[Federal Register Volume 80, Number 66 (Tuesday, April 7, 2015)]
[Proposed Rules]
[Pages 18741-18772]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-07766]



[[Page 18741]]

Vol. 80

Tuesday,

No. 66

April 7, 2015

Part III





Department of the Interior





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Fish and Wildlife Service





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50 CFR Part 17





Endangered and Threatened Wildlife and Plants; 12-Month Finding on a 
Petition To List Humboldt Marten as an Endangered or Threatened 
Species; Proposed Rule

Federal Register / Vol. 80 , No. 66 / Tuesday, April 7, 2015 / 
Proposed Rules

[[Page 18742]]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R8-ES-2011-0105; 4500030113]


Endangered and Threatened Wildlife and Plants; 12-Month Finding 
on a Petition To List Humboldt Marten as an Endangered or Threatened 
Species

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Notice of 12-month petition finding.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce a 
12-month finding on a petition to list the previously classified 
subspecies Humboldt marten (Martes americana humboldtensis), or the 
(now-recognized) subspecies of Humboldt marten (Martes caurina 
humboldtensis), or the Humboldt marten distinct population segment 
(DPS) of the Pacific marten (M. caurina) as an endangered or threatened 
species under the Endangered Species Act of 1973, as amended (Act). The 
petition and this finding also address populations of marten from 
coastal Oregon, which recent genetic analyses indicate are likely to be 
the same entity as the current classification of Humboldt marten. We 
recognize a coastal DPS of the Pacific marten (which includes coastal 
Oregon populations of marten and the current classification of Humboldt 
marten) and find that this DPS is not warranted for listing at this 
time. However, we ask the public to submit to us any new information 
that becomes available concerning the stressors that may be impacting 
the coastal DPS of Pacific marten or its habitat at any time.

DATES: The finding announced in this document was made on April 7, 
2015.

ADDRESSES: This finding is available on the Internet at http://www.regulations.gov at Docket Number FWS-R8-ES-2011-0105. Supporting 
documentation we used in preparing this finding is available for public 
inspection, by appointment, during normal business hours at the U.S. 
Fish and Wildlife Service, Arcata Fish and Wildlife Office, 1655 
Heindon Road, Arcata, CA 95521. Please submit any new information, 
materials, comments, or questions concerning this finding to the above 
street address.

FOR FURTHER INFORMATION CONTACT: Bruce Bingham, Field Supervisor, U.S. 
Fish and Wildlife Service, Arcata Fish and Wildlife Office (see 
ADDRESSES); by telephone at 707-822-7201; or by facsimile at 707-822-
8411. If you use a telecommunications device for the deaf (TDD), please 
call the Federal Information Relay Service (FIRS) at 800-877-8339.

SUPPLEMENTARY INFORMATION: 

Acronyms and Abbreviations Used in This Document

    We use many acronyms and abbreviations throughout this 12-month 
finding. To assist the reader, we provide a list of these here for easy 
reference:

Act = Endangered Species Act of 1973, as amended (16 U.S.C. 1531 et 
seq.)
AR = Anticoagulant Rodenticides
BLM = Bureau of Land Management
CBD = Center for Biological Diversity
CDFG = California Department of Fish and Game (see below)
CDFW = California Department of Fish and Wildlife (formerly CDFG)
CDPR = California Department of Parks and Recreation
CESA = California Endangered Species Act
CEQA = California Environmental Quality Act
CFR = Code of Federal Regulations
DPS = Distinct Population Segment
EPIC = Environmental Protection Information Center
Forest Service = U.S. Forest Service
FR = Federal Register
GIS = Geographic Information System
HCP = Habitat Conservation Plan
HMCG = Humboldt Marten Conservation Group
IPCC = Intergovernmental Panel on Climate Change
IUCN = International Union for Conservation of Nature
LANDFIRE = Landscape Fire and Resource Management Planning Tools 
Project
LRMP = Land and Resource Management Plan
MDL = Multi-District Litigation
MOU = Memorandum of Understanding
MTBS = Monitoring Trends in Burn Severity
NMFS = National Marine Fisheries Service
NWFP = Northwest Forest Plan
OAR = Oregon Administrative Rules
ODF = Oregon Department of Forestry
RMP = Resource Management Plan
Service = U.S. Fish and Wildlife Service
SPR = Significant Portion of [a Species'] Range
USDA = U.S. Department of Agriculture

Background

    Section 4(b)(3)(B) of the Act (16 U.S.C. 1531 et seq.) requires 
that, for any petition to revise the Federal Lists of Endangered and 
Threatened Wildlife and Plants that contains substantial scientific or 
commercial information suggesting that listing a species may be 
warranted, we make a finding within 12 months of the date of receipt of 
the petition. In this finding, we will determine that the petitioned 
action is: (1) Not warranted, (2) warranted, or (3) warranted, but the 
immediate proposal of a regulation implementing the petitioned action 
is precluded by other pending proposals to determine whether species 
are endangered or threatened, and expeditious progress is being made to 
add or remove qualified species from the Federal Lists of Endangered 
and Threatened Wildlife and Plants (``warranted but precluded''). 
Section 4(b)(3)(C) of the Act requires that we treat a petition for 
which the requested action is found to be warranted but precluded as 
though resubmitted on the date of such finding, that is, requiring a 
subsequent finding to be made within 12 months. We must publish these 
12-month findings in the Federal Register.

Previous Federal Actions

    On September 28, 2010, we received a petition dated September 28, 
2010, from the Center for Biological Diversity (CBD) and the 
Environmental Protection Information Center (EPIC), requesting that we 
consider for listing the (then-classified) subspecies Humboldt marten 
(Martes americana humboldtensis), or the (now-recognized) subspecies 
Humboldt marten (M. caurina humboldtensis), or the Humboldt marten DPS 
of the Pacific marten (M. caurina). The petitioners further stipulated 
that, based on recent genetic analyses indicating that populations of 
marten from coastal Oregon (considered members of M. a. caurina) are 
more closely related to M. a. humboldtensis than to M. a. caurina in 
the Cascades of Oregon (citing Dawson 2008, Slauson et al. 2009a), the 
range of the subspecies or DPS of the Humboldt marten should be 
expanded to include coastal Oregon populations of martens. In a letter 
to the petitioners dated October 22, 2010, we responded that we 
reviewed the information presented in the petition and determined that 
issuing an emergency regulation temporarily listing the species under 
section 4(b)(7) of the Act was not warranted.
    On January 12, 2012, we published in the Federal Register a 90-day 
finding (77 FR 1900) that the petition presented substantial 
information indicating that listing may be warranted and that initiated 
a status review. For purposes of the 90-day finding, the common name 
Humboldt marten referred to the then-classified American marten (M. 
americana) populations in coastal northern California and coastal 
Oregon.
    On June 23, 2014, we published a scoping notice in the Federal 
Register (79 FR 35509) that summarized the uncertainty regarding the 
taxonomic classification of the subspecies (based on current genetics 
information) and indicated our intent to conduct an evaluation (for the 
12-month finding) of

[[Page 18743]]

a potential DPS of martens in coastal northern California and coastal 
Oregon relative to the full species classification level.
    According to section 3(16) of the Act, we may consider for listing 
any of three categories of vertebrate animals: A species, subspecies, 
or DPS (see the Service's 1996 DPS Policy at 61 FR 4722). We refer to 
each of these categories as a potential ``listable entity.'' We 
evaluated three possible listable entities for this 12-month finding 
based upon the best available published and unpublished information for 
martens in coastal northern California and coastal Oregon (for further 
details, please see the Current Taxonomic Description and Listable 
Entity Evaluation and Distinct Population Segment Analysis sections, 
below):
     Subspecies Humboldt marten (Martes americana 
humboldtensis): This entity was considered not reasonable for 
evaluation because its species-level name is no longer considered 
valid. Specifically, Dawson and Cook (2012, entire) split the then-
classified American marten (M. americana) to recognize the Pacific 
marten (M. caurina) for all martens occurring west of the Rocky 
Mountain crest.
     Subspecies Humboldt marten (Martes caurina humboldtensis): 
This entity was considered not reasonable for evaluation because its 
description is (currently) specifically linked with the extant 
population that resides in coastal northern California and does not 
include the coastal Oregon populations, which the best available 
genetics data indicate are likely the same entity.
     DPS of the Pacific marten (Martes caurina): We considered 
it reasonable that a DPS of the Pacific marten constitute the listable 
entity for our status review based on our evaluations of the best 
scientific and commercial data currently available (including 
unpublished genetics information), and our consideration of the 
Service's February 7, 1996, Policy Regarding the Recognition of 
Distinct Vertebrate Population Segments Under the Endangered Species 
Act (DPS Policy; 61 FR 4722). As such, we considered in the scoping 
notice (79 FR 35509; June 23, 2014) that the DPS include the currently 
recognized M. caurina humboldtensis (i.e., Humboldt marten) and the 
coastal populations of M. caurina caurina in Oregon (i.e., Oregon Coast 
Range group). We solicited information regarding our consideration of 
the coastal northern California and coastal Oregon populations of 
Pacific marten as a single listable entity. See Listable Entity 
Evaluation and Distinct Population Segment Analysis, below, for 
additional discussion related to our decision that a coastal DPS of the 
Pacific marten (hereafter referred to as ``coastal marten'') 
constitutes the listable entity for this status review.
    This notice constitutes the 12-month finding on the September 28, 
2010, petition to list the (then-classified) subspecies Humboldt marten 
(Martes americana humboldtensis), or the (now-recognized) subspecies 
Humboldt marten (M. caurina humboldtensis), or the Humboldt marten DPS 
of the Pacific marten (M. caurina) as an endangered or threatened 
species.
    This finding is based upon the Species Report titled ``Coastal 
Oregon and Northern Coastal California populations of the Pacific 
marten (Martes caurina)'' (Service, 2015) (Species Report), a 
scientific analysis of available information prepared by a team of 
Service biologists from the Service's Arcata Fish and Wildlife Office, 
Oregon Fish and Wildlife Office, Pacific Southwest Regional Office, 
Pacific Regional Office, and National Headquarters Office. The purpose 
of the Species Report is to provide the best available scientific and 
commercial information about the species so that we can evaluate 
whether or not the species warrants protection under the Act. In it, we 
compiled the best scientific and commercial data available concerning 
the status of the coastal Oregon and northern coastal California 
populations of Pacific marten, including past, present, and future 
threats to these populations. As such, the Species Report, including 
the appendix, provides the scientific basis that informs our regulatory 
decision in this document, which involves the further application of 
standards within the Act and its regulations and policies. The Species 
Report can be found on the Internet at http://www.regulations.gov, 
Docket No. FWS-R8-ES-2011-0105.

Current Taxonomic Description

    The American marten (Martes americana) was originally described as 
a single species by Turton (1806, entire), based on specimens from 
eastern North America. In 1890, Merriam (1890, entire) considered a new 
species, Mustela [=Martes] caurina, to be those martens found west of 
the Rocky Mountains. In 1926, the Humboldt [Pine] marten (M. c. 
humboldtensis) was described as a subspecies of Martes caurina 
(Grinnell and Dixon 1926, entire); historically, this subspecies was 
distributed throughout the coastal, fog-influenced coniferous forests 
of northern California from northwestern Sonoma County north to the 
Oregon border (Grinnell and Dixon 1926, entire). In 1953, Wright (1953, 
entire) described one species, the American marten (M. americana), 
which included as subspecies both the Humboldt [Pine] marten subspecies 
(M. a. humboldtensis), and the former western marten species (M. 
caurina), classified as M. a. caurina.
    As noted above, at the time of our 90-day finding (77 FR 1900; 
January 12, 2012), the Humboldt marten was classified as Martes 
americana humboldtensis. Subsequently, Dawson and Cook (2012, entire) 
split the American marten, recognizing the Pacific marten (M. caurina) 
for all martens occurring west of the Rocky Mountain crest, based on 
genetic and morphological differences. Currently, the classification of 
the Humboldt marten in coastal northern California is M. c. 
humboldtensis, and the marten populations occurring in adjacent coastal 
Oregon are M. c. caurina. In addition, as currently recognized, 
populations of martens in the Oregon Cascades northward through the 
State of Washington and into British Columbia, Canada, are also M. c. 
caurina.
    Ongoing genetic research indicates uncertainty in the currently 
accepted Pacific marten subspecies delineations in California and 
Oregon. Specifically, the best available data indicate that the Martes 
caurina humboldtensis population in coastal northern California 
(Humboldt, Siskiyou, and Del Norte Counties) and the two known M. c. 
caurina populations in coastal Oregon (Curry, Coos, coastal portion of 
Douglas, coastal portion of Lane, Lincoln, and Tillamook Counties) are 
likely a single evolutionary unit (clade) (Slauson et al. 2009a, p. 
1,340; Schwartz and Slauson 2015, pers. comm.) (as noted in the scoping 
notice that published in the Federal Register on June 23, 2014 (79 FR 
35509), and was made available for review at http://www.regulations.gov, Docket No. FWS-R8-ES-2014-0023). Although 
questions regarding the taxonomy of marten subspecies in northern 
California and Oregon are not new (i.e., both the petition we received 
(CBD and EPIC 2010) and our 90-day finding (January 12, 2012; 77 FR 
1900) identified ongoing genetic research and taxonomic uncertainty), 
the best available information indicate that the original designation 
of two separate marten subspecies occurring in coastal northern 
California and coastal Oregon is likely invalid (Schwartz and Slauson 
2015, pers. comm.).

[[Page 18744]]

Listable Entity Evaluation and Distinct Population Segment Analysis

    Based on the September 28, 2010, petition, and information received 
both prior and subsequent to our June 23, 2014, scoping notice 
regarding the listable entity, we considered whether the potential 
coastal DPS of Pacific marten meets the definition of a DPS as 
described in the Service's DPS Policy (61 FR 4722; February 7, 1996).
    Section 3(16) of the Act defines the term ``species'' to include 
``. . . any subspecies of fish or wildlife or plants, and any distinct 
population segment of any species of vertebrate fish or wildlife which 
interbreeds when mature.'' We have always understood the phrase 
``interbreeds when mature'' to mean that a DPS must consist of members 
of the same species or subspecies in the wild that would be 
biologically capable of interbreeding if given the opportunity, but all 
members need not actually interbreed with each other. A DPS is a subset 
of a species or subspecies, and cannot consist of members of a 
different species or subspecies. The ``biological species concept'' 
defines species according to a group of organisms, their actual or 
potential ability to interbreed, and their relative reproductive 
isolation from other organisms. This concept is a widely accepted 
approach to defining species. The Act's use of the phrase ``interbreeds 
when mature'' reflects this understanding. Use of this phrase with 
respect to a DPS is simply intended to mean that a DPS must be 
comprised of members of the same species or subspecies. As long as this 
requirement is met, a DPS may include multiple populations of 
vertebrate organisms even if they may not actually interbreed with each 
other. For example, a DPS may consist of multiple populations of a fish 
species separated into different drainages. While these populations may 
not actually interbreed with each other, their members are biologically 
capable of interbreeding.
    The National Marine Fisheries Service (NMFS) and the Service 
published a joint Policy Regarding the Recognition of Distinct 
Vertebrate Population Segments Under the Endangered Species Act (DPS 
Policy on February 7, 1996 (61 FR 4722). According to the DPS Policy, 
two elements must be satisfied in order for a population segment to 
qualify as a possible DPS: discreteness and significance. If the 
population segment qualifies as a DPS, the conservation status of that 
DPS is then evaluated to determine whether it is endangered or 
threatened.
    A population segment of a vertebrate species may be considered 
discrete if it satisfies either one of the following conditions: (1) It 
is markedly separated from other populations of the same taxon as a 
consequence of physical, physiological, ecological, or behavioral 
factors; or (2) it is delimited by international governmental 
boundaries within which differences in control of exploitation, 
management of habitat, conservation status, or regulatory mechanisms 
exist that are significant in light of section 4(a)(1)(D) of the Act.
    If a population is found to be discrete, then it is evaluated for 
significance under the DPS Policy on the basis of its importance to the 
taxon to which it belongs. This consideration may include, but is not 
limited to, the following: (1) Persistence of the discrete population 
segment in an ecological setting unusual or unique to the taxon; (2) 
evidence that loss of the discrete population segment would result in a 
significant gap in the range of a taxon; (3) evidence that the 
population represents the only surviving natural occurrence of a taxon 
that may be more abundant elsewhere as an introduced population outside 
of its historical range; or (4) evidence that the population differs 
markedly from other populations of the species in its genetic 
characteristics.
    If a population segment is both discrete and significant (i.e., it 
qualifies as a potential DPS), its evaluation for endangered or 
threatened status is based on the Act's definitions of those terms and 
a review of the factors listed in section 4(a) of the Act. According to 
our DPS Policy, it may be appropriate to assign different listing 
classifications to different DPSs of the same vertebrate taxon.
    We were petitioned to list collectively two groups of the Pacific 
marten (two populations in Oregon and one in California) that are 
currently recognized as belonging to two separate subspecies (as 
described above). To ensure that we evaluated the most accurate 
listable entity based on the best scientific and commercial data 
currently available (including unpublished genetics information), we 
published a scoping notice in the Federal Register on June 23, 2014 (79 
FR 35509), notifying the public that we considered it reasonable that a 
coastal DPS of the Pacific marten constitute the listable entity for 
our status review.
    We received eight comment letters from six entities in response to 
our June 23, 2014, scoping notice. Four entities agreed with our 
proposed DPS, one was silent, and one disagreed with our evaluation of 
a coastal DPS of the Pacific marten as the listable entity; two 
entities commented twice reiterating their same positions. The 
commenter who disagreed with the proposed coastal DPS of the Pacific 
marten as the listable entity believed more information, including 
genetics, would be required and that the entity we proposed would not 
be a valid DPS according to Service criteria. Following publication of 
the scoping notice in the Federal Register, we received more genetics 
information (Schwartz and Slauson 2015, pers. comm.) that supports our 
consideration of a coastal DPS of the Pacific marten.
    After taking into consideration the comments received and 
conducting further evaluation of the best available scientific and 
commercial information (including additional genetics information), we 
confirm here that this DPS is a listable entity, including the 
currently recognized Martes caurina humboldtensis (i.e., Humboldt 
marten) and the coastal populations of M. caurina caurina in Oregon 
(i.e., Oregon Coast Range group). This entity is reasonable given:
    (1) The best available data (e.g., new genetics information, 
similar habitat usage) suggest that the coastal northern California 
marten population and the coastal Oregon marten populations represent a 
single evolutionary entity as opposed to two separate entities 
(Schwartz et al., In prep.). In particular, Schwartz et al. (In prep.) 
has provided substantive information (with both mitochondrial and 
nuclear DNA evaluations) that the marten populations occurring in 
coastal northern California and coastal Oregon are unique and more 
closely related to each other than to other groups/populations of 
Pacific martens, to the extent that they are diagnosably distinct from 
all other Pacific martens.
    (2) Existing genetics information (Slauson et al. 2009a, entire) 
suggests that subspecies-level taxonomy of M. c. humboldtensis, M. c. 
caurina, and possibly other subspecies of the Pacific marten as 
currently classified may be inaccurate.
    (3) The DPS Policy (February 7, 1996; 61 FR 4722) states that the 
population segment under consideration must be evaluated for 
discreteness and significance in relation to the remainder of the taxon 
to which it belongs. Ordinarily, in the present case we would evaluate 
the marten populations relative to the subspecies to which they belong, 
but the populations in question currently represent two separate 
subspecies and there is uncertainty as to the legitimacy of those 
subspecies classifications, rendering such an evaluation invalid.

