[Federal Register Volume 73, Number 16 (Thursday, January 24, 2008)]
[Proposed Rules]
[Pages 4380-4418]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E8-918]



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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 the Siskiyou Mountains Salamander (Plethodon stormi) 
and Scott Bar Salamander (Plethodon asupak) as Threatened or 
Endangered; Proposed Rule

  Federal Register / Vol. 73, No. 16 / Thursday, January 24, 2008 / 
Proposed Rules  

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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[FWS-R8-ES-2008-0002; 1111 FY07 MO;ABC Code: B2]


Endangered and Threatened Wildlife and Plants; 12-Month Finding 
on a Petition To List the Siskiyou Mountains Salamander (Plethodon 
stormi) and Scott Bar Salamander (Plethodon asupak) as Threatened or 
Endangered

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 Siskiyou Mountains 
salamander (Plethodon stormi) and Scott Bar salamander (Plethodon 
asupak) as threatened or endangered, under the Endangered Species Act 
of 1973, as amended (Act). After a thorough review of all available 
scientific and commercial information, we find that listing the 
Siskiyou Mountains salamander and Scott Bar salamander is not 
warranted. We ask the public to continue to submit to us any new 
information concerning the status of, and threats to, these species. 
This information will help us to monitor and encourage the ongoing 
management of these species.

DATES: We made the finding announced in this document on January 24, 
2008.

ADDRESSES: This finding is available on the Internet at http://www.regulations.gov and http://www.fws.gov/yreka/. 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, Yreka Fish and Wildlife Office, 1829 S. 
Oregon Street, Yreka, CA 96097; telephone 530-842-5763; facsimile 530-
842-4517. Please submit any new information, materials, comments, or 
questions concerning this finding to the above address or via 
electronic mail (e-mail) at [email protected].

FOR FURTHER INFORMATION CONTACT: Phil Detrich, Field Supervisor, U.S. 
Fish and Wildlife Service, Yreka Fish and Wildlife Office (see 
ADDRESSES section). If you use a telecommunications device for the deaf 
(TDD), call the Federal Information Relay Service (FIRS) at 800-877-
8339.

SUPPLEMENTARY INFORMATION: 

Background

    Section 4(b)(3)(B) of the Act (16 U.S.C. 1531 et seq.) requires 
that, for any petition to revise the Lists of Endangered and Threatened 
Wildlife and Plants that contains substantial scientific and commercial 
information that listing may be warranted, we make a finding within 12 
months of the date of our receipt of the petition on whether the 
petitioned action is: (a) Not warranted, (b) warranted, or (c) 
warranted, but the immediate proposal of a regulation implementing the 
petitioned action is precluded by other pending proposals to determine 
whether any species is threatened or endangered. Such 12-month findings 
are to be published promptly in the Federal Register. 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, and we must make a subsequent 
finding within 12 months.

Previous Federal Actions

    On June 18, 2004, we received a petition dated June 16, 2004, from 
the Center for Biological Diversity, Klamath-Siskiyou Wildlands Center, 
and Noah Greenwald, to list the Siskiyou Mountains salamander 
(Plethodon stormi) as a threatened or endangered species on behalf of 
themselves and five other organizations. The petition clearly 
identified itself as such and included the requisite identification 
information for the petitioners, as required in 50 CFR 424.14(a). In 
their petition, the petitioners assert that there are three separate 
distinct population segments (DPSs) of the Siskiyou Mountains 
salamander, one of which consists of the Scott Bar salamander. 
Alternatively, the petitioners assert that the Scott Bar salamander is 
a separate species and request that it be considered independently for 
listing. Since the time the petition was submitted, the Scott Bar 
salamander (Plethodon asupak) has been recognized as a species separate 
from the Siskiyou Mountains salamander (Mead et al. 2005, pp. 169-171), 
and we have reviewed it separately in making this finding. The 
petitioners also requested the Service to consider whether the Siskiyou 
Mountains salamander (and therefore the Scott Bar salamander, as well) 
warrants listing throughout a significant portion of its range, and 
requested designation of critical habitat for both species concurrent 
with their listing. In a July 19, 2004, letter to the petitioners, we 
responded that we reviewed the petition for both species and determined 
that an emergency listing was not warranted, and that because of 
inadequate funds for listing and critical habitat designation, we would 
not be able to otherwise address the petition to list the Siskiyou 
Mountains salamander and Scott Bar salamander at that time.
    On June 23, 2005, we received a 60-day notice of intent to sue and 
on August 23, 2005, the Center for Biological Diversity and four other 
groups filed a Complaint for Declaratory and Injunctive Relief in 
Federal District Court for the District of Oregon (Center for 
Biological Diversity et al. v. Norton et al., No. 3:05-CV-1311-BR), 
challenging our failure to issue a 90-day finding on the petition to 
list the Siskiyou Mountains salamander and Scott Bar salamander. On 
December 28, 2005, we reached an agreement with the plaintiffs to 
complete the 90-day finding by April 15, 2006, and if we determined 
that the petition presented substantial information that listing may be 
warranted, to complete the 12-month finding by January 15, 2007.
    On April 17, 2006, the Service made its 90-day finding (71 FR 
23886, April 25, 2006), concluding that the petition did not present 
substantial scientific or commercial information to indicate that 
listing the Siskiyou Mountains salamander and Scott Bar salamander may 
be warranted.
    On July 6, 2006, the Center for Biological Diversity and others 
filed suit in the United States District Court for the Northern 
District of California (Center for Biological Diversity et al. v. Dirk 
Kempthorne et al., No. C-06-4186-WHA), challenging the merits of that 
finding. On January 19, 2007, the District Court determined the 90-day 
finding was arbitrary and capricious, vacated and remanded the finding, 
and ordered the Service to make a new finding by March 23, 2007.
    A new 90-day finding was signed on March 22, 2007, and we published 
it in the Federal Register on March 29, 2007 (72 FR 14750). In that 90-
day finding, we concluded that the petition presented substantial 
scientific or commercial information to indicate that listing the 
Siskiyou Mountains salamander and Scott Bar salamander may be 
warranted, announced the initiation of a status review of these taxa, 
and solicited comments and information to be provided in connection 
with the status review by May 29, 2007. This notice constitutes our 12-
month finding regarding the petition to list these two species.
    To ensure that this finding is based on the latest information and 
incorporates the opinions of the scientific community, the Service 
entered into a

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Cooperative Agreement with the U.S. Geological Survey, Forest and 
Rangeland Ecosystem Science Center, in Corvallis, Oregon, to provide a 
technical report addressing taxonomy, biology, habitat associations, 
detectability, and effects of habitat alteration on the salamanders. 
The technical report was authored by Douglas DeGross and R. Bruce Bury, 
and reviewed by species experts in the U.S. Geological Survey, Forest 
and Rangeland Ecosystem Science Center; U.S. Forest Service (USFS) 
Pacific Northwest Research Station and Pacific Southwest Research 
Station; and Rogue River-Siskiyou National Forest. The technical report 
(DeGross and Bury 2007), information provided by the public, and 
additional information and data in our files provided the basis for 
this status review for the Siskiyou Mountains salamander and Scott Bar 
salamander. In addition, Service staff involved in the development of 
this finding have several years of combined experience surveying for 
and researching the distribution and habitat associations of Siskiyou 
Mountains salamander.

