Rationale for Recovery Criteria.
-and2) States and Tribes will ensure regulatory mechanisms are in place to prohibit or regulate
human-caused mortality of Mexican wolves in those areas necessary for recovery such that
the Service determines at least 320 Mexican wolves are likely to be maintained in the United
States in the absence of Federal ESA protections. In addition, Mexico will ensure regulatory
mechanisms are in place to protect Mexican wolves from human-caused mortality, such that
the Service determines at least 200 Mexican wolves are likely to be maintained in Mexico.
To ensure we are making expeditious progress toward recovery, we will evaluate our progress at
5 and 10 years after implementation of the recovery plan and subsequently adjust our
management as needed. In addition, we will conduct 5-year species status reviews required
under the Section 4(c)(2) of the ESA.
We developed recovery actions for the Mexican wolf for each objective, which include:
surveying and monitoring Mexican wolf populations in the wild; conducting releases (including
cross-fostering) and translocations of Mexican wolves; reducing human-caused mortality of
Mexican wolves; reducing Mexican wolf-livestock conflicts; developing and implementing plans
for releases, cross-fostering, and translocations; monitoring and managing Mexican wolf health
and genetic health; maintaining habitat; maintaining and enhancing connectivity within and
between Mexican wolf populations; maintaining and improving the status of native prey
populations; managing the Mexican wolf captive breeding population; conducting education and
outreach; managing the recovery program; coordinating binational recovery efforts; and
developing adequate regulations and management and monitoring plans to maintain viable
Mexican wolf populations after delisting.
We expect to recover the Mexican wolf within 25-35 years. The total estimated cost of
implementing this plan through year 2043, the estimated recovery date of the Mexican wolf, is
$178,439,000. The estimated cost to implement the first 5 years of recovery actions (i.e.,
intermediate steps toward the goal of recovery) is $38,455,000. This cost includes those borne
by governmental agencies and nongovernmental organizations in the United States and Mexico.

Executive Summary

ES-3

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I.

NOVEMBER 2017

INTRODUCTION AND BACKGROUND

The Mexican wolf, Canis lupus baileyi, has been protected as an endangered subspecies of gray
wolf since 1976 under the Endangered Species Act (ESA) of 1973, as amended (80 FR 2488).
The Mexican wolf is a top predator native to the southwestern United States and Mexico that
lives in packs and requires large amounts of forested terrain with adequate ungulate (deer and
elk) populations to support the pack. Predator eradication programs in the mid to late 1800s to
mid-1900s resulted in the near extinction of the Mexican wolf. Extinction was averted with the
initiation of a binational captive breeding population descended from seven Mexican wolf
founders.
The United States Fish and Wildlife Service (Service, we) has been engaged in efforts to
conserve and ensure the survival of the Mexican wolf for over three decades. Today, Mexican
wolves again inhabit portions of the southwestern United States in Arizona and New Mexico,
and the northern Sierra Madre Occidental of Chihuahua and Sonora in Mexico. Mexican wolves
are present in these areas due to ongoing reintroduction efforts in both countries, supported by
the binational captive breeding program. Additional information about the Mexican wolf
reintroduction effort is available in the Biological Report for the Mexican Wolf (USFWS 2017a),
and the following documents:
•

Final Environmental Impact Statement for the Proposed Revision to the Regulations for the
Nonessential Experimental Population of the Mexican wolf (Canis lupus baileyi) (USFWS
2014).

•

Record of Decision (ROD) for the Proposed Revision to the Regulations for the Nonessential
Experimental Population of the Mexican wolf (Canis lupus baileyi) (USFWS 2015).

•

Revision to the Regulations for the Nonessential Experimental Population of the Mexican
Wolf (80 FR 2512).

•

Endangered and Threatened Wildlife and Plants; Endangered Status for the Mexican Wolf
(80 FR 2488).
All documents are available on online: https://www.fws.gov/southwest/es/mexicanwolf/documents.cfm.
Recovery Planning
Three other recovery plans have been finalized for the Mexican wolf in the United States and
Mexico:
•

Mexican Wolf Recovery Plan, 1982 (USFWS 1982),

•

Proyecto de Recuperación del Lobo Mexicano (PREP) (SEMARNAP 2000), and

•

Programa de Acción para la Conservación de la Especie: Lobo Gris Mexicano (PACE)
(CONANP 2009).

The 1982 Mexican Wolf Recovery Plan was written by a recovery team established by the
Service and signed by the Service and the Dirección General de la Fauna Silvestre in Mexico.
The latter two plans were written under the guidance of the responsible federal agency in Mexico
at the time (Secretaría de Medio Ambiente, Recursos Naturales y Pesca [SEMARNAP] and

Introduction and Background

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Comisión Nacional de Áreas Naturales Protegidas [CONANP]), in collaboration with the
National Technical Advisory Subcommittee for the Recovery of the Mexican Wolf in Mexico.
All three plans acknowledge the binational historical range of the Mexican wolf in the United
States and Mexico, but each plan was written within the context of the federal laws governing its
content. The 1982 Mexican Wolf Recovery Plan was written pursuant to the Service’s
obligation to develop recovery plans for species protected by the ESA, whereas the 2000
Proyecto de Recuperación was written pursuant to Mexico’s Ley General del Equilibrio
Ecológico y la Protección al Ambiente (or General Law for Ecological Balance and
Environmental Protection) and the 2009 Programa de Acción was written pursuant to Mexico’s
Ley General de Vida Silvestre (or General Wildlife Law).
Mexico: Mexico’s Proyecto de Recuperación was not required by law to set a numeric goal for
recovery. The plan did, however, establish an objective to reach population levels that would
ensure long-term viability by reintroducing Mexican wolves into several areas in Mexico
(SEMARNAP 2000). The document explained that Mexico supported reintroduction on both
sides of the Mexico-United States border and stated that it would be difficult to find appropriate
habitat for reintroduction in Mexico. The Proyecto de Recuperación suggested that the best
habitat may exist within the Sierra Madre Occidental and the Sierra Madre Oriental mountain
ranges (SEMARNAP 2000).
The responsibilities for Mexico’s priority species were transferred to CONANP in 2004, and the
Programa de Acción was finalized in 2009 with the participation of the former technical advisory
subcommittee. (The rule that established the National Technical Advisory Committee for
Priority Species was abolished in March 2009, therefore, the subcommittee ceased to exist
formally). This action plan established the necessary steps to begin the reintroduction of the
Mexican wolf in Mexico, with five strategic goals: define at least six potential sites for Mexican
wolf reintroduction; strengthen law enforcement actions to protect habitat within the historical
range of the species; involve a variety of sectors of society in the recovery of the species; support
the subcommittee’s efforts for the reintroduction of the wolf; and create the conditions to allow
the strategies of the subcommittee to contribute to the goals of the PACE (CONANP 2009). The
action plan is considered to be outdated and in need of revision, but revision of these actions
plans are not mandated on a specific schedule.
United States: The Service’s 1982 Mexican Wolf Recovery Plan did not contain all three of the
recovery plan elements specified in section 4(f)(1) of the ESA. At the time of writing, the
recovery team could not foresee full recovery and eventual delisting of the Mexican wolf due to
its dire status in the wild and their assessment of a lack of suitable habitat within historical range
due to human activities. Therefore, the recovery team stopped short of providing the objective
and measurable recovery criteria required by the ESA and instead laid out a “prime objective”:
“To conserve and ensure the survival of Canis lupus baileyi by maintaining a captive
breeding program and re-establishing a viable, self-sustaining population of at least 100
Mexican wolves in the middle to high elevations of a 5,000-square-mile area within the
Mexican wolf’s historic range (USFWS 1982:23).”

Introduction and Background

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The recovery actions and time and cost estimates in the 1982 Recovery Plan focused on
information gathering and management recommendations in support of this prime objective.
The Service initiated revisions of the 1982 Mexican Wolf Recovery Plan in the mid-1990s and
early 2000s, but these revisions were not finalized due to many issues, including litigation related
to gray wolf reclassifications (USFWS 2010). These efforts to revise the recovery plan focused
on varying recovery areas. The 2003 effort focused on the southwestern distinct population
segment (DPS) of the gray wolf (68 FR 15803); this DPS extended from Mexico to Interstate 70
in Colorado and Utah. A court vacated the rule that included the southwestern DPS designation,
which halted this recovery planning effort (Defenders of Wildlife; et al., v. Secretary, United
States Department of the Interior; et al., 354 F.Supp.2d 1156 (D. Or.2005).
We reinitiated recovery planning for the Mexican wolf again in 2010. This recovery planning
effort was put on hold in 2013 while the Service focused on listing the Mexican wolf as an
endangered subspecies and on developing revised regulations for the management of the
experimental population of Mexican wolves within the Mexican Wolf Experimental Population
Area (MWEPA). On June 13, 2013, the Service concurrently proposed a rule in the Federal
Register to remove the gray wolf (Canis lupus) from the Federal List of Threatened and
Endangered Species and list the Mexican wolf (Canis lupus baileyi) subspecies as endangered
and expand recovery efforts in the Southwest (78 FR 35664). On January 16, 2015, the Service
finalized a rule listing Mexican wolves as an endangered species, separate from the gray wolf (80
FR 2488) and revised the regulations for the nonessential experimental population of the
Mexican wolf under section 10(j) of the ESA to improve the population’s ability to contribute to
recovery (80 FR 2512).
With the encouragement of the States and based on our collaborative relationship with Mexico,
we reinitiated recovery planning in December 2015, focusing south of Interstate 40 in Arizona
and New Mexico and into Mexico, which encompasses the historical range of the Mexican wolf
(Parsons 1996). The Service convened six recovery planning workshops to review biological
information that would inform the development of the recovery plan. The workshops were
attended by staff from the states of Arizona, New Mexico, Colorado, and Utah; the U.S. Forest
Service; and the Mexican government. In addition, the Service extended invitations to
participate in these workshops to the scientists with experience related to wolf research that were
on the Science and Planning Subgroup of the 2010 Mexican Wolf Recovery Team and to
scientists who were recommended by the states and Mexico. The IUCN Conservation Planning
Species Group facilitated the workshops and developed the Vortex Population Viability Analysis
model. We also coordinated with Tribes and Pueblos on the development of this recovery plan
through the Mexican Wolf Tribal Working Group. This group developed a Tribal Perspectives
on Mexican Wolf Recovery report (Mexican Wolf Tribal Working-Group 2017) that can be found
online at https://www.fws.gov/southwest/es/mexicanwolf/MWRP.cfm.
In these workshops, participants reviewed the input parameters in the Vortex model, which
helped inform the development of recovery criteria regarding the number of wolves, the number
and genetic composition of populations, and connectivity needed to achieve recovery.
Participants in the workshop modelled the amount of suitable habitat and prey available from the
general vicinity of Interstate 40 south into the Sierra Madre Occidental and Sierra Madre
Oriental in Mexico to determine where on the landscape Mexican wolf populations could be