[[Page 18745]]

    (4) Uncertainty in the subspecies-level taxonomy of Pacific marten 
logically necessitates that we elevate our evaluation of the DPS 
relative to the Pacific marten at the full species level. In other 
words, we apply the criteria for evaluating a coastal DPS of the 
Pacific marten relative to the full species Pacific marten (Martes 
caurina) as a whole.
    (5) The DPS Policy (February 7, 1996; 61 FR 4722) states that ``In 
all cases, the organisms in a population are members of a single 
species or lesser taxon.'' Therefore, given (1) through (4) above, an 
evaluation at the species level is appropriate. Consequently, for 
purposes of this Finding, below we evaluate the Pacific marten 
populations that occur in coastal Oregon and coastal northern 
California under our DPS Policy.
    For this 12-month finding and DPS analysis of the Pacific marten 
populations that occur in coastal Oregon and coastal northern 
California, we reviewed and evaluated all available published and 
unpublished information, including numerous publications, reports, and 
other data submitted by the public. Marten distribution in coastal 
northern California and coastal Oregon is discussed in detail in the 
``Species Distribution'' section of the Species Report titled ``Coastal 
Oregon and Northern Coastal California populations of the Pacific 
marten (Martes caurina)'' (Service 2015, pp. 28-32), which is available 
on the Internet at http://www.regulations.gov, Docket No. FWS-R8-ES-
2011-0105.
Discreteness
    Under the DPS Policy, a population segment of a vertebrate taxon 
may be considered discrete if it satisfies either one of the following 
conditions:
    (1) It is markedly separated from other populations of the same 
taxon as a consequence of physical, physiological, ecological, or 
behavioral factors. Quantitative measures of genetic or morphological 
discontinuity may provide evidence of this separation.
    (2) It is delimited by international governmental boundaries within 
which differences in control of exploitation, management of habitat, 
conservation status, or regulatory mechanisms exist that are 
significant in light of section 4(a)(1)(D) of the Act. As the marten 
populations in question here do not transcend an international 
boundary, this criterion does not apply.
    As described below, the Pacific marten populations that occur in 
coastal Oregon and coastal northern California are markedly separated 
from other Pacific marten populations by geographical isolation (i.e., 
separated by areas of unsuitable habitat), and marked genetic 
differences between those coastal populations (coastal Oregon and 
coastal northern California) and other populations of Pacific marten 
are evidence of this long-standing separation. The extant population in 
coastal northern California is separated from the Sierra marten 
subspecies (Martes caurina sierrae) by unsuitable habitat to the east 
in the Klamath River canyon. The coastal central Oregon extant 
population is separated from Pacific marten populations to the east (in 
the Oregon Cascade Mountains) primarily by unsuitable habitat within 
the Willamette Valley. Although some suitable habitat occurs between 
the coastal southern Oregon extant population area and the southern 
Cascades population of Pacific martens to the east, the distance to 
large blocks of suitable habitat in the southern Cascade Mountains far 
exceeds the mean maximum dispersal distance for martens (see discussion 
below). Additionally, martens that occur in coastal Oregon and coastal 
northern California occur in areas without significant, persistent 
snowpack (Slauson 2003, p. 66; Slauson et al., In prep.). Mountain 
ranges to the east that have both unsuitable marten habitat and are 
covered by significant, persistent snowpack stand between the coastal 
Oregon and coastal northern California populations of Pacific martens 
and other Pacific marten populations (e.g., separation of Humboldt and 
Sierra Nevada populations), thereby effectively isolating the coastal 
marten populations from other Pacific martens. East-west movements that 
would potentially connect Pacific marten populations in coastal Oregon 
and coastal northern California with inland Pacific marten populations 
are likely rare because:
    (1) Most juvenile marten dispersal distances (that are published in 
literature) in both logged and unlogged forests range from less than or 
equal to 5 km (3.1 mi) (Broquet et al. 2006, p. 1,694) to approximately 
15 km (9.3 mi) (Phillips 1994, pp. 93-94; Pauli et al. 2012, p. 393). 
The distance between the coastal Oregon and coastal northern California 
populations of Pacific martens and other Pacific marten populations to 
the east exceeds the likely maximum dispersal distance.
    (2) Pacific martens within the three extant populations in coastal 
Oregon and coastal northern California likely only need to disperse 
short distances to establish a home range because there are typically 
sufficient amounts of unoccupied suitable habitat available within 
their natal area.
    (3) Large patches of unsuitable habitat on the eastern edge of the 
historical range in this region would likely deter juvenile martens 
from moving east. As described below in the section Summary of Species 
Information, the coastal Oregon and coastal northern California 
populations of Pacific martens require a dense shrub understory 
comprised of shade-tolerant shrub species within the conifer-dominated 
overstory that they occupy (Zielinski et al. 2001, p. 485; Slauson et 
al. 2007, p. 464), and in coastal Oregon and coastal northern 
California, this dense shrub layer generally does not occur outside of 
the coastal fog-influenced areas. Thus, martens in coastal northern 
California and coastal Oregon are functionally isolated from other 
marten populations by their dependence on the dense shrub layer found 
in the coastal coniferous forests of this region.
    The coastal Oregon and coastal northern California populations of 
Pacific martens are also markedly separated from other populations of 
the Pacific marten as evidenced by quantitative measures of genetic 
discontinuity. The Humboldt marten was historically distributed 
throughout the coastal coniferous forests of northern California from 
northwestern Sonoma County northward to the Oregon border (Grinnell et 
al. 1937, pp. 207-210). Recent phylogenetic analyses using 
mitochondrial DNA (mtDNA) support the distinctiveness of the Humboldt 
marten subspecies, based on the presence of distinct haplotypes shared 
by historical museum specimens and martens currently occupying portions 
of the historical range in northern coastal California (Slauson et al. 
2009a, entire). Marten populations in coastal Oregon, which were 
historically described as M. c. caurina, also share these haplotypes, 
leading Slauson et al. (2009a, pp. 1338-1339) to suggest that martens 
in the Coast Range of Oregon may also be M. c. humboldtensis. 
Furthermore, preliminary results of a subspecific genetic evaluation of 
the Pacific marten by Schwartz et al. (In prep.)--using nuclear DNA 
(nDNA) and samples from substantially more martens than used by Slauson 
et al. (2009a)--demonstrate that the coastal Oregon and coastal 
northern California populations of Pacific martens are clearly 
distinguishable from other populations of Pacific marten on the basis 
of their genetic characteristics. Schwartz et al. (In prep.) indicate 
that coastal Oregon and northern coastal California marten populations 
represent a single evolutionary clade, calling into

[[Page 18746]]

question the separation of the original subspecies range boundaries 
(i.e., M. c. humboldtensis in northern coastal California and M. c. 
caurina in coastal Oregon) at the California-Oregon border. Although 
some low degree of introgression indicates occasional past movement of 
individuals between coastal and inland populations, the evidence 
suggests this was an infrequent occurrence (Schwartz et al., In prep.); 
thus, the coastal Oregon and coastal northern California populations of 
Pacific martens are effectively genetically discrete from other 
populations of Pacific marten.
    In summary, the best available information indicates that Pacific 
marten populations in coastal Oregon and coastal northern California 
are geographically isolated and genetically discrete from all other 
populations of the Pacific marten. Therefore, the marked separation 
condition for discreteness under our DPS Policy is met.
Significance
    If a population segment is considered discrete under one or more of 
the conditions described in the Service's DPS Policy, its biological 
and ecological significance will be considered in light of 
Congressional guidance that the authority to list DPSs be used 
``sparingly'' (see Senate Report 151, 96th Congress, 1st Session) while 
encouraging the conservation of genetic diversity. In making this 
determination, we consider available scientific evidence of the DPS's 
importance to the taxon to which it belongs.
    Because precise circumstances are likely to vary considerably from 
case to case, the DPS Policy does not describe all the classes of 
information that might be used in determining the biological and 
ecological importance of a discrete population. However, the DPS Policy 
describes four possible classes of information that provide evidence of 
a population segment's biological and ecological importance 
(significance) to the taxon to which it belongs. This consideration of 
the population segment's significance may include, but is not limited 
to, the following:
    (1) Persistence of the discrete population segment in an ecological 
setting unusual or unique to the taxon;
    (2) Evidence that loss of the discrete population segment would 
result in a significant gap in the range of a taxon;
    (3) Evidence that the discrete population segment represents the 
only surviving natural occurrence of a taxon that may be more abundant 
elsewhere as an introduced population outside its historical range; or
    (4) Evidence that the discrete population segment differs markedly 
from other populations of the species in its genetic characteristics.
    To be considered significant, a population segment needs to satisfy 
only one of these conditions. Other classes of information that might 
bear on the biological and ecological importance of a discrete 
population segment may also be used as appropriate, to provide evidence 
for significance, as described in the DPS Policy (61 FR 4722; February 
7, 1996). At least two of the significance criteria are met for the 
marten populations in coastal Oregon and coastal northern California. 
First, we find that populations of Pacific martens in coastal Oregon 
and coastal northern California differ markedly from other populations 
of the Pacific marten species in their genetic characteristics. As 
described above under ``Discreteness,'' the coastal Oregon and coastal 
northern California populations of Pacific martens are genetically 
distinct from all other populations of Pacific martens (Schwartz et 
al., In prep.). As a result, loss of the marten populations from 
coastal Oregon and coastal northern California would result in a 
reduction in Pacific marten genetic diversity. Second, we find that the 
loss of martens from coastal Oregon and coastal northern California 
would result in a significant gap in the range for the Pacific marten. 
The coastal populations of martens in California and Oregon represent 
the only coastal populations of Pacific martens in these States and 
inhabit a habitat association unique from other non-coastal marten 
populations--that is, areas consisting of occasional, non-persistent 
snowpack (below 914 meters (m) (3,000 feet (ft)) with a mesic, shade-
tolerant shrub layer (understory) within coastal coniferous forest 
habitat (see ``Life History'' section of the Species Report). The 
requirement of this dense (greater than 70 percent cover), shrubby 
understory is particularly unusual for martens, and is a unique habitat 
association not described elsewhere in the distribution of either 
Pacific martens or American martens in North America (Slauson et al., 
In prep.(a)). The coastal Oregon and coastal northern California 
populations of Pacific martens are also the only martens known to 
utilize coastal serpentine habitat and dune forest habitat distributed 
on coastal terraces. These genetic differences and the evidence that a 
significant gap in the range of the taxon would result from the loss of 
the discrete population segment both individually satisfy the 
significance criterion of the DPS Policy. Therefore, under the 
Service's DPS Policy, we find that the populations of Pacific martens 
in coastal Oregon and coastal northern California are significant to 
the taxon to which they belong.
Conclusion of DPS Analysis Regarding Pacific Martens in Coastal Oregon 
and Coastal Northern California
    As stated above under Current Taxonomic Description, the best 
available scientific and commercial information suggests that the 
coastal Oregon populations of Pacific marten (Martes caurina caurina) 
are likely the same entity as the currently classified Humboldt marten 
(M. c. humboldtensis). We find that the coastal Oregon and coastal 
northern California populations of Pacific martens collectively 
constitute a valid DPS under the Service's DPS Policy because this 
population segment is both discrete and significant to the taxon to 
which it belongs. We therefore consider the coastal Oregon and coastal 
northern California populations of Pacific martens collectively as the 
``coastal DPS of the Pacific marten,'' which constitutes the listable 
entity for this status review. Throughout this document when we use the 
term ``coastal marten,'' we are using this term as shorthand for the 
coastal DPS of the Pacific marten.

Summary of Species Information

    A thorough review of the taxonomy, life history, biophysical 
environment, habitat use, distributions, and population abundance/
trends of the coastal DPS of Pacific marten is presented in the Species 
Report (Service 2015, pp. 1-40) available on the Internet at http://www.regulations.gov, Docket No. FWS-R8-ES-2011-0105). A summary of this 
information is presented below. We used data specific to coastal marten 
populations when they were available; when such information was 
lacking, we relied on information regarding North American martens in 
general (American or Pacific martens), and have made these distinctions 
in the text that follows.
Life History
    Two species of marten, divided into 14 total subspecies, inhabit 
North America. Collectively, North American martens are characterized 
by the long and narrow body type typical of the mustelid family 
(Mustelidae; e.g., weasels, minks, otters and fishers), overall brown 
pelage (fur) with distinctive coloration on the throat and upper chest 
that varies from orange to yellow to cream, large and distinctly

[[Page 18747]]

triangular ears, and a bushy tail that is proportionally equivalent to 
about 75 percent of the body length (Clark et al. 1987, p. 2; Powell et 
al. 2003, p. 636).
    Marten activity patterns coincide with their prey species 
availability. Specifically, martens are active year-round and 
seasonally adjust their activity patterns to synchronize with those of 
their key prey species (Zielinski et al. 1983, pp. 387-388). Overall, 
the diet of North American marten species is dominated by mammals, but 
birds, insects, and fruits are seasonally important (Martin 1994, pp. 
298-301). Diet analysis for the coastal marten is currently limited to 
scats collected from the coastal northern California population during 
summer and fall, and includes mammals, berries, birds, and reptiles 
(Slauson and Zielinski, In prep.). Sciurid (members of the squirrel 
family) and cricetid rodents (i.e., New World rats and mice) dominate 
the coastal marten's diet, with the most frequent prey species being 
chipmunks (Tamias spp.) and red-backed voles (Myodes californicus), 
and, to a lesser extent, Douglas squirrels (Tamiasciurus douglasii) and 
flying squirrels (Glaucomys sabrinus) (Slauson and Zielinski, In 
prep.).
    Information on coastal marten reproduction and survivorship is 
lacking; therefore our analysis is based on knowledge of North American 
martens in general, which are polygamous mammals. Female martens mate 
no sooner than 15 months of age and first litters are produced no 
sooner than 24 months of age (Strickland et al. 1982, p. 601). Mating 
occurs from late June to early August (Markley and Bassett 1942, pp. 
606-607), and females give birth in March and April (Strickland et al. 
1982, p. 602). Female martens are capable of producing from one to five 
kits per litter, but the modal average is two to three (Strickland and 
Douglas 1987, p. 602; Mead 1994, p. 410). Information is not available 
on the average number of young raised to weaning, the average number of 
young recruited into the population per female, or the effects of 
annual variation in environmental conditions and prey populations on 
kit survival. Regarding longevity, captive Pacific martens are known to 
reach 15 years of age (Clark et al. 1987, p. 3); however, data from 
American marten individuals in the wild in the Algonquin Region of 
Ontario, Canada, indicate that 10 percent (of 2,076 females trapped) 
were more than 5 years old (Strickland and Douglas 1987, p. 535). 
Finally, age structure of coastal martens has not been studied, 
although the best available information from an untrapped population of 
Pacific martens in the Sierra Nevada mountains indicates relatively 
consistent proportions of yearling and adult age classes (Slauson et 
al., In prep.(a)).
    Juvenile dispersal of the American marten is generally thought to 
occur as early as August, although fall, winter, and spring (the year 
after birth) dispersal periods have been reported (Clark and Campbell 
1976, p. 294; Slough 1989, p. 993). Juvenile dispersal in coastal 
northern California and Sierra Nevada martens has been observed to 
occur as early as August and continues at least until the following 
summer season (Slauson and Zielinski 2014, unpubl. data). Information 
is not available regarding the timing of juvenile dispersal for coastal 
martens in Oregon. Pauli et al. (2012, p. 393) found that Pacific and 
American martens exhibit similar dispersal distances, averaging 15.5 km 
(9 mi). Most studies find that the majority of juvenile martens 
disperse relatively short distances to establish home ranges, ranging 
from less than or equal to 5 km (3.1 mi) (Broquet et al. 2006, p. 
1,694) to approximately 15 km (9.3 mi) (Phillips 1994, pp. 9394; Pauli 
et al. 2012, p. 393). However, Broquet et al. (2006, p. 1695) also 
describe juvenile martens as capable of covering long distances during 
dispersal, up to 82 km (50 mi) in their study. Other researchers have 
reported instances of dispersal movements by martens ranging from 40 to 
80 km (25 to 50 mi) (Thompson and Colgan 1987, pp. 831-832; Fecske and 
Jenks 2002, p. 310), up to 149 km (93 mi) or even 160 km (100 mi) in 
distance (Slough 1989, p. 993; Kyle and Strobeck 2003, p. 61). Based on 
minimal genetic structuring of marten populations in a heavily 
harvested forest landscape, Kyle and Strobeck (2003, pp. 60-61) 
suggested that habitat fragmentation may not necessarily impede marten 
movement to the degree formerly understood. However, Kyle and Strobeck 
(2003, p. 65) also caution that smaller scale disturbances may still 
act as partial barriers to marten gene flow. Johnson (2008, pp. 33-36) 
found that juvenile martens traveled slower, shorter distances, and 
suffered twice the mortality risk in logged versus unlogged landscapes. 
Therefore, the best available information suggest that landscape 
condition (e.g., the spatial distribution of unlogged and logged 
stands) has important effects on dispersal dynamics, affecting both the 
distance dispersers can travel and the success rate they have in 
establishing home ranges and surviving to adulthood.
    Intraguild predation and interspecific competition occurs naturally 
within the range of the coastal DPS of Pacific marten. Intraguild 
predation refers to killing and eating of potential competitors that 
utilize the same prey resources. Interspecific competition is a form of 
competition in which individuals of a different species compete for the 
same resource in an ecosystem (as opposed to intraspecific competition 
that involves organisms of the same species). Martens are susceptible 
to predation by larger mammalian and avian predators, typically 
habitat-generalist species, including coyote (Canis latrans), red fox 
(Vulpes vulpes), bobcat (Felis rufus), fishers (Pekania pennanti), and 
great horned owl (Bubo virginianus) (Thompson 1994, p. 276; Lindstrom 
et al. 1995, entire; Bull and Heater 2001, p. 4; McCann et al. 2010, p. 
11). Marten predators may vary depending on the quality of the habitat. 
For example, American marten populations in highly altered forest 
landscapes show higher rates of predation by habitat generalist 
carnivores (and lower annual survival rates) than those in less-altered 
forest landscapes (Thompson 1994, p. 278)). Because marten populations 
are strongly influenced by adult and juvenile survivorship (Buskirk et 
al. 2012, p. 89), predation of martens can have a meaningful effect on 
abundance and population growth rates. Additional discussion on 
predation as a stressor on the coastal marten is provided below in 
Summary of Information Pertaining to the Five Factors.
Habitat Description
    The preferred habitat type for the coastal DPS of Pacific marten 
occurs in some of the most productive forests in the world. In 
unmanaged, late-seral stages, these forests are typically composed of 
long-lived, large trees, with multi-layered canopy structure, 
substantial large woody debris (standing and downed), and abundant 
ferns, herbs, and shrubs on the forest floor (Sawyer et al. 2000, 
entire; Chappell et al. 2001, entire; Sawyer 2007, entire; DellaSala et 
al. 2011, entire). The forests are largely coniferous and typically 
dominated by coast Douglas-fir (Pseudotsuga menziesii menziesii), 
western hemlock (Tsuga heterophylla), and Sitka spruce (Picea 
sitchensis) in Oregon, and redwood (Sequoia sempervirens) and coast 
Douglas-fir in California (Ricketts et al. 1999, entire; Sawyer 2007, 
entire). Higher elevation areas also include sub-dominant conifers such 
as western red cedar (Thuja plicata), Port Orford-cedar (Chamaecyparis 
lawsoniana), grand fir (Abies grandis), sugar pine (Pinus lambertiana), 
and white fir (Abies

[[Page 18748]]

concolor) (Chappell et al. 2001, entire; Sawyer 2007, entire). 
Hardwood-dominated stands are uncommon, although hardwood species such 
as tanoak (Notholithocarpus densiflorus), golden chinquapin 
(Chrysolepis chrysophylla), and Pacific madrone (Arbutus menziesii) are 
common canopy subdominants. Red alder (Alnus rubra) can occur as an 
early successional overstory dominant in the uplands in some near-coast 
locations or post-logging sites. Riparian forests are dominated by 
broadleaf species such as red alder, black cottonwood (Populus 
trichocarpa), bigleaf maple (Acer macrophyllum), and mesic shrub 
species such as vine maple (A. circinatum).
    A dense understory of shrubs and herbaceous plants are a key 
habitat requirement for the coastal marten (see ``Habitat Use'' section 
of the Species Report (Service 2015, pp. 18-27)). Species presence and 
dominance is shaped largely by the combination of soil nutrients and 
moisture, with herbaceous species such as sword fern (Polystichum 
munitum) dominating on nitrogen rich or very moist sites, and evergreen 
shrubs such as Pacific rhododendron (Rhododendron macrophyllum) and 
salal or wintergreen (Gaultheria sp.) dominating on nutrient poor or 
drier sites (Chappell and Kagan 2001, entire). Other dominant or co-
dominant understory shrub species include evergreen huckleberry 
(Vaccinium ovatum), salmonberry (Rubus spectabilis), red huckleberry 
(Vaccinium parvifolium), and in serpentine habitats (see description 
below) dwarf tanbark (Notholithocarpus densiflorus var. echinoides) and 
huckleberry oak (Quercus vaccinifolia) (Jimerson et al. 1996, pp. A13-
A15; Sawyer et al. 2000, entire; Chappell et al. 2001, entire). Many of 
the dominant shrub species are adapted to fire by having lignotubers, 
which are basal swellings at the interface between the roots and shoots 
usually just below the soil surface, allowing these species to quickly 
sprout after fire kills the shoots and thus maintain site dominance 
(Agee 1993, p. 133).
    Two additional, rare forest habitats are of particular relevance to 
coastal martens: Coastal serpentine and coastal dune forest. Forests in 
serpentine habitats are typically open and rocky with stunted trees 
that contrast sharply with the dense, rapidly-growing stands on more 
productive, non-serpentine soils that surround these sites (Jimerson et 
al. 1995, pp. A8-A31). Martens are not known to occupy these more open, 
drier, interior areas. However, on the extreme coastal edge of the 
serpentine habitats that occur in coastal northern California and 
coastal Oregon, increased moisture and summer fog supports dense, 
spatially-extensive shrub layers; coastal martens have been found in 
this wetter variant of coastal serpentine habitat in both Oregon and 
California. The serpentine communities used by coastal martens are 
composed of a variety of coniferous trees, such as Douglas-fir, sugar 
pine, lodgepole pine (Pinus contorta), western white pine (P. 
monticola), Jeffrey pine (P. jeffreyi), knobcone pine (P. attenuatta), 
and Port Orford-cedar, and are dominated by mast-producing shrubs such 
as dwarf tanbark, huckleberry oak, and red huckleberry (Jimerson et al. 
1995, p. C1; Slauson 2003, pp. 5, 9, 13). The coastal dune forest 
communities where coastal martens have been found are predominantly in 
coastal Oregon and are typically dominated by shore pine (P. contorta 
contorta), the coastal form of lodgepole pine, and in some areas co-
dominated by Sitka spruce occurring in stabilized dunes on marine 
terraces. Although martens have been found in these less-common habitat 
types, it is important to note that the more extensive dominant forest 
types (i.e., coastal coniferous forests) support the majority of the 
historical marten distribution in coastal Oregon and coastal northern 
California.
    Coastal martens select habitat at four primary spatial scales: 
Micro-scale (resting and denning structures), stand-scale, home range, 
and landscape-scale (facilitating movement, occupancy, and population 
dynamics).
    (1) Micro-scale--Rest structures are used daily by martens between 
foraging bouts to provide thermoregulatory benefits and protection from 
predators (Taylor and Buskirk 1994, pp. 253-255). Reuse rates for 
individual rest structures are low and selection for structure type 
changes seasonally to meet thermoregulatory needs (e.g., Spencer 1987), 
such that multiple resting structures meeting seasonal requirements are 
required across the home range. Large-diameter live trees, snags, and 
logs provide the main types of resting structures for martens (Spencer 
et al. 1983, pp. 1182-1185; Schumacher 1999, pp. 26-58; Slauson and 
Zielinski 2009, pp. 41-42). Denning structures used by female martens 
to give birth to kits are called natal dens, and the subsequent 
locations where they move their kits are referred to as maternal dens. 
Ruggiero et al. (1998, pp. 665-669) found that both the characteristics 
of the den structures and the characteristics of the stands in which 
they were found influenced den-site selection. This is likely due to 
the importance of high-quality foraging habitat in close proximity to 
den sites, allowing females to simultaneously maximize the energy they 
gain from foraging during lactation and minimize the time spent away 
from kits, especially when they are dependent on their mothers for 
thermoregulation. The most common den structures used by Pacific and 
American martens are large-diameter, live and dead trees with cavities 
(Thompson et al. 2012, p. 223).
    (2) Stand-scale--Martens select forest stands that provide habitat 
structure supporting one or more life history needs that include 
foraging, resting, or denning. Coastal martens in California most 
strongly selected stands of old-growth, conifer-dominated forests with 
dense shrub layers (Slauson et al. 2007, pp. 464-465). Other than the 
late-mature developmental stage, which was used in proportion to its 
availability, stands in earlier developmental stages were selected 
against (Slauson et al. 2007, pp. 462-464). These old-growth and late-
mature stands most often were dominated by Douglas-fir overstory, but 
also had mature hardwood understories composed of either tanoak or 
golden chinquapin. Shrub layers were dense (greater than 70 percent 
cover), spatially extensive, and dominated by evergreen huckleberry, 
salal, and rhododendron (Slauson et al. 2007, p. 465). The majority of 
detections of martens in coastal southern Oregon share these same stand 
characteristics (Zielinski et al. 2001, p. 485).
    (3) Home Range--Pacific and American martens exhibit strong habitat 
selection at the home range scale, suggesting that this scale of 
selection most directly influences an individual's fitness (Thompson et 
al. 2012, p. 210). Martens establish home ranges to encompass their 
year-round resource needs and, during the breeding season, gain access 
to members of the opposite sex. Marten home ranges are often positioned 
to maximize high-quality habitat (typically greater than 70 percent 
high-quality, late-successional forest (reviewed in Thompson et al. 
2012, p. 218)) and to minimize low-quality habitat (e.g., recent clear 
cuts, partial harvest) (Phillips 1994, pp. 59-60). Females, due to 
their solitary role raising young, have unique needs that require 
access to suitable den sites located near reliable and nearby prey 
resources to support the energetic demands of lactation and providing 
food for kits. In coastal northern California, Slauson and Zielinski 
(2014, unpubl. data) found 97 percent (38 of 39) of the female within-
home-range resting and active locations occurred in the core old-growth 
and late-mature

[[Page 18749]]

riparian habitat patches. In comparison, 77 percent (30 of 39) of the 
male within-home-range resting and active locations occurred in the 
core old-growth and late-mature riparian habitat patches (Slauson and 
Zielinski 2014, unpubl. data). Also of note is that there is an inverse 
relationship between the amount of high-quality habitat and marten home 
range size (i.e., as the amount of high-quality habitat decreases, home 
range size increases) (Thompson 1994, p. 276; Potvin and Breton 1997, 
p. 462; Fuller and Harrison 2005, pp. 715-719).
    (4) Landscape-scale--The pattern and composition of habitat at this 
scale affects: (a) The ability of martens to successfully disperse and 
find suitable home ranges; (b) survival and species occurrence over 
time and space; and (c) ultimately, population size and persistence. 
Successful dispersal requires the existence of functional habitat 
connectivity between patches of habitat suitable for reproduction to 
maintain or expand population size and distribution. Also, during 
dispersal, martens use a search strategy that is not random or linear, 
suggesting they are responding to habitat cues and that landscape 
pattern likely influences movement trajectories (Johnson 2008, pp. 27-
29, 36-39). Compared to other species closely associated with late-
successional forest, American and Pacific marten populations, including 
the coastal marten, are sensitive to the loss or fragmentation of high-
quality habitat at the landscape scale. For example, martens exhibit a 
progression of responses to timber harvest as the proportion of habitat 
affected by intensive logging activities increases. Such activities 
include, but are not limited to, clear cutting (see review in Thompson 
et al. 2012), partial harvest (Potvin et al. 2000, pp. 851-854; Fuller 
and Harrison 2005, pp. 715-716; Godbout and Ouellet 2008, pp. 336-338), 
and shelterwood cutting (Ellis 1998, p. 41-49). As a result, the 
combination of habitat loss and fragmentation of remnant suitable 
habitat effectively lowers the density of martens by reducing the 
number of home ranges that can be supported (Thompson 1994, p. 276).