Foreseeable Future

    The principal difference between an ``endangered'' and a 
``threatened'' species under the Act is whether the species is 
currently in danger of extinction, or if it is likely to become so 
``within the foreseeable future.'' The Act does not define the term 
foreseeable future; however, we consider the foreseeable future to be 
affected by the biological and demographic characteristics of the 
species, as well as our ability to predict or extrapolate the effects 
of threats facing the species in the future. Quantification of the time 
period corresponding to the forseeable future is challenging because it 
necessitates making predictions about inherently dynamic political, 
legal, and social mechanisms that influence the degree and immediacy of 
potential threats to the species.
    Population dynamics of the Siskiyou Mountains salamander and Scott 
Bar salamander are poorly known, and we are unaware of data sufficient 
to support estimates of longevity, generation times, or recruitment 
rates for these species. For example, Nussbaum et al. (1983, p. 103) 
state that both sexes ``are thought to'' mature at 5 to 6 years of age, 
but provide no basis for this estimate. Likewise, estimates of 
population and genetically effective population (Ne) size 
are unavailable for these species (DeGross and Bury 2007, p. 9). 
Because the demographic and biological characteristics of these species 
are so poorly understood, we must base our estimate of foreseeable 
future on our ability to predict or extrapolate the effects of the 
future threats facing these species.
    Our ability to predict the effects of future threats is limited to 
our knowledge of the time frame of the threats potentially facing the 
species (e.g., timber harvest, wildfire, roads and road construction, 
mining and rock quarrying, disease, stochastic events, and climate 
change) and of any conservation activities taking place to address 
these threats. For example, the rate of timber harvest has declined on 
Federal lands (which constitute over 85 percent of the combined ranges 
of both species) during the last 30 years (USDA and USDI 1994, 2005) 
and we have no information that would lead us to predict a dramatic 
increase in the rate and intensity of timber harvest such that large 
areas of habitat will be affected to such a great degree that these 
species will suffer adverse impacts. In the event that the rate and 
intensity of timber harvesting were to increase dramatically, it would 
take some period of time (depending on the actual increase of the rate 
and intensity, and the impact of the harvesting at issue on the 
salamanders) for the cumulative impact of the timber harvesting to have 
a significant effect on the species. Because the available evidence 
suggests that the salamanders recover for even intensive disturbances 
such as clearcutting (from 11 years (Bull et al. 2006, p. 21) to 30 
years (Welsh et al. 2007b) for Siskiyou Mountains salamanders), the 
species would only become in danger of extinction if that increased 
level and intensity of harvest lasted long enough to effect sufficient 
habitat at nearly the same time such that it overcame the apparent 
resiliency of the species to such disturbances. Further, while 
scientists predict that the rate of temperature change will continue to 
increase throughout the present century (EPRI 2003, p. 3; Hayhoe et al. 
2004, p. 12423; Cayan et al. 2006, pp. 11-14, 31; Maurer 2007, p. 317), 
the effects of climate change on these species are uncertain and 
estimation of the timing of potential effects would be speculative.
    We do not have sufficient demographic information on Siskiyou 
Mountains salamanders or Scott Bar salamanders, nor on the trajectory 
of potential threats when combined with existing regulatory mechanisms, 
on which to base a precise definition of foreseeable future. Given the 
stability of Federal Land and Resource Management Plans and the 
Northwest Forest Plan (NWFP) since its establishment in 1994, we assume 
that significant changes to current land management practices on 
Federal lands are not likely to occur within 20 years. We note that the 
changes in Federal land management that we can anticipate may happen in 
the short term, including termination of the Survey and Manage Program 
and Western Oregon Plan Revision, discussed below, are unlikely to 
result in the sort of significant changes that might have an important 
effect on the conservation status of the species. If a significant 
change were to occur, we estimate that, because of logistical and 
regulatory limitations imposed on the rate of planning and implementing 
significant land management actions, actual management activities could 
take an additional 20 years to reach a magnitude of effect that would 
measurably affect salamander populations. Therefore, we conclude that 
the foreseeable future for the salamanders does not extend beyond 40 
years. In other words, we have sufficient confidence in our estimates 
of the threats and reaction of the two species to those threats to draw 
a conclusion as to the likelihood of endangerment over only at most 40 
years. Beyond that period, our level of confidence is such that any 
conclusions we drew would be too speculative on which to base current 
action. We find that this estimate of the foreseeable future is both 
reasonable and appropriate because it focuses this status review on the 
time frame in which current social and political change may affect 
species management, which we consider to have the most likely potential 
for meaningful near-term influence on the status of these species.

Species Descriptions

    Like others in the Family Plethodontidae (the lungless 
salamanders), the Siskiyou Mountains salamander and Scott Bar 
salamander are completely terrestrial, medium-sized, slender-bodied 
salamanders with short limbs and a dorsal stripe. Both species are 
found in or near talus (loose surface rock) and fissured rock outcrops 
where moisture and humidity are high enough to allow respiration 
through their skin (Feder 1983, p. 296; Nussbaum et al. 1983, pp. 73, 
90, and 102; Stebbins 2003, p. 168). Both species are endemic to the 
Klamath-Siskiyou Mountains of southern Oregon and northern California, 
where they are considered as part of a species complex that includes 
and is named for the similar Del Norte salamander (Plethodon 
elongatus).
    Members of the Plethodon elongatus Complex differ physically from 
other regional members of the genus

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Plethodon. Species in the Plethodon elongatus Complex have webbed toes, 
while Dunn's salamander (P. dunni) and western red-backed salamander 
(P. vehiculum) do not (Highton 1962, pp. 255-256). The larger number of 
trunk vertebrae and costal grooves (vertical creases along the side of 
the body), as well as the smaller number of vomerine teeth (teeth on 
the vomer bone in the roof of the mouth) further distinguish the 
Plethodon elongatus Complex from the rest of the western Plethodon 
species (Highton and Brame 1965, p. 1; Brodie 1970, pp. 503-505; 
Nussbaum et al. 1983, p. 102; Mead et al. 2005, pp. 163-166).
    The Siskiyou Mountains salamander was described in 1965, two years 
after it was first identified (Highton and Brame 1965, p. 1). It is 
characterized by a modal number of 17 costal grooves and 4 to 5.5 
intercostal folds (folds of skin between the costal grooves) between 
the toes of adpressed limbs (limbs firmly pressed against the sides of 
the body) (Nussbaum et al. 1983, p. 102; Leonard et al. 1993, p. 78). 
Adults have a light- to purplish-brown dorsum, and the body is 
sprinkled with a moderate to dense array of white to yellow flecks, 
concentrated on the sides and limbs and away from the light-brown 
dorsal stripe (Highton and Brame 1965, p. 1; Nussbaum et al. 1983, p. 
102). Juveniles are black and have an olive-tan dorsal stripe that 
extends onto the tail.
    The Scott Bar salamander is more robust and has a wider head and 
longer limbs than the Del Norte salamander and Siskiyou Mountains 
salamander. It has fewer intercostal folds between adpressed limbs (2.5 
to 3.5) than either the Del Norte salamander (5 to 6) or Siskiyou 
Mountains salamander (4 to 5.5), and the modal number of costal grooves 
(17) is one less than in the Del Norte salamander (18). The Scott Bar 
salamander has a longer body relative to its tail length and longer 
forelimbs and hindlimbs than the Siskiyou Mountains salamander or Del 
Norte salamander. The coloration of the Scott Bar salamander is similar 
to that of the Siskiyou Mountains salamander and is described in Mead 
et al. (2005, p. 170). Despite the morphological differences described 
in Mead et al. (2005, pp. 169-171), the two species are difficult to 
distinguish in the field.