Introduction and Background

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established and sustained. Based on these analyses, the Service and Mexico determined that
there was sufficient habitat to allow for Mexican wolf recovery. However, due to uncertainty in
achieving recovery, we included a periodic review process in the recovery plan to determine the
effectiveness of Mexican wolf recovery efforts. If we are not achieving the expected level of
recovery, we will revisit the recovery strategy and work with States and others to identify other
areas with suitable habitat and adequate prey to achieve recovery; change techniques used to
address gene diversity; or implement other substantive changes.
2017 Mexican Wolf Recovery Plan, First Revision: The 2017 binational Mexican Wolf
Recovery Plan, First Revision replaces and supersedes the Service’s 1982 Mexican Wolf
Recovery Plan, but it does not replace, supersede, or otherwise affect Mexico’s Proyecto de
Recuperación and Programa de Acción. The Service recognizes that the objectives of the 1982
Mexican Wolf Recovery Plan were largely to halt extinction and explore whether Mexican
wolves could be reestablished in the wild. Together with our partners, we have achieved those
objectives. The Mexican Wolf Recovery Plan, First Revision provides a strategy, criteria, and
actions to fully recover the Mexican wolf pursuant to the ESA and contains the required recovery
plan elements specified by the ESA (section 4(f)(1)):
i. a description of such site-specific management actions as may be necessary to achieve
the plan’s goal for the conservation and survival of the species;
ii. objective, measurable criteria which, when met, would result in a determination, in
accordance with the provisions of this section, that the species be removed from the list;
and
iii. estimates of the time required and the cost to carry out those measures needed to achieve
the plan’s goal and to achieve intermediate steps toward that goal.
We developed this recovery plan using Mexican wolf monitoring data from the wild and
captivity, data from other gray wolf populations when relevant, and other relevant scientific
information. We also utilized two recent computer modeling analyses to develop the recovery
strategy and criteria in this recovery plan. The first model analyzed population viability
(referenced herein as population viability analysis or PVA [Miller 2017]). It used subspeciesspecific data (e.g., pairing rates, survival rates, and models for number of detectable pups, and
probability of producing a litter), some of which were not available for previous model
evaluations (Carroll et al. 2014) to predict how a population will perform over time under
different scenarios. The second model analyzed habitat suitability (referred to as habitat
suitability analysis [Martínez-Meyer et al. 2017]). It used Geographic Information System data
layers to identify variations in habitat quality across the landscape. These data and analyses are
provided in our Biological Report for the Mexican Wolf (referenced herein as the Biological
Report [USFWS 2017a]). We will update the Biological Report as needed to maintain a
compendium of the available scientific information upon which to base collaborative recovery
efforts for the Mexican wolf (see Disclaimer for additional explanation of the Service’s new
Recovery Planning and Implementation process).
Recovery Implementation in the United States and Mexico
Recovery efforts for the Mexican wolf have been underway in the United States and Mexico for
several decades. Working together, both countries are focused on maintaining the binational
Introduction and Background

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captive population of Mexican wolves and on re-establishing wild populations by releasing
captive wolves into reintroduction areas and subsequently promoting natural growth of the
populations.
Captive Breeding Program: The Mexican wolf captive breeding program was established in
1977 to 1980 with three effective founder wolves captured from the wild in Mexico. These
founding wolves and their offspring were initially referred to as the Certified lineage, later
renamed the McBride lineage (Parsons 1996). The captive breeding program has been managed
pursuant to breeding protocols and genetic and demographic goals established by the Association
of Zoos and Aquariums’ Species Survival Plan since 1994 (Hedrick et al. 1997). Two additional
lineages of Mexican wolves, the Ghost Ranch lineage, founded by two unrelated wolves, and the
Aragon line, founded by two unrelated wolves, were maintained in captivity since the 1960s and
1970s, but were managed apart from the McBride lineage because of uncertainties about their
origins. Through genetic analysis, the Ghost Ranch and Aragon lineages were confirmed to be
pure Mexican wolves, and in 1995 they were integrated into the captive breeding program due to
the limited genetic diversity of the captive population and the potential for inbreeding depression
to hinder its success (Parsons 1996, Hedrick et al. 1997). The combination of the three lineages
increased the founding base of the captive population from three to seven pure Mexican wolves
(Hedrick et al. 1997).
Today, the binational captive breeding program continues to play a vital role in the conservation
of the Mexican wolf by providing healthy wolves for release to the wild. However, the small
number of founders of the captive population and the resultant low gene diversity available have
been a concern since the beginning of the recovery program (Hedrick et al. 1997) and remain a
concern today (Siminski and Spevak 2017, and see USFWS 2017a). Long-term viability or
adaptive potential depends on the store of genetic variability. It is desirable to retain as much
genetic variability as possible, and it is uncertain when loss of genetic variability might manifest
in compromised reproductive function or physical and physiological abnormality (Soulé et al.
1986). As of July 2017, the binational captive program houses 281 wolves in 55 institutions, and
has retained approximately 83% of the gene diversity of the founders, which is lower than the
recommended retention of 90% for most captive breeding programs (Siminski and Spevak 2017,
Soulé et al. 1986). It is expected that even with optimal management, the gene diversity in the
captive population will continue to decline over time as wolves die or reach reproductive
senescence. In its current condition, the population would be expected to retain 75% gene
diversity over 67 years and 73% in 100 years (Siminski and Spevak 2017). The gene diversity of
the captive population is higher than either wild population in the United States or Mexico. This
is expected, as the wild populations are established utilizing animals that are genetically well
represented within the captive population (Siminski and Spevak 2017) and because we are able
to manage which wolves are paired each year for breeding in captivity, but it is more difficult to
do so in the wild.
The United States and Mexico have each undertaken efforts to establish the Mexican wolf in the
wild by releasing captive-bred wolves into areas of suitable habitat in each country. The United
States and Mexico communicate their reintroduction plans with one another, share equipment,
and transfer information and technology through staff visits to each country. Implementation of

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reintroductions occurs according to the legal frameworks and management provisions for each
country.
United States Reintroductions: We began releasing Mexican wolves back into the wild in
Arizona and New Mexico in 1998 in the MWEPA (USFWS 1998, 63 FR 1752). We revised this
experimental population area in 2015 (Figure 1; 80 FR 2512). We, with our interagency
partners, continue to manage Mexican wolves in this area pursuant to regulations under section
10(j) of the ESA that provide management flexibility and aid in the conservation and recovery of
the Mexican wolf.

Figure 1. Mexican Wolf Experimental Population Area in Arizona and New Mexico, United States (80
FR 2512, January 16, 2015).

The Mexican wolf population in the United States has exhibited robust growth since 2009
(Figure 2). As of December 31, 2016, a population of at least 113 wild Mexican wolves inhabits
the United States, the largest population size reached to date (USFWS 2017b). In 2016, all
Mexican wolves in the United States were wild-born, with the exception of surviving crossfostered pups from captivity (at least two surviving pups have been documented as of November
2017), demonstrating that population growth is driven by natural reproduction rather than the
release of wolves from captivity. We conducted fourteen releases of wolves from captivity,
including 10 cross-fostered pups, between 2009 and 2017, during which time the population

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grew from a minimum population count of 42 to 113 wolves. We have documented wild-born
wolves breeding and raising pups in the wild for 16 consecutive years.
120

Annual Minimum Population of Mexican Wolves in MWEPA

No. of Wolves

100
80
60
40
20
0

1998 2000 2002 2004 2006 2008 2010 2012 2014 2016
Year
Minimum Population Count

Reproduction

Pups Alive Dec. 31

Figure 2. Annual Minimum Population Count of Mexican Wolves in the MWEPA, 1998-2016 (U.S. Fish
and Wildlife Service files).

Although the population has been increasing since 2009, we consider Mexican wolves in the
United States to be too closely related to one another (referred to as high mean kinship) to ensure
the population will be robust over time. Mean kinship for the United States population is 0.2452
(Siminski and Spevak 2017). The high relatedness of wolves to one another and ongoing loss of
gene diversity increases concerns over the potential for inbreeding depression to have negative
impacts on future population growth in the United States (USFWS 2017a). Due to these
concerns, the recovery plan focuses on inserting gene diversity into the United States population
through the release of wolves from the captive population. Additionally, genetic diversity is
required for populations to adapt to environmental change. We have documented that inbreeding
depression is impacting the probability of a breeding pair producing a litter, but not to a degree
that is hindering annual population growth in the United States population (USFWS 2017a,
Miller 2017). Additional information about the status and trend of the United States population
is available in our annual reports (online at
https://www.fws.gov/southwest/es/mexicanwolf/documents.cfm) and the Biological Report for the
Mexican Wolf, the latter of which also includes a more detailed discussion of the genetic
condition of the United States population (USFWS 2017a, Miller 2017).

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Mexico Reintroductions: Mexico began reintroducing Mexican wolves to the wild in 2011 and,
as of 2017, is still in the establishment phase of their reintroduction effort. Forty-one wolves
have been released in the first 5 years of the reintroduction, including both releases from
captivity and Mexican wolves translocated from the wild population in the United States to
Mexico. As of July 2017, approximately 31 wild Mexican wolves inhabit Chihuahua and
Sonora, Mexico, in the northern Sierra Madre Occidental (CONANP 2017, Garcia Chavez et al.
2017). Mexico is continuing to release captive or translocated Mexican wolves to help increase
abundance until such time as natural reproduction is sufficient to sustain the population. One
wild pair in Mexico has reproduced in three of its four years in the wild (USFWS 2017a), and
their pups are successfully establishing wild packs with other released animals.
The focal areas for Mexican wolf recovery in the United States and northern Sierra Madre
Occidental are approximately 260 miles (mi) (418 kilometers [km]) from each other (when
measured from the center of one area to the other), a distance within the natural dispersal
capabilities of the Mexican wolf. However, the distance between nearest high-quality habitat
patches in both areas is approximately 96 mi (155 km). The proximity of these areas is such that
Mexican wolves have the potential to move between populations depending on survival and how
they are managed during dispersal events. Since reintroductions began, two Mexican wolves are
known to have crossed the border from Mexico into the United States (USFWS, our files).
Neither Mexican wolf became established in the United States: one returned to Mexico and one
was captured and placed in captivity.