Historical and Current Distribution of Coastal Martens and Suitable 
Habitat

    At the time of European settlement, the coastal marten occurred in 
all coastal Oregon counties and the coastal northern counties of 
California within late-successional coniferous forests. The majority of 
historical (pre-1980) verifiable marten detections (i.e., occurrence 
records supported by direct physical evidence such as tracks, 
photographs, and carcasses) were within the fog-influenced coastal 
coniferous forest as opposed to interior forests (Grinnell and Dixon 
1926, p. 413). Specifically, Slauson and Zielinski (2007, p. 241) 
reported 83 percent of the coastal northern California marten 
historical records occurring less than 25 km (15 mi) from the coast and 
no records occurring greater than 35 km (22 mi) from the coast, while 
our analysis (see Service 2015, pp. 6, 31) revealed greater than 90 
percent of the coastal Oregon marten historical records occurring 
closer to the coast than to the interior portions of the coastal 
marten's range. Historical abundance of coastal martens is unknown. 
However, as is typical of mammalian carnivores, coastal martens likely 
never occurred in high densities.
    Unregulated fur trapping occurred throughout the coastal marten's 
historical range, and by the late 1920s, few marten were captured where 
they were once considered relatively abundant (Zielinski and Golightly 
1996, entire). A marked decline in the number of coastal marten 
harvested in coastal northern California led to the closure of marten 
trapping in northwestern California in 1946. In Oregon, marten fur 
trapping remains legal Statewide. Historical fur trapping is thought to 
have resulted in a significant contraction of coastal marten 
distribution and the extirpation of coastal marten from large portions 
of its historical range. Although we can make conclusions about the 
general historical distribution of coastal martens, information on 
historical population size is not available, thus precluding an 
accurate assessment of the impact of unregulated trapping on coastal 
marten population abundance.
    Due to the lack of surveys for coastal martens, little information 
is available regarding their current distribution; this is particularly 
true for coastal Oregon. We do know, however, that there are at least 
three extant populations of coastal martens, one in coastal northern 
California, one in coastal southern Oregon, and one in coastal central 
Oregon, as described in detail below, and we have information regarding 
the extent of suitable habitat that is currently available to coastal 
martens throughout their range. It is therefore possible that coastal 
martens may occur in any of these areas of suitable habitat that have 
not been surveyed, or have been surveyed only sporadically. Here we 
briefly describe the areas of suitable habitat available to coastal 
martens.
    Slauson et al. (In prep.(b)) developed a landscape habitat 
suitability model that we used to assess how much suitable habitat is 
currently available to coastal martens. The model was developed by 
identifying the combination of environmental, topographic, disturbance 
history, and vegetation variables that best described the distribution 
of marten detection/non-detection survey data. Specifics regarding 
model development and variables can be found in the ``Current Landscape 
Habitat Suitability'' section of the Species Report (Service 2015, pp. 
26-27). The model categorizes the landscape into low, medium, and high 
suitability classes representing the relative probability of marten 
occupancy of habitat at the landscape scale.
    Model results indicate that approximately 41 percent of the coastal 
marten's historical range contain suitable habitat (described as low, 
medium, and high suitability habitat) for coastal martens (see 
``Current Landscape Habitat Suitability'' section of the Species 
Report). The model identified approximately 59 percent of the remaining 
lands within the historical range of the coastal marten to be 
unsuitable, which includes (but is not limited to) forested habitat 
that is not utilized by martens (e.g., heavily managed timber lands), 
urban and suburban developments, and agricultural lands. However, it is 
important to note that, for the purposes of this analysis, we 
considered ``low suitability habitat'' as defined in this model to be 
``unsuitable'' when examining the current and long-term stressors to 
the coastal marten and its habitat into the future. In other words, in 
evaluating stressors to the coastal marten and its habitat, we 
considered only areas that provide moderate- to high-suitability 
habitat as identified by the model. We came to this conclusion based on 
feedback from the species experts (Slauson et al., In prep.(a)) who 
indicate that these ``low suitability habitat'' areas currently have a 
low probability of coastal marten occurrence. Including these areas as 
suitable habitat for the purposes of this analysis would bias the 
amount of actual suitable habitat present both currently and in the 
future.
    Much of the coastal marten's historical habitat has been lost. 
Extensive logging of old-growth redwood habitat in coastal northern 
California began in the late 1800s, and coincided with unregulated fur 
trapping. Late-successional coniferous forests in coastal Oregon were 
also extensively harvested in the early 1900s. Currently, less than 5 
percent of the redwood forests existing at the time of European 
settlement remain within the

[[Page 18750]]

historical range of the coastal marten in coastal northern California 
(Save the Redwoods League 2015, no page number). Based on the best 
available information, much of the coastal coniferous forest habitat in 
both States, especially within a few miles of the coast, appears to be 
currently owned (in general) by either private industrial timber 
companies or smaller land owners, and managed for timber production.
    Within the coastal marten's historical range, the majority of 
remaining late-successional coniferous forests suitable for the coastal 
marten is within national forests, and national and State parks. Where 
martens are known to occur, relatively high amounts of moderate- to 
high-suitability habitat are still found, and much of this habitat 
occurs in areas that are managed for the maintenance or enhancement of 
late-successional forest conditions that are beneficial to coastal 
martens. For example, approximately 71, 79, and 90 percent of the total 
available suitable habitat on Federal lands in the coastal central 
Oregon, coastal southern Oregon, and coastal northern California 
population areas, respectively, occur within the Northwest Forest Plan 
(NWFP) Federal reserve lands, which are designed to retain and 
accelerate the development of late seral characteristics. Currently, 
the largest contiguous blocks of suitable coastal marten habitat occur 
within the Six Rivers National Forest in the extreme northern portion 
of the historical range in California, and in the adjacent Siskiyou 
portion of the Rogue River-Siskiyou National Forest in the southern 
portion of the historical range in Oregon. Large blocks of suitable 
habitat also occur in coastal central Oregon on the Siuslaw National 
Forest. Little suitable habitat is currently found in the southern half 
of the historical range in California. In the coastal northern portion 
of the historical range in Oregon, suitable habitat is limited to a 
narrow band along the coast. Finally, in the area between the Siskiyou 
and Siuslaw National Forests in the historical range in Oregon, there 
is some limited amount of suitable habitat on BLM ownership. Habitat 
conditions specific to each of the known extant population areas of 
coastal martens are discussed below.
Distribution and Abundance of Current Known Extant Populations
    There are three known extant populations of coastal martens in 
coastal central Oregon, coastal southern Oregon, and coastal northern 
California, according to the best available scientific and commercial 
data (Figure 1; see section 8.1.2 (Delineation of Extant Population 
Areas) of the Species Report (Service 2015, p. 32)). These populations 
have been described as disjunct (e.g., Slauson and Zielinski 2009, pp. 
35-36). Survey effort has been limited in some portions of the coastal 
marten's range, however. Therefore, it is unknown whether additional 
coastal martens may be found in areas that have not yet been surveyed. 
In addition, a few coastal marten verifiable detections occur outside 
these three population areas, but these martens are currently not 
considered part of any known viable population (Slauson et al., In 
prep.(a)). Surveys for martens have occurred in much of the California 
portion of the historical range and suitable interior habitat in 
southwestern Oregon, although minimal survey effort has occurred in 
coastal central Oregon and no surveys have occurred in coastal northern 
Oregon (see Figure 8.2 in the Species Report).
BILLING CODE 4310-55-P

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[GRAPHIC] [TIFF OMITTED] TP07AP15.011

BILLING CODE 4310-55-C

Coastal Central Oregon Extant Population Area

    This 4,150-km\2\ (1,602-mi\2\) population area includes all 
coastal-draining watersheds from the Umpqua River north to the Yaquina 
River in Lincoln, Benton, western Lane, western Douglas, and 
northwestern Coos Counties. Lands within this extant population area 
are owned/managed by Siuslaw National Forest (41 percent), private 
landowners (40 percent), Bureau of Land Management (BLM; 10 percent), 
and Oregon Department of Forestry (ODF) and Oregon State Parks (9 
percent). A total of approximately 2,348

[[Page 18752]]

km\2\ (907 square miles (mi\2\); 56 percent) of the extant population 
area contains moderate- and high-suitability habitat (Service 2015, p. 
33) for coastal martens. Of the currently available moderate- and high-
suitability habitat, 23 percent is in private ownership and 71 percent 
is in Federal ownership, and 71 percent of the Federal lands are in 
Reserves, which are managed for late-seral characteristics (Service 
2015, p. 76). The best available information suggests that most of the 
private forest land is owned by private, industrial timber companies 
(Lettman 2011, p. 33).
    This population area comprises approximately 20 percent coastal 
marten habitat of high suitability, 36 percent of moderate suitability, 
22 percent of low suitability (which has low probability of coastal 
marten occurrence currently and into the future), and 21 percent 
unsuitable (Slauson et al., In prep.(b)). In total, suitable marten 
habitat composes 78 percent of the population area. However, we note 
that the model (which used data from northwest California and southwest 
Oregon) generated suitable habitat values for this population area that 
did not include coastal dune habitat, which is considered suitable for 
coastal martens based on visual observations and the presence of 
several verifiable marten detections (Slauson et al., In prep.(a)). 
Thus the amount of potentially suitable habitat for coastal martens 
identified by the habitat model is an underestimate for this population 
area.
    Population abundance information is not available for the coastal 
central Oregon population of coastal martens. Although only a single 
station had been surveyed in this population area since the late 1980s, 
presence/absence surveys began in this area in the summer of 2014. One 
marten was detected in 2014 (Slauson et al. 2014, unpubl. data), and 
six more were detected in January and February 2015; as of the time of 
this publication, surveys in this area are ongoing (Moriarty 2015, 
pers. comm.). The area surveyed represents only about 4 percent of the 
currently delineated coastal central Oregon population area described 
herein, and 2014 was the first year of survey effort in this area. 
Based on the results to date and the availability of suitable habitat 
in this area, it is likely that more martens will be detected in this 
area as surveys continue.
    Abundance or trend information is not available for any populations 
of coastal martens in Oregon. Although researchers note that martens in 
this area have likely declined relative to their historical condition, 
they cite to insufficient historical or contemporary data to allow 
evaluation of the status of martens in the coastal mountain ranges of 
central and northern Oregon (Zielinski et al. 2001, p. 486). There are 
no data available for estimating current population abundance or trend 
for the coastal central Oregon population, and although survey efforts 
recently began in this area, data from these surveys will only be 
informative in terms of establishing presence or absence of coastal 
martens. Zielinski et al. (2001, pp. 486-487) could only suggest that 
marten numbers may be relatively low on the northern Oregon coast, 
based on the absence of reported road kills along coastal Highway 101 
in this area, in contrast to several road-killed martens reported from 
the same highway in central Oregon. In sum, although coastal martens 
have likely declined relative to their historical abundance due to the 
past effects of overtrapping and timber harvest (Zielinski et al. 2001, 
p. 487), there are no empirical data on which to base an estimate of 
either current population abundance or trend of martens on the central 
Oregon coast.

Coastal Southern Oregon Extant Population Area

    This 4,696-km\2\ (1,813-mi\2\) population area includes Chetco 
River, Pistol River, south Fork Rough and Ready Creek, and the North 
Fork Smith River watersheds in Curry, western Josephine, and southern 
Coos Counties. Lands within this population area are owned/managed by 
Rogue River-Siskiyou National Forest (78 percent), private landowners 
(13 percent), BLM (8 percent), and ODF (less than 1 percent). A total 
of approximately 3,641 km\2\ (1,406 mi\2\; 78 percent) of the extant 
population area contains moderate- and high-suitability habitat 
(Service 2015, p. 35). As stated above for the coastal central Oregon 
population area, present moderate- and high-suitability habitat on 
private lands is expected to be harvested or not likely to retain late-
seral characteristics into the future. Of the currently available 
moderate- and high-suitability habitat in the coastal southern Oregon 
population area, 10 percent is private ownership and 90 percent is 
Federal ownership, and 79 percent of the federally managed lands are 
Federal Reserves, which are managed for late-seral characteristics 
(Service 2015, p. 76). The best available information suggests that 
most of the private forest land is owned by private, industrial timber 
companies (Lettman et al. 2011, p. 33).
    This population area comprises approximately 52 percent coastal 
marten habitat of high suitability, 26 percent of moderate suitability, 
17 percent of low suitability, and 5 percent unsuitable (Slauson et 
al., In prep.(b)). In total, suitable marten habitat composes 95 
percent of the population area.
    Similar to the situation for the coastal central Oregon population, 
described above, population abundance information is not available for 
the coastal southern Oregon population of coastal martens. Although 
extensive grid-based surveys (which are used to estimate marten 
abundance or presence/absence) have not been conducted for this 
population, grid-based surveys began in this area in the summer of 
2014. No coastal martens were detected in 2014 (Slauson et al. 2015, 
unpubl. data), but surveys just beginning at the time of this 
publication have yielded a single marten detection (Moriarty 2015, 
pers. comm.). The area surveyed represents only a small portion of the 
currently delineated coastal southern Oregon population area described 
herein, and 2014 represented the first year of survey effort in this 
area. At this time, similar to the coastal central Oregon population 
area, there are no empirical data on which to base an estimate of 
either current population abundance or trend of martens on the southern 
Oregon coast.

Coastal Northern California Extant Population Area

    This 812-km\2\ (313-mi\2\) population area includes the south Fork 
of the Smith River, Blue Creek, Bluff Creek, Camp Creek, Cappell Creek, 
Pecwan Creek, Slate Creek, and Rock Creek (Siskiyou County, north of 
Orleans, California) watersheds in Del Norte, northern Humboldt, and 
western Siskiyou Counties. Lands within this population area are owned/
managed by the U.S. Forest Service (Forest Service) (Klamath National 
Forest and Six Rivers National Forest; 65 percent); the Yurok Tribe of 
the Yurok Reservation, California (Yurok Tribe; 23 percent); private 
landowners, primarily Green Diamond Resource Company (11 percent); and 
Redwood National and State Parks (1 percent). A total of approximately 
656 km\2\ (253 mi\2\; 81 percent) of the extant population area 
contains moderate- and high-suitability habitat (Service 2015, p. 75). 
Currently present moderate- and high-suitability habitat on private 
lands is expected to be harvested or not likely to retain late-seral 
characteristics into the future. Of the currently available moderate- 
and high-suitability habitat in the coastal northern California 
population area, 11 percent is private ownership and 77

[[Page 18753]]

percent is Federal ownership, and 90 percent of the federally managed 
lands are Federal Reserves, which are managed for late-seral 
characteristics (Service 2015, p. 75). The best available information 
suggests that most of the private land is owned by private, industrial 
timber companies (Service 2014, unpubl. data).
    This population area comprises approximately 67 percent coastal 
marten habitat of high suitability, 14 percent of moderate suitability, 
7 percent of low suitability, and 12 percent unsuitable (Slauson et 
al., In prep.(b)). In total, suitable marten habitat composes 88 
percent of the population area.
    As reported in 1996 by Zielinski and Golightly (1996, entire), this 
coastal northern California population has apparently recovered from 
numbers that were once so low (in the 50 years prior to 1995) that it 
was considered to be extremely rare or extinct. Martens in coastal 
northern California were first surveyed to estimate abundance in 2000-
2001, and again in 2008 (Slauson et al. 2009b, p.11) and 2012 (Slauson 
et al. 2014, unpubl. data). A total of 31.5 martens (95 percent 
confidence interval = 24-40) were estimated for 2000-2001, and 20.2 
martens (95 percent confidence interval = 11-30) were estimated for 
2008, which represents a 42 percent decline in occupancy between those 
two time periods (Slauson et al. 2009b, pp. 10, 11). In 2012, all 
locations sampled in 2008 were resampled (Slauson et al., In prep.(a)). 
Preliminary occupancy estimates for the 2012 sampling were similar to 
results from 2008 (Slauson et al., In prep.(a)), suggesting no further 
changes in marten population abundance in northern coastal California 
between 2008 and 2012. Slauson et al. (2009b, p. 13) advised that these 
population estimates should be considered minimum estimates because the 
sampling area did not fully cover all potentially occupied habitats; 
therefore, they suggested more realistic population estimates should be 
doubled (i.e., 60 coastal martens in 2000-2001, and 40 in 2008). Based 
on these samples, Slauson et al. (2009b, p. 13) concluded that as of 
2008, it was likely that the entire coastal northern California 
population of martens contained fewer than 100 individuals. As noted 
above, subsequent survey efforts in 2012 indicated no further changes 
in estimated population size since that time; therefore, the best 
available data (preliminary estimates from surveys in 2012) suggest 
that the current population estimate for the coastal northern 
California population is similar to the estimate for 2008 (i.e., fewer 
than 100 individuals).

Summary of Information Pertaining to the Five Factors

    Section 4 of the Act (16 U.S.C. 1533) and implementing regulations 
(50 CFR 424) set forth procedures for adding species to, removing 
species from, or reclassifying species on the Federal Lists of 
Endangered and Threatened Wildlife and Plants. Under section 4(a)(1) of 
the Act, a species may be determined to be an endangered or threatened 
species based on any of the following five factors:
    (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range;
    (B) Overutilization for commercial, recreational, scientific, or 
educational purposes;
    (C) Disease or predation;
    (D) The inadequacy of existing regulatory mechanisms; or
    (E) Other natural or manmade factors affecting its continued 
existence.
    In making this finding, information pertaining to the coastal DPS 
of the Pacific marten in relation to the five factors provided in 
section 4(a)(1) of the Act is discussed below. In considering what 
factors might constitute threats to a species, we must look beyond the 
mere exposure of the species to a particular factor to evaluate whether 
the species may respond to that factor in a way that causes actual 
impacts to the species. If there is exposure to a factor but no 
response, or only a positive response, that factor is not a threat. If 
there is exposure and the species responds negatively, the factor may 
be a threat and we then attempt to determine if that factor rises to 
the level of a threat, meaning that it may drive or contribute to the 
risk of extinction of the species such that the species warrants 
listing as an endangered or threatened species as those terms are 
defined in the Act. However, the identification of factors that could 
impact a species negatively is not sufficient to compel a finding that 
the species warrants listing. The information must include evidence 
sufficient to suggest that these factors are operative threats that act 
on the species to the point that the species meets the definition of an 
endangered or threatened species under the Act.
    Potential stressors that may impact coastal martens in coastal 
Oregon and coastal northern California include actions that may affect 
marten individuals or populations (i.e., trapping (for fur and research 
purposes), predation, disease, collision with vehicles, and exposure to 
toxicants) and actions that may lead to the loss, degradation, or 
fragmentation of suitable marten habitat (i.e., wildfire, climate 
change, vegetation management, and development). To provide a temporal 
component to our evaluation of potential stressors (i.e., impacts into 
the future), we first determined whether we had data available that 
would allow us to reasonably predict the likely future impact of each 
specific stressor over time. Where such data were available, we made 
predictions of future conditions over a period of time specific to that 
stressor (i.e., wildfire, climate change, as described below). If we 
did not have such stressor-specific data available, we used IUCN's 
standard 3-generation timeframe to assess risk (International Union for 
Conservation of Nature (IUCN) 2014, pp. 14-21). Using a calculated 
marten generation time of 5 years (see the Species Report for more 
information on calculating marten generation time), this translated to 
a timeframe of 15 years, which we used in analyzing the foreseeable 
future for the majority of the stressors discussed below. This time 
period allows for analysis of multiple generations of coastal martens 
over a reasonable time period, as opposed to examining further into the 
future where assumptions or extensive uncertainty would not allow 
meaningful projections of potential future impacts.
    To assess the stressor of wildfire, we used a longer future period 
consisting of 30 years based on more extensive data available regarding 
wildfires from the past approximate 30 years. This information was used 
to predict the future equivalent level of expected fire frequency, 
size, and severity. Using a longer foreseeable future timeframe for 
wildfire better incorporates the range of fire-related activity that 
may occur within the coastal Oregon and coastal northern California 
population areas. To assess the stressor of climate change, we used a 
longer foreseeable future period of 40-50 years, which coincides with 
the model projection timeframes available for climate change (e.g., 
changes in temperature and precipitation) in coastal Oregon and coastal 
northern California. Climate projections beyond this approximate time 
period diverge with increasing uncertainty (see, e.g., Lenihan et al. 
2008, pp. 16-17), including uncertainties in the magnitude and timing, 
as well as regional details, of predicted climate change, especially at 
smaller scales (IPCC 2015, no page number), which is why we cannot 
reliably project future climate change effects beyond this timeframe.
    A thorough review of each of the potential stressors is presented 
in the Species Report (Service 2015, pp. 41-78), which is available on 
the Internet

[[Page 18754]]

at http://www.regulations.gov, Docket No. FWS-R8-ES-2011-0105. A 
summary of this information is presented below.
    Each potential stressor was evaluated to determine the likely 
impact to coastal martens or their habitat.
     A low-level impact indicates: (1) Individual martens in 
one or more populations may be impacted, but not at the population 
level; or (2) minimal loss, degradation, or fragmentation of suitable 
habitat.
     A medium-level impact indicates: (1) Individual martens in 
one or more populations are being impacted, likely resulting in a 
population-level impact; or (2) moderate loss, degradation, or 
fragmentation of suitable habitat.
     A high-level impact indicates: (1) Individual martens in 
one or more populations are being impacted, likely resulting in a 
significant population-level impact; or (2) significant loss, 
degradation, or fragmentation of suitable habitat.