Taxonomy

    The Siskiyou Mountains salamander was first identified in 1963, 
adding the second form to what is now referred to as the Plethodon 
elongatus Complex (Highton and Brame 1965, p. 1). Early distinctions 
between Siskiyou Mountains salamanders and Del Norte salamanders were 
based on morphological traits and coloration (Highton and Brame 1965, 
p. 1; Brodie 1970, pp. 503-505; Bury 1973, p. 57). However, it is now 
clear that field identification of these species based on coloration is 
unreliable because both species exhibit geographic variation in 
coloration (Brodie 1970, p. 503; Bury 1999, pp. 9-10).
    Researchers have cited morphological differences as evidence of a 
taxonomic distinction between Siskiyou Mountains salamanders and Del 
Norte salamanders. Perhaps the most convincing support for 
distinguishing between these forms was provided by Mead et al. (2005, 
pp. 165-166), who found that all three species in the Plethodon 
elongatus Complex differed in average measurements of male snout-vent 
length, forelimb length, and head width; and female snout-vent length, 
forelimb length, and internarial distance. Additionally, both Siskiyou 
Mountains salamanders and Scott Bar salamanders have a smaller modal 
number of costal folds and proportionally larger forelimbs than Del 
Norte salamanders, contributing to their more robust appearance 
(Highton and Brame 1965, p. 1; Mead et al. 2005, p. 170).
    Phylogenetic studies of the Plethodon elongatus Complex have 
provided further support for classifying Siskiyou Mountains salamanders 
and Del Norte salamanders as closely related species (Mahoney 2001, p. 
183; Mahoney 2004, pp. 155-161; Bury and Welsh 2005, p. 842; Mead et 
al. 2005, p. 166). Phylogenetic studies of these species have also 
shown that early studies of the morphology of Del Norte salamanders 
along the Klamath River between Happy Camp and Seiad Valley, 
California, were in fact describing Siskiyou Mountains salamanders 
(Pfrender and Titus 2001, p. 15; DeGross 2004, pp. 17-18; Mahoney 2004, 
p. 5; Mead et al. 2005, p. 173; Mead 2006, pp. 15-16). In fact, Bury 
(1973, p. 57) proposed possible intergradation between these two 
species, and Stebbins (1985, p. 47; 2003, pp. 173-174) demoted the 
Siskiyou Mountains salamander to a subspecies of Del Norte salamander. 
However, recent research suggests that little gene flow occurs between 
these species across their zone of contact in the Indian Creek drainage 
in western Siskiyou County, California (DeGross 2004, p. 40; DeGross et 
al. unpublished).
    Phylogenetic studies of the Siskiyou Mountains salamander have 
indicated that this species consists of two distinct genetic lineages: 
North Clade (populations within the Applegate River drainage and on the 
crest of the Siskiyou Mountain Range) and South Clade (populations 
south of the Siskiyou Mountain Range crest and adjacent to the Klamath 
River) (Pfrender and Titus 2001, pp. 5-6; DeGross 2004, pp. 24-44; 
Mahoney 2004, p. 8; Mead et al. 2005, pp. 163-166). A third, more 
divergent, group was also identified and is now recognized as a 
separate species, the Scott Bar salamander.
    Based on levels of genetic divergence between species in the 
Plethodon elongatus Complex, researchers estimated that the Del Norte 
salamander and Siskiyou Mountains salamander lineages diverged 
approximately 4 million years ago and that their shared ancestral 
lineage diverged from that of the Scott Bar salamander between 20 and 
26 million years ago (Mahoney 2004, p. 15; Mead et al. 2005, p. 165). 
Therefore, the Scott Bar salamander lineage appears to be the basal 
(most primitive, from which others are derived) lineage of the 
Plethodon elongatus Complex. Given the time periods during which these 
species diverged, speciation within this complex was probably 
influenced by Pleistocene glaciation (Soltis et al. 1997, pp. 369-370; 
Bury 1999, p. 22; DeGross and Bury unpublished).
    Differences between Scott Bar salamanders and the other members of 
the Plethodon elongatus Complex are not limited to their genetic 
divergence. As noted above, Mead et al. (2005, pp. 165-166) found 
differences in morphological measurements of all three species. 
Nonetheless, questions about the validity of the current classification 
of these species persist (sensu Wake and Jockusch 2000, p. 117). 
Further, the ranges of the Scott Bar salamander and Siskiyou Mountains 
salamander abut each other north of the Klamath River and south of 
Horse Creek, so it is possible that these species interbreed in this 
area. Measurements of gene flow between these species would be helpful 
to further clarify the taxonomy of southern populations of Siskiyou 
Mountains salamanders and Scott Bar salamanders and define the 
interspecific boundaries for each species range (DeGross and Bury 2007, 
p. 4; Wake and Jockusch 2000, p. 117).
    The Service recognizes that questions about the taxonomy of the 
Plethodon elongatus Complex remain and that research on this topic is 
ongoing. However, for the purpose of this finding, we evaluated the 
threats to the Siskiyou Mountains salamander and Scott Bar salamander 
separately because the preponderance of available evidence currently 
supports recognition of these forms as separate species. Even so, the 
ecological research on these species was

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conducted prior to recognition of the Scott Bar salamander as a 
separate species, and since both species are members of the Family 
Plethodontidae, their life histories and habitat associations appear to 
be similar. Therefore, for the purpose of this finding, we use the 
current literature describing the biological characteristics and 
ecology of the Siskiyou Mountains salamander for both species.
    For the purposes of this finding, we use the following hierarchy of 
taxonomic names:
    (1) Plethodon elongatus Complex: Plethodon salamanders within the 
geographic region occupied by Del Norte salamander, Siskiyou Mountains 
salamander, and Scott Bar salamander.
    (2) Siskiyou Mountains salamander Complex: The three known genetic 
entities previously classified as Siskiyou Mountains salamander, 
consisting of the Scott Bar salamander, Siskiyou Mountains salamander 
North Clade, and Siskiyou Mountains salamander South Clade.
    (3) Siskiyou Mountains salamander (North and South Clades 
combined), not including the Scott Bar salamander.
    (4) Individual genetic subunits of Siskiyou Mountains salamander: 
North Clade (hereafter referred to as the Applegate salamander) and 
South Clade (hereafter referred to as the Grider salamander).