Introduction and Background

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II.

NOVEMBER 2017

THREATS TO THE MEXICAN WOLF

We assess “threats” to a species during our determination of whether a species is threatened or
endangered due to any of the five factors in the ESA:
A)
B)
C)
D)
E)

the present or threatened destruction, modification, or curtailment of its habitat or range;
overutilization for commercial, recreational, scientific, or educational purposes;
disease or predation;
the inadequacy of existing regulatory mechanisms; and
other natural or manmade factors affecting its survival.

In our listing of the Mexican wolf as an endangered species, we conducted a detailed five-factor
analysis of threats and determined that the Mexican wolf was in danger of extinction due to
illegal shooting, genetic issues (inbreeding, loss of heterozygosity, and loss of adaptive
potential), and small population size (80 FR 2488). In the Biological Report (USFWS 2017a),
we provide an in-depth description of four “stressors” -- conditions that may influence the
current and ongoing recovery potential of the Mexican wolf: 1) adequate habitat
availability/suitability; 2) excessive human-caused mortality; 3) demographic stochasticity
associated with small population size; and 4) continuing or accelerated loss of genetic diversity
in the captive or wild populations. Stressors and threats are highly related concepts, but may not
be one and the same for a species. For example, for the Mexican wolf, habitat destruction,
modification, or curtailment (Factor A) is not threatening or endangering the Mexican wolf, yet
ensuring adequate habitat is available to support recovered Mexican wolf population into the
future is central to the recovery effort for the Mexican wolf (e.g., a potential stressor).
Within the context of the recovery plan, we consider the threats to the Mexican wolf to be
excessive human-caused mortality (which includes shooting and other sources), demographic
stochasticity associated with small population size, and loss of gene diversity. We provide
discussion of each of these threats and the stressors noted above in the Biological Report
(USFWS 2017a). We further address these threats in our Rationale for Recovery Criteria, and
identify recovery actions to alleviate each threat.

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III. RECOVERY STRATEGY
For any species, there may be several strategies that provide a valid path to recovery. This is the
case for the Mexican wolf – different combinations of the location, number of populations, and
number of wolves could alleviate the threats of human-caused mortality, lack of gene diversity,
and extinction risk due to small population size. Our recovery strategy, which is based on the
current status of the Mexican wolf in the wild and the threats it faces, is to establish and maintain
a minimum of two resilient, genetically diverse Mexican wolf populations distributed across
ecologically and geographically diverse areas in the subspecies’ range in the United States and
Mexico. Our recovery strategy addresses the threats of human-caused mortality, extinction risk
associated with small population size, and loss of gene diversity (USFWS 2017a, Miller 2017).
Moreover, it ensures that Mexican wolf populations can achieve the resiliency, representation,
and redundancy needed to downlist and delist the Mexican wolf, as described in the Rationale
for Recovery Criteria. At the time of recovery, we expect viable Mexican wolf populations that
are stable or increasing in abundance, well-distributed geographically within their range, and
genetically diverse.
We developed this binational recovery strategy for the Mexican wolf in coordination with federal
agencies in Mexico and state, federal, and Tribal agencies in the United States. Management of
listed species in areas outside of the United States is primarily the responsibility of the countries
in which the species occur. However, partners in the United States and Mexico will cooperate to
conserve and recover the Mexican wolf throughout its range.
The concepts of resiliency, redundancy, and representation are:
Resiliency describes the ability of populations to withstand stochastic events. Measured
by the size and growth rate of each population, resiliency is important because it gauges
the probability that the populations comprising a species are able to withstand or bounce
back from environmental or demographic stochastic events.
Redundancy describes the ability of a species to withstand catastrophic events. Measured
by the number of populations, their resiliency, and their distribution (and connectivity),
redundancy is important because it gauges the probability that the species has a margin of
safety to withstand or can bounce back from catastrophic events.
Representation describes the ability of a species to adapt to changing environmental
conditions. Measured by the breadth of genetic or environmental diversity within and
among populations, representation is important because it gauges the probability that a
species is capable of adapting to environmental changes.
The primary components of our recovery strategy include expanding the geographic distribution
of the Mexican wolf, increasing population abundance, improving gene diversity in the wild,
monitoring wild populations and implementing adaptive management, and collaborating with
partners to address social and economic concerns related to Mexican wolf recovery.

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Geographic Distribution
In the United States, we are focusing implementation of the recovery strategy for the Mexican
wolf in the area south of Interstate 40 in Arizona and New Mexico. In Mexico, federal agencies
are focusing Mexican wolf recovery efforts in the northern Sierra Madre Occidental in
Chihuahua and Sonora (Figure 3).
Our strategy is to establish two populations over a large geographical area of the Mexican wolf’s
range to address the conservation principles of redundancy and representation (both ecological
and geographical), as discussed in the Rationale for Recovery Criteria. We are focusing
recovery implementation in the United States in the area south of Interstate 40, consistent with
the range described by Parsons (1996), which the Service previously adopted when we began
reintroducing wolves in 1998 (63 FR 1752). In Mexico, federal agencies are currently focusing
Mexican wolf recovery efforts in the northern Sierra Madre Occidental (Figure 3). Recent
habitat and population viability modeling (Martínez-Meyer et al. 2017, Miller 2017) support our
geographic focus because they predict that each of these areas in the United States and Mexico
can support a viable Mexican wolf population.
United States: Recovery in the United States will continue to focus on one large population of
Mexican wolves south of Interstate 40 in Arizona and New Mexico. This area contains a large
expanse of contiguous high-quality habitat along the Mogollon Rim in central Arizona into west
central New Mexico, as well as other patches of high- and low-quality habitat (USFWS 2014;
Martínez-Meyer et al. 2017). Management of Mexican wolves in this area is governed by the
regulations for the nonessential experimental population of the Mexican wolf (80 FR 2512).
Mexico: In Mexico, there are two large blocks of high-quality habitat in the Sierra Madre
Occidental that are connected by areas of lower quality habitat and small interstitial patches of
high-quality habitat (Martínez-Meyer et al. 2017); we refer to these two areas as the northern
Sierra Madre Occidental and southern Sierra Madre Occidental (Figure 3). Based on recent
habitat modeling, we expect that either of these areas will be able to support a population of
Mexican wolves (Martínez-Meyer et al. 2017). Current reintroduction efforts are focused in the
northern Sierra Madre Occidental due to logistical considerations (e.g., monitoring wolves in a
single area rather than spreading resources between the northern and southern areas), and
therefore the recovery strategy in Mexico focuses on this area. However, if Mexican wolves
disperse to southern Sierra Madre Occidental or federal agencies in Mexico decide to release
Mexican wolves into this area as part of their reintroduction effort, the recovery strategy can be
adapted to include wolves in either or both areas (Miller 2017). We have not identified large
enough blocks of high-quality habitat in the Sierra Madre Oriental region to support a population
of sufficient size to contribute to complete recovery under the ESA (Martínez-Meyer et al. 2017),
although this does not preclude Mexico from pursuing reintroduction in this area pursuant to
their laws and regulations.

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Figure 3. Focal areas for Mexican wolf recovery in the United States and Mexico. (Habitat quality from Martínez-Meyer et al. 2017, titled
“Figure 22. Rescaled intermediate habitat suitability scenario for the Mexican wolf based on the combination of climatic suitability, land cover
use, human population density, road density, and UBI.”)

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Population Abundance
We will increase the abundance of Mexican wolf populations in the United States and Mexico
from their current size to an abundance that confers a low probability of extinction.
As population abundance increases, the threat of demographic stochasticity decreases and
population resiliency increases (Goodman 1987; Pimm et al. 1988; and see discussion in USFWS
2017a; 80 FR 2488; and, USFWS 2010). Currently, both the United States and Mexico
populations are at risk of extinction due to their small population size (USFWS 2017a, including
Miller 2017). Therefore, both populations will need to increase in abundance sufficient to
ameliorate this risk. We consider a population that has at least a 90% probability of persistence
over 100 years to contribute to achieving recovery criteria, as described in our Rationale for
Recovery Criteria. In the United States, population growth will likely continue to be driven
primarily by natural reproduction. In the smaller Mexican wolf population in Mexico,
population growth can be stimulated by the continued release of a substantial number of Mexican
wolves from captivity to the wild, translocations, and population growth from natural
reproduction increasing over time as more wolves become established in the wild.
Our strategy to establish populations of sufficient size to reduce extinction risk addresses the
conservation principle of resiliency, as discussed further in the Rationale for Recovery Criteria.
Genetic Management
To improve gene diversity of Mexican wolf populations in the wild, we will release and
translocate Mexican wolves, as needed.
As of June 2017, the captive population has higher gene diversity than either of the wild
populations, and both wild populations are at risk of future genetic issues unless gene diversity
can be improved (USFWS 2017a). The release of Mexican wolves from captivity to the wild can
result in a substantial amount of the gene diversity available in captivity being represented in the
wild. In this Plan, we aim to ensure wild populations represent approximately 90% of the gene
diversity retained by the captive population to provide for representation. Release strategies
from captivity may include the release of individual or paired adult wolves, a pack of wolves, or
cross-fostering of pups. (Cross-fostering has been successful in other carnivores, but is a
relatively new technique for Mexican wolves. Using this technique, we place captive-born pups
into wild dens to be raised with the wild litter. We use this technique to improve the gene
diversity of the wild population). Each of these release strategies has benefits and challenges
that can be considered, in addition to new strategies that may arise in the future, within the
opportunities and limitations of the release event and progress toward recovery. Translocation of
wolves between wild populations can also be a source of gene diversity to the recipient
population and will be considered as a way to improve the gene diversity of wild populations.
In order to achieve the genetic criteria for downlisting and delisting the Mexican wolf in this
Plan, decisions regarding the timing, location and circumstances of Mexican wolf releases will
be based on input from the Interagency Field Team, and will be made cooperatively by the
Service with the Arizona Game and Fish Department with respect to releases in Arizona, and by
the Service with the New Mexico Department of Game and Fish with respect to releases in New
Mexico. Additionally, prior to any releases occurring, the Service will comply with state permit