Factor A--The Present or Threatened Destruction, Modification, or 
Curtailment of the Species' Habitat or Range

Wildfire
    Wildfire can impact individual coastal martens directly through 
mortality (Factor E); however, fires generally kill or injure a 
relatively small proportion of animal populations, particularly if they 
are mobile (Lyon et al. 2000, pp. 17-20), and the best available data 
do not indicate that wildfire is causing loss of individual martens. If 
direct mortality of individual martens occurs, we expect the impact to 
be discountable because martens are capable of rapid evacuation from an 
approaching fire, and adequate suitable habitat likely exists within 
their extant population areas to establish a new home range (provided 
the majority of the suitable habitat within the extant population area 
is not subjected to an overly large, high-severity wildfire).
    Wildfire is a major disturbance force of habitat within the range 
of the coastal marten in all but the wettest coastal forests and thus 
has been analyzed in terms of its effect on coastal marten habitat. 
Wildfire can affect the composition and structural characteristics of 
the forest communities at multiple spatial and temporal scales. Fire 
severity is often expressed in categories of high, medium, or low 
severity, as well as mixed severity. High-severity fire, also called 
stand-replacing fire, kills all or nearly all vegetation within a stand 
and may extend across a landscape (Jain et al. 2012, p. 47). Medium-
severity fire refers to fire that is intermediate in its effects 
between high-severity and low-severity fire; for example, a fire may 
kill scattered clumps of overstory trees within a stand. Low-severity 
fire burns at ground-level and does not kill most overstory trees, 
although it may consume understory vegetation and downed woody debris 
(Jain et al. 2012, p. 47). Finally, mixed-severity fire includes 
patches of low-severity fire and patches of high-severity fire (Jain et 
al. 2012, p. 47).
    Regional moisture gradients result in wildfires occurring more 
frequently with increasing distance from the coast and farther south in 
the coastal marten's range. The effect of fire on coastal marten 
habitat varies from high-severity fires that consume much or all of the 
structural features (e.g., large trees, snags, logs) that are important 
elements of suitable coastal marten habitat, requiring centuries to 
regrow, to low-severity fires that burn only the dense, shade-tolerant 
shrub layer preferred by the coastal marten (Slauson et al. 2009b, p. 
11). The shrub layer likely takes 1 to 2 decades to regrow to suitable 
size and density, depending on its fire resistance and adaptive 
response to disturbances (Slauson 2014, pers. comm.). However, some 
low-severity fires may burn ground cover without burning the dense, 
shade-tolerant shrub layer preferred by the coastal marten. Wildfires 
within the range of the coastal marten often burn at mixed severities 
(Landscape Fire and Resource Management Planning Tools Project 
(LANDFIRE) 2008a; LANDFIRE 2008b; LANDFIRE undated(a)), with some areas 
within the fire perimeter burning at a high severity, resulting in 
stand replacement, and other portions burning at low severity, 
resulting in the loss of only ground vegetation. Fire effects are 
complex; therefore, potential impacts of future wildfires on coastal 
marten suitable habitat are difficult to predict.
    Historical fire records indicate that, compared to the coastal 
central Oregon population area, the coastal northern California and 
coastal southern Oregon population areas (including adjacent or 
intervening areas) have experienced larger and more severe wildfires 
(Monitoring Trends in Burn Severity (MTBS; 2013, entire), both also 
experiencing many small (less than 0.4 hectares (ha) (1 acre (ac)) 
fires. The potential for severe, stand-replacing wildfire has increased 
in some areas where fire suppression and regeneration timber harvest 
(i.e., the intent to develop a new stand/forest) have played a role in 
raising fuel load to levels that place late-successional forest at 
increased risk (Forest Service and BLM 1994b, pp. 3, 4-49). Although 
fire suppression is known to contribute to the severity of wildfire in 
some areas, within at least parts of coastal northern California and 
coastal southern Oregon, fire suppression has had little effect on 
altering the structure and composition of the dominant forest types and 
has not caused an increase in high-severity fire compared to the 
historical patterns (Odion et al. 2004, pp. 933-935; Miller et al. 
2012, p. 200). In other words, the period of fire suppression may not 
be long enough to manifest such effects in coastal forest types where 
the return intervals for high-severity, stand-replacing fires are on 
the order of centuries (e.g., Veirs 1982, pp. 132-133; Oneal et al. 
2006, pp. 82-87).
    The best available historical fire information and the more xeric 
nature (i.e., environment containing little moisture) of the interior 
within the Klamath Ecoregion indicate that future loss, degradation, or 
fragmentation of moderate- and high-suitability coastal marten habitat 
from wildfires will likely result in a greater impact in the coastal 
southern Oregon and coastal northern California populations as compared 
to the coastal central Oregon population. However, the more coastal 
climate where most martens occur may have an ameliorating effect (e.g., 
increased humidity, reduced temperatures) on fires, reducing the size 
of fires in the coastal area compared to those more characteristic of 
the rest of the Klamath Ecoregion. Historical data between 1984 and 
2012 indicate that wildfires burned approximately 17 percent and 42 
percent of the combined moderate- and high-suitability coastal marten 
habitat within the coastal northern California and coastal southern 
Oregon population areas, respectively, with a few large fires 
responsible for the majority of burned suitable habitat (MTBS 2013, 
entire). We note that these wildfires burned at varying levels of 
severity; in other words, although some suitable habitat was lost as a 
result of the wildfires, varying levels of suitable habitat remain 
throughout the population areas, with moderate- and high-suitability 
habitat remaining within the wildfire perimeters after the fires were 
extinguished (Service 2014, unpubl. Geographic Information System (GIS) 
analysis).
    It is possible that fire frequency, size, and severity may increase 
in the future within coastal Oregon (both central and southern) and 
coastal northern California, based on projected increases in 
temperature and decreased precipitation (see ``Climate Change,'' 
below), with potentially greater

[[Page 18755]]

increases within coastal southern Oregon and coastal northern 
California based on the history of wildfire within these portions of 
the coastal marten's range. In contrast, little moderate- and high-
suitability coastal marten habitat has burned (historically, between 
1984 and 2012) within and adjacent to the coastal central Oregon 
population area (MTBS 2013, entire). Large, stand-replacing fires occur 
infrequently (at intervals greater than 200 to 250 years) within 
coastal central Oregon (Impara 1997, p. 92; Long et al. 1998, p. 786; 
Long and Whitlock 2002, p. 223l; LANDFIRE 2008a). In general, most 
fires that have recently occurred within the range of coastal marten 
have burned at mixed severity (e.g., LANDFIRE 2008a; LANDFIRE 2008b; 
LANDFIRE undated(a)), resulting in some areas burning at a lower 
intensity with loss of only ground or shrub understory vegetation, and 
retaining of a portion of the moderate- and high-quality habitat within 
the fire perimeters.
    In our initial development of the Species Report, we identified an 
overall low-level impact across the northern portion of the coastal 
marten's range, and a medium-level impact across the southern portion 
of the coastal marten's range (see section 9.2.3.1 in the Species 
Report). These overall impact levels were based on the probability of 
occurrence of a wildfire over a 15-year time period. When considering 
historical fire data over a 30-year time period to predict the future 
equivalent level of expected fire frequency, size, and severity (see 
Appendix A in the Species Report), the overall level of impact (i.e., 
probability of occurrence of a wildfire) is potentially the same. 
However, this impact level estimate does not take into account the 
historical fire data (e.g., LANDFIRE 2008a; LANDFIRE 2008b; LANDFIRE 
undated(a)) that show most wildfires burned at low severity and 
retained moderate- and high-quality habitat post-fire.
    Based on the analysis contained within the Species Report and 
summarized above, we expect that within the range of the coastal 
marten, the incidence of wildfire in the future will be similar to that 
recorded for 1984 to 2012. We note, however, that high-severity fires 
have been infrequent in the past and are considered to remain 
infrequent, overall, into the future. Our expectation is that fire 
frequency, size, and severity in the future will be fairly similar (or 
slightly higher in some areas based on climate change predictions). 
Based on these 30 years (i.e., 1984-2012) of data, we can reasonably 
estimate these effects will continue with the same approximate level of 
impact into the next 30 years as has occurred over the previous 30 
years (i.e., mixed severity wildfires will likely occur although most 
will be low severity and retain some moderate- and high-quality habitat 
post-fire); thus, we predict that, overall, these impacts do not rise 
to the level of a threat. We base this conclusion on:
    (1) The persistence of moderate- and high-quality habitat that has 
remained following recent large wildfires (i.e., wildfires that have 
burned at mixed severities (LANDFIRE 2008a; LANDFIRE 2008b; LANDFIRE 
undated(a)), which have not resulted in extensive stand-replacement 
within the coastal marten's range.
    (2) The overall continued presence of relatively moist habitat 
conditions for coastal marten habitat, primarily along the western 
coast, including overall cooler, moist summer conditions that moderate 
the dry conditions that promote fire ignition and spread.
    (3) Information indicating that parts of coastal northern 
California and coastal southern Oregon have experienced fire 
suppression with little effect on altering the structure and 
composition of the dominant forest types, and no increase in high-
severity fire compared to the historical patterns (Odion et al. 2004, 
pp. 933-935; Miller et al. 2012, p. 200).
Climate Change
    ``Climate'' refers to the mean and variability of weather 
conditions over time, with 30 years being a typical period for such 
measurements, although shorter or longer periods also may be used 
(Intergovernmental Panel on Climate Change [IPCC] 2013, p. 1,450). The 
term ``climate change'' thus refers to a change in the mean or 
variability of one or more measures of climate (e.g., temperature or 
precipitation) that persists for an extended period, typically decades 
or longer, whether the change is due to natural variability, human 
activity, or both (IPCC 2013, p. 1,450). A recent synthesis report of 
climate change and its effects is available from the IPCC (IPCC 2014, 
entire).
    Changes in climate may have direct or indirect effects on species. 
These effects may be positive, neutral, or negative, and they may 
change over time, depending on the species and other relevant 
considerations, such as interactions of climate with other variables 
(e.g., habitat fragmentation, fire frequency) (IPCC 2007, pp. 8-14, 18-
19). Typically, expert judgment and appropriate analytical approaches 
are used to weigh relevant information, including uncertainty, in 
various aspects of climate change.
    Global climate projections are informative, and in some cases, the 
only scientific information available. However, projected changes in 
climate and related impacts can vary substantially across and within 
different regions of the world (e.g., IPCC 2007, pp. 8-12). Therefore, 
we use ``downscaled'' projections (see Glick et al. 2011, pp. 58-61, 
for a discussion of downscaling) when they are available and have been 
developed through appropriate scientific procedures, because such 
projections provide higher resolution information that is more relevant 
to spatial scales used for analyses of a given taxon. For this analysis 
across the range of the coastal marten, downscaled projections are used 
in addition to some regional climate models that provide higher 
resolution projections using a modeling approach that differs from 
downscaling. The geographic region of the projections is the southern 
terminus of temperate rainforests of the North American continent, 
which encompasses the range of the coastal marten.
    Climate throughout the range of the coastal marten is projected 
over the next approximately 40 to 50 years to become warmer, and in 
particular summers will be hotter and drier, with more frequent heat 
waves (Pierce et al. 2013, p. 848; Cayan et al. 2012, p. 10; 
Salath[eacute] et al. 2010, p. 69; Tebaldi et al. 2006, pp. 191-200; 
Hayhoe et al. 2004, p. 12423). However, the northern portion of the 
coastal marten's range will likely experience winters that may become 
wetter, although warmer temperatures may result in an overall water 
deficit (Pierce et al. 2013, p. 848; Cayan et al. 2012, p. 10; 
Salath[eacute] et al. 2010, p. 69; Tebaldi et al. 2006, pp. 191-200; 
Hayhoe et al. 2004, p. 12423). The coastal marten's currently suitable 
habitat may be affected by climate change to some extent. At this time, 
nearly all models for the coastal northern California and coastal 
southern Oregon population areas predict shifts in vegetation type over 
time from conifer forest to mixed-conifer hardwood forest, as well as 
shifts toward woodland and chaparral, with some shifts predicted to be 
observable by 2030, but most by the end of the century (roughly 2070 
through 2099) (Whitlock et al. 2003, p. 16; Rehfeldt et al. 2006, p. 
1143; Lenihan et al. 2008, p. 20; Doppelt et al. 2009, p. 7; Littell et 
al. 2011, pp. 11-12; Shafer et al. 2010, pp. 180-181; Littell et al. 
2013, pp. 113-115). The predicted extent and nature of these shifts and 
the potential rate of change vary greatly, depending on

[[Page 18756]]

potential emissions scenarios, assumptions (for example, in how various 
plant species are likely to respond to changes in temperature, 
precipitation, and carbon dioxide concentration), and variables 
incorporated into the models. Despite these differences, most models 
produce qualitatively similar forecasts of the impacts of potential 
future climates on ecosystem distribution, function, and disturbances 
(Shafer et al. 2010, p. 179). Although climate models have become 
increasingly sophisticated, the simulated future response of ecosystems 
remains subject to great uncertainty due to a number of factors, 
especially over longer timeframes (see, e.g., Lenihan et al. 2008, pp. 
16-17). In sum, although there is general agreement in the direction 
and nature of changes anticipated, models continue to have limitations 
which lead to uncertainties in the magnitude and timing, as well as 
regional details, of predicted climate change, especially at smaller 
scales (IPCC 2015, no page number) Thus, although we anticipate the 
coastal marten's currently suitable habitat may be affected by climate 
change to some extent, there is a high level of uncertainty regarding 
the nature of any such effects and the likelihood and timing of their 
occurrence.
    In coastal central and northern Oregon, models also project shifts 
by the end of this century in vegetation type from maritime conifer 
forest toward mixed conifer-hardwood and deciduous forests, although 
models differ in the extent of this change (Whitlock et al. 2003, p. 
16; Rehfeldt et al. 2006, p. 1143; Lenihan et al. 2008, p. 20; Doppelt 
et al. 2009, p. 7; Littell et al. 2011, pp. 11-12; Shafer et al. 2010, 
pp. 180-181; Littell et al. 2013, pp. 113-115). These shifts in future 
vegetation type may lead to range shifts for the coastal marten, 
although information is not available to indicate how rapidly this may 
occur. It is important to note that studies of climate change present a 
range of effects including some that indicate conditions could remain 
suitable for coastal martens. For example, in areas with stable or 
increasing total precipitation, overall warmer temperatures are 
expected to result in a decreased snowpack ((Cayan et al. 2012, pp. 20-
21; Littell et al. 2011, p. 60; Salath[eacute] et al. 2010, pp. 66-68; 
Hayhoe et al. 2004, p. 12423), which would result in increased 
availability of habitat for coastal martens at higher elevations, as 
well as increased availability of prey during the winter months 
(Service 2015, p. 7). Overall, it is not clear how finer-scale abiotic 
factors may shape local climates and influence local vegetation trends 
either to the benefit or detriment of coastal martens, nor is the 
timeframe clear over which these influences may be realized.
    We note that redwood forest habitat within coastal national and 
State parks to the west of the coastal northern California population 
area may remain suitable for coastal martens even with projected 
changes in climate (based on a moderate emissions scenario within 50 
years; DellaSala 2013, entire). However, to reach this coastal redwood 
habitat, martens would need to traverse many kilometers of unsuitable 
habitat (i.e., industrial timberlands). Martens actively select against 
these areas that do not have protective overstory cover; however, 
limited movement across unsuitable habitat areas may occur. In 
contrast, coastal martens currently occurring within the drier, 
interior portions of the coastal southern Oregon population area could 
migrate into other suitable habitat to the west as climate change 
alters the more interior habitat; a natural, westward migration is 
possible due to a lack of significant physical barriers to east-west 
movements within that region.
    Overall, studies of climate change present a range of effects on 
vegetation, including some that indicate conditions could remain 
suitable for coastal martens in portions of the coastal range; 
furthermore, the severity of potential impacts to coastal marten 
habitat will likely vary across the range, with effects to coastal 
martens potentially ranging from negative, neutral, or beneficial. 
Thus, the Species Report described an estimated range of low- to 
medium-impact for this stressor for coastal southern Oregon and coastal 
northern California (Service 205, pp. 67-72). Modeling projections are 
done at a large scale, and effects to species' habitat can be complex, 
unpredictable, and highly influenced by local-level biotic and abiotic 
factors. Although many climate models generally agree about the changes 
in temperature and precipitation, the consequent effects on vegetation 
are more uncertain, as is the rate at which any such changes might be 
realized. Therefore, it is not clear how or when changes in forest type 
and plant species composition will affect the distribution of coastal 
marten habitat. How any such changes may in turn affect coastal marten 
populations is even more uncertain. Thus, uncertainty exists when 
determining the level of impact climate change may have on coastal 
marten habitat. Consequently, at this time and based on the analysis 
contained within the Species Report and summarized above, we have 
determined that we do not have reliable information to indicate that 
climate change is a threat to coastal marten habitat now or in the 
future, although we will continue to seek additional information 
concerning how climate change may affect coastal marten habitat.
Vegetation Management
    Vegetation management includes activities such as timber harvest, 
thinning, fuels reduction, and habitat restoration, which can result in 
the temporary or permanent loss, degradation, or fragmentation of 
suitable coastal marten habitat. Once lost, structural elements found 
in suitable coastal marten habitat that are required for denning and 
resting (such as large diameter live trees, snags, and logs) require 
more than a century to develop (Slauson and Zielinski 2009, p. 43). 
Slauson (2014, pers. comm.) anticipates that loss of the dense, shade-
tolerant shrub layer required by the coastal marten would take 1 to 2 
decades to regrow.
    Historically, vegetation management activities (particularly large-
scale harvest of late-successional coniferous forest habitat) reduced 
the amount and distribution of suitable coastal marten habitat. At the 
present time, although the reduction and fragmentation of some suitable 
coastal marten habitat is expected to continue, the majority of 
suitable habitat for coastal martens is currently secure and expected 
to increase in the future. Habitat loss and degradation is expected to 
be realized primarily on private lands, which constitute a relatively 
small proportion of the suitable habitat available to martens in the 
three extant population areas (23 percent in coastal central Oregon, 10 
percent in coastal southern Oregon, and 11 percent in coastal northern 
California). In contrast, most suitable marten habitat is in Federal 
ownership (71 percent in the coastal central Oregon population area, 90 
percent in the coastal southern Oregon population area, and 77 percent 
in the coastal northern California population area), and the majority 
of those lands are in reserve allocations under the NWFP, which are 
managed for the maintenance or development of late-successional forest 
characteristics (71 percent of Federal lands in reserves in coastal 
central Oregon, 79 percent of Federal lands in reserves in coastal 
southern Oregon, and 90 percent of Federal lands in reserves in coastal 
northern California). We therefore expect not only the maintenance but 
further recruitment of suitable coastal marten