Biology

    Like other members of the Family Plethodontidae, Siskiyou Mountains 
and Scott Bar salamanders require contact with moisture for respiration 
through their permeable skin (Feder 1983, pp. 292-293). Desiccation is 
lethal to Plethodon species and therefore, surface activity by Siskiyou 
Mountains and Scott Bar salamanders primarily occurs at night, when the 
air is cool and moist (Nussbaum 1974, p. 3; Nussbaum et al. 1983, p. 
103; Clayton and Nauman 2005, p. 139; Mead et al. 2005, p. 118). Peak 
periods of surface activity occur during the rainy season (usually late 
fall and spring) (Clayton and Nauman 2005, p. 139; Mead et al. 2005, p. 
118). These salamanders retreat to underground refugia during the 
extreme climatic conditions common during summer and winter in the 
eastern Klamath Mountains (Nussbaum 1974, p. 3). They may forage at the 
surface during the summer (Nussbaum et al. 1983, p. 103) but probably 
only in sites with relatively cool, moist microclimates. Little is 
known about these species' behavior, but many researchers assume that 
they are inactive underground and that foraging and reproduction only 
occur during brief periods of surface activity (Feder 1983, p. 305). 
However, it is possible that these activities also occur below the 
surface (Welsh and Lind 1992, p. 433). The limited surface activity by 
these species is reflected in survey protocols for Siskiyou Mountains 
salamanders, which require that surveys be restricted to periods of 
relative humidity above 65 percent, air temperatures between 39.2 and 
68 [deg]F (4 to 20 [deg]C), soil temperatures between 38.3 and 64.4 
[deg]F (3.5 to 18 [deg]C), and moist soil conditions (Clayton et al. 
1999, p. 133).
    Plethodon salamanders are fully terrestrial amphibians and do not 
need standing or flowing water for any stage of their life cycle (Zug 
et al. 2001, p. 383). Eggs are thought to be laid in small clusters 
deep in moist, rocky substrates, but this has not been observed by 
researchers. Females have clutches of 2 to 18 eggs, with an average of 
9 eggs per clutch (Nussbaum et al. 1983, pp. 21-23). Juveniles emerge 
in late fall and early spring. Welsh and Lind (1992, p. 432) reported 
that juveniles captured in mid-spring were significantly larger than 
would be expected if newly hatched. These salamanders appear to become 
reproductively mature at 5 to 6 years and are relatively long-lived (up 
to 15 years) (Nussbaum et al. 1983, p. 103; Clayton and Nauman 2005, p. 
139). Females appear to breed every other year (Nussbaum 1974, p. 22).
    Siskiyou Mountains and Scott Bar salamanders are `lie-and-wait' 
predators that prey on a variety of small terrestrial invertebrates, 
including spiders, pseudoscorpions, mites, ants, collembolans, and 
beetles (Nussbaum et al. 1983, p. 103). Seasonal changes in diet have 
been reported for these species (Nussbaum 1974, p. 24). Predators of 
these species have not been identified but may include snakes, shrews, 
or animals that opportunistically forage in spring leaf litter and 
debris (e.g., ground-foraging birds). Several researchers have 
hypothesized that interspecific and intraspecific competition are 
important factors in the population ecology of Siskiyou Mountains and 
Scott Bar salamanders (Nishikawa 1985, p. 1290; Mathis 1989, p. 790; 
Griffis and Jaeger 1998, p. 2500). These species' ranges overlap with 
those of ensatina (E. eschscholtzii oregonensis) and black salamanders 
(Aneides flavipunctatus), and a recent study described one site where 
they are sympatric with Del Norte salamanders (Mead 2006, p. 8). We are 
not aware of any information about parasites or diseases affecting 
these species or information about symbiotic or mutualistic 
interactions with other organisms.

Habitat Associations

    Siskiyou Mountains salamanders and Scott Bar salamanders occur on 
slopes with rocky soils or talus (loose surface rock) outcrops. These 
substrates provide interstitial spaces into which these animals can 
retreat from the climatic extremes of the eastern Klamath Mountains. 
These salamanders are occasionally found under other types of cover, 
such as bark, limbs, or logs, but only during wet weather when moisture 
is high and only in close proximity to suitable rocky substrates 
(Nussbaum 1974, p. 13; Nussbaum et al. 1983, p. 102). Like other 
plethodontids, Siskiyou Mountains salamanders and Scott Bar salamanders 
require contact with moisture for respiration through their skin. 
Therefore, habitat characteristics that influence forest microclimates, 
especially relative humidity and soil surface moisture, are likely 
important to these species. Based on these species' similar natural 
histories and physiologies (see ``Biology'' section), occurrence in the 
same region, and previous designation as one species, we assume that 
Siskiyou Mountains salamanders and Scott Bar salamanders have similar 
habitat requirements. As noted above, nearly all of the available 
information on these species comes from studies conducted on both 
species, prior to recognition of Scott Bar salamander as a separate 
species.
    Early observational studies of Siskiyou Mountains salamanders found 
that these animals are highly associated with talus and other rocky 
substrates (Highton and Brame 1965, p. 1; Storm 1966, p. 1; Nussbaum 
1974, p. 13; Clayton and Nauman 2005, p. 139; Mead et al. 2005, p. 
118). Nussbaum (1974, p. 13) found that the densest populations were on 
heavily wooded, north-facing slopes that also had talus deposits or 
fissured rock outcrops. Many of the earliest known populations of 
Siskiyou Mountains salamanders occurred in talus road cuts, where the 
underlying rock substrate was exposed and detection of salamanders was 
facilitated (Nussbaum 1974, p. 13).
    The degree to which Siskiyou Mountains salamanders and Scott Bar 
salamanders are associated with late-seral forest conditions has been 
the subject of considerable uncertainty and debate among scientists and 
land managers. Understanding this debate is essential to understanding 
the Service's finding for these species. The debate is exemplified by 
the salamander population at Muck-a-Muck Creek, the type locality from 
which the Scott Bar salamander was described (Mead et al. 2005, p. 
169). Biologists and researchers

[[Page 4384]]