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requirements pursuant to (i) 43 C.F.R. pt. 24 and (ii) conditions imposed by any permit issued
under section 10(a)(1)(A) of the Endangered Species Act, 16 U.S.C. 1539(a)(1)(A).
Released wolves (including both releases from captivity and translocated wolves) contribute
their gene diversity to the recipient population when they breed and produce offspring. We will
focus on the number of released wolves that survive to breeding age as our method of tracking
progress toward achieving the gene diversity criterion, in concordance with Miller (2017). We
estimate that an adult female of breeding age has a 78% likelihood of pairing with a male, and,
once paired, has approximately a 68% likelihood of producing a litter, as a function of age and
inbreeding (Miller 2017). Currently, many released wolves die within the first year of release,
and released Mexican wolves in both wild populations have lower survival during that time than
Mexican wolves born in the wild that are not associated with a release event (see Miller 2017 for
data on release survival). The low survival of released wolves results in the need to release
enough wolves that a sufficient number survive to breeding age. Management to improve the
survival of released wolves will decrease the number of releases needed to achieve recovery
criteria.
Our strategy to address the conservation principle of (genetic) representation, as discussed
further in the Rationale for Recovery Criteria, is to release wolves from captivity to the wild and
translocate wolves between populations to ensure wild populations benefit from the gene
diversity available in the captive population. Population viability analysis by Miller (2017) has
identified several combinations of releases and translocations that will achieve genetic
representation, and we expect that other combinations are also possible.
The gene diversity of wild Mexican wolf populations can also be influenced through the
dispersal of wolves from one wild population to another. We expect the patchy habitat in the
border region of Mexico and the United States, as modeled by Martínez-Meyer et al. (2017), has
the potential to support a low level of Mexican wolf dispersal between high-quality habitat
patches in the United States and the northern Sierra Madre Occidental (about one wolf every 1216 years; Miller 2017). As of 2017, the international border between the United States and
Mexico has segments with no fence and with vehicle fence, both of which are permeable to
wolves, as well as segments with pedestrian fence, which is not permeable to wolves (USFWS
2017a). Habitat quality between the northern and southern Sierra Madre Occidental sites in
Mexico has the potential to support a higher degree of dispersal compared with the potential
between the United States and northern Sierra Madre Occidental site, but it is still predicted to be
low (about one wolf every 3-4 years; Miller 2017). While we anticipate habitat between any of
the populations can support dispersing wolves and provide some connectivity, we do not expect
the level of dispersal predicted between any of the sites (particularly between the United States
and northern Sierra Madre Occidental) to provide for adequate gene flow between populations to
alleviate genetic threats or ensure representation of the captive population’s gene diversity in
both populations. Therefore, we consider genetic management such as releases from captivity
(including cross-fostering pups) and translocations to serve as an effective tool during the
recovery process to achieve appropriate representation (Miller 2017). Thus, releases and
translocations are a form of management that is necessary during portions of the recovery
process. We do not expect regular releases from the captive population to be necessary after
Mexican wolves have been recovered because a high proportion of the gene diversity from

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captivity will have been incorporated into the wild populations and wild populations will be
sufficiently abundant such that releases from captivity for population augmentation will not be
necessary (Miller 2017). While releases and translocations are necessary for portions of the
recovery process, we recognize the benefits of habitat connectivity and will work to maintain and
enhance connectivity within and between Mexican wolf populations to improve gene diversity of
Mexican wolves. We note, however, that connectivity or successful migrants are not required to
achieve recovery (see addendum in Miller 2017).
Monitoring and Adaptive Management
We will conduct ongoing annual monitoring to track Mexican wolf population performance, and
we will adjust management techniques and approaches as needed in response to population
performance.
Our monitoring will continue to focus on annual population growth, recognizing the relationship
between recruitment and mortality (i.e., high recruitment may offset high mortality rates). Wolf
mortality, combined with removal of wolves for management purposes (which functions as
mortality to the population), will need to stay below threshold levels such that populations can
achieve abundance targets. The majority of documented mortalities in the United States are
human-caused (USFWS 2017a); therefore, reducing mortalities from human-caused sources such
as shooting and vehicle collision may provide our best opportunity to improve population
performance and speed the time to recovery. Similarly, management removal of Mexican
wolves in response to depredation incidents and conflict with humans has been the biggest
source of removal and can impact population performance. Between 2003 and 2009, we
observed the negative impact that a high number of removals can have on population
performance in the United States, and in response, we reduced our removal rate by focusing on
working with landowners and permittees to implement proactive management techniques such as
range riders, fladry, non-lethal ammunitions, and diversionary feeding to decrease the likelihood
of depredation incidents. Diversionary food caches are road-killed native prey carcasses or
carnivore logs (commercially manufactured raw horse meat-based diet especially formulated for
carnivores) provided to denning wolves to reduce potential conflicts with livestock in the area.
In the United States, our recovery strategy will entail adaptively managing our removal rate of
Mexican wolves in response to documented mortality during the previous year to ensure that
mortality is not hindering population growth over multiple years. Therefore, we will employ
management actions to work to reduce wolf-livestock and wolf-human conflict through the
implementation of pro-active measures to avoid and minimize depredation; facilitate the
provision of compensation for the economic impact of wolves on rural ranching communities;
and employ a phased management approach in Arizona to minimize or avoid possible adverse
impacts to wild ungulate populations (specifically elk). We will also allow take of Mexican
wolves under specific circumstances, and continue to work collaboratively with state and local
governments, tribes, livestock producers, state game and fish departments, and stakeholder
organizations to achieve the social tolerance for wolves in rural communities necessary to
achieve Mexican wolf recovery. We expect that Mexico will conduct similar monitoring of
Mexican wolves to track population performance and adapt management strategies as needed.

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Monitoring of wild Mexican wolf populations will help us annually track our progress in
achieving the resiliency, representation, and redundancy necessary for recovery. In addition, we
have provided evaluation periods at 5 and 10 years after we begin implementing the recovery
plan to evaluate whether the recovery strategy is effective and progress toward recovery is
occurring as predicted.
Collaborative Recovery Implementation
We will continue to work with partners to identify and implement effective recovery actions
necessary to recover the Mexican wolf and address conflicts related to Mexican wolf recovery in
local communities.
The recovery of the Mexican wolf has been a collaborative effort since its earliest days.
Effective recovery requires participation by multiple parties within Federal, state, and local
governments; nongovernmental organizations; academia; and local communities. We have
strong partnerships with the Species Survival Plan captive breeding facilities in the United States
and Mexico. We also collaborate with Federal, state, county, and Tribal agencies through a
Memorandum of Understanding and the establishment of the Mexican Wolf Interagency Field
Team, which conducts the reintroduction, management, and monitoring of Mexican wolves in
the United States. We intend to maintain and strengthen the interagency partnerships currently
in place for the United States population.
Section 6 (a) of the ESA directs the Service to cooperate to the maximum extent practicable with
the states (59 FR 34275), and Secretarial Orders 3175 and 3206 and the Service’s Native
American Policy (2016) require consultation with tribes in the recovery of listed species.
Opportunities for increasing levels of state and tribal management are currently available under
the 10(j) rule and will continue to be explored as recovery progresses. When the status of the
Mexican wolf has improved sufficiently to downlist it to threatened, we may consider
establishing a 4(d) rule under the ESA. The Service uses 4(d) rules to incentivize positive
conservation actions and streamline the regulatory process for minor impacts. As part of those
goals, the rule is often used to clarify or simplify what forms of take of a threatened species
are/are not prohibited wherever the animals may occur. Establishment of a 4(d) rule after the
status of the Mexican wolf has improved to “threatened” would provide the state wildlife
agencies increased management flexibility. The Service would first publish a proposed rule in
the Federal Register and seek public comment and peer review before making a decision on the
action.
Addressing wolf-livestock conflicts is one of the most important areas for collaborative
management of Mexican wolves. Depredation compensation is currently available through:
•

the Farm Bill Livestock Indemnity Program, which is administered by the Farm Services
Agency (see https://www.fsa.usda.gov/programs-and-services/disaster-assistanceprogram/livestock-indemnity/index);

•

the Arizona Livestock Loss Board (see https://www.azgfd.com/Agency/LivestockBoard/;
and

•

the Mexican Wolf/Livestock Council (see http://www.coexistencecouncil.org/).

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The Mexican Wolf/Livestock Council is an 11-member group of livestock producers, Tribes,
county representatives, and environmental groups appointed by the Service. The Service will
continue seeking additional funding for these programs to offset Mexican wolves’ direct and
indirect costs to livestock producers.
Due to the binational range of the Mexican wolf, successful recovery of the species requires
close coordination and cooperation with recovery partners in Mexico. The Service has a strong
working relationship with the Mexican governmental agencies CONANP and Secretaría del
Medio Ambiente y Recursos Naturales (SEMARNAT), as well as field staff working to
reestablish the Mexican wolf in the wild in Mexico. Section 8 (b) of the ESA encourages foreign
countries to provide for the conservation of threatened and endangered species, and the Service
to enter into agreements with foreign countries to provide for such conservation. Our
relationship with the Mexican government is formalized through a 1996 Memorandum of
Understanding establishing the Canada/Mexico/United States Trilateral Committee for Wildlife
and Ecosystem Conservation and Management. The Service and our state partners will continue
to seek funding to assist Mexico in implementing actions necessary to achieve Mexican wolf
recovery. In addition, the Service and our partners will continue to exchange technology and
expertise with Mexico to implement recovery actions.

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IV. RECOVERY GOAL, OBJECTIVES, AND CRITERIA
Recovery Goal:
The recovery goal is to conserve and protect the Mexican wolf and its habitat so that its longterm survival is secured, populations are capable of enduring threats, and it can be removed from
the list of threatened and endangered species.
Recovery Objectives:
Recovery objectives identify outcomes that will lead to achieving the goal of recovery and
delisting. Recovery objectives for the Mexican wolf are:
1.
2.
3.
4.