[[Page 18757]]

habitat on Federal reserve lands over time.
    Some vegetation management activities (such as thinning, fuels 
reduction projects, and habitat restoration) have the potential to 
improve habitat suitability for the coastal marten in the long term by 
minimizing loss of late-successional stands due to wildfires and 
accelerating the development of late-seral characteristics (Zielinski 
2013, pp. 419-422). This has been suggested for a similar mustelid, the 
fisher, where such activities may be consistent with maintaining 
landscapes that support fishers in the long term and sometimes even the 
short term, providing treatments retain appropriate habitat structures, 
composition, and configuration (Spencer et al. 2008, entire; Scheller 
et al. 2011, entire; Thompson et al. 2011, entire; Truex and Zielinski 
2013, entire; Zielinski 2013, pp. 17-20). Thus, it is reasonable to 
assume that these types of projects could increase the long-term, 
overall amount, distribution, and patch size of suitable coastal marten 
habitat, although some short-term degradation, loss, or fragmentation 
of suitable coastal marten habitat may occur in the interim.
    On lands managed for industrial timber harvest, the past and 
current practice of managing coastal coniferous forests on a short-
rotation system (40-60 years) to maximize wood production has reduced 
the complexity of the shrub and herb layers, which are important 
components of suitable marten habitat. These management practices have 
also precluded development of late-successional forest characteristics 
that are important to the coastal marten (such as large diameter logs, 
snags, and trees). Short-rotation forestry is prevalent on private 
lands, whereas only a small fraction of forested Federal lands (i.e., 
``matrix'' lands as defined under the NWFP) may be used for timber 
harvest.
    Due to current and expected future intensive timber-harvesting 
activities, we do not anticipate that private lands would support 
viable marten populations or maintain important habitat elements in the 
future. Instead, the coastal marten relies on (and our analysis 
considers) the maintenance of suitable coastal marten habitat on 
Federal and State lands as the key element to support the long-term 
viability of coastal marten populations. Of the coastal marten suitable 
habitat within the three extant population areas, from 71 to 90 percent 
is on Federal lands and in reserve status under the NWFP, much of which 
is managed specifically for the development of late-successional 
characteristics that will be beneficial for coastal martens. 
Specifically, and at present:
    (1) In the coastal central Oregon extant population area, 79 
percent of the habitat is considered suitable for coastal martens (56 
percent moderate to high suitability). Approximately 71 percent of the 
moderate- to high-suitability habitat occurs within Federal ownership, 
and 71 percent of that is Federal Reserve land.
    (2) In the coastal southern Oregon extant population area, 95 
percent of the habitat is considered suitable for coastal martens (78 
percent moderate to high suitability). Approximately 90 percent of the 
moderate- to high-suitability habitat is in Federal ownership, and 79 
percent of that is Federal Reserve land.
    (3) In the coastal northern California extant population area, 87 
percent of the habitat is considered suitable habitat for coastal 
martens (81 percent moderate to high suitability). Approximately 77 
percent of that is in Federal ownership, and 90 percent of that is 
Federal Reserve land.
    A small proportion of the moderate- and high-suitability habitat 
occurs on Federal matrix lands (i.e., lands as defined under the NWFP 
that are used for timber harvest). The rate of loss of late-
successional and old-growth forest on Federal lands due to timber 
harvest has declined substantially since the implementation of the NWFP 
(Mouer et al. 2011, entire). Although the NWFP does not recognize 
marten habitat as a forest class or condition, late-successional old 
growth forest likely includes a subset of coastal marten habitat (if 
the necessary dense shrub layer is present).
    Based on the analysis contained within the Species Report and 
summarized above, including the proportion of moderate- and high-
suitability coastal marten habitat available and the favorably managed 
forested lands (primarily Federal Reserves) within each extant 
population area, we consider ongoing vegetation management to have a 
low impact on the loss, degradation, or fragmentation of suitable 
coastal marten habitat across the range of the DPS both currently and 
into the future. We note that loss of suitable habitat (primarily low-
quality suitable habitat) is expected to continue to occur into the 
future on private lands within all three population areas, potentially 
to a greater extent in the coastal central Oregon population area due 
to a larger percentage of privately-owned timber lands within that 
population area. For the entire range, we considered vegetation 
management as a low-level impact on moderate and high suitability 
marten habitat for Federal lands, which constitute a majority of the 
extant population areas, have longer harvest rotations, and retain more 
structural features on the subset of that area in matrix, or where 
habitat will be retained on lands in Federal Reserves. In addition, 
because of the extent of Federal reserve land allocations that are 
designed to maintain and develop late-successional conditions, an 
unquantifiable amount of suitable habitat for coastal martens is 
expected to develop in the future. Overall, potential impacts from 
vegetation management do not rise to the level of a threat given the 
extensive beneficial land management practices expected to continue 
into the future (15 years) on public lands.
Development
    Some impacts to suitable habitat are expected to occur within the 
range of the coastal marten as a result of development activities such 
as road building, dam construction and creation of new reservoirs, 
conversion of forest habitat for agricultural use, development and 
expansion of recreational areas (e.g., golf courses, campgrounds, and 
trails), urban expansion, and rural development. Should these types of 
disturbances occur, they would likely result in the further loss, 
degradation, or fragmentation of suitable habitat. However, if these 
activities occur into the future, only a small amount of habitat may be 
impacted rangewide based on our evaluation of the best available data 
at this time because most of the potential development is expected on 
private lands that afford the coastal marten little suitable habitat to 
begin with. In addition, many of the areas that provide suitable 
habitat for coastal martens are areas of challenging topography that 
are not conducive to intensive or large-scale development.
    In Oregon, the greatest rates of change from resource land use to 
more developed use occurred prior to 1984, before implementation of 
county land-use plans and land-use planning laws (Oregon Administrative 
Rule 660-015-00) that limit the conversion of designated resource 
lands, including forest lands, to other uses (Lettman et al. 2011, p. 
16). These laws encourage intensified development in areas already 
urbanizing, while limiting development in more rural areas (Lettman et 
al. 2009, p. 4; Lettman et al. 2011, p. 9). Consequently, conversion of 
non-Federal forest land has been limited in Oregon, with 98 percent of 
all non-Federal forest, agricultural, and range

[[Page 18758]]

lands in the State in 1974 remaining in those uses in 2009 (Lettman et 
al. 2011, p. 11). Virtually all land-use change during this time 
occurred on private land (Lettman et al. 2011, p. 11). However, 
development of private land within 1.6 km (1 mi) of Federal forest land 
is increasing, which can affect management along the periphery of 
adjacent Federal lands, such as increasing the need for fuel treatments 
on public lands to protect structures on adjacent private lands 
(Lettman et al. 2009, pp. 33-34; Azuma et al. 2013, pp. 1-2). 
Development of Federal forest lands in California and Oregon, however, 
is expected to be limited given past history (e.g. Lettman et al. 2011, 
p. 11 for Oregon) and the management mandates of the land management 
agencies.
    Based on the analysis contained within the Species Report and 
summarized above, and similar to the vegetation management discussion 
above, we estimate that development has a low impact on the loss, 
degradation, or fragmentation of suitable coastal marten habitat across 
the range of the DPS both currently and into the future, and thus does 
not rise to the level of a threat. If development occurs, the frequency 
and amount of habitat impacted may be greater in the coastal central 
Oregon population area as opposed to the other two population areas due 
to a larger percentage of privately-owned timber lands within the 
coastal central Oregon population area. However, as exhibited over the 
past 30 years, any loss is expected to be small.

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

Trapping
Trapping for Fur
    Historical unregulated fur trapping (prior to the 1930s) of coastal 
martens is considered by researchers as the likely cause of the marked 
contraction in coastal marten distribution. Legal marten fur trapping 
in coastal northern California ended in 1946. However, fur trapping 
remains legal and has continued in Oregon, and the number of martens 
harvested in coastal Oregon counties has declined since the 1940s 
(Zielinski et al. 2001, p. 482), although it is not known whether 
trapping effort remained unchanged over this time period. By the 1970s, 
martens were considered rare along the Oregon coast (Zielinski et al. 
2001, p. 483; Mace 1970, pp. 13-14; Maser et al. 1981, pp. 293-294). A 
total of 36 martens were harvested within coastal Oregon counties 
between 1969 and 1995 (Verts and Carraway 1998, p. 409). This harvest 
level excludes Lane and Douglas Counties because a substantial area of 
these counties is outside the DPS and fur trapping is only reported at 
the county level. The most recent data indicate that three coastal 
martens were trapped within coastal Oregon during the 2013 fur trapping 
season (Oregon Department of Fish and Wildlife, unpublished data). 
Overall, based on these data, the number of martens trapped in coastal 
Oregon has averaged fewer than two animals a year in recent decades. 
The fur trapping effort for martens in Oregon is relatively minimal; 
the Oregon Department of Fish and Wildlife reports that few trappers, 
generally from 4 to 8, trap for marten anywhere in the State in any 
given year. Most recent harvests of martens are from the Cascades and 
Blue Mountain Ranges; harvest of martens in the Coast Range is 
extremely rare (Hiller 2011, p. 17). Any potential population impacts 
of removing individual coastal martens as a result of fur trapping are 
difficult to estimate due to a lack of population size estimates in 
both Oregon population areas. The best available data indicate, 
however, that relatively few martens are removed from coastal 
populations as a result of fur trapping in Oregon, and we have no 
evidence to suggest that these populations may be in decline as a 
consequence of fur trapping.
    Based on the analysis contained within the Species Report and 
summarized above, we consider the legal fur trapping of coastal martens 
as having no overall impact to the population in coastal northern 
California, as there is no legal fur trapping for martens in that 
State. Fur trapping effort for martens in Oregon is relatively minimal, 
and most martens harvested are not trapped in the coast ranges. We 
estimate a low- to medium-level of impact to the two extant populations 
in coastal Oregon, reflecting the uncertainty regarding the size of 
those populations. We estimate that the impacts of fur trapping on 
coastal martens in Oregon will continue at a similar level, both 
currently and into the future, because the best available data do not 
suggest that either fur trapping effort or impacts are likely to 
change. Additionally, of note for California, we expect that nearly all 
coastal martens that are accidentally captured in box traps (body-
gripping traps are illegal in California) set for other furbearer 
species, or that are live-trapped for research purposes, will be 
released unharmed. As a result of this best available information for 
Oregon and California, we have determined that fur trapping, overall, 
does not have a significant population-level impact across the DPS's 
range and does not rise to the level of a threat.
Trapping for Research Purposes
    Based on the analysis contained within the Species Report, we 
consider the potential impacts of live-trapping and handling for 
research purposes on coastal marten populations as discountable. We 
came to this conclusion based on the limited distribution of marten 
research projects in the three extant population areas (currently only 
a single project in the western half of the coastal northern California 
population area where no martens were injured or killed during live-
trapping), and based on the strict trapping and handling protocols that 
must be adhered to by coastal marten researchers to ensure the safety 
of study animals. Available information does not suggest that there 
would be any change to the level of anticipated impacts of live-
trapping and handling for research purposes into the future, and, 
therefore, we find that the potential impacts to the coastal marten 
from trapping for research purposes do not rise to the level of a 
threat.

Factor C--Disease or Predation

Disease
    Numerous pathogens (e.g., canine distemper, canine parvovirus, 
toxoplasmosis) are known to cause severe disease in mustelids. Infected 
domestic dogs that are allowed to roam within an extant marten 
population area could expose martens to lethal pathogens. Fur trappers 
could capture an infected carnivore (e.g., marten, fisher, gray fox, 
bobcat) and inadvertently spread the disease to martens through 
contaminated traps. Marten researchers could also transfer lethal 
pathogens within and between extant population areas if traps and 
track-plate boxes are not disinfected after exposure to any carnivore 
species, including coastal martens.
    An outbreak of a lethal pathogen within any of the three extant 
coastal marten populations could occur. Several serious pathogens have 
been detected in the related fisher less than 9 km (5.6 mi) from the 
nearest verifiable marten detection within the coastal northern 
California population (Brown et al. 2008, entire), suggesting that 
martens could be exposed by infected juvenile fishers that disperse 
from their natal area into the coastal marten population area. However, 
despite possible exposure to pathogens, no outbreaks of

[[Page 18759]]

diseases have been detected in coastal martens, and we have no evidence 
to suggest that disease is currently present in any of the coastal 
marten populations.
    The best available data do not indicate that disease has impacted 
coastal martens at any point in time in the past or currently. The 
prevalence of past exposure to lethal pathogens within the coastal 
northern California population and the coastal Oregon populations has 
not been demonstrated through a serosurvey (i.e., a screening test of 
the serum of a marten to determine susceptibility to a particular 
disease). Additionally, if the known extant populations are disjunct 
from one another, as suggested by Slauson and Zielinski (2009, pp. 35-
36), this would be beneficial in terms of reducing the ease of 
transmission of disease between the populations, should an outbreak 
occur. Thus, at this time, the best available data do not indicate that 
a disease outbreak has had, or is likely to have, a significant 
population-level effect on coastal martens.
    In sum, there are currently no indications of disease in coastal 
marten populations. If an outbreak of a serious disease should occur, 
it could have a significant impact on the affected population. However, 
based upon the best available scientific and commercial data as 
presented in the Species Report and summarized here, there is a low 
probability that a disease outbreak may occur. We anticipate that if 
there should be an outbreak, it will likely have a low effect on all 
three coastal marten populations combined, as the distance between them 
makes it unlikely that the effects of such an outbreak would spread. 
Thus, we have determined that disease has a low-level population impact 
across the coastal marten's range and, therefore, does not rise to the 
level of a threat currently or into the future.
Predation
    Predation is a natural ongoing source of mortality for the coastal 
marten and would not be expected to negatively impact the viability of 
marten populations in coastal Oregon and coastal northern California 
unless annual predation rates, combined with all other mortality 
sources, exceed annual juvenile coastal marten recruitment rates 
(estimated at 50 percent for the coastal marten; Slauson et al., In 
prep.(a)). At this time, the only documented coastal marten predators 
are bobcats (Slauson et al. 2014, unpubl. data). However, additional 
predator species have been documented for other marten species and 
populations:
    (1) Strickland et al. (1982, p. 607) summarized reports of American 
martens being preyed upon by coyotes, fishers, red foxes, cougars, 
golden and bald eagles (Aquila chrysaetos, Haliaeetus leucocephalus), 
and great horned owls (Bubo virginianus).
    (2) Bull and Heater (2001a, p. 3) conducted a study in northeastern 
Oregon and documented 18 martens (i.e., Martes caurina vulpina) killed 
by predators: 44 percent by bobcats, 22 percent by raptors, 22 percent 
by other martens, and 11 percent by coyotes.
    Historical coastal marten predation rates are unknown, although the 
historical assemblage of predator species was likely similar to the 
current assemblage. It is possible that human-caused changes in 
vegetation composition, vegetation distribution, and extensive road 
building over time have increased predator densities and distribution 
within the range of the coastal marten. These changes in vegetation and 
infrastructure provide more access and avenues in which predators can 
exploit their prey base, especially in forested areas that were once 
undisturbed with extensive shrub cover for prey, such as martens, to 
escape or find shelter. For example, in coastal northern California, 
fisher and gray fox have both maintained their interior distributions 
but appear to have expanded their distributions in coastal redwood 
forest habitat concurrently with the dramatic decline in the 
distribution of coastal martens (Slauson and Zielinski 2007, p. 242). 
Another recent study within coastal northern California suggests that 
bobcats and gray foxes frequent roads in forests dominated by redwoods 
(Slauson and Zielinski 2010, pp. 77-78); the same is likely true for 
other forest types throughout the DPS's historical range in coastal 
Oregon and coastal northern California, but has not been confirmed. 
Slauson and Zielinski (2010, pp. 77-78) indicate that roads may be 
facilitating the presence and abundance of these predator species in 
dense-shrub landscapes and increasing the risk of intraguild predation 
on coastal martens. Therefore, past logging practices that reduced the 
complexity of the herb and shrub layers, in combination with existing 
roads, may have facilitated an increase in the distribution of 
predators within the range of coastal marten, thus potentially 
increasing the likelihood that coastal martens could encounter a 
predator.
    Predation of coastal martens has been studied recently. Since the 
fall of 2012, researchers have radio-tracked up to 23 coastal martens 
within the western portion of the coastal northern California extant 
population area to determine survival rates and cause of death. Data 
indicate a total of nine coastal marten mortalities, all killed by 
bobcats (Slauson et al. 2014, unpubl. data). Although these data would 
appear to indicate a 39 percent annual mortality rate, the annual 
mortality rate was estimated to be 33 percent due to several martens 
tracked for more than a year that were later found dead (Slauson et al. 
2014, unpubl. data). The mortalities have also occurred within areas 
where bobcats are considered more abundant and fishers have been 
documented, particularly where extensive logging and road building 
within suitable coastal marten habitat have occurred (Slauson 2014, 
pers. comm.). No other records of coastal marten predation have been 
documented nor conducted, including within coastal Oregon.
    Predation is identified as a natural stressor (i.e., part of the 
natural condition in which the coastal marten has evolved). Human 
activities (such as vegetation management and road building) may 
increase the abundance and distribution of predators within coastal 
marten home ranges. The preliminary home ranges of all nine dead 
coastal martens mentioned above contained relatively large amounts of 
recently logged forest, compared with the home ranges of radio-collared 
coastal martens that are still alive (Slauson 2014, pers. comm.), 
suggesting that disturbed areas may result in greater predation rates 
or that undisturbed areas, which harbor suitable habitat features for 
escape from predators, are likely preferred. In addition, all nine dead 
coastal martens were found within 100 m (328 ft) of a road. As 
described in the ``Population Biology and Dynamics'' section of the 
Species Report (Service 2015, p. 12), Slauson et al. (In prep.(a)) 
estimated annual juvenile coastal marten survival at 50 percent, which 
suggests that the observed 33 percent annual mortality rate of coastal 
martens from predation may be sustainable.
    The population-level impact of predation within the three coastal 
marten extant population areas is currently unknown. Data are available 
only for the coastal northern California population where a sample of 
23 individuals were radio-tracked and 9 of those were found predated 
upon by bobcats, indicating a 33 percent predation rate (Slauson et al. 
2014, unpubl. data). Similar information does not exist for the Oregon 
populations. However, the best available scientific and commercial data 
indicate that predation is occurring to an unknown

[[Page 18760]]

degree as an ongoing natural process across the range of the DPS.
    As noted above, a 33 percent annual predation rate is expected to 
be sustainable when compared with an annual juvenile coastal marten 
survival rate of 50 percent; thus, predation would not likely result in 
a population-level impact. Therefore, based on the best available data, 
we find that predation has a low-level population impact for all three 
extant coastal marten populations. The best available data indicate 
that predation is a natural process and the level of predation is not 
expected to increase in the future. Based on the analysis contained 
within the Species Report and summarized above, we have determined that 
predation does not rise to the level of a threat, given that it is a 
natural phenomenon and appears to be occurring at a sustainable level.

Factor D--The Inadequacy of Existing Regulatory Mechanisms

    Existing regulatory mechanisms that affect coastal martens include 
laws and regulations promulgated by the Federal and individual State 
governments. Federal and State agencies manage approximately 31 and 5 
percent, respectively, of the lands within the coastal marten's range, 
including a total of approximately 57 percent (13,388 km\2\ (5,169 
mi\2\)) of the currently available suitable habitat (high, medium, and 
low quality) throughout the range of the coastal marten (see Table 8.2 
in the Species Report (Service 2015, p. 37)). Tribal governments, as 
sovereign entities, have their own system of laws and regulations on 
tribal lands. Principal stressors acting on coastal martens for which 
governments may have regulatory control include injury or mortality due 
to fur trapping, habitat modification or loss, and legal uses of 
pesticides, including anticoagulant rodenticides (ARs). These 
regulations differ among government entities, are explained in detail 
in the Species Report (Service 2015, pp. 78-96), and are summarized 
below.
Federal
    All Forest Service and BLM lands within the range of the coastal 
marten are managed under the NWFP, which was adopted in 1994, to guide 
the management of 97,124 km\2\ (37,500 mi\2\) of Federal lands in 
portions of western Washington, Oregon, and northwestern California. 
The NWFP amends the management plans of National Forests and BLM 
Districts within the range of the northern spotted owl (Strix 
occidentalis caurina), representing a 100-year strategy intended to 
provide the basis for conservation of the northern spotted owl and 
other late-successional and old-growth forest-associated species 
(Forest Service and BLM 1994a, 1994b). This regional plan provides for 
retention and recruitment of older forests, and provides for spatial 
distribution of this type of habitat that will benefit late-
successional forest-dependent species, including the coastal marten. 
The amount of late-successional coniferous habitat on Federal lands 
removed since implementation of the plan is substantially lower than 
pre-implementation levels (Kennedy et al. 2012, p. 128). Activities 
such as timber harvest and thinning, fuels reduction treatments, and 
road construction (see ``Vegetation Management'' and ``Development'' 
under Factor A, above) may occur in certain areas known as matrix lands 
(i.e., limited areas delineated specifically to allow for programmed 
future timber harvest), which may result in some reduction of habitat 
and habitat connectivity for the coastal marten. However, the future 
loss, degradation, or fragmentation of suitable coastal marten habitat 
on Federal lands from these activities is expected to be low given the 
limited amount of matrix land allocation. Future increases in the 
amount and distribution of forest habitat suitable for coastal martens 
is expected to occur either through ingrowth in Federal Reserves, or 
through forest management activities designed to accelerate the 
development of late-seral characteristics within the coastal marten's 
range.
    The coastal marten is currently treated differently on Federal 
lands in Oregon as compared to California. In Oregon, the coastal 
marten is not considered a sensitive species on Forest Service and BLM 
lands. However, the Forest Service (Region 6) has added the marten to 
its draft sensitive species list that is expected to be finalized in 
2015 (U.S. Department of Agriculture, Forest Service 2014, p. 5), and 
BLM (Medford and Roseburg Districts) is also working to add the marten 
to its sensitive species lists (Hughes 2015, pers. comm.). In 
California, the coastal marten is a sensitive species on Forest Service 
lands, but not on BLM lands. Federal protections afforded the coastal 
marten as a sensitive species on Forest Service lands in California 
largely depend on best management practices and conservation efforts 
outlined in their Land and Resource Management Plans (LRMPs), and on-
site-specific project analyses and implementation.
    Potential exposure of coastal martens to ARs has not yet been 
studied, but to date we have incidental evidence of sublethal exposure 
in at least one individual (see ``Exposure to Toxicants'' under Factor 
E, below). The use of rodenticides is regulated under the Federal 
Insecticide, Fungicide, and Rodenticide Act of 1947 (7 U.S.C. 136 et 
seq.), via the registration of labels by the U.S. Environmental 
Protection Agency. Each label describes the permitted use for an 
individual rodenticide product and must be supported by rigorously 
collected and analyzed efficacy and environmental safety data. However, 
it is not clear how well those regulations prevent wildlife (including 
coastal martens) exposure to legal uses of these rodenticides. Coastal 
martens may also be exposed to rodenticides used illegally in the form 
of rodenticide applications on illegal marijuana grow sites. Law 
enforcement efforts occur in both Oregon and California in an attempt 
to eradicate suspected illegal marijuana grow sites, but it is unknown 
how effective such measures are at reducing the exposure of martens to 
rodenticides. At this time, as described below, the best available data 
do not indicate population- or rangewide-level impacts to coastal 
martens from legal or illegal use of rodenticides.
    The Forest Service has extensive policy on the use of rodenticides 
(Forest Service Manual 2670.32), and the Forest Service Manual (Forest 
Service 2005, Chapter 2600) contains legal authorities, objectives, 
policies, responsibilities, instructions, and guidance needed on a 
continuing basis by Forest Service line officers and primary staff to 
plan and execute assigned programs and activities. In addition, BLM 
policy (BLM Manual 9011-Chemical Pest Control) regulates the use of 
rodenticides and other pesticides on their ownership. Queries to the 
BLM and Forest Service in Oregon confirm they do not use anticoagulant 
rodenticides on their ownership, although some use of strychnine for 
rodent control is employed on Forest Service land (Standley 2013, pers. 
comm.; Bautista 2013, pers. comm.).
States of Oregon and California
    Forest practice rules vary greatly between Oregon and California, 
with no explicitly stated coastal marten protections specified in 
either State. However, retention of some number of snags and green 
trees in harvest units is a ubiquitous requirement in managed forests 
throughout the range of the coastal marten (State, Federal, and private 
lands) (e.g., Oregon forest practice rules (Oregon Administrative Rules 
(OAR) Chapter 629, Division 600); CAL FIRE forest practice rules (Title 
14, California Code of Regulations, Chapters

[[Page 18761]]