use Muck-a-Muck as a ``reference site,'' a location with reliable 
salamander detections that can be checked prior to conducting surveys 
in other nearby areas to confirm that current weather conditions are 
within proper limits to conduct these surveys. However, even when 
survey conditions are adequate, salamanders may not be detected at this 
known reference site on any given single visit. Located adjacent to a 
road, the site experienced hydraulic mining in the late 1800s and 
currently supports a sparse overstory of young and early mature trees. 
These habitat conditions are representative of habitat at many 
locations occupied by apparently viable populations of Siskiyou 
Mountains salamanders (Bull et al. 2006, pp. 19-22; CDFG 2005, p. 24; 
Farber 2007a, pp. 3-4). The regularly reported existence of salamander 
populations at sites like the Muck-a-Muck Creek site undercuts the 
conclusion of some researchers (based on the results of a single study) 
that the species is dependent on old-growth forest (Ollivier et al. 
2001, pp. 26-29; Welsh et al. 2007a, p. 31).
    The results of studies of habitat relationships conducted to date 
are equivocal or provide limited inferences. Limited inferences result 
from either (1) lack of a random or systematic sampling design that 
allows inference to a larger population, or (2) single-visit sampling 
that fails to incorporate the low and variable detection rates 
associated with these species. Two analyses of a single, relatively 
large-scale, single-visit, random, sampling-based study suggested an 
association with closed-canopy, older forest (Ollivier et al. 2001; 
Welsh et al. 2007a), whereas field studies evaluating habitat 
attributes at known (not randomly or systematically selected) locations 
demonstrated that the species are found in a wide range of forest 
structural conditions (Farber et al. 2001; Bull et al. 2006; Farber 
2007a). We are not aware of any rigorous studies evaluating the 
species' demographic responses to forest conditions.
    The most rigorous research of these species' habitat associations 
was conducted by Ollivier et al. (2001) and Welsh et al. (2007a). These 
studies used the same data set and somewhat different analytical 
techniques. The data used in both analyses were collected at 61 sites 
occupied by Siskiyou Mountains salamanders and possibly Scott Bar 
salamanders (a few sites were located within the range of what were 
later recognized as Scott Bar salamanders). These sites were compared 
with sites classified as unoccupied by salamanders (see below). These 
studies found that salamander populations on either side of the 
Siskiyou Crest appeared to occupy habitat based on different 
environmental factors (Welsh et al. 2007a, p. 28). The authors 
primarily attributed this result to geographic differences in 
precipitation, illumination (topographic variation in sunlight or 
shading), and vegetation (Welsh et al. 2007a, pp. 19, and 28). Based on 
these differences, they suggested that suitable habitat is less 
abundant and more patchily distributed on the south side of the crest 
than on the north side (Welsh et al. 2007a, p. 28). Although these 
results differed somewhat for salamanders on either side of the 
Siskiyou Crest, they generally indicated that sites occupied by 
salamanders contained attributes that likely moderate surface 
microclimates for these animals (e.g., greater canopy closure, more 
leaf litter cover, more decaying logs) or that are associated with 
moist, cool microclimates (e.g., less grass cover, more sword fern 
cover) (Ollivier et al. 2001, pp. 17-21, 26-29; Welsh et al. 2007a, pp. 
24, 27). Both analyses concluded that Siskiyou Mountains (and possibly 
Scott Bar) salamanders are ``a mature to old-growth-forest-associated 
species that exists at its biological optimum under conditions found 
primarily in later seral stages of mixed conifer-hardwood forests in 
northwestern California and southwestern Oregon'' (Ollivier et al. 
2001, p. 42; Welsh et al. 2007a, p. 31). However, the authors also 
state that ``[t]oday, information on the habitat requirements of this 
species is incomplete and conflicting'' (Welsh et al. 2007a, p. 16) and 
``[m]any of the biotic and abiotic requirements necessary for long-term 
viability for the Siskiyou Mountains salamander remain undetermined'' 
(Welsh et al. 2007a, p. 31). It is important to note that the results 
of these studies only indicate correlations between forest attributes 
and the presence of salamanders; they do not actually demonstrate that 
these species select habitat based on older-forest characteristics 
(Welsh et al. 2007a, p. 31). For example, these salamanders may select 
habitat based on other factors (e.g., suitable microclimates) that 
often occur within older forests but that can also occur in other areas 
such as deep drainages and north-facing slopes.
    Our understanding of the habitat associations of Siskiyou Mountains 
salamander and their degree of ecological dependence on specific 
habitat conditions is hampered by the difficulty in detecting this 
species during surveys. Their brief, intermittent periods of surface 
activity, nocturnal habits, and secretive behavior make detection of 
Siskiyou Mountains salamanders and Scott Bar salamanders difficult 
(Nussbaum 1974, p. 3; Olson et al. 2007, pp. 7-8). Welsh et al. (2007a, 
p. 25) estimated that their detection rates for these species were 20 
and 28 percent on the south and north slopes of the Siskiyou Crest, 
respectively. Detection rates for other Plethodon species are similarly 
low: 15 percent (Bailey et al. 2004, p. 21) and 2 to 32 percent (Taub 
1961, p. 695). Because detection rates are low for these species, 
repeated surveys and estimation of the probability of false negatives 
during surveys are required to minimize or account for the probability 
of classifying occupied sites as unoccupied. The survey protocol 
developed for the NWFP Survey and Manage Guidelines (Clayton et al. 
1999, p. 141) requires three survey visits to determine presence or 
absence of Siskiyou Mountains salamanders. Classifying occupied sites 
as unoccupied, or failing to account for the probability of doing so, 
can bias conclusions about relationships between salamanders and 
habitat characteristics. The presence or absence data analyzed by 
Ollivier et al. (2001) and Welsh et al. (2007a) were collected with a 
single-visit protocol, so these studies cannot reliably infer absence 
at sites where detections were not obtained. In fact, the California 
Department of Fish and Game (CDFG) used a more intensive survey 
protocol to resurvey 13 clear-cut or precanopy (0 to 30 years-old) 
sites classified as unoccupied by Ollivier et al. (2001) and Welsh et 
al. (2007a) and found Siskiyou Mountains salamanders at 5 sites, Scott 
Bar salamanders at 2 sites, and Del Norte salamanders at 1 site (Bull 
et al. 2006, p. 25). While this finding does not appear to change the 
general conclusion described by Ollivier et al. (2001) and Welsh et al. 
(2007a) that salamanders were more likely to be detected in closed-
canopied older forest than in more open sites, it acts to substantially 
weaken the inference of Ollivier et al. (2001, p. 42) and Welsh et al. 
(2007a, p. 31), that these species are ecologically dependent on 
conditions primarily found in mature or late-seral stage forests.
    Two other studies have examined potential relationships between 
habitat attributes and abundances of Siskiyou Mountains salamanders and 
Scott Bar salamanders. Farber (2007a) described sites occupied by Scott 
Bar salamanders on private timber company property and adjacent 
National Forest land. This study compared salamander abundances and 
habitat characteristics at 26 sites

[[Page 4385]]