Increase the size of two Mexican wolf populations;
Improve gene diversity and maintain the health of Mexican wolves;
Ensure adequate habitat availability to support viable Mexican wolf populations;
Maintain the Mexican Wolf Species Survival Plan (SSP) captive breeding program to
improve the status of wild populations;
5. Promote Mexican wolf conservation through education and outreach programs; and
6. Ensure recovery success.
Recovery Criteria:
Recovery criteria serve as objective, measurable guidelines to assist in determining when an
endangered species has recovered to the point that it may be downlisted to threatened, or that the
protections afforded by the ESA are no longer necessary and the Mexican wolf may be delisted.
Delisting is the removal of a species from the Federal Lists of Endangered and Threatened
Wildlife and Plants. Downlisting is the reclassification of a species from Endangered to
Threatened. The term “endangered species” means any species (species, sub-species, or DPS)
which is in danger of extinction throughout all or a significant portion of its range. The term
“threatened species” means any species which is likely to become an endangered species within
the foreseeable future throughout all or a signification portion of its range.
All classification decisions consider the following five factors: 1) is there a present or threatened
destruction, modification, or curtailment of the species’ habitat or range; 2) is the species subject
to overutilization for commercial, recreational scientific or educational purposes; 3) is disease or
predation a factor; 4) are there inadequate existing regulatory mechanisms in place outside the
ESA (taking into account the efforts by the states and other organizations to protect the species
or habitat; and 5) are other natural or manmade factors affecting its continued existence. When
delisting or downlisting a species, we first propose the action in the Federal Register and seek
public comment and peer review. Our final decision is announced in the Federal Register.
We provide both downlisting and delisting criteria for the Mexican wolf as follows:
Downlisting Recovery Criteria
Option 1:

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The Mexican wolf will be considered for downlisting when:
a) The United States population average over a 4-year period is greater than or equal to 320
Mexican wolves; and
b) Gene diversity available from the captive population has been incorporated in the United
States population through the scheduled releases of wolves surviving to breeding age as
identified in delisting criteria.
-orOption 2:
The Mexican wolf will be considered for downlisting when a minimum of two populations (one
in the United States and one in Mexico) meet abundance and genetic criteria as follows:
a) Each population average over the same 4-year period is greater than or equal to 150
wolves with an annual positive population growth rate; and
b) Gene diversity available from the captive population has been incorporated into both the
United States and Mexico populations through the scheduled releases of wolves surviving
to breeding age as identified in delisting criteria.
Delisting Recovery Criteria
The Mexican wolf will be considered for delisting when:
1. A minimum of two populations meet all abundance and genetic criteria as follows:
United States
a) The population average over an 8-year period is greater than or equal to 320 wolves (e.g.,
annual wolf abundance of 200, 240, 288, 344, 412, 380, 355, and 342 averages 320
wolves);
b) The population must exceed 320 wolves each of the last 3 years of the 8-year period;
c) The annual population growth rate averaged over the 8-year period is stable or increasing
(e.g., annual averages of 1.2, 1.2, 1.2, 1.2, 1.2, 0.9, 0.9, and 1.0 averages 1.1); and
d) Gene diversity available from the captive population has been incorporated into the
United States population through scheduled releases of a sufficient number of wolves to
result in 22 released Mexican wolves surviving to breeding age in the United States
population. “Surviving to breeding age” means a pup that lives 2 years to the age of
breeding or an adult or subadult that lives for a year following its release. “Scheduled
releases” means captive releases and translocations that achieve genetic representation, as
described in Rationale for Recovery Criteria.
Mexico
a) The population average over an 8-year period is greater than or equal to 200 wolves;
b) The population must exceed 200 wolves each of the last 3 years of the 8-year period;

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c) The annual population growth rate averaged over the 8-year period is stable or
increasing; and
d) Gene diversity available from the captive population has been incorporated into the
Mexico population through scheduled releases of a sufficient number of wolves that
results in 37 released Mexican wolves surviving to breeding age in the Mexico
population. “Surviving to breeding age” means a pup that lives 2 years to the age of
breeding or an adult or subadult that lives for a year following its release. “Scheduled
releases” means captive releases and translocations that achieve genetic representation, as
described in Rationale for Recovery Criteria.
-and2. States and Tribes will ensure regulatory mechanisms are in place to prohibit or regulate
human-caused mortality of Mexican wolves in those areas necessary for recovery such that
the Service determines at least 320 Mexican wolves are likely to be maintained in the United
States in the absence of Federal ESA protections. In addition, Mexico will ensure regulatory
mechanisms are in place to protect Mexican wolves from human-caused mortality, such that
the Service determines at least 200 Mexican wolves are likely to be maintained in Mexico.
Rationale for Recovery Criteria
Resiliency
The abundance criteria ensure that populations are resilient and the threats of demographic
stochasticity and human-caused mortality have been ameliorated. We consider a resilient
population to be one that is able to maintain at least a 90% likelihood of persistence over a 100year period. This benchmark falls within the community of practice of recent recovery plans
assessed by Doak et al. (2015). In addition, we consider a population to be resilient when it has
an average annual growth rate that is stable or increasing (i.e., lambda ≥ 1) over the 8-year
timeframe and is above its abundance criterion in years 6, 7, and 8. At this level of resiliency,
the threat of demographic stochasticity has been ameliorated because the population is secure
from random population fluctuations, and mortality rates are sufficiently low to allow for stable,
long-term persistence of the populations (USFWS 2017a).
Based on population viability modeling, we predict the United States and Mexico populations
will achieve resiliency when an average population of 320 and 200 Mexican wolves,
respectively, can be maintained for 8 years (Miller 2017). Establishing a criterion for an average
abundance means that in some years the populations may exceed abundance targets (320 and
200, respectively for the United States and Mexico populations), while in some years they may
fall below their target; this is consistent with the annual population fluctuations predicted by
population viability modeling results (Miller 2017). Years in which the population grows above
320 are expected and will enable progress toward the abundance criterion for the United States
population more quickly than when the population hovers at or near 320.
Mortality rates will need to be sufficiently low to achieve recovery criteria because they are a
primary indicator of wolf population trajectory (Fuller et al. 2003). Previous gray wolf studies
have primarily pooled mortality rates across age classes for pups older than approximately 6
months, yearlings, and adults (Fuller et al. 2003, Adams et al. 2008). Miller’s (2017) results

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were based on estimated mortality rates for Mexican wolves in each of the three age classes.
Thus, Miller (2017) results are not necessarily directly comparable to other studies. Miller
(2017) scenarios with mean adult mortality rates less than 25%, combined with mean sub-adult
mortality rates less than 33% and mean pup mortality (for radio-marked pups greater than 4
months old) less than 13% resulted in an increasing population that meet the population
abundance recovery criteria, under certain management regimes. In agreement with the results
of Carroll et al. (2014), population performance in Miller’s results was highly sensitive to
relatively small changes in adult mortality rate. Miller’s results are consistent with metaanalyses that suggest a wolf population should stabilize with an overall average mortality rate of
34% (Fuller et al. 2003). Miller’s results indicate the populations need to perform at mortality
rates lower than Fuller et al. (2003) because: (1) the Mexican wolf population needs to exhibit
growth (rather than stability) to achieve recovery, (2) the results are based on specific
characteristics of the Mexican wolf population rather than wolves in general, and (3) other
studies of wolf population growth are significantly influenced by immigration and emigration
(Adams et al. 2008), and we do not predict significant natural rates of immigration or emigration
between the Mexican wolf populations (Miller 2017). Miller’s results are also consistent with
growing wolf populations in central Idaho and the Greater Yellowstone area (Smith et al. 2010).
The mean mortality rate utilized for Miller’s results incorporates human-caused mortality and
demonstrates that Mexican wolf populations will still be stable or increasing.
We consider an acceptable mortality rate during the recovery process to be one where the
population grows toward or is maintained at the desired population abundance. Thus, the
average mortality rates could change over time based on management goals and additional data.
We expect to adaptively manage the population to reduce or increase removals based on
documented mortality from other causes during the previous year to ensure that the mean
mortality rate over several years does not exceed those identified by Miller (2017).
Miller (2017) suggests there is a functional relationship between the inclusion of diversionary
feeding and the number of pups produced in that population. Therefore, removal of diversionary
feeding can lead to a decrease in the population growth rate for a given level of annual adult
mortality. Miller (2017) evaluated the impact of removing diversionary feeding for both the
United States and Mexico populations in a select set of PVA scenarios. The results of these
analyses indicate that reducing adult mortality is necessary when diversionary feeding is
significantly reduced or eliminated (see Addendum in Miller 2017). However, we expect to
continue a low level of diversionary feeding to reduce conflicts between livestock and wolf
packs rearing pups.
To ensure populations have a high likelihood of maintaining resiliency, they must meet the
average population abundance targets for 8 consecutive years. Eight years provides an
appropriate amount of time to observe the populations’ demographic performance for several
reasons. First, an 8- year window is equivalent to approximately two wolf generations,
grounding the criteria in a biologically relevant timeframe. Observing the population for longer
than a single generation will provide assurance that population metrics such as reproduction and
mortality rates are fluctuating within expected levels at the target abundance and that populations
are performing such that recovered status is likely to be maintained after delisting. Specifically,
it allows us to observe population trend, which we expect to be stable or growing as populations