4, 4.5, and 10; Forest Service and BLM 1994a, 1994b)). The coastal 
marten is not listed under the California Endangered Species Act (CESA) 
or as a State ``fully protected'' species and thus does not receive 
protections available under those statutory provisions. In terms of 
effects to coastal marten habitat or incidental harm to coastal martens 
from timber harvesting or other types of land-disturbing projects, the 
State of California has existing regulations that act in combination to 
disclose, avoid, or mitigate environmental degradation, the latter two 
situations of which could potentially result in benefits to coastal 
marten habitat. Cumulative effects analyses for listed and non-listed 
species, such as coastal marten, are required in both the California 
Environmental Quality Act (CEQA) and the California forest practice 
rules.
    Structures that are retained (e.g., some level of snags and green 
trees) under existing forest practice rules typically do not meet the 
minimum size used by coastal martens (Schmidt 2014, pers. obs.; Slauson 
2014, pers. obs.). Where these features are large enough, they may 
provide future denning and resting sites provided they have the 
appropriate structural attributes (such as cavities and large limbs) 
and the surrounding forest is allowed to develop the necessary canopy 
cover, dense shrub understory, and prey base to support coastal martens 
in the long term. Short rotations of industrial forest management 
rarely allow this to happen, as compared to areas where management is 
for longer rotations or designed to develop older stands (e.g., old-
forest structure management on Oregon State Forests) that retain these 
legacy features that may facilitate coastal marten habitat development.
    Protection measures for riparian areas are also a widespread 
standard on managed forests throughout the range of the coastal marten, 
with larger buffers and more stringent timber retention requirements 
typically provided on Federal and State lands as compared to private 
lands. Retention areas to meet other management goals are also found 
across ownerships (e.g., anchor habitats on Oregon State Forests, 
occupied site buffers on multiple ownerships, Watercourse and Lake 
Protection Zones on private land in California). Although many of these 
retained areas are not large enough to support a coastal marten home 
range, they do provide patches of structural features that may allow 
coastal marten movement across the landscape and facilitate dispersal 
between larger blocks of coastal marten habitat. This may be 
particularly valuable where State lands lie between large blocks of 
Federal lands managed as late-seral habitat. Additionally, the Oregon 
Department of Forestry calls for managing 30 to 50 percent of their 
State Forests in northwest Oregon for layered and old-forest structural 
conditions such as larger trees, multiple canopy layers, diverse 
understories and shrub layering, and diverse structural features such 
as downed wood and snags (ODF 2010, pp. 4-48, C-1 to C-24). These lands 
represent a small proportion of currently occupied habitat and are 
mostly located outside of existing coastal marten population areas; 
however, these areas may benefit coastal martens in the future as they 
are allowed to develop into a structural condition more suitable to 
martens.
    Coastal martens can be legally harvested/trapped for fur in Oregon 
but not in California (see ``Trapping'' under Factor B, above). Within 
Oregon, coastal martens are listed (by the Oregon Department of Fish 
and Wildlife) as a sensitive species in the vulnerable category and as 
a species of conservation concern, but neither of these designations 
has associated regulatory mechanisms. Rather, these designations are 
used to encourage voluntary actions to improve a taxon's status or 
prevent population declines. Within California, coastal martens may not 
be intentionally harvested or trapped for fur or otherwise killed in 
California; although injury or mortality may occur when coastal martens 
are incidentally captured in traps set for other species, we expect 
incidental captures to be released unharmed. The use of body-gripping 
traps is prohibited and enforced in California, but injury or mortality 
of coastal martens is likely to occur during illegal fur trapping using 
the banned body-gripping traps. The extent of illegal fur trapping and 
mortality of coastal martens in Oregon and California is unknown. In 
general, legal trapping (such as that for research) is unlikely to 
result in injury or mortality to coastal martens because of the 
mandatory use of live traps and strict trapping and handling 
procedures.
Summary of Factor D
    Overall, existing Federal and State land-use plans include some 
general conservation measures for northern spotted owl habitat that are 
not specific to coastal martens but nonetheless provide a benefit to 
the coastal marten, for example through the maintenance and recruitment 
of late-successional forest and old-growth habitat. Most management 
plans address structural habitat features (e.g., snags or downed wood 
retention) or land allocations (e.g., Oregon Department of Forestry's 
no-cut riparian buffer; NWFP's protections of a network of late-
successional forest habitat connected by riparian reserves) that 
contribute to the coastal marten's habitat. These land-use plans are 
typically general in nature and afford relatively broad latitude to 
land managers, but with explicit sideboards for directing management 
activities. Federal regulatory mechanisms have abated the large-scale 
loss of late-seral coniferous forest habitat. Much of the land in 
Federal ownership across the range of the coastal marten is managed for 
interconnected blocks of late-successional forests that are likely to 
benefit martens. Timber harvest has been substantially reduced on 
Forest Service and BLM lands within the NWFP area, and existing 
management is designed to maintain or increase the amount and quality 
of late-successional or old-growth forest that provides marten habitat 
and aids in connecting populations. Management of State lands for 
scattered parcels of older forest or habitat retention for other late-
successional species may also facilitate coastal marten movements 
across the landscape or provide future habitat as some areas are 
allowed to develop into older stands. Outside of public (State and 
Federal) ownership, forest practice rules provide no explicit 
protection for martens and limited protections for habitat of value to 
martens. While some structural retention and limited buffers may retain 
structural features desirable for martens on private lands, the short 
harvest-rotation periods reduce the likelihood that the surrounding 
stand will develop to a condition that makes these features suitable 
for long-term use by martens.
    Based on the analyses contained within the Species Report (Service 
2015, pp. 81-94) and summarized above on the existing regulatory 
mechanisms for the coastal marten, we conclude that the best available 
scientific and commercial information does not indicate that the 
existing regulatory mechanisms are inadequate to address impacts to 
coastal martens from the identified stressors.

Factor E--Other Natural or Manmade Factors Affecting the Continued 
Existence of the Species

Collision With Vehicles
    Collision with vehicles is a known source of mortality for coastal 
martens currently and is expected to continue into the future, given 
the presence of roads within the range of the DPS. A low density of 
roads with heavy traffic traveling at high speeds (greater than 45 
miles per hour) and infrequent reports of road-killed martens within 
all three

[[Page 18762]]

extant population areas suggest that few martens die from vehicle 
collisions each year.
    No coastal marten road kill mortalities have been reported recently 
(since 1980) from within the coastal southern Oregon and coastal 
northern California population areas, both of which are areas that do 
not contain long segments of heavily used highway (although it is 
possible that road kill on any light-use roads in remote areas may not 
be discovered by humans before being consumed as carrion). A total of 
14 coastal marten mortalities have been documented from vehicle 
collision since 1980 (over a 34-year period) within or near the coastal 
central Oregon population area, suggesting a low annual mortality rate 
from vehicle collisions. Collisions with vehicles were and continue to 
be expected within the coastal central Oregon population because of the 
presence of U.S. Highway 101 within this population.
    We expect that in the future a small number of coastal martens will 
be struck by vehicles, especially dispersing juvenile coastal martens 
that must reach unoccupied suitable habitat for establishment of a home 
range. However, the best available information does not suggest any 
significant increases in vehicular traffic or new highways (consistent 
with the information available on potential development-related impacts 
(see ``Development'' under Factor A, above)) to be built in areas where 
martens occur. Therefore, we conclude the impact of vehicle collisions 
on coastal martens to continue at similar levels into the future. Any 
potential population impacts from individual coastal marten mortalities 
as a result of collisions with vehicles are difficult to estimate; we 
have no evidence of mortalities due to collisions with vehicles in the 
coastal northern California or coastal southern Oregon populations, and 
lack any population size estimate for the coastal central Oregon 
population area where some mortalities have been documented over an 
extended period of time. The best available data indicate, however, 
that across the DPS relatively few coastal martens are killed as the 
result of collisions with vehicles. Based on the information presented 
above and in the Species Report (Service 2015, pp. 52-53), we find that 
collision with vehicles presents a low-level impact on all three 
coastal marten populations (i.e., impacts to individual coastal martens 
as opposed to populations); therefore, this stressor does not rise to 
the level of a threat.
Exposure to Toxicants
    An emerging stressor to coastal martens is the widespread use of 
anticoagulant rodenticides (ARs) and other pesticides (e.g., 
organophosphates, carbamates, or organochlorines) at both legal and 
illegal marijuana grow sites, and the potential individual- and 
population-level impacts to species, including coastal martens, that 
are exposed to toxicants at these sites. We note that recent efforts to 
determine the prevalence of ARs in carnivore populations have focused 
on fisher populations in California due to the conservation status of 
that species and because marijuana grow sites are common in California. 
As information specific to coastal martens is largely lacking, for the 
purposes of the analysis in our Species Report (Service 2015, pp. 54-
61), we examined this fisher information to help evaluate the potential 
impacts ARs might have on coastal marten populations in coastal 
northern California and coastal Oregon.
    Anticoagulant rodenticides were created to kill small mammals 
considered pests, including commensal rodents such as house mice (Mus 
musculus), Norway rats (Rattus norvegicus), and black rats (R. rattus) 
in and around residences, agricultural buildings, and industrial 
facilities, and agricultural pests such as prairie dogs (Cynomys sp.) 
and ground squirrels (Spermophilus sp.) in rangeland and near crops. 
Anticoagulant rodenticides bind to enzymes responsible for recycling 
vitamin K, thus impairing the animal's ability to produce several key 
blood clotting factors (Berny 2007, p. 97; Roberts and Reigart 2013, 
pp. 173-174).
    Anticoagulant rodenticide exposure is manifested by such conditions 
as bleeding nose and gums, extensive bruises, anemia, fatigue, and 
difficulty breathing. Anticoagulants also damage the small blood 
vessels, resulting in spontaneous and widespread hemorrhaging. There is 
often a lag time of several days between ingestion and death, if lethal 
doses are ingested (Berny 2007, pp. 97-98; Roberts and Reigart 2013, 
pp. 174-175). Evidence from laboratory and field studies for several 
mammalian and avian species suggests that various pesticide (including 
rodenticide) exposures:
    (1) Reduce immune system function (Repetto and Baliga 1996, pp. 17-
37; Li and Kawada 2006, entire; Zabrodskii et al. 2012, p. 1);
    (2) Are associated with a higher prevalence of infectious disease 
(Riley et al. 2007, pp. 1878, 1882; Vidal et al. 2009, p. 270);
    (3) Cause transient hypothermia (Ahdaya et al. 1976, entire; Gordon 
1984, p. 432; Grue et al. 1991, pp. 158-159), which may contribute to 
an increase in mortality rates (Martin and Solomon 1991, pp. 122,126); 
or
    (4) Possibly impair an animal's ability to recover from physical 
injury (Erickson and Urban 2004, pp. 90, 100, 184, 188, 190-191).
    Exposure to ARs, resulting in death in some cases, is documented in 
many mammalian predators (e.g., Alterio 1996, entire; Shore et al. 
1999, entire; Riley et al. 2007, entire; Gabriel et al. 2012, entire; 
Quinn et al. 2012, entire), but such information is unavailable for 
coastal martens. However, there is wide variability in lethal and 
sublethal levels of ARs exhibited among and within taxonomic groups 
(Gabriel et al. 2012, p. 11), and it is unknown if stressors or 
injuries could predispose all species to elevated mortality rates 
(e.g., Gabriel et al. 2012, p. 10 for fishers). In one California study 
of two fisher populations, the majority (84 percent) of fishers 
(closely related to martens) tested positive for the presence of ARs, 
but at sublethal levels (Thompson et al. 2013, p. 6; Gabriel et al. 
2012, p. 5). Additionally, several fishers have recently been confirmed 
to have died from acute poisoning from ARs on the Hoopa Reservation 
(Gabriel et al. 2012), which is located less than 9 km (5.6 mi) south 
of the coastal marten's extant population area in coastal northern 
California. However, Gabriel et al. (2012, p. 6) determined that AR 
exposure was the direct cause of death for only a small proportion (4 
of 58 individuals found dead within 2 isolated California populations) 
of those fishers examined.
    Little information exists specific to coastal marten exposure or 
response to ARs. Coastal martens within the California population and 
likely the coastal Oregon populations may be exposed to ARs currently 
or in the future in those areas where marijuana grow sites are located 
(which currently is known to be a fraction of the coastal marten's 
range) based on: (1) The proximity of the closely related fisher with 
confirmed exposure to ARs, including in areas as close as 9 km (5.6 mi) 
from the coastal northern California population; (2) the broad use of 
ARs at illegal marijuana cultivation sites, which have been documented 
to occur within or adjacent to portions of both the marten's coastal 
northern California and coastal southern Oregon population areas; and 
(3) the potential continued use of ARs at legal grow sites and other 
areas within the range of the coastal marten where agricultural 
pesticide use

[[Page 18763]]

occurs. Although the presence or use of ARs is documented in many areas 
throughout coastal northern California and into portions of Oregon 
(Higley et al. 2013, p. 2; Oregon High Intensity Drug Trafficking Area 
2013, entire), to date, only one record of a positive exposure exists 
within the range of coastal martens that demonstrates exposure to ARs. 
This information was obtained from non-related, coincidental research 
occurring in the coastal northern California extant population area in 
2014; of six coastal martens assessed, one tested positive for AR 
exposure with a sublethal concentration (Slauson 2014, unpubl. data). 
The individual that tested positive was confirmed killed by a bobcat. 
It is unknown whether the sublethal dose of ARs may have predisposed 
that coastal marten to predation. This information about potential 
exposure of coastal martens to ARs was collected on private lands and 
involved a small sample size (six coastal marten individuals) in one 
portion of the coastal northern California extant population area; 
thus, it is not necessarily representative of the levels of exposure 
throughout other land ownership areas within the remainder of the DPS. 
The sublethal AR exposure of this single coastal marten is the only 
data available to us regarding potential exposure of coastal martens to 
ARs; the best available information does not indicate any population- 
or rangewide-level impacts of AR exposure on coastal martens.
    Overall, illegal and legal marijuana cultivation sites (and use of 
ARs and other pesticides) are present within or near all three coastal 
marten populations, although the probability of exposure varies between 
them. At this time we estimate that the prevalence of illegal marijuana 
cultivation sites (based on data associated with eradicated cultivation 
sites) occurs within approximately 5 percent of the coastal central 
Oregon population area, 25 percent of the coastal southern Oregon 
population area, and 40 percent of the coastal northern California 
population area (Service 2014, unpubl. data). However, the incidence of 
toxicant exposure that may result for coastal martens and the potential 
population-level effects are largely unknown given testing for exposure 
to ARs began only recently. We note significant uncertainty as to the 
severity of impact that this stressor may have at the population- and 
rangewide levels on coastal marten given that the best available data 
are minimal regarding potential exposure to this stressor and any 
consequent effects on coastal martens at this time, including the lack 
of information regarding potential sublethal effects. There are few 
samples to fully determine coastal marten exposure rates to ARs, and no 
tests on martens to determine sublethal exposure rates and effects. The 
recent legalization of marijuana in the State of Oregon adds an 
additional element of uncertainty to evaluation of this stressor, as it 
is unknown whether or how this may potentially affect exposure rates 
(for example, whether there may be a trend toward indoor grow 
operations, which would potentially reduce exposure of wildlife to 
ARs). Based on the analysis contained within the Species Report and 
summarized above, we find the population-level impact from exposure to 
toxicants to be low both currently and into the future, although a 
higher (medium-level) impact may occur for the coastal northern 
California population as a result of higher prevalence of illegal 
marijuana cultivation sites. The best available information does not 
suggest that these impacts rise to the level of a threat, primarily 
based on the available information on levels of known marten exposure 
to ARs and lack of evidence that ARs are having a population-level 
effect.
Small and Isolated Population Effects
    Small, isolated populations are more susceptible to impacts 
overall, and relatively more vulnerable to extinction due to genetic 
problems, demographic and environmental fluctuations, and natural 
catastrophes (Primack 1993, p. 255). That is, the smaller a population 
becomes, the more likely it is that one or more stressors could impact 
a population, potentially reducing its size such that it is at 
increased risk of extinction. We therefore evaluated information 
suggesting that the currently known populations of coastal martens may 
be small or isolated from one another to the degree that such negative 
effects may be realized in the DPS.
    The best available data suggest coastal marten distribution has 
contracted markedly in California and southern Oregon since the early 
20th century. At present there are three known extant populations of 
coastal martens in California and Oregon; however, much of coastal 
Oregon has not been systematically surveyed. Of these known 
populations, the coastal northern California population is the only 
population for which size estimates are available. Based on multi-state 
occupancy modeling, Slauson et al. (2009b, p. 13) estimated that the 
abundance of coastal martens in the coastal northern California 
population area is low (i.e., fewer than 100 individuals in 2008). 
Comparing areas sampled in 2008 to those sampled in 2000 to 2001, 
sample unit occupancy had declined by an estimated 42 percent (Slauson 
et al. 2009b, p. 10). Whether this change may have been part of a 
natural population fluctuation or was related to human-caused factors 
is unknown (Slauson et al. 2009b, p. 14). Although small in size, 
preliminary occupancy estimates for 2012 (which are unchanged from 
2008) suggest no further changes in marten population abundance 
(Slauson et al. 2014, unpubl. data).
    The abundance and trend of coastal marten populations in coastal 
Oregon is unknown; standardized survey efforts for martens in central 
and southern Oregon began in 2014. In the coastal central Oregon 
population area, at least one marten was detected in 2014, and six 
martens have been detected in 2015 in the first weeks of surveys 
(Moriarty 2015, pers. comm.). In addition, surveys just beginning in 
southern coastal Oregon have yielded a marten detection (Moriarty 2015, 
pers. comm.). Surveys are continuing at the time of publication of this 
document.
    Slauson and Zielinski (2009, p. 36) describe the three known extant 
coastal marten populations as disjunct. Verified marten detections have 
clustered into the three extant population areas recognized in this 
document, which are geographically separated. The degree of functional 
connectivity between the known populations is not well understood due 
to insufficient survey effort in many areas, particularly in coastal 
Oregon (Service 2015, p. 29). There are some detections of martens 
occurring between the coastal northern California and coastal southern 
Oregon populations (Service 2015, p. 31, Figure 8.2(B)). Habitat 
modeling suggests connectivity of suitable habitat between these 
populations (Service 2015, pp. 25-26), and there are no known barriers 
to dispersal between them. Suitable habitat is more limited and of 
lower quality between the coastal southern Oregon and coastal central 
Oregon populations, but not entirely discontinuous (Service 2015, pp. 
25-26). Survey efforts have also been more limited in this area to date 
(Service 2015, p. 29). Marten surveys are largely lacking from coastal 
central and coastal northern Oregon, although habitat modeling suggests 
conditions suitable for additional martens that could support the 
existing known populations (Service 2015, p. 29-30, 34).

[[Page 18764]]

    Surveys designed to determine potential occupancy by coastal 
martens (for example, targeting areas of suitable habitat large enough 
to support multiple home ranges) may not necessarily detect animals 
moving between populations. Although not equivalent in function to 
large areas of contiguous habitat, fragmented patches of forest 
sufficient to provide corridors for dispersal of individuals can play 
an important role in maintaining assemblages of old-growth forest 
mammals (Perault and Lomolino 2000, pp. 418-419). The potential habitat 
connectivity between known populations of coastal martens and their 
capacity to travel long distances at least on occasion suggests that 
the geographically disjunct nature of coastal marten populations is not 
necessarily a barrier resulting in isolation. As described earlier, the 
majority of juvenile martens disperse relatively short distances from 
their natal areas, generally less than 15 km (9.3 mi) (Phillips 1994, 
pp. 93-94). The distance between known extant coastal marten 
populations exceeds the mean maximum juvenile dispersal distance for 
martens in general (15 km (9.3 mi); Phillips 1994, pp. 93-94). The 
distance between known extant populations exceeds this distance, but is 
within the maximum observed dispersal capability of martens, ranging 
from 40 to 80 km (25 to 50 mi) (Thompson and Colgan 1987, pp. 831-832; 
Broquet et al. (2006, pp. 1690, 1695), up to 149 km (92 mi) or greater 
(Slough 1989, p. 993; Kyle and Strobeck 2003, p. 61). The relatively 
continuous extent of some limited area of marten habitat, though much 
of it is low in quality, and dispersal capabilities of martens 
indicates that movement between coastal marten populations is possible, 
acknowledging that individuals seeking to traverse areas of 
regenerating forest face reduced probability of survivorship (Johnson 
et al. 2009, p. 3366). For this reason, areas that may provide for safe 
corridors of movement, such as riparian areas retained under State 
forest practice rules (see Factor D, above), may play an important role 
in facilitating connection between larger areas of suitable habitat for 
coastal martens.
    In most cases, genetic interchange need occur only occasionally 
between populations (a minimum of 1 migrant per generation, possibly up 
to 10) to offset the potential negative impacts of inbreeding (e.g., 
Mills and Allendorf 1996, entire; Wang 2004, entire). In addition, 
depending on population sizes and the distance between them, the 
ability of even a few individuals to move between population areas can 
preserve the potential for recolonization or augmentation (Brown and 
Kodric-Brown 1977, entire). Genetic evidence from studies of martens in 
fragmented landscapes suggests that despite separation of populations 
by large distances, up to several hundred kilometers, little genetic 
differentiation is observed (Broquet et al. 2006, p. 1690, citing Kyle 
and Strobeck 2003, pp. 60-61). Broquet et al. (2006, p. 1690) suggest 
this weak genetic structure is indicative of great dispersal capacity 
in martens, and their results suggest that a few successful long-
distance dispersers create enough gene flow in marten populations to 
significantly reduce genetic differentiation that might otherwise 
result from isolation by distance (Broquet et al. 2006, p. 1695).
    Based on all of these consideration, despite the relatively 
geographically disjunct nature of the known extant marten populations, 
we do not have evidence to suggest that the populations are likely 
entirely isolated from one another to the degree that we would expect 
the manifestation of significant negative effects that could 
potentially arise in small, isolated populations, such as inbreeding 
depression. We recognize that habitat quality and contiguity could be 
improved between the extant population areas, and indications are that 
habitat recruitment through management of Federal lands under the NWFP 
should contribute to improved connectivity. Despite room for 
improvement, at this point in time, the best available information 
suggests that the extant population areas are within the dispersal 
capabilities of martens and the habitat suitability model indicates 
some connectivity between populations, at least sufficient to provide 
for occasional genetic interchange. We note that more detailed 
information is needed regarding the size and demographics of coastal 
marten populations, as well as the capability of intervening areas of 
habitat to support dispersing individuals, in order to fully understand 
whether the known populations are faced with any challenges as a result 
of the present degree of connectivity between them.
    Although coastal martens are likely reduced in abundance or 
distribution relative to their historical numbers and range, there is 
no empirical evidence that any current populations of coastal marten 
are in decline. Based upon the analysis contained within the Species 
Report and summarized above, the best available information indicates 
that the coastal northern California population totals fewer than 100 
individuals (Slauson et al. 2009b, p. 13). Although small in size, the 
estimated number of individuals that comprise the coastal northern 
California population of martens appears to have remained the same in 
recent years based on survey data collected since 2008.
    Abundance and trend estimates are not available for the two coastal 
Oregon populations, so it is unknown whether these populations might be 
considered small. Coastal martens have likely been reduced in abundance 
relative to their historical numbers, although Zielinski et al. (2001, 
p. 487) suggest that out of the three west coast States, coastal 
martens are likely most common in Oregon. These researchers note, 
however, an inability to evaluate the status of martens in the coastal 
mountain ranges of central and northern Oregon due to insufficient 
historical or contemporary data (Zielinski et al. 2001, p. 486). Data 
from systematic surveys continue to be limited or nonexistent in 
coastal northern and coastal central Oregon, leading to an inability to 
determine population size, trend, or distribution in these areas at 
this time. However, as noted above, recently initiated surveys in 
coastal central and coastal southern Oregon did result in seven total 
detections of coastal martens in the first weeks of effort in 2015 
(Moriarty 2015, pers. comm.), and surveys are continuing at the time of 
this publication (Moriarty 2015, pers. comm.).
    The three known extant populations of coastal martens are disjunct. 
While this characteristic does have some potential negative effects 
(e.g., potential impacts from other stressors may be exacerbated), 
overall it places the DPS at a diminished risk of extinction due to 
small population size effects (known small population for coastal 
northern California and unknown for coastal Oregon populations) because 
it is unlikely that any stressor will simultaneously affect all three 
populations. In addition, although the populations may be 
discontinuous, we do not have evidence to suggest that populations are 
entirely isolated beyond the potential dispersal range known for 
martens such that negative small population effects are likely to be 
realized. Therefore, based on the best available data, we have 
determined that small or isolated population size effects do not rise 
to the level of a threat either currently or in the future.