within a relatively small area (29 acres (ac) (11.7 hectares (ha))) and 
found that salamander abundance was only significantly related to 
percent rock cover. A large proportion of the occupied sites (94 
percent) had evidence of at least one previous manmade or natural 
disturbance (Farber 2007a, p. 3). Bull et al. (2006) described CDFG 
surveys at 68 sites occupied by Siskiyou Mountains or Scott Bar 
salamanders. Eighty-seven percent of these sites were on private 
timberlands, and the remaining sites were on Federal lands (Bull et al. 
2006, p. 24). Like Farber (2007a), CDFG found evidence of previous 
disturbance at most (82 percent) occupied sites (Bull et al. 2006, p. 
24). Roughly 83 percent of the sites occurred in forest stands with 
relatively open canopies (less than 60 percent canopy closure). They 
also found that salamander sites occurred within a wide range of 
environmental conditions, including all slope aspects and nearly all 
(16 of 18) California Wildlife Habitat Relationships tree size and 
canopy classes (Bull et al. 2006, p. 24). These studies' sampling 
designs preclude inferences about the habitat preferences of other 
Siskiyou Mountains salamander populations because they were focused on 
known salamander sites and did not take into account the broad range of 
habitat that is potentially available to these salamander species. 
However, both studies showed that Siskiyou Mountains salamanders and 
Scott Bar salamanders occur within a relatively wide range of forest 
conditions, and were not extirpated by the disturbances (timber 
harvest) that created those conditions.
    To support their argument that the Siskiyou Mountains salamander is 
critically imperiled by habitat loss, the petitioners rely heavily on 
statements made by Welsh et al. (2007a) as providing new scientific 
information that the salamanders are highly associated with, and 
ecologically dependent on, old-growth forest conditions, and the 
petitioners highlight an ongoing debate between Dr. Welsh and the CDFG 
(Greenwald and Curry 2007, pp. 4-7). As discussed above, we conclude 
that the survey methodology employed by Ollivier et al. (2001) and 
Welsh et al. (2007a, p. 18) was inadequate to rigorously determine 
salamander absence as required for the presence-absence statistical 
modeling method used to analyze the data. The single-visit sampling 
methodology these authors employed is more appropriate for comparisons 
of relative abundance among habitat types, which is how we interpreted 
their results. The fact that salamanders were subsequently detected by 
CDFG at over half of the `absent' sites analyzed by Welsh et al. 
(2007a) does not negate the importance of this study or the habitat 
associations it describes; it does, however, limit the strength of 
inference regarding the degree to which Siskiyou Mountains salamanders 
may require old-growth forest conditions. We do not consider the field 
studies conducted by CDFG (Bull et al. 2006) as providing competing 
scientific research requiring reconciliation with the statistical 
design of the Welsh et al. (2007a) study. The CDFG field studies do, 
however, provide habitat results from a large sample of occupied 
salamander locations, which, in combination with similar data sets from 
Farber et al. (2001), constitute a significant source of information on 
these species.
    A model was recently developed for predicting the occurrence of 
Siskiyou Mountains salamanders north of the Siskiyou Crest (Reilly et 
al. 2007). This model incorporated three variables reported by Ollivier 
et al. (2001) and Welsh et al. (2007a) to be positively related to 
occupancy by Siskiyou Mountains salamanders: rocky soil types, forest 
canopy closures above 70 percent, and conifer forest with average tree 
sizes greater than 17 inches (43 centimeters) in diameter at breast 
height (DBH) (Reilly et al. 2007, p. 1). An additional variable 
modeling topographical variation in sunlight or shading was also 
incorporated (Reilly et al. 2007, p. 2). Strategic surveys of sites 
that were predicted by the model to be occupied had 65 percent 
detection rates (34 of 52 sites were occupied), the highest ever 
reported for this species (Nauman and Olson 2004, p. 3). In addition to 
indicating the usefulness of presence or absence modeling as a 
scientific and management tool, this relatively high detection rate 
seems to support the associations described by Ollivier et al. (2001) 
and Welsh et al. (2007a).

Summary of Habitat Associations

    Few studies of the habitat associations of Siskiyou Mountains 
salamanders and Scott Bar salamanders have been conducted. These 
include only a single large, systematic sample effort, from which two 
analyses were conducted (Ollivier et al. 2001 and Welsh et al. 2007a). 
These analyses found positive relationships between detection of 
Siskiyou Mountains salamanders (and possibly Scott Bar salamanders) and 
habitat characteristics that likely moderate surface microclimates for 
them (e.g., high canopy closure, more leaf litter cover, more decaying 
logs). Studies by Farber et al. (2001), Farber (2007a), and CDFG (Bull 
et al. 2006) were smaller and less rigorous than the analyses by 
Ollivier et al. (2001) and Welsh et al. (2007a). However, they clearly 
showed that Siskiyou Mountains salamanders and Scott Bar salamanders 
occur within a wide range of habitat conditions, including clear-cuts 
and young forest. The limited available evidence suggests that these 
species are highly associated with talus and fissured rock outcrops and 
are generally associated with moist, cool surface microclimates. These 
salamanders are likely more common in mature and old-growth forest than 
in other forest classes, but many salamander sites occur in other 
habitat types. Potential differences in the size and viability of 
populations in open or disturbed habitat and mature or old-growth 
habitat are discussed below under Factor A.

Range and Extant Distribution

Range

    Currently known populations within the Siskiyou Mountains 
salamander Complex occur within Jackson County and the extreme 
southeast portion of Josephine County in southwestern Oregon, and in 
northern Siskiyou County in northwestern California. In Oregon, known 
populations occur in the Applegate Valley watershed north of the 
Siskiyou Crest. In California, the species complex occurs in the 
Klamath River drainage, south of the Siskiyou Crest, in the area 
bounded to the west by Indian Creek and the headwaters of Grider Creek, 
Kelsey Creek, and Canyon Creek; to the south by Scott Bar Mountain; and 
to the east by the headwaters of Mill Creek and the Horse Creek 
drainage. This range is subdivided into three areas based on 
genetically distinct populations. Siskiyou Mountains salamander North 
Clade (or Applegate Population) occupies the area north of the Siskiyou 
Crest; Siskiyou Mountains salamander South Clade (or Grider Population) 
occurs south of the Siskiyou Crest; and the Scott Bar salamander is 
found in the southeastern portion of the former range of Siskiyou 
Mountain salamander South Clade.
    Boundary lines for the ranges of the members of the Siskiyou 
Mountains salamander Complex have been variously estimated by several 
authors (DeGross 2004, p. 15; Nauman and Olson 2004, p. 2; 2007, p. 4) 
and have changed through time as additional populations were discovered 
and results of genetic analyses were obtained. For the purposes of this 
finding, we delineated species' ranges and calculated landscape 
statistics based on

[[Page 4386]]

range boundaries proposed by Nauman and Olson (2007, p. 4) but we 
slightly modified these boundaries based on new species locations, 
watershed boundaries, and distribution of suitable habitat. Based on 
the locations of genetic samples of Scott Bar salamanders, we estimated 
its range to incorporate the southeastern portion of the former 
Siskiyou Mountains salamander's range. However, the uneven distribution 
of surveys and small number of locations with genetic confirmation 
creates uncertainty as to the actual extent of the Scott Bar 
salamander. The resulting estimated range (136,740 ac (55,335 ha)) is 
considerably larger than previous estimates that were based on a small 
number of genetically confirmed locations; some of this expansion is 
the result of confirmation of one Scott Bar salamander location in the 
Walker Creek drainage (DeGross 2007). Several watersheds in the 
southern portion of the estimated range delineated by Nauman and Olson 
(2007, p. 4) do not have records of Siskiyou Mountains or Scott Bar 
salamander locations. Review of these areas by species experts (Cuenca 
2007; Clayton 2007) indicated that surveys have not been conducted 
there, but suitable habitat is widespread. Additional surveys and 
genetic analyses are necessary to adequately delineate the southern 
boundary of the Scott Bar salamander and Siskiyou Mountains salamander. 
Our estimates of species' ranges are intended for use in evaluating 
species' distribution across various land ownership and Federal land 
allocations; they are not intended to represent precise estimates of 
occupied habitat.
    Our understanding of the range and distribution of the Siskiyou 
Mountains salamander Complex is dynamic; the known range has roughly 
tripled between 1980 and 2007, doubling between 1993 and 1998 (Olson et 
al. 2007, p. 20). Biologists familiar with the species believe that the 
currently known range is well-defined to the east by xeric conditions 
and unsuitable soil types, and to the west by the range of the Del 
Norte salamander (Olson et al. 2007, p. 19). However, it is likely that 
the known range will continue to be refined and expanded through 
discovery of additional populations to the south in the Scott River, 
Canyon Creek, Kelsey Creek, and Upper Grider Creek drainages, and to 
the north in the Applegate River drainage. For example, two detections 
of salamanders described as Siskiyou Mountains salamanders were 
reported by a Survey and Manage Guidelines survey crew near the town of 
Rogue River in 2006 (DeGross 2007). If confirmed, these detections 
would represent a range expansion of roughly 5 miles (mi) (8.45 
kilometers (km)).
    We were unable to find any information suggesting that the occupied 
range of any member of the Siskiyou Mountains salamander Complex is 
different from its historical range. Many occupied locations exist 
within watersheds that have sustained considerable physical 
modification by historical mining, roadbuilding, and logging. As 
described above, the species' ranges appear to be defined by climatic 
conditions, soil and parent material type, and the adjacent Del Norte 
salamander (Olson et al. 2007, p. 19).