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achieve recovery, although we also expect annual fluctuations could include population declines
for one or a few years during an 8-year period. We estimate that an 8-year period will include
one catastrophe cycle (i.e., an event of extreme pup mortality, as described in Miller 2017),
allowing us to ensure that the population is able to rebound following such an event.
Downlisting criteria require only a single generation (4 years) because protections under
threatened status would remain in place to ensure that populations remain robust through various
population cycles. We would not downlist or delist the Mexican wolf if population performance
demonstrates that wolf populations are unstable (e.g., populations have not rebounded from a
catastrophe cycle).
Based on Miller (2017), we predict that recovery could be reached within 25-35 years (i.e., about
2043 to 2053). This includes the time to reach the abundance and genetics targets in both
countries and achieve the population averages indicated in the criteria. However, recovery could
be reached sooner if populations grow more rapidly than predicted (e.g., through lower mortality
rates, higher recruitment). Also based on Miller (2017), we predict downlisting could be
possible within approximately 16-20 years (i.e., about 2034 to 2038) (Miller 2017). Similarly,
downlisting could be reached sooner with more rapid population growth. Miller’s results are
useful for estimating the time frame to recovery assuming the conditions specified in the
population viability model are similar (which we expect) to those observed in the wild during
recovery implementation.
In the United States, we will focus our management to ensure a population of at least 320
Mexican wolves can be maintained. We recognize that unrestricted Mexican wolf population
growth may erode social tolerance in local communities or cause other management concerns,
such as unacceptable impacts to wild ungulates (USFWS 2014). We consider it not only
possible, but preferable, to achieve recovery while addressing the concerns of local communities
and economies. Therefore, we used the Vortex model to explore viability of populations that
were not allowed to increase over 380 Mexican wolves in the United States to simulate
management response to problem wolves and unacceptable impacts to native ungulate herds
(Miller 2017). While 380 Mexican wolves functioned as a population cap in the model, it was
not intended as a limit on the number of Mexican wolves in the wild. However, if population
growth is causing management concerns, we will consider any and all management options,
including allowing mortality rates to increase through permitted take or other mechanisms,
provided at least 320 Mexican wolves are likely to be maintained.
Representation
The gene diversity criterion ensures that Mexican wolf populations have genetic representation
and that genetic threats have been ameliorated, while having Mexican wolves across large
portions of their range ensures ecological representation. Ensuring gene diversity in the near
term will reduce the incidence of inbreeding depression, while over a longer timeframe it will aid
the Mexican wolf’s ability to respond and adapt to various and changing environmental
conditions.
We consider the degree to which wild populations contain the gene diversity (expected
heterozygosity) available from the captive population to be an important indication of genetic
representation for recovery (USFWS 2017a). Ensuring wild populations represent

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approximately 90% of the gene diversity retained by the captive population provides for
representation based on community of practice in the management of captive populations
(Siminski and Spevak 2017). Typically when captive populations are established from wild
populations, the goal is to retain at least 90% of the gene diversity available from the wild
population (Soulé et al. 1986). In the case of the Mexican wolf, we are applying this goal to
establish a wild population from a captive population. We consider approximately 90% to be
reasonable for recovery because it ensures wild populations contain a high degree of the gene
diversity available (Siminski and Spevak 2017), while recognizing that we cannot control
breeding events in the wild and need flexibility in our management of wolves (e.g., removal of
Mexican wolves from the wild for management purposes may positively or negatively affect the
gene diversity of the population). Miller (2017) identifies several release scenarios that are able
to achieve 90% gene diversity of the captive population in the wild by model year 20 (2035). It
is important to note that in the scenarios presented by Miller (2017), not all released wolves
incorporated into the population contribute offspring, and conversely, some released wolves
incorporated into the wild population will contribute offspring more than once. We would
expect to use one of these release scenarios or a comparable scenario to meet the scheduled
releases necessary to achieve the recovery criteria.
Release strategies from captivity may include the release of individual or paired adult wolves, a
pack of wolves, or cross-fostering of pups. The importance of the releases of Mexican wolves
from the captive population into the wild is demonstrated graphically in the PVA report (Miller
2017). Based on the current estimates of first year mortality of wolves released from captivity,
we estimate the need to release about 70 wolves to the United States population to have 22 of
them survive to breeding age. We estimate the need to release about 100 wolves to the wild
population in Mexico to have 37 of them survive to breeding age. The number of releases
required may increase or decrease if the survival of released wolves changes. We did not require
that a released or translocated wolf survive and produce offspring in the population, as the basis
for recovery criteria. We instead used a metric (i.e., number of animals that survive to breeding
age) that coupled model performance with performance of the wild populations. Including a low
level of dispersal/connectivity (approximately 1 wolf every 12 to 16 years), the model predicts
that at this level of release and at the predicted first year mortality rate we will achieve gene
diversity in the wild population of approximately 90% of that retained in the captive population
(Miller 2017).
The extent to which released Mexican wolves are able to influence the gene diversity of a wild
population is a function of the number of released wolves that survive and breed in relation to the
recipient population abundance (i.e., when releases represent a larger proportion of the recipient
population, they result in greater genetic and demographic effect). Therefore, the timing of
releases of wolves in relation to population size and whether or not they survive to breeding age
are critical factors in the degree to which releases will ensure that approximately 90% of the gene
diversity available in captivity is represented in each wild population. For this reason, it will be
important for us to establish a schedule of releases that achieves the recovery criteria (Actions
2.1, 2.2, and 2.3 in Table 1).
We consider all releases subsequent to December 2015 to contribute to the genetic criteria for the
United States and all releases subsequent to December 2016 to contribute to the genetic criteria

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for Mexico. These are appropriate starting dates because Miller’s (2017) scenarios were initiated
with the pedigree of both populations as of December 2015, but Mexico’s 2016 releases were
included in the first time step of the model due to the large number of releases that year and the
resultant effect on the population’s genetic and demographic condition.
We will achieve ecological representation by the distribution of Mexican wolves across large
portions of their historical range (per Parsons 1996) in the United States and Mexico, namely
within Arizona and New Mexico south of Interstate 40 and in the northern Sierra Madre
Occidental. Martínez-Meyer et al. (2017) estimate 44,477 km2 (17,173 mi2) of high quality
habitat in Arizona and New Mexico south of Interstate 40, 21,538 km2 (8,316 mi2) in the
northern Sierra Madre Occidental, and 34,540 km2 (13,339 mi2) in the southern Sierra Madre
Occidental under the intermediate scenario with ungulate biomass index. Habitat conditions vary
between the United States and Sierra Madre Occidental sites in both terrain and vegetation, as
well as the abundance and distribution of prey (USFWS 2017a). These differences will expose
the Mexican wolf genome to different environments that may result in different selection
pressures. We anticipate more genetically diverse wild populations in the United States and
northern Sierra Madre Occidental will be better able to respond to not only the current range of
habitat conditions, but also future changing conditions such as shifts in prey availability, drought,
or other environmental fluctuations. Variation in environmental conditions (such as drought,
fire, and prey fluctuations) and episodic threats, such as disease, are characteristic of wild
populations of most species, including Mexican wolves. Mexican wolf populations that are
genetically robust will be more likely to recover from episodic threats (USFWS 2010). While
we do not consider climate change to be a threat to the Mexican wolf (see our discussion at 80
FR 2488), we recognize that climatic conditions are changing and may consider establishing
populations with genetic representation in ecologically/geographically varied habitat to provide
Mexican wolves with the potential to withstand these changes.
Redundancy
The establishment of two resilient populations of Mexican wolves with genetic and ecological
representation provides for redundancy (USFWS 2017a). Redundancy provides for security
against extinction from catastrophic events that could impact a single population by ensuring that
one or more additional resilient, representative populations persist. Our recovery criteria require
a minimum of two demographically and environmentally independent populations (e.g., limited
dispersal) such that negative events (e.g., disease, severe weather, natural disasters) are unlikely
to affect both populations simultaneously (Allendorf and Luikart 2007). In addition, both
populations are independently resilient and could be used as a source for reestablishment if
severe catastrophes were to occur in a single population. As modeled by Martínez-Meyer et al.
(2017), within the historical range of the Mexican wolf (Parsons 1996) there are areas of highquality habitat in Mexico and the United States of sufficient size to establish redundant
populations that are resilient.
The Need for Regulatory Protection
Prior to delisting, we will ensure that the state and tribal agencies that will be responsible for
maintaining the recovered status of the Mexican wolf have adequate regulations in place to
ensure levels of human-caused mortality will enable the population to retain the population
abundance specified by the abundance criterion in the United States. We will collaborate with

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these agencies during the implementation of the recovery plan as needed to prepare for a change
in management from federal to state and tribal regulatory control of the Mexican wolf.
Additionally, Mexico will also ensure that regulations are in place to manage levels of humancaused mortality to enable the population to retain the population abundance specified by the
abundance criterion in Mexico.
Explanation of Downlisting Criteria
The downlisting criteria are intended to demonstrate that the status of the Mexican wolf has
improved such that it is no longer endangered. We provide two options for downlisting the
Mexican wolf to threatened status: the United States population achieves abundance and genetic
criteria but Mexico does not, or both populations reach a partial level of genetic and
demographic stability, but neither population has fully reached its desired population abundance
target.
The first option for downlisting is appropriate if the United States population has achieved the
abundance criterion for 4 (one wolf generation) of the 8 years, and releases of wolves to provide
gene diversity (representation) have been conducted. This population will be close to achieving
resiliency and will have achieved representation, but the redundancy provided by the second
population will not yet be achieved.
The second option (i.e., both populations reach an average population abundance of 150 for 4
years, and releases of wolves to provide gene diversity have been conducted) demonstrates that
progress toward redundancy is substantial and representation has been achieved. In this
situation, neither population’s abundance is sufficient to achieve resiliency, but both would be on
track to becoming resilient given their annual positive growth rate. The criterion of 150 Mexican
wolves is not intended as a proportion of the population abundance required for delisting, but
rather is an indicator of a population abundance that confers a level of genetic and demographic
stability (i.e., low extinction risk) under assumed rates of population growth. Given the
predicted level of genetic and demographic stability, the Mexican wolf would no longer be in
danger of extinction throughout all or a significant portion of its range (i.e., endangered).
As recovery of the Mexican wolf progresses, including but not limited to downlisting to
threatened status, we will explore management options with the states and tribes in the United
States to increase management flexibility and foster the conservation of the Mexican wolf, as
discussed in the Recovery Strategy.

Recovery Goal, Objectives, and Criteria

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V.