Cumulative Effects

    We estimate the potential impact of each stressor described above 
acting alone on coastal marten individuals, populations, and suitable 
habitat. However, coastal marten populations and suitable habitat can 
also be affected

[[Page 18765]]

by all stressors acting together or some of the identified stressors 
acting together (particularly medium-level impacts, as described in 
detail in the Species Report and summarized above). The combined 
effects of those stressors could impact populations or suitable habitat 
in an additive or synergistic manner. Any given stressor could impact 
individuals, a portion of a population, or available suitable habitat 
to varying degrees or magnitude, and alone, a stressor may not 
significantly impact coastal martens or their habitat.
    Based on our analysis of all stressors that may be impacting 
coastal martens or their habitat, including, to be conservative, taking 
into account effects associated with potential small or isolated 
populations (noting that the coastal northern California population is 
known to be small and information is not available to indicate if the 
coastal Oregon populations may be small), it is likely that if any 
cumulative impacts occur, they would do so under the following three 
scenarios:
    (1) A projected increase in the frequency and size of wildfires 
within the coastal southern Oregon and coastal northern California 
portions of the DPS's range due to climate change model projections of 
a warmer, drier climate in the future, which could also change 
vegetation structure.
    (2) A potential increase in coastal marten mortality rates from 
predation, disease, fur trapping in Oregon, and collision with vehicles 
due to reduced marten fitness after sublethal exposure to toxicants 
found at marijuana grow sites, although levels of exposure remain 
unknown.
    (3) Increased coastal marten predation rates due to an increased 
abundance of intraguild predators (e.g., bobcats, fishers) resulting 
from vegetation management activities that improve habitat suitability 
for these marten predators by decreasing shrub densities.
    Here we consider the impacts of each of these potential cumulative 
effect scenarios:
    Models of climate change predict potential increases in wildfire 
frequency and size within the coastal southern Oregon and coastal 
northern California portions of the DPS. As described in our analysis 
in ``Wildfire'' under Factor A, above, we expect that wildfire impacts 
are likely to occur throughout the range of the coastal marten at a 
level similar to the historical impacts that have occurred within each 
extant population area between 1984-2012 (roughly 30 years), and we 
expect that fire frequency, size, and severity in the future will be 
fairly similar or slightly higher in some areas based on climate change 
projections. Based on these 30 years of data, we can reasonably 
estimate that these effects will continue with the same approximate 
level of impact throughout the DPS into the next 30 years, although 
they may be slightly higher in the coastal southern Oregon and coastal 
northern California population areas. Additionally, we do not have 
information that climate change will result in vegetation changes that 
will make significant portions of currently occupied coastal marten 
habitat unsuitable. Therefore, the best available data at this time do 
not suggest that the cumulative effects of wildfire and climate change 
rise to the level of a threat to the DPS overall for the following 
reasons:
    (1) Although climate change models generally predict warmer, drier 
conditions in the future, the coastal marten primarily inhabits forests 
that are relatively less vulnerable to such changes. The overall 
continued presence of relatively moist habitat conditions for coastal 
marten habitat, primarily along the western coast, including overall 
cooler, moist summer conditions, moderate the dry conditions that 
promote fire ignition and spread.
    (2) Moderate- and high-quality habitat for coastal martens has 
remained following recent large wildfires (i.e., wildfires that have 
burned at mixed severities (LANDFIRE 2008a; LANDFIRE 2008b; LANDFIRE 
undated(a))); these fires have not resulted in extensive stand-
replacement within the coastal marten's range.
    (3) Neither adverse changes to coastal marten habitat through 
potential vegetation changes nor the loss of habitat from future 
wildfires is expected to be significant, nor is the combined effect of 
these two potential stressors.
    Sublethal effects of anticoagulant rodenticides have been 
demonstrated for many species (see discussion in the Species Report 
(Service 2015, p. 57)), and can include reduced blood clotting 
abilities and excessive bleeding. Sublethal exposure to ARs has been 
shown to make individuals of non-mustelid mammals more susceptible to 
environmental stressors such as adverse weather, food shortages, and 
predation (Erickson and Urban 2004, p. 99; Jaques 1959, p. 851; Cox and 
Smith 1992, p. 169; Brakes and Smith 2005, p. 121; LaVoie 1990, p. 29), 
potentially predisposing individuals to death from other causes. 
However, there is wide variability in lethal and sublethal levels of 
ARs exhibited among and within taxonomic groups (Gabriel et al. 2012, 
p. 11), and it is unknown if stressors or injuries could predispose all 
species to elevated mortality rates (e.g., Gabriel et al. 2012, p. 10 
for fishers). While it is possible that these effects could occur for 
coastal martens, the best available data at this time do not support a 
conclusion that the cumulative effects of rodenticides (which may occur 
at relatively few sites within the extant population areas and thus 
reduce likelihood of exposure) combined with other environmental 
stressors rise to the level of a threat to the DPS overall. Relatively 
few marijuana grow sites have been found within the extant population 
areas (which reduce likelihood of exposure), there are too few samples 
to determine coastal marten exposure rates to ARs, and no tests have 
been conducted on martens to determine sublethal exposure rates and 
effects. Furthermore, none of the data available (related to exposure 
and potential lethal or sublethal effects) demonstrate an effect 
leading to current or future population declines.
    Vegetation management activities that reduce the shrub layer that 
coastal martens rely on could also provide increased suitable habitat 
for marten predators, such as bobcats, resulting in potential increased 
levels of predation on coastal martens. In general, however, we expect 
such vegetation management activities would be restricted primarily to 
private lands. As discussed above (see Summary of Species Information, 
above), the majority of the area known to be occupied by coastal 
martens is composed of Federal lands, and most of these Federal lands 
are in reserves managed under the standards and guidelines of the NWFP. 
As these areas are under management for the protection or enhancement 
of late-successional forest characteristics, we do not expect extensive 
management activities on these lands to reduce shrub densities and thus 
potentially result in increased abundance of intraguild predators. 
Reduced shrub densities as a result of vegetation management on private 
lands may pose an increased risk of predation to individual coastal 
martens seeking to disperse through such areas, which poses some 
challenges in terms of maintaining or developing connectivity between 
populations. Although a potential reduction in the complexity of herb 
and shrub layers on these private lands is likely to continue and thus 
potentially result in increased suitable habitat for marten predators, 
these vegetation changes are expected to be offset by the continued 
maintenance and enhancement of significant portions of suitable habitat 
on forested reserves throughout the range of the coastal marten. Thus, 
at this time, cumulative

[[Page 18766]]

effects of potential vegetation management activities and predation do 
not rise to the level of a threat to the DPS overall.
    In summary, the best available scientific and commercial data at 
this time do not show that combined impacts of the most likely 
cumulative impact scenarios are resulting in significant individual- or 
population-level effects to the coastal marten, including when taking 
into consideration small population size, where known. Although all or 
some of the stressors could potentially act in concert as a cumulative 
threat to the coastal marten, there is ambiguity in either the 
likelihood or level of impacts for the various stressors at the 
population or rangewide level, or the data indicate only individual-
level impacts. There is little doubt that coastal marten populations 
today are smaller and their range has been reduced compared to 
historical conditions, which potentially increases the vulnerability of 
the coastal marten to potential cumulative low- or medium-level 
impacts. However, the best available information does not provide 
reliable evidence to suggest that current coastal marten populations 
are experiencing population declines or further reductions in 
distribution, which would be indicative of such impacts. Thus, the best 
available scientific and commercial data do not indicate that these 
stressors (including consideration of effects associated with 
potentially small or isolated populations, to be conservative) are 
cumulatively causing now or will cause in the future a substantial 
decline of the total extant populations of the coastal marten across 
its range. Therefore, we have determined that the cumulative impacts of 
these potential stressors do not rise to the level of a threat.

Conservation Efforts

    The Humboldt Marten Conservation Group (HMCG) was formed in 2011, 
with the primary goal of developing a conservation assessment and 
strategy for the [then described] Humboldt marten subspecies (Martes 
americana humboldtensis) in coastal northern California. A memorandum 
of understanding (MOU) was signed on September 26, 2012, between the 
Service, Six Rivers National Forest, the U.S. Forest Service Pacific 
Southwest Research Station, Redwood National and State Parks, 
California Department of Fish and Wildlife (CDFW; formerly California 
Department of Fish and Game (CDFG)), California Department of Parks and 
Recreation (CDPR), the Yurok Tribe, and the Green Diamond Resource 
Company (Service 2012, entire). Each signatory party designated two or 
more members to provide input to the conservation assessment and 
strategy, and to guide future implementation of priority conservation 
actions, irrespective of land ownership. In January 2014, an Oregon 
stakeholder group was formed to work with the HMCG to extend 
conservation efforts for the coastal marten into Oregon. This informal 
group includes participation from Federal, State, timber, and tribal 
interests.
    The HMCG is cooperatively developing a conservation strategy to 
address coastal marten population and habitat needs across its range, 
including the goal of increasing the abundance and distribution of 
coastal martens through habitat retention, habitat restoration, and 
establishment of additional populations within their historical range. 
The strategy uses strategic habitat conservation and adaptive 
management principles, and will identify necessary permits and 
compliance needs well in advance of the need for such authorization. 
Each party seeks input and support from scientific and technical 
support staff within their agencies or organizations for the entire 
HMCG to consider for integration in overall planning, implementation, 
analysis, and monitoring efforts collectively found to be necessary for 
the conservation of coastal marten and its habitat. It is not the 
intent of the conservation strategy to supplant any ongoing and planned 
conservation efforts by the individual parties; instead, the 
conservation strategy intends to identify opportunities to enhance 
those conservation efforts. The HMCG holds quarterly meetings to 
facilitate completion and implementation of the conservation strategy. 
The California component of the conservation strategy is estimated to 
be completed in the spring of 2015, followed by the Oregon component in 
late 2015 or early 2016. A final conservation strategy for both states 
(as a single coastal marten conservation strategy) is estimated to be 
completed in 2016.
    Tribes that own or manage lands within the historical range of the 
coastal marten (and may or may not have currently suitable coastal 
marten habitat on their lands) include: Coquille Indian Tribe; 
Confederated Tribes of Grand Ronde Community of Oregon; Confederated 
Tribes of Siletz Indians of Oregon (Siletz Indians); Hoopa Valley 
Tribe, California; Yurok Tribe of the Yurok Reservation, California 
(Yurok Tribe); Wiyot Tribe, California; Karuk Tribe; Elk Valley 
Rancheria, California; Smith River Rancheria, California; Resighini 
Rancheria, California; Big Lagoon Rancheria, California; Cher-Ae 
Heights Indian Community of the Trinidad Rancheria, California; Blue 
Lake Rancheria, California; Bear River Band of the Rohnerville 
Rancheria, California; Cahto Tribe of the Laytonville Rancheria; 
Sherwood Valley Rancheria of Pomo Indians of California; and Manchester 
Band of Pomo Indians of the Manchester Rancheria, California.
    Although suitable habitat for coastal martens may occur on tribal 
lands, our records indicate that none of the tribes in coastal Oregon 
or in coastal northern California specifically manage for coastal 
marten populations or habitat on their lands. However, the Siletz 
Indians manage 1,700 ha (4,300 ac) of forest land for the benefit of 
marbled murrelets (Brachyramphus marmoratus) in Oregon, which 
coincidentally may also provide suitable habitat for coastal martens, 
and the Yurok Tribe is a member of the HMCG and currently owns 
approximately 23 percent of the total area of the coastal northern 
California population area, most of which is occupied by coastal 
martens. The best available information does not identify what the 
Yurok Tribe's vegetation management activities or potential impacts may 
be to coastal martens and their habitat. However, we will continue to 
work with the Yurok Tribe, including through the HMCG, and explore 
potential coastal marten conservation actions on their lands. We also 
anticipate coordinating with other tribes that may harbor suitable 
coastal marten habitat within the range of the coastal marten.
    In addition to conservation actions either planned or already being 
implemented related to the HMCG and tribal efforts, the Green Diamond 
Resource Company's (formerly Simpson Timber Company) 1992 Northern 
Spotted Owl Habitat Conservation Plan (HCP) (Simpson Timber Company 
1992, entire) covers lands that contain suitable habitat for coastal 
marten. This HCP describes how Green Diamond Resource Company 
identifies (during planning for timber harvest) ways to retain resource 
attributes that provide core habitat for future northern spotted owl 
habitat, including retention of: (1) Hardwood and conifer patches, (2) 
habitat structure along watercourses, (3) hard and soft snags, (4) 
standing live culls (i.e., trees of marketable size that are useless 
for all but firewood or pulpwood because of crookedness, rot, injuries, 
or damage from disease or insects), and (5) small areas of undisturbed 
brush (Simpson Timber Company 1992, entire). These HCP goals 
coincidentally will provide a

[[Page 18767]]

benefit to coastal martens that may occur on those lands. However, we 
note that the level and extent of resource retention are not defined, 
and the current description to retain ``small areas of undisturbed 
brush'' is helpful, but not necessarily adequate for the needs of the 
coastal marten (i.e., management relies primarily on clear cut 
management of timberlands). The Green Diamond Resource Company is in 
the initial stages of developing a new HCP for their lands, although 
currently the coastal marten is not a covered species. Because 11 
percent of the coastal northern California extant population area is on 
Green Diamond Resource Company timberlands, we are currently working 
with them to incorporate conservation actions into the HCP that would 
benefit the coastal marten and its habitat, particularly in those areas 
that lie between large suitable tracks of public lands.

Finding

    As required by the Act, we considered the five factors in assessing 
whether the coastal marten is an endangered or threatened species 
throughout all of its range. We examined the best scientific and 
commercial data available regarding the past, present, and future 
stressors faced by the coastal marten. We reviewed the petition, 
information available in our files, and other available published and 
unpublished information, and we consulted with recognized marten and 
habitat experts, and other Federal, State, and tribal agencies. Listing 
is warranted if, based on our review of the best available scientific 
and commercial data, we find that the stressors to the coastal DPS of 
the Pacific marten are so severe or broad in scope as to indicate that 
the coastal marten is in danger of extinction (endangered), or likely 
to become endangered within the foreseeable future (threatened), 
throughout all or a significant portion of its range.
    For the purposes of this evaluation, we are required to consider 
potential impacts to coastal martens into the foreseeable future. Based 
on the best available scientific and commercial information and to 
provide the necessary temporal context for assessing stressors to 
coastal martens, we determined 15 years (i.e., 3 marten generations) to 
be the foreseeable future for consideration of most of the stressors to 
coastal marten, as this period allows for analysis of multiple 
generations of coastal martens over a reasonable time period, as 
opposed to examining further into the future where assumptions or 
extensive uncertainty would not allow meaningful predictions of 
potential future impacts. For two stressors, we have defined different 
periods: 30 years constitutes the foreseeable future over which we 
assessed the stressor of wildfire (based on the expected future 
equivalent level of fire frequency, size, and severity as compared to 
the past 30 years), and 40-50 years constitutes the foreseeable future 
over which we assessed the stressor of climate change (based on model 
projections of climate changes for coastal Oregon and coastal northern 
California).
    We evaluated each of the potential stressors in the Species Report 
(Service 2015, entire) for the coastal DPS of Pacific marten, and we 
determined that wildfire (Factor A), habitat impacts due to the effects 
of climate change (Factor A), vegetation management (Factor A), 
development (Factor A), trapping (for fur and research purposes) 
(Factor B), disease (Factor C), predation (Factor C), collision with 
vehicles (Factor E), exposure to toxicants (Factor E), and small and 
isolated population size effects (Factor E) are factors that have 
either minimally impacted individuals in one or more of the populations 
or that may potentially have impacts on individuals or populations in 
the future. Our analysis resulted in the following conclusions for each 
of the stressors:
     Wildfire impacts are likely to occur throughout the range 
of the coastal marten similar to the historical impacts that have 
occurred based on the impact level estimates of the prevalence of 
wildfires within each extant population area between 1984-2012 (roughly 
30 years). Overall, these impacts do not rise to the level of a threat 
based on the continued persistence of moderate- and high-quality 
habitat following past fires, the continued presence of relatively 
moist habitat conditions (overall) that moderate the dry conditions 
that promote fire ignition and spread, and little effect of altered 
structure or composition of the dominant forest types in areas that 
have experienced fire suppression. Thus, we do not anticipate a 
significant reduction in suitable habitat for coastal martens as the 
result of wildfire.
     Climate change modeling predicts a range of potential 
effects on vegetation, including some that indicate conditions could 
remain suitable for coastal martens in portions of the coastal range. 
The severity of potential impacts to coastal marten habitat will likely 
vary across the range, with effects to coastal martens potentially 
ranging from negative to neutral or potentially beneficial. Although 
many climate models generally agree about the changes in temperature 
and precipitation, the consequent effects on vegetation are more 
uncertain, as is the rate at which any such changes might be realized. 
Therefore, it is not clear how or when changes in forest type and plant 
species composition will affect the distribution of coastal marten 
habitat. There is additional uncertainty as to fine-scale features of 
suitable marten habitat that may be affected by climate change, whether 
any changes will occur at a scale relevant to the taxon, and how these 
changes will be expressed in the coastal marten populations. Overall, 
we lack sufficient information to predict with any certainty the future 
direct impacts of climate change on coastal marten habitat or 
populations. Consequently, we have determined that we do not have 
reliable information to suggest that climate change is a threat to 
coastal marten habitat now or in the future, although we will continue 
to seek additional information concerning how climate change may affect 
coastal marten habitat.
     Vegetation management is likely to have an overall low 
impact on the loss, degradation, or fragmentation of suitable coastal 
marten habitat across the range of the DPS both currently and into the 
future. Some loss of suitable habitat (primarily low-quality suitable 
habitat) is expected to continue to occur into the future on private 
lands within all three population areas. However, private lands support 
a relatively small proportion of the suitable habitat available for 
coastal martens within extant population areas. Federal lands 
constitute a majority of the extant population areas, have longer 
timber-harvest rotations, and retain more structural features on the 
subset of that area in matrix lands. In addition, most of the Federal 
lands that provide suitable habitat are in Federal Reserves, which are 
managed for the maintenance and recruitment of late-successional 
habitat characteristics beneficial for coastal martens; suitable 
habitat is thus expected to increase in Federal Reserves. Therefore, 
overall potential impacts from vegetation management do not rise to the 
level of a threat.
     Development has an overall low impact on the loss, 
degradation, or fragmentation of suitable coastal marten habitat across 
the range of the DPS both currently and into the future, and thus does 
not rise to the level of a threat. If development does occur, loss of 
suitable habitat is expected to be minimal, as has been the trend over 
the past 30 years.
     Fur trapping of coastal martens has no impact to the 
population in coastal northern California because trapping for martens 
is illegal in California. Possible illegal fur trapping in California, 
as well as rangewide potential impacts