Distribution

    The distribution of Siskiyou Mountains and Scott Bar salamander 
populations within their respective species' ranges is poorly known. 
With the exception of systematic surveys conducted by Ollivier et al. 
(2001) and Nauman and Olson (2004a and 2004b), the majority of surveys 
have been opportunistic or conducted in support of timber management 
planning activities. Large areas within the species' known ranges 
remain unsurveyed due to poor access or lack of planned projects 
requiring surveys. The lack of systematic surveys may result in biased 
estimates of population distribution. For example, because CDFG 
requires surveys for Siskiyou Mountains salamanders and Scott Bar 
salamanders during the Timber Harvest Plan (THP) review process, a high 
proportion (40 percent) of known Scott Bar salamander locations have 
been reported on private timberlands, which accounts for only 22 
percent of the known range of the species (see Table 1 below).

 Table 1.--Proportion of Land Ownership Within the Estimated Ranges of Siskiyou Mountains Salamanders (SMS) and
                                           Scott Bar Salamanders (SBS)
----------------------------------------------------------------------------------------------------------------
                                                                                         Scott Bar
                                                               Applegate    Grider SMS   salamander    SMS-SBS
                                                                SMS (%)        (%)          (%)      complex (%)
----------------------------------------------------------------------------------------------------------------
Private Lands...............................................           15            9           22           15
Federal Lands:
    USFS....................................................           66           91           78           76
    BLM.....................................................           19            0            0            9
        Total Area (ac).....................................      248,870      174,285      136,740      559,895
        Total Area (ha).....................................      100,712       70,529       55,335      226,578
----------------------------------------------------------------------------------------------------------------

    Population distribution is strongly influenced by the abundance and 
distribution of suitable talus habitat. Using a Geographic Information 
System (GIS)-based predictive model, the Survey and Manage Guidelines 
Species Review Panel for Siskiyou Mountains salamanders estimated that 
roughly 30 percent of the known range north of the Siskiyou Crest 
consisted of high-quality talus habitat (USDA and USDI Species Review 
Panel 2002), but pre-disturbance surveys conducted in the same area 
found that 3 to 14 percent of a given planning area (10,000 to 15,000 
ac (4,047 to 6,070 ha)) consisted of suitable rock substrate (USDA and 
USDI Species Review Panel 2001). Based on surveys and mapping of rock 
habitat, Timber Products Company estimated that approximately 18 
percent of their surveyed lands within the range of the Scott Bar 
salamander was composed of suitable talus habitat (Farber 2006). Using 
a similar methodology, Fruit Growers Supply Company (2007) estimated 
that 19 percent of 2,615 ac (1,058 ha) surveyed within the range of the 
Applegate Population of the Siskiyou Mountains salamander was composed 
of suitable talus habitat.
    The Siskiyou Mountains salamander Complex occurs within a roughly 
500,000 ac (202,346 ha) area dominated by Federal lands (see Table 1). 
The range of the Applegate Population (North Clade) of the Siskiyou 
Mountains salamander occurs within 248,870 ac (100,712 ha), consisting 
primarily (85 percent) of Federal lands, and more than 90 percent of 
the 174,285 ac (70,529 ha) range of the Grider Population (South Clade) 
of the Siskiyou Mountains salamander occurs on Federal lands (see

[[Page 4387]]

Table 1). The Scott Bar salamander has the smallest range, covering 
approximately 136,740 ac (55,335 ha), and occurs on the smallest 
proportion of Federal lands (78 percent) within the complex (see Table 
1).
    Known populations appear to be well-distributed across their 
respective species' ranges. To evaluate spatial distribution of 
salamander locations within each species' range at a coarse scale, we 
compared known locations to watershed boundaries within each species' 
range. Site locations of the Applegate Population of the Siskiyou 
Mountains salamander occur within 19 of the 21 watersheds that 
constitute the range of this group. The range of the Grider Population 
of the Siskiyou Mountains salamander is composed of 36 watersheds of 
which 23 (64 percent) contain known populations. The 13 watersheds 
without known salamander locations are primarily situated in Wilderness 
and Roadless areas where access is difficult and few surveys have been 
conducted. Known locations of Scott Bar salamanders occupy 17 of the 25 
watersheds within their range. Of the eight watersheds without known 
locations, six are within Wilderness and Roadless areas where suitable 
habitat exists but surveys have not been conducted.
    Nauman and Olson (2007) conducted surveys at a stratified random 
sample of points located on Federal lands within the range of the 
Grider Population of the Siskiyou Mountains salamander and the Scott 
Bar salamander. They found occupancy rates (presence or absence) to be 
similar at high-elevation (greater than 4,000 feet (ft) (1,219 meters 
(m)) sites and low-elevation (less than 4,000 ft (1,219 m)) sites, but 
relative abundance (captures per person, per hour) at low-elevation 
sites was roughly twice that at high elevation. The authors conducted a 
single survey visit per site during one season, and did not evaluate 
the potential effect of variable detection probabilities at different 
elevations on their results, which, as noted above, may underestimate 
the number of animals actually present; however, their findings suggest 
that these salamanders may be less abundant or less detectable at 
higher elevations.