NOVEMBER 2017

EVALUATION OF THE RECOVERY STRATEGY AND PROGRESS TOWARD
RECOVERY

Due to the intensive logistical, economic, and socio-political nature of the Mexican wolf
recovery effort, it is critical to ensure that progress toward recovery is advancing in a timely
manner. Therefore, to determine whether the recovery strategy is proving effective, we will
evaluate its efficacy and the progress of the Mexican wolf population toward recovery 5 years
and 10 years after implementation of the recovery plan. In addition, we will conduct 5-year
species status reviews required under the Section 4(c)(2) of the ESA.
The timing of the 5- and 10-year reviews is based on calendar years following the signing of this
recovery plan. The PVA model was initiated using data through December 2015 (Miller 2017).
The interim abundance and release and translocation targets to be used in the 5- and 10-year
status reviews are derived from Vortex model years 7 and 12. This reflects the 2-year difference
between the start of the Vortex model (end of 2015) and the signing of the recovery plan (end of
2017).
5-Year Status Review (based on data through 2022):
In the first 5-year review of the recovery plan, we will assess the status of each population
contributing to recovery. The purpose of the assessment will be to identify each population’s
progress toward recovery criteria, as measured by:
•

Interim abundance targets of approximately 145 wolves in the United States and 100
wolves in Mexico;

•

Interim release and translocation targets of a sufficient number of wolves to result in
approximately 9 released wolves surviving to breeding age in the United States and 25
released and translocated wolves surviving to breeding age in Mexico.

Based on this information, we will identify aspects of population performance needing
improvement and will determine what actions are necessary to address identified needs. Our
evaluation will include the feasibility of the needed actions, including timelines, cost, and other
relevant considerations. To complete the review, we will update the Recovery Implementation
Strategy as needed.
10-Year Status Review (based on data through 2027):
In the second 5-year review of the recovery plan, we will assess the status of each population
contributing to recovery. The purpose of the assessment will be to identify each population’s
progress toward recovery criteria and determine whether the recovery strategy is proving
effective/feasible. Progress toward recovery will be measured by:
•

Interim abundance targets of approximately 210 wolves in the United States and 167
wolves in Mexico;

•

Interim release and translocation targets of a sufficient number of wolves to result in
approximately 16 released wolves surviving to breeding age in the United States and 37
released and translocated wolves surviving to breeding age in Mexico.

Evaluation of the Recovery Strategy and Progress

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Based on this information, in addition to findings of the 5-year status review, we will make a
determination that the recovery strategy is proving effective/feasible or needs to be revised. If
we determine the recovery strategy is effective but some elements of recovery implementation
need improvement, we will identify what needs to be improved, including actions to address
identified needs and the feasibility of conducting such actions such as timelines and costs. If we
determine the recovery strategy is not proving effective and the expected recovery level is not
achieved, we will identify the reasons for such finding and, if necessary, revisit the recovery
strategy and work with States and others to identify other areas with suitable habitat and
adequate prey to achieve recovery; change techniques used to address gene diversity; or
implement other substantive changes. Any such revised strategy should include revised
time/cost estimates necessary to achieve recovery based on necessary actions. We will revise the
Recovery Plan or Recovery Implementation Strategy as necessary.

Evaluation of the Recovery Strategy and Progress

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VI. ACTIONS NEEDED
Recovery actions, which were developed for each objective, guide site-specific activities to
address threats and achieve the recovery criteria. They are provided in the Recovery Action
Table below (Table 1). Implementation of the recovery actions will involve participation from
the States, Federal agencies, counties, local communities, Tribes, non-federal landowners, nongovernmental organizations, academia, and the public in the United States and Mexico.
Recovery actions, organized by recovery objective, are accompanied by estimates of the cost and
time required to achieve the plan’s goal to recover the Mexican wolf.
The site-specificity of the recovery actions is provided primarily at the geographic scale of the
population, e.g., the United States or Mexico. The Plan does not provide more specific locations
for actions for which the locations cannot be determined until future conditions are known. For
example, the Plan does not identify at which approved release site a future release may occur
several years from now because it is unknown whether a specific site will be available (e.g.,
depending on wolf distribution). Similarly, we do not know when or where events that require
law enforcement response will be necessary.
A separate Recovery Implementation Strategy provides additional detailed, site-specific nearterm activities needed to implement the actions identified in the recovery plan. We intend to
update the implementation strategy as frequently as needed by incorporating new information,
including the findings of the 5 and 10-year status reviews. The implementation strategy will
provide near-term (e.g., 1-5 years) activities that will be continually updated as recovery
implementation progresses. Therefore, we anticipate being able to provide a greater degree of
site-specificity in the implementation strategy than the recovery actions in the recovery plan. For
example, release locations will be determined based on present-year circumstances. We will
only revise the recovery actions in this recovery plan if there are needed changes based upon the
findings of our 5 and 10-year status reviews, or subsequent evaluation of progress toward
recovery.
As stated in the Disclaimer, recovery plans are advisory documents, not regulatory documents.
A recovery plan does not commit any entity to implement the recommended strategies or actions
contained within it for a particular species, but rather provides guidance for ameliorating threats
and implementing proactive conservation measures, as well as providing context for
implementation of other sections of the ESA, such as section 7(a)(2) consultations on Federal
agency activities, development of Habitat Conservation Plans, or the creation of experimental
populations under section 10(j).
Estimated Cost and Timing of Recovery
We expect the status of the Mexican wolf to improve such that we can achieve downlisting
criteria in approximately 16-20 years. We expect to achieve recovery in approximately 25-35
years for a total estimated cost of $178,439,000. This cost includes those borne by governmental
agencies and nongovernmental organizations in the United States and Mexico.
While recovery may take an estimated 25-35 years, we anticipate successfully implementing the
actions in the Recovery Action Table such that we can achieve recovery in 25 years; therefore,

Actions Needed

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NOVEMBER 2017

the total estimated cost to recovery is based on this 25-year timeframe. These timeframes are
based on expectation of full funding, implementation as provided for in the recovery plan and
implementation strategy, and full cooperation of binational partners.
Annual cost estimates to implement recovery actions for the first 5 years are as follows:
Year 1 = $7,123,000
Year 2 = $7,491,000
Year 3 = $7,771,000
Year 4 = $8,005,000
Year 5 = $8,065,000
The estimated cost to implement the first 5 years of recovery actions (i.e., intermediate steps
toward the goal of recovery) is $38,455,000.
The calculation of the total estimated cost to recovery is included in the Recovery Action Table
below, whereas, the cost of implementing the first 5 years of recovery is detailed in the
Implementation Schedule Table of the Recovery Implementation Strategy.
Acronyms Used In Recovery Action Table
AZGFD
Arizona Game and Fish and Department
AZLLB
Arizona Livestock Loss Board
BLM
Bureau of Land Management
CBP
U.S. Customs and Border Protection
CONAFOR
Comisión Nacional Forestal
CONANP
Comisión Nacional de Áreas Naturales Protegidas
CNOG
Confederación Nacional de Organizaciones Ganaderas
DOT
Department of Transportation
DOW
Defenders of Wildlife
FS
U.S. Forest Service
FSA
U.S. Department of Agriculture Farm Services Agency
FWS
U.S. Fish and Wildlife Service
GM
Grupo México-Unidad de manejo para la conservación de la vida silvestre
(UMA) Buenavista del Cobre
GN
Gendarmería Nacional
INECOL
Instituto de Ecología, A.C.-Estación Biológica Piedra Herrada
MFS
Mexican Field Staff
MWF
Mexican Wolf Fund
MWLC
Mexican Wolf/Livestock Council
NMDGF
New Mexico Department of Game and Fish
NPS
National Park Service
NRCS
Natural Resources Conservation Service
OVIS
Organización Vida Silvestre, A.C.-UMA La Mesa
PGR
Procuraduría General de la Republica
PROFEPA
Procuraduría Federal de Protección al Ambiente
SAGARPA
Secretaría de Agricultura, Ganadería, Desarrollo Rural, Pesca y Alimentación
SCT
La Secretaría de Comunicaciones y Transportes

Actions Needed

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SEMARNAT
SSP
TESF
UI
UNAM-FMVZ
UNAM-IB
UNM
USDA-WS
WMAT

Actions Needed

NOVEMBER 2017

Secretaría del Medio Ambiente y Recursos Naturales
Species Survival Plan
Turner Endangered Species Fund
University of Idaho
Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional
Autónoma de México
Instituto de Biología, Universidad Nacional Autónoma de México
University of New Mexico
U.S. Department of Agriculture - Wildlife Services
White Mountain Apache Tribe

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Table 1. Recovery Action Table: Estimated Cost, Time, and Priority for Recovery Actions for the Mexican Wolf
SITE-SPECIFIC ACTION i

RESPONSIBLE
PARTY

ESTIMATED
COST in FY18
(US dollars)

TREND of
COST over
TIME

ESTIMATED
TOTAL COST
ADDRESSES
PRIORITY iii
TIME
(US dollars) ii
THREAT iv
(years)

Objective 1: Increase the size of two Mexican wolf populations
1.1

Survey and monitor Mexican
wolves to determine
population status in the U.S.

FWS, AZGFD,
NMDGF

1,460,000

Stable

25

36,500,000

1

2, 3

1.2

Survey and monitor Mexican
wolves to determine
population status in Mexico

CONANP, MFS

220,000

Increasing

25

12,120,000

1

2, 3

1.3

Monitor Mexican wolves on
Fort Apache Indian
Reservation

WMAT, FWS

225,000

Stable

25

5,625,000

1

2, 3

1.4

Monitor Mexican wolves on
other Tribal lands

Tribes, FWS

20,000

Increasing

25

3,920,000

2

2, 3

See Action 2.2

See Action
2.2

See Action
2.2

See Action
2.2

See Action
2.2

2

1, 2

FWS, AZGFD,
NMDGF, FS, WMAT

134,000

Increasing

25

6,298,000

2

3

32,000

Increasing

25

2,672,000

2

3

640,000

Increasing

25

24,100,000

2

3

1.5

1.6

Conduct Mexican wolf
releases to increase
population size in Mexico
Reduce human-caused
mortality of Mexican wolves
in the U.S.

1.7

Reduce human-caused
mortality of Mexican wolves
in Mexico

1.8

Reduce Mexican wolflivestock conflicts in the U.S.