[[Page 18768]]

associated with livetrapping for research purposes or incidental 
trapping of martens (when intentionally trapping for other furbearer 
species) is not expected to result in population-level impacts. Some 
martens could be trapped in Oregon where fur trapping for martens is 
legal, although we estimate that potential impacts will not be 
significant at the population- or rangewide level based on the best 
available trapping data for Oregon. Additionally, potential impacts 
from live-trapping and handling for research purposes on coastal marten 
populations is discountable. Thus, impacts from fur trapping and 
trapping for research purposes across the coastal marten's range do not 
rise to the level of a threat.
     Disease has not been documented in the past within coastal 
marten populations. The prevalence of possible past exposure to lethal 
pathogens within the coastal northern California population and the 
coastal Oregon populations has not been determined, and we have no 
information to suggest that disease is currently present in any of the 
populations. At this point in time, there is a low probability that a 
disease outbreak may occur. We anticipate that if there should be an 
outbreak, it would likely have a low impact on all three coastal marten 
populations combined since the distance between the extant populations 
makes it unlikely that an outbreak would spread to all three 
populations. Thus, disease does not rise to the level of a threat.
     Predation is a natural process and is generally only 
considered a threat if it is occurring at unnaturally high levels that 
are not sustainable. The population-level impact of predation within 
the three coastal marten extant population areas is currently unknown, 
although the best available data from one evaluation of predation 
indicate a 33 percent annual predation rate for the coastal northern 
California population (Slauson et al. 2014, unpubl. data). This level 
of predation is expected to be sustainable when compared with the 
observed annual juvenile coastal marten survival rate of 50 percent, 
and thus predation alone would not likely result in a population-level 
impact. Therefore, based on the best available data at this time, we 
have determined that predation does not rise to the level of a threat 
given that it is a natural phenomenon that appears to be occurring at a 
sustainable level.
     Collisions with vehicles are rare, but they can be 
expected into the future. Known rates of mortality due to collisions 
with vehicles have been low for coastal martens, and the best available 
information does not suggest any significant increases in vehicular 
traffic or new highways to be built in areas where martens occur. 
Therefore, it is reasonable to expect the impact of collisions with 
vehicles on coastal martens to continue at similar levels into the 
future and not rise to the level of a threat.
     Illegal and legal marijuana cultivation sites (and use of 
ARs and other pesticides) are present within or near all three coastal 
marten populations, although the probability of exposure varies between 
them. The degree of exposure and the effect of such exposure on coastal 
martens, should it occur, is unknown and thus far unstudied. There is 
significant uncertainty as to the severity of impact that this stressor 
may have on coastal martens at the population- and rangewide levels 
given that the best available data are minimal regarding this stressor 
and coastal martens at this time, and given the lack of information 
regarding potential sublethal effects. Furthermore, it is unclear how 
the recent legalization of marijuana in Oregon will affect the amount 
or spread of illegal marijuana grow sites. The best available 
information does not suggest that these potential impacts rise to the 
level of a threat, primarily based on the available information on 
levels of known marten exposure to ARs and lack of evidence that ARs 
are having a population-level effect.
     Small, isolated populations are more susceptible to 
impacts, and therefore, we evaluated whether coastal marten populations 
are small and isolated such that these negative effects are likely to 
be realized. At this time, evidence suggests that coastal marten 
distribution has contracted markedly in California and southern Oregon 
since the early 20th century. Although the coastal northern California 
population abundance declined in the recent past (based on survey data 
between 2000 and 2008 (Slauson et al. 2009b, p. 10)), the population 
abundance since that time appears to have remained unchanged as 
indicated by the most recent preliminary abundance estimates available 
from 2012. The abundance and trend of coastal marten populations in 
coastal Oregon is unknown, although recent surveys in some areas of 
coastal Oregon (which are not yet complete) are documenting the 
presence of martens as anticipated. Although the known populations are 
disjunct, the dispersal capabilities of martens and habitat modeling 
suggest the potential for interchange of individuals between the 
populations. In addition, martens may occur between or adjacent to the 
known populations in areas where surveys have been limited or absent. 
The best available data at this time indicate that although coastal 
martens are likely reduced in abundance or distribution relative to 
their historical numbers and range, there is no empirical evidence that 
any current populations of coastal marten are in decline. Thus, small 
or isolated population size effects do not rise to the level of a 
threat either currently or in the foreseeable future.
     Potential cumulative impacts to the coastal marten from 
all stressors combined or some of the stressors are possible; however, 
the most likely scenarios for cumulative impacts are likely to only 
occur from the following three scenarios: Increased frequency or size 
of wildfires associated with potential climate changes; increased 
coastal marten mortality rates from predation, disease, or other 
factors following a sublethal exposure to toxicants; or possible 
increased coastal marten predation rates due to decreased shrub 
densities resulting from vegetation management activities. Based on the 
best available data at this time and as described above, none of these 
possible cumulative impacts are likely to occur currently or into the 
foreseeable future to such a degree that the effects are expected to 
lead to population- or rangewide-level declines. Therefore, the 
cumulative impact of these potential stressors does not rise to the 
level of a threat.
    We also evaluated existing regulatory mechanisms (Factor D) and did 
not determine an inadequacy of existing regulatory mechanisms for 
coastal marten. Specifically, we found that multiple Federal land use 
plans (e.g., LRMPs, NWFP) or State regulations (e.g., Oregon forest 
practice rules) are being implemented, often providing broad latitude 
for land managers, but with explicit sideboards for directing 
management activities. We also note that significant Federal efforts 
have been developed and are being implemented (e.g., NWFP) to abate the 
large-scale loss of forested habitat-types deemed essential for coastal 
martens. Additional efforts are also underway within the reserve areas 
that constitute a majority of the Federal lands in areas occupied by 
coastal martens to promote further recruitment of such habitat.
    None of these impacts, as summarized above, was found to 
individually or cumulatively impact the coastal DPS of Pacific marten 
to a degree such that listing is warranted at this time. Based on the 
analysis contained within the Species Report (Service 2015, pp. 41-95), 
we conclude that the best available scientific and commercial 
information indicates that these stressors are not

[[Page 18769]]

singly or cumulatively causing a decline of the DPS or its habitat 
currently, nor are the stressors likely to be significant in the 
foreseeable future to the degree that they would result in declines of 
one or more populations such that the DPS would be in danger of 
extinction, or likely to become so within the foreseeable future.
    We base our decision on the following:
    (1) Although habitat-based impacts may be occurring currently or in 
the future primarily as a result of wildfire and vegetation management 
(and, to an unknown degree, the effects of climate change), much of the 
coastal marten's habitat is not in especially fire-prone forest types, 
and vegetation management has significant impacts only on the 
relatively small area in private ownership within its range. 
Significant amounts of moderate- and high-suitability habitat are 
currently available on Federal and State lands within all three 
population areas, including approximately 44 percent of the coastal 
central Oregon population area, 70 percent of the coastal southern 
Oregon population area, and 63 percent of the coastal northern 
California population. Moderate- and high-suitability habitat in the 
coastal central Oregon population area is a currently undetermined 
value greater than 44 percent because the habitat suitability model did 
not account for occupied coastal dune habitat that exists as a narrow 
coastal strip along the western boundary of that population area. 
Overall, the existing moderate- and high-suitability habitat includes 
some areas that appear to be either (or both): (a) Resilient to many 
high-severity fires due to pronounced levels of precipitation and cool, 
moist summer conditions that exist along the coast currently and into 
the future; and (b) protected from significantly damaging treatments of 
vegetation management (i.e., State and Federal lands such as those 
being managed under the NWFP, National Park Service lands, and lands 
managed by the Oregon and California Department of Parks and 
Recreation), including 77 percent of the moderate- and high-suitability 
habitat in the coastal central Oregon population area, 90 percent of 
the moderate- and high-suitability habitat in the coastal southern 
Oregon population area, and 78 percent of the moderate- and high-
suitability habitat in the coastal northern California population area.
    (2) Coastal marten populations throughout their range have likely 
experienced declines or significant impacts in the past (i.e., 
harvesting and trapping for fur), which undoubtedly influenced the 
current distribution of these populations. The population size of 
coastal martens in the coastal northern California population area is 
estimated to be fewer than 100, but is no longer in decline as shown by 
survey data available from 2000, 2008, and preliminary abundance 
estimates from 2012. The abundance and distribution of coastal martens 
in coastal Oregon is unknown, coastal northern Oregon is unsurveyed, 
and there are no data available on which to estimate any trend in known 
populations in coastal central and coastal southern Oregon. We presume 
that coastal marten populations may not be especially large or 
expansive, given the historical impacts of overtrapping and timber 
harvest. However, these past threats have been largely ameliorated, and 
we have no evidence to suggest that current stressors are resulting in 
any population declines, such that we would consider the DPS of coastal 
marten to be on a trajectory toward extinction. We thoroughly evaluated 
impacts to the DPS and its habitat with regard to the five listing 
factors. Similar to the stressors described in (1) above for potential 
impacts to habitat, we found minimal evidence of population-level 
impacts.
    We recognize a need to continue to monitor the coastal marten 
because the populations are disjunct, which in general makes them more 
susceptible to stressors than species with larger, more well-connected 
populations. There has been relatively little survey effort throughout 
much of the range of the DPS, however. In general, the interchange of 
only a few individuals is needed to maintain genetic connectivity 
between populations over time. As described in this document and the 
Species Report (Service 2015, entire), there are stressors that we find 
may be having some effect on coastal marten populations, albeit not to 
the degree that they currently rise to the level that listing is 
warranted. We will continue to monitor the status of the DPS and 
evaluate any other information we receive. Additional information will 
continue to be accepted on all aspects of the DPS. If at any time data 
indicate that protective status under the Act should be provided or if 
there are new threats or increasing stressors that rise to the level of 
a threat, we can initiate listing procedures, including, if 
appropriate, emergency listing pursuant to section 4(b)(7) of the Act.
    In conclusion, we acknowledge that the coastal marten population in 
California may be reduced in size relative to its historical abundance, 
and that coastal martens may be reduced in distribution as compared to 
their historical range. A listing determination, however, must be based 
on our assessment of the current status of the species--in this case, 
the coastal DPS of the Pacific marten--in relation to the five listing 
factors under the Act. Section 4 of the Act requires that we make such 
a determination based solely on the best scientific and commercial data 
available. To this end, we must rely on reasonable conclusions as 
supported by the best available science to assess the current and 
future status to determine whether the coastal marten meets the 
definition of an endangered or threatened species under the Act. Based 
on our review of the best available scientific and commercial 
information pertaining to the five factors, we find that the stressors 
acting upon the coastal DPS of the Pacific marten are not of sufficient 
imminence, intensity, or magnitude to indicate that the coastal marten 
is in danger of extinction now (endangered), or likely to become 
endangered within the foreseeable future (threatened), throughout all 
of its range.

Significant Portion of the Range

    Under the Act and our implementing regulations, a species may 
warrant listing if it is an endangered or a threatened species 
throughout all or a significant portion of its range. The Act defines 
``endangered species'' as any species which is ``in danger of 
extinction throughout all or a significant portion of its range,'' and 
``threatened species'' as any species which is ``likely to become an 
endangered species within the foreseeable future throughout all or a 
significant portion of its range.'' The term ``species'' includes ``any 
subspecies of fish or wildlife or plants, and any distinct population 
segment [DPS] of any species of vertebrate fish or wildlife which 
interbreeds when mature.'' We published a final policy interpreting the 
phrase ``Significant Portion of its Range'' (SPR) (79 FR 37578; July 1, 
2014). The final policy states that (1) if a species is found to be an 
endangered or a threatened species throughout a significant portion of 
its range, the entire species is listed as an endangered or a 
threatened species, respectively, and the Act's protections apply to 
all individuals of the species wherever found; (2) a portion of the 
range of a species is ``significant'' if the species is not currently 
an endangered or a threatened species throughout all of its range, but 
the portion's contribution to the viability of the species is so 
important that, without the members in that portion, the species would 
be in danger of extinction, or likely to become so in the foreseeable 
future, throughout

[[Page 18770]]

all of its range; (3) the range of a species is considered to be the 
general geographical area within which that species can be found at the 
time the Service or NMFS makes any particular status determination; and 
(4) if a vertebrate species is an endangered or a threatened species 
throughout an SPR, and the population in that significant portion is a 
valid DPS, we will list the DPS rather than the entire taxonomic 
species or subspecies.
    The SPR Policy is applied to all status determinations, including 
analyses for the purposes of making listing, delisting, and 
reclassification determinations. The procedure for analyzing whether 
any portion is an SPR is similar, regardless of the type of status 
determination we are making. The first step in our analysis of the 
status of a species (``species'' under the Act refers to any listable 
entity, including species, subspecies, or DPS) is to determine its 
status throughout all of its range. If we determine that the species is 
in danger of extinction, or likely to become so in the foreseeable 
future, throughout all of its range, we list the species as an 
endangered (or threatened) species and no SPR analysis is required. If 
the species is neither an endangered nor a threatened species 
throughout all of its range, we determine whether the species is an 
endangered or a threatened species throughout a significant portion of 
its range. If it is, we list the species as an endangered or a 
threatened species, respectively; if it is not, we conclude that 
listing the species is not warranted.
    When we conduct an SPR analysis, we first identify any portions of 
the species' range that warrant further consideration. The range of a 
species can theoretically be divided into portions in an infinite 
number of ways. However, there is no purpose to analyzing portions of 
the range that are not reasonably likely to be significant and either 
endangered or threatened. To identify only those portions that warrant 
further consideration, we determine whether there is substantial 
information indicating that (1) the portions may be significant, and 
(2) the species may be in danger of extinction in those portions or 
likely to become so within the foreseeable future. We emphasize that 
answering these questions in the affirmative is not a determination 
that the species is an endangered or a threatened species throughout a 
significant portion of its range--rather, it is a step in determining 
whether a more detailed analysis of the issue is required. In practice, 
a key part of this analysis is whether the threats are geographically 
concentrated in some way. If the threats to the species are affecting 
it uniformly throughout its range, no portion is likely to warrant 
further consideration. Moreover, if any concentration of threats apply 
only to portions of the range that clearly do not meet the biologically 
based definition of ``significant'' (i.e., the loss of that portion 
clearly would not be expected to increase the vulnerability to 
extinction of the entire species), those portions will not warrant 
further consideration.
    If we identify any portions that may be both (1) significant and 
(2) endangered or threatened, we engage in a more detailed analysis to 
determine whether these standards are indeed met. The identification of 
an SPR does not create a presumption, prejudgment, or other 
determination as to whether the species in that identified SPR is an 
endangered or a threatened species. We must go through a separate 
analysis to determine whether the species is an endangered or a 
threatened species in the SPR. To determine whether a species is an 
endangered or a threatened species throughout an SPR, we will use the 
same standards and methodology that we use to determine if a species is 
an endangered or a threatened species throughout its range.
    Depending on the biology of the species, its range, and the threats 
it faces, it may be more efficient to address the ``significant'' 
question first, or the status question first. Thus, if we determine 
that a portion of the range is not ``significant,'' we do not need to 
determine whether the species is an endangered or a threatened species 
there; if we determine that the species is not an endangered or a 
threatened species in a portion of its range, we do not need to 
determine if that portion is ``significant.''
    We consider the historical range of the coastal marten to include 
coastal Oregon from the Columbia River (Clatsop and Columbia counties) 
south into northern Sonoma County, California, including suitable 
habitat from the coast eastward to an elevation of 1,524 m (5,000 ft). 
This range encompasses the coastal central Oregon extant population 
area, the coastal southern Oregon extant population area, the coastal 
northern California extant population area, and the intervening 
habitat. Based on the best available information at this time, these 
populations account for the current distribution of the DPS.
    In considering any significant portion of the coastal marten's 
range, we considered whether the stressors facing the coastal marten 
might be different at three locations where the coastal martens have 
been found and, thus, geographically concentrated in some portion of 
the range of the DPS. In the Summary of Information Pertaining to the 
Five Factors analysis above, we identified the most likely potential 
differences associated with fur trapping in Oregon, wildfire, climate 
change, development and vegetation management (timber harvesting), and 
toxicant exposure.
    (1) Fur trapping is legal in Oregon, and thus the two Oregon 
populations may be affected by this activity. Population-level impacts 
of legal coastal marten fur trapping within the two Oregon extant 
population areas have not been studied, as the impact of trapping on a 
marten population requires an estimate of population abundance, which 
is currently unavailable for both extant population areas in coastal 
Oregon. Based on the very few individuals removed from this population 
over time (36 individuals harvested from trapping over a 26-year 
period, between 1969 and 1995--on average fewer than 2 per year), the 
best available data indicate that fur trapping is unlikely to result in 
population-level impacts.
    Fur trapping of martens is illegal in California but legal for 
other furbearer species. We expect that nearly all coastal martens that 
are accidentally captured in box traps set for other furbearer species 
(or that are live-trapped for research purposes) are released unharmed. 
Although illegal fur trapping specifically for martens is also a 
possibility in California, the best available data at this time do not 
indicate that illegal fur trapping or incidental legal live-trapping 
for coastal martens for research purposes is resulting in population-
level impacts. Overall, we do not find that the potential impacts from 
fur trapping (illegal or legal) and live-trapping for research purposes 
are geographically concentrated in any one portion of the range of the 
DPS.
    (2) The potential impacts from wildfire are slightly greater within 
the coastal southern Oregon and coastal northern California populations 
as compared to the coastal central Oregon population when considering 
historical (between 1984 and 2012) wildfire incidents and the 
likelihood that into the foreseeable future (approximately 30 years), 
the frequency, intensity, and severity of wildfires are expected to be 
similar to the recent past. However, these wildfires in coastal 
southern Oregon and coastal northern California have burned at varying 
levels of severity and have thus only partially impacted (i.e., not 
completely removed) suitable habitat and the adjacent, intervening

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suitable habitat that the coastal marten would need to rely on during 
post-fire habitat recovery periods. Surveys of these areas (including 
the drier, inland, xeric areas) post-burn indicate that low-, moderate-
, and high-suitability habitat remain within and adjacent to these past 
wildfire perimeters. Therefore, although future wildfires are expected 
to occur similarly to those documented in the past 30 years throughout 
the coastal marten's range (i.e., among all three extant population 
areas), and given the potential for increased temperatures and 
decreased precipitation over the next 50 years (see ``Climate Change'' 
under Factor A, above) throughout its entire range, we do not 
anticipate a concentration of threats in any one portion of the DPS' 
range due to:
    (a) The coastal marten's range continuing to occur within a 
(generally) fog-influenced coastal zone, and thus the continued 
widespread presence of persistent, moist conditions year-round 
(including Pacific storms in the winter and cloud cover or coastal fog 
in the summer) that likely result in lower severity wildfires than what 
would occur in areas without the a moist, coastal influence; and
    (b) The anticipated widespread presence of varying levels of 
suitable habitat post-fire throughout the coastal marten's range, as 
demonstrated by post-burn surveys.
    (3) The potential impacts from climate change are slightly greater 
within the coastal southern Oregon and coastal northern California 
populations, which models indicate could result in a warmer and drier 
climate into the foreseeable future (40 to 50 years) as compared to the 
coastal central Oregon population. Nearly all models that encompass the 
landscape containing these two population areas show shifts in 
vegetation type to habitat that may be considered less favorable for 
coastal martens. However, most models project these shifts in 
vegetation type over time by the end of the century, and the models 
predict these same potential vegetation shifts in coastal central and 
northern Oregon. Additionally, even if vegetation shifts occur, 
suitable habitat for coastal martens is expected to remain in portions 
of the coastal southern Oregon and coastal northern California 
population areas, to which coastal martens could migrate (see Climate 
Change, above). Overall, we do not anticipate a geographic 
concentration of threats in any one portion of the DPS' range given the 
variety of potential effects from climate change, the high level of 
uncertainty regarding the nature and timing of any such effects, and 
the likelihood that suitable habitat for coastal martens will remain 
available into the foreseeable future throughout the entire range of 
the DPS despite potential climate change impacts.
    (4) Both development (e.g., road building, dam construction and 
creation of new reservoirs, conversion of forest habitat for 
agricultural use, development and expansion of recreational areas) and 
vegetation management (e.g., timber harvest, thinning, fuels reduction) 
are expected to continue on some private lands throughout the range of 
the coastal marten. These activities potentially may occur to a greater 
extent in the coastal central Oregon population area as compared to the 
coastal southern Oregon and coastal northern California population 
areas due to the greater percentage of moderate- and high-suitability 
marten habitat in private ownership in the coastal central Oregon 
population area (i.e., 23 percent as opposed to 10 percent and 11 
percent, respectively). However, the best available data do not 
indicate that either potential development activities or vegetation 
management in one or more of these population areas will occur at a 
level greater than any other (i.e., the potential impacts are uniformly 
distributed throughout the DPS's range). Additionally, the best 
available data do not indicate that any new development or vegetation 
management activities (i.e., those that would remove currently suitable 
habitat) would occur into the foreseeable future to such a degree that 
population-level impacts are likely. We have made this conclusion 
primarily based on the extensive amount of Federal lands both within 
and adjacent to all three populations where overall beneficial 
vegetation management (such as that outlined in the NWFP) would occur, 
thus providing an overall conservation benefit to coastal marten 
rangewide.
    Some vegetation management activities may also occur throughout the 
coastal marten's range that may result in short-term impacts to coastal 
marten (such as thinning, fuels reduction projects, and habitat 
restoration), but eventually result in long-term benefits to coastal 
martens and their habitat. In these cases, the long-term benefits 
likely outweigh the potential short-term, localized impacts by 
improving habitat suitability for the coastal marten in the long-term 
through: (a) Minimizing loss of late-successional stands due to 
wildfires, and (b) accelerating the development of late-seral 
characteristics. Although short-term degradation of suitable habitat 
could occur, these types of projects are designed to ultimately 
increase the overall amount, distribution, and patch size of suitable 
coastal marten habitat.
    (5) Potential exposure of coastal martens to toxicants as a result 
of illegal marijuana cultivation sites is likely to continue on some 
lands within the coastal marten's range. This type of activity could 
potentially occur in those areas where marijuana grow sites are located 
(which currently is known to be a fraction of the coastal marten's 
range). Based on the presence of suitable climate conditions for 
marijuana cultivation and data that indicate a greater concentration of 
recently eradicated cultivation sites within or near the coastal 
northern California population area, these activities may possibly 
occur to a greater extent in the coastal northern California population 
area as compared to the coastal Oregon population areas. Of note is 
that incidence of toxicant exposure and the potential population-level 
effects to coastal marten are largely unknown, and there is significant 
uncertainty as to the severity of impact (both lethal and sublethal) 
that this stressor may have at the population- and rangewide levels on 
coastal marten, especially given the recent legalization of marijuana 
in Oregon (note that marijuana is not legal in California). The best 
available data indicate broad use of ARs at illegal marijuana 
cultivation sites, as well as continued use of ARs at legal grow sites, 
both of which are found within the range of the DPS, but the degree of 
exposure that may result for coastal martens is unknown. To date, only 
one record of a positive exposure exists within the range of the 
coastal marten that demonstrates exposure to ARs. Therefore, at this 
time, the best available data do not indicate that the coastal marten's 
exposure to ARs will occur at a level greater than any other in any one 
portion of the range of the DPS.
    In summary, our evaluation of the best available information 
indicates that the overall level of stressors is not geographically 
concentrated in one portion of the coastal marten's range, and that the 
stressors that have the potential to impact coastal martens are 
relatively consistent across its range (Service 2015, entire). 
Therefore, it is our conclusion, based on our evaluation of the current 
potential threats to the coastal marten (see Summary of Information 
Pertaining to the Five Factors section of this finding and the 
``Stressors on Coastal Marten Populations and Habitat'' section of the 
Species Report (Service 2015, pp. 41-95)), that no portion of the range 
of the coastal DPS of Pacific marten warrants

[[Page 18772]]

further consideration of possible endangered or threatened status under 
the Act.
    Our review of the best available scientific and commercial 
information indicates that the coastal marten is not in danger of 
extinction (endangered) nor likely to become endangered within the 
foreseeable future (threatened), throughout all or a significant 
portion of its range. Therefore, we find that listing the coastal DPS 
of the Pacific marten as an endangered or threatened species under the 
Act is not warranted at this time.
    We request that you submit any new information concerning the 
status of, or threats to, the coastal marten to our Arcata Fish and 
Wildlife Office (see ADDRESSES) whenever it becomes available. New 
information will help us monitor coastal martens and encourage their 
conservation. If an emergency situation develops for the coastal 
marten, we will act to provide immediate protection.

References Cited

    A complete list of references cited is available on the Internet at 
http://www.regulations.gov and upon request from the Arcata Fish and 
Wildlife Office (see ADDRESSES).

Authors

    The primary authors of this document are the staff members of the 
Pacific Southwest Regional Office.

Authority

    The authority for this section is section 4 of the Endangered 
Species Act of 1973, as amended (16 U.S.C. 1531 et seq.).

    Dated: March 30, 2015.
Robert Dreher,
Acting Director, U.S. Fish and Wildlife Service.
[FR Doc. 2015-07766 Filed 4-6-15; 8:45 am]
 BILLING CODE 4310-55-P