Population Size and Trend

    Evaluation of potential population sizes for the Siskiyou Mountains 
salamander and Scott Bar salamander is strongly influenced by the 
species' low detectability and the amount and distribution of 
potentially suitable habitat. Because of their secretive habits, 
detection rates for these salamanders are very low, even though the 
species may be locally quite abundant (Nussbaum 1974, p. 3; Clayton et 
al. 1999, p. 133). Results of surveys within habitat known to be 
occupied are frequently negative (Clayton et al. 2004, p. 10; CDFG 
2005, p. 10). Individual populations likely range in size from a few 
individuals to thousands of individuals (Nussbaum 1974, p. 16; Welsh 
and Lind 1992, p. 96). Based on extrapolation of salamander densities 
obtained during intensive field surveys, Nussbaum (1974, p. 16) 
provided a species-wide ``conservative estimate'' of over 3 million 
Siskiyou Mountains salamanders, and opined that the actual abundance 
could be 10 times as high. While the author acknowledged that a number 
of methodological problems may affect this estimate, it nonetheless 
suggests that the perceived rarity of this species may be more related 
to low detectability than to actual population size.
    Our current understanding of population sizes for Siskiyou 
Mountains salamander and Scott Bar salamander is based primarily on the 
cumulative number of occupied sites or locations that have been 
reported over time. However, these numbers may be misleading for 
several reasons. At many locations, particularly sites detected during 
project surveys under Survey and Manage Guidelines, no attempt was made 
to determine population size; detection of a single individual was 
adequate to define an occupied site. Because of this, large habitat 
patches potentially supporting many individual salamanders are counted 
as equivalent to small habitat patches or detections of dispersing 
individuals. In addition, large areas of suitable habitat remain 
unsurveyed, particularly in Wilderness, Roadless Areas, and Late-
successional Reserves where access is poor or project surveys are 
typically not conducted (Late-successional Reserves are a NWFP land 
allocation designed to serve as habitat for late-successional- and old-
growth-related species). For example, approximately 10 percent and 26 
percent of the range of the Scott Bar salamander and Grider salamander, 
respectively, is classified as ``Roadless Area.'' Finally, known 
locations are frequently spatially clumped, and no uniform effort to 
distinguish between individual populations has been undertaken. 
Agencies and researchers involved with these species employ several 
criteria (e.g., 164 to 492 ft (50 to 150 m) spacing, presence of 
perennial stream or area of unsuitable habitat) to imply separation 
between occupied locations or ``populations.'' For these reasons, the 
currently known numbers of Siskiyou Mountains salamanders and Scott Bar 
salamanders are more representative of the distribution and intensity 
of survey efforts than of actual salamander populations.
    The numbers of known locations of Siskiyou Mountains salamanders 
and Scott Bar salamanders have increased steadily since the discovery 
of these species. For example, the number of known locations of Scott 
Bar salamanders on lands managed by Timber Products Company increased 
from 8 in 1997 to 36 in 2007 (Farber 2007c). To describe the number and 
distribution of known salamander locations, we obtained location data 
from Federal and State agencies and private timber companies and 
combined them into a single GIS layer. Because of variability in 
methods used by various agencies to delineate individual locations 
(many locations were clumped less than 328 ft (100 m) apart), we 
evaluated the proximity of adjacent locations and retained only 
locations greater than 328 ft (100 m) apart, to minimize the inclusion 
of multiple records at discrete locations. The resulting numbers are 
intended to represent individual populations, but likely still contain 
multiple records from large habitat patches and likely differ from 
previous estimates based on dissimilar mapping methods.
    Within each of the genetic subunits in the Siskiyou Mountains 
salamander Complex, the number of locations with individuals that have 
been genetically confirmed to the species level is much smaller than 
the overall number of known locations. For example, the estimated range 
of the Scott Bar salamander is defined on the basis of 23 genetically 
confirmed locations from the samples of Mahoney, Mead, and DeGross; 
however, the defined range of the species contains 98 additional 
salamander locations previously attributed to the Grider salamander. 
Because populations of the two species tend not to overlap (Mead 2006, 
p. 10), it is reasonable to conclude that all salamander detections 
within what is now known to be the range of the Scott Bar salamander 
are Scott Bar salamanders. For the purposes of this finding, we used 
the total number of individual locations within each species' range, 
recognizing that ongoing genetic studies may modify the boundaries of 
these subunits, and therefore the number of known individual sites 
within each genetic subgroup.

[[Page 4388]]



  Table 2.--Number of Known Locations and Percent of Total Known Siskiyou Mountains Salamanders (SMS) and Scott
                               Bar Salamanders (SBS) on Federal and Private Lands
----------------------------------------------------------------------------------------------------------------
                                                                                     Scott Bar        SMS-SBS
                                                   Applegate SMS    Grider SMS    salamander \1\      complex
----------------------------------------------------------------------------------------------------------------
Federal lands...................................       376 (85%)        74 (97%)        69 (60%)       519 (82%)
Private Lands...................................        64 (14%)          2 (3%)        46 (40%)       112 (18%)
                                                 ---------------------------------------------------------------
    Total.......................................             440              76             115            631
----------------------------------------------------------------------------------------------------------------
\1\ Number of known Plethodon sp. locations within the presumed range of the Scott Bar salamander.

Density

    Population densities for the Siskiyou Mountains salamander Complex 
are poorly known. Estimation of population density for these 
salamanders is hindered by low detectability and highly variable 
environmental or habitat conditions during surveys (Nussbaum 1974, p. 
15). Densities recorded during the habitat associations study conducted 
by Ollivier et al. (2001, p. 16) ranged from 1 to 13 animals per 527-
ft\2\ (49-m\2\) search plot (i.e., 0.02 to 0.33 animals per m\2\); 
whereas Nussbaum (1974, p. 16) recorded 0.53 animals per m\2\ during an 
intensive field study. Nauman and Olson (2007, p. 19) reported an 
average of 0.01 salamanders per m\2\ and 2.39 salamanders per person, 
per hour in California, with capture rates ranging from 2.83 
salamanders per person, per hour at lower elevations to 1.25 
salamanders per person, per hour at higher elevation sites. An 
inventory of all known Siskiyou Mountains salamander sites on the 
Applegate Ranger District in 1992 reported abundances of salamanders 
ranging from 0.3 to 11 salamanders per person, per hour (Olson et al. 
2007, p. 13). None of these studies was designed to estimate salamander 
density, and mark-recapture studies that would permit estimation of 
density have not been conducted.

Population Trend

    We were unable to locate any information describing population 
trends for the Scott Bar salamander or Siskiyou Mountains salamander 
(or either of its constituent populations). Several authors have 
inferred population declines based on observations of habitat 
modification within occupied areas (Ollivier et al. 2001, p. 5; Welsh 
2005, pp. 5-7), but their study design did not support this type of 
inference.

Land Management

    Populations of Siskiyou Mountains salamanders and Scott Bar 
salamanders receive an added layer of security from several 
conservation efforts on Federal lands. The majority of the Siskiyou 
Mountains salamander Complex occurs within lands administered under the 
provisions of the NWFP (USDA and USDI 1994) (see Table 1 above), which 
was established to provide an ecosystem-based management strategy for 
late-successional forests and the wildlife species that inhabit them 
(USDA and USDI 1994). The NWFP consists of two primary parts that 
concern salamander conservation: (1) A system of land-use allocations 
with associated Standards and Guidelines to guide land management; and, 
(2) until recently, the Survey and Manage Mitigation Measure Standards 
and Guidelines, which provided species-specific management guidance for 
certain groups of species. The NWFP Record of Decision (ROD) was 
implemented as amendments to all existing land and resource management 
plans for the Bureau of Land Management (BLM) and USFS within the range 
of the northern spotted owl.
    Lands administered by the USFS and BLM are divided into five 
primary categories of land management under the NWFP: Late-successional 
Reserves, Congressionally Reserved Areas, Riparian Reserves, Adaptive 
Management Areas, and Matrix. Late-successional Reserves are 
established with an objective to protect and enhance conditions of 
late-successional and old-growth forest ecosystems, which serve as 
habitat for late-successional, forest-related species. Forest 
management activities are highly restricted within Late-successional 
Reserves. Congressionally Reserved Areas, such as Wilderness Areas, 
Wild and Scenic Rivers, and National Monuments, are incorporated into 
the design of the Late-successional Reserve System. Riparian Reserves 
provide an area along all streams, wetlands, lakes, ponds, and unstable 
areas where riparian-dependant resources receive primary management 
emphasis. Maintenance of forested conditions in Riparian Reserves for 
shading and water quality is also expected to contribute to dispersal 
and breeding habitat for late-successional species. Adaptive Management 
Areas (AMAs) are established to develop and test new management 
approaches and timber harvest methods to integrate and achieve 
ecological