Actions Needed

CONANP, CNOG,
SAGARPA,
PROFEPA, MFS,
PGR, GN
FWS, AZGFD,
NMDGF, DOW,
MWF, USDA-WS,
MWLC, AZLLB

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SITE-SPECIFIC ACTION i

1.9

RESPONSIBLE
PARTY

ESTIMATED
COST in FY18
(US dollars)

TREND of
COST over
TIME

Reduce Mexican wolflivestock conflicts in the
Mexico

SAGARPA, MFS,
CNOG, CONANP,
CONAFOR

100,000

ESTIMATED
TOTAL COST
ADDRESSES
PRIORITY iii
TIME
(US dollars) ii
THREAT iv
(years)

Increasing

Objective 2: Improve gene diversity and maintain the health of Mexican wolves
Develop and implement an
FWS, AZGFD,
annual plan for Mexican wolf
NMDGF, FS, WMAT,
400,000
Stable
2.1
releases, cross-fostering, and
TESF
translocations in the U.S.
Develop and implement an
SSP, CONANP, MFS,
annual plan for Mexican wolf
SEMARNAT, OVIS,
70,000
Stable
2.2
releases, cross-fostering, and
GM, INECOL, FWS
translocations in Mexico
AZGFD, FWS,
Monitor and manage
NMDGF, MFS,
45,000
Stable
2.3
Mexican wolf genetic health
CONANP, UI, UNM
FWS, AZGFD,
NA (costs
NA (costs
Monitor and manage
NMDGF, MFS, IFT,
included in
included in
2.4
Mexican wolf health
USDA-WS, UNAM1.1 and 1.2) 1.1 and 1.2)
FMVZ
Objective 3: Ensure adequate habitat availability to support viable Mexican wolf populations

25

4,850,000

2

3

16

6,400,000

1

1

8

560,000

1

1, 2

25

1,125,000

2

1

25

NA (costs
included in
1.1 and 1.2)

2

3

2

2

2

2

3.1

Maintain habitat for Mexican
wolves in the U.S.

FWS, AZGFD,
NMDGF, FS, BLM,
NPS, NRCS

NA (costs
included in
1.1, 1.2, and
1.6)

NA (costs
included in
1.1, 1.2, and
1.6)

25

NA (costs
included in
1.1, 1.2, and
1.6)

3.2

Maintain and protect habitat
for Mexican wolves in
Mexico

CONANP, MFS,
UNAM IB

93,000

Decreasing

25

587,000

Actions Needed

32

MEXICAN WOLF RECOVERY PLAN, FIRST REVISION

NOVEMBER 2017

SITE-SPECIFIC ACTION i

RESPONSIBLE
PARTY

ESTIMATED
COST in FY18
(US dollars)

TREND of
COST over
TIME

3.3

Maintain and enhance
connectivity within and
between Mexican wolf
populations

FWS, CONANP,
SCT, AZGFD,
NMDGF, CBP, Local,
State, and Federal
DOT

NA (cost
included in
actions 1.1,
1.2, 6.1)

NA (cost
included in
actions 1.1,
1.2, 6.1)

3.4

Maintain or improve the
status of native prey
populations of Mexican
wolves

AZGFD, NMDGF,
WMAT, IFT,
CONANP, MFS

25,000

ESTIMATED
TOTAL COST
ADDRESSES
PRIORITY iii
TIME
(US dollars) ii
THREAT iv
(years)

Stable

25

NA (costs
included in
actions 1.1,
1.2, 6.1)

2

1

25

625,000

2

3

Objective 4: Maintain the Mexican Wolf SSP captive breeding program to improve the status of wild populations
4.1

Manage the Mexican Wolf
captive breeding population

Various SSP, FWS

2,674,000

Decreasing

Objective 5: Promote Mexican wolf conservation through education and outreach programs
Conduct education and
FWS, AZGFD,
450,000
Decreasing
5.1 outreach on Mexican wolf
NMDGF, WMAT, FS
conservation in the U.S.
Conduct education and
NA (costs
NA (costs
MFS, CONANP
included in
included in
5.2 outreach on Mexican wolf
conservation in Mexico
1.7)
1.7)
Objective 6: Ensure recovery success
Manage the Mexican Wolf
FWS
500,000
Decreasing
6.1 Recovery Program in the
U.S.
Manage the Mexican Wolf
CONANP, MFS,
35,000
Stable
6.2
Recovery Program in Mexico
SEMARNAT
6.3

Coordinate binational
Mexican wolf recovery
efforts

Actions Needed

FWS, CONANP

NA (costs
included in
6.1 and 6.2)

NA (costs
included in
6.1 and 6.2)

25

54,682,000

2

1, 2

25

9,000,000

3

2, 3

25

NA (costs
included in
1.7)

3

2, 3

25

8,500,000

3

1, 2, 3

25

875,000

3

1, 2, 3

25

NA (costs
included in
6.1 and 6.2)

3

1, 2, 3

33

MEXICAN WOLF RECOVERY PLAN, FIRST REVISION

SITE-SPECIFIC ACTION i

6.4

Develop adequate regulations
and management and
monitoring plans to maintain
viable Mexican wolf
populations after delisting
TOTAL COST

NOVEMBER 2017

RESPONSIBLE
PARTY

ESTIMATED
COST in FY18
(US dollars)

TREND of
COST over
TIME

CONANP, FWS,
AZGFD, NMDGF,
WMAT

NA (costs
included in
6.1 and 6.2)

NA (costs
included in
6.1 and 6.2)

7,123,000

ESTIMATED
TOTAL COST
ADDRESSES
PRIORITY iii
TIME
(US dollars) ii
THREAT iv
(years)

5

NA (costs
included in
6.1 and 6.2)

3

1, 2, 3

178,439,000

i

The Recovery Implementation Strategy provides additional detailed, site-specific near-term activities needed to implement the actions identified in this
Recovery Action Table.
ii

Because the estimated costs of some actions may increase or decrease over the duration of the action, the total cost of the action cannot be calculated by
multiplying the cost of the action in Fiscal Year 2018 by the estimated time of the action. Whether the trend of the cost is increasing, decreasing, or stable over
the total duration of the action is indicated in the “Trend of Cost over Time” column; however, the calculation of the total cost estimate of each action is
included in greater detail in the Implementation Schedule Table.

iii

Recovery actions are assigned numerical priorities to highlight the relative contribution they may make toward species recovery (48 FR 43098). Priority 1 –
An action that must be taken to prevent extinction or to prevent the species from declining irreversibly. Priority 2 – An action that must be taken to prevent a
significant decline in species population/habitat quality or some other significant negative impact short of extinction. Priority 3 – All other actions necessary to
provide for full recovery of the species.

iv

Threats numbering system: 1) Loss of gene diversity; 2) Extinction risk/demographic stochasticity; 3) Exceeding threshold mortality rate

Actions Needed

34

MEXICAN WOLF RECOVERY PLAN, FIRST REVISION

NOVEMBER 2017

VII. LITERATURE CITED
Adams, L.G., R.O. Stephenson, B.W. Dale, R.T. Ahgook, D.J. Demma. 2008. Population
dynamics and Harvest Characteristics of Wolves in the Central Books Range, Alaska.
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Allendorf, F. W. and G. H. Luikart. 2007. Conservation and genetics of populations. Malden,
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la Conservación de la Especie: Lobo Gris Mexicano. Mexico, D.F., Mexico. 52 pp.
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Hedrick, P. W., P. S. Miller, E. Geffen, and R. K. Wane. 1997. Genetic evaluation of three
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Martínez-Meyer, E., A. González-Bernal, J. A. Velasco, T. L. Swetnam, Z. Y. GonzálezSaucedo, J. Servín, C. A. López González, N. E. Lara Díaz, C. Aguilar Miguel, C. Chávez
García, and J. K. Oakleaf. 2017. Mexican wolf habitat suitability analysis in historical
range in the Southwestern US and Mexico. Final report, April 2017. 86 pp.
Miller, P.S. 2017. Population viability analysis for the Mexican wolf (Canis lupus baileyi):
Integrating wild and captive populations in a metapopulation risk assessment model for
recovery planning. Prepared for U.S. Fish and Wildlife Service, Albuquerque, New
Mexico.
Parsons, D. 1996. Case study: the Mexican wolf. Pages 101-123 in Herrera, E.A. and L.F.
Huenneke, editors. New Mexico’s natural heritage: biological diversity in the Land of
Enchantment. New Mexico Journal of Science 36.
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Naturalist 132:757-785.

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Secretaría de Medio Ambiente, Recursos Naturales y Pesca (SEMARNAP). 2000. Proyecto de
Recuperación del Lobo Mexicano. Mexico, D.F. 103 pp.
Siminski, P. and E. Spevak. 2017. Population analysis and breeding and transfer plan: Mexican
wolf Species Survival Plan yellow program. Association of Zoos and Aquariums, Silver
Spring, Maryland. 89pp.
Smith, D., D. Stahler, E. Albers, R. McIntyre, M. Metz, J. Irving, R. Raymond, C. Anton, K.
Cassidy-Quimby, and N. Bowersock, 2011. Yellowstone Wolf Project: Annual Report,
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Soulé, M, M. Gilpin, W. Conway, and T. Foose. 1986. The millenium ark: how long a voyage,
how many staterooms, how many passengers? Zoo Biology 5: 101-113.
U.S. Fish and Wildlife Service [USFWS]. 1982. Mexican Wolf Recovery Plan. U.S. Fish and
Wildlife Service, Albuquerque, New Mexico, USA. 103 pp.
U.S. Fish and Wildlife Service [USFWS]. 1996. Reintroduction of the Mexican wolf within its
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Region 2, Albuquerque, New Mexico, USA. Available online at:
http://www.fws.gov/southwest/es/mexicanwolf/documents.shtml.
U.S. Fish and Wildlife Service [USFWS]. 1998. Mexican Wolf Reintroduction Annual Report 1.
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U.S. Fish and Wildlife Service [USFWS 2010]. Mexican Wolf Conservation Assessment.
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Mexican wolf. Albuquerque, New Mexico, USA. Available online at:
https://www.fws.gov/southwest/es/mexicanwolf/pdf/EIS_for_the_Proposed_Revision_to_the
_Regulations_for_the_Nonessential_Experimental_Population_of_the_Mexican_Wolf.pdf.
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Literature Cited

36

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U.S. Fish & Wildlife Service
New Mexico Ecological Services Field Office
Mexican Wolf Recovery Program
2105 Osuna Road, NE
Albuquerque, NM 87113
505/346-2525
www.fws.gov/southwest/
www.fws.gov/southwest/es/mexicanwolf/
U.S. Fish and Wildlife Service
Southwest Regional Office
500 Gold Avenue, SW
Albuquerque, NM 87102
505/248-6920
505/248-6788 Fax
Cover: Mexican Wolf
© Bob Martinson

Rear Cover: Mexican Wolf
USDA Forest Service

November 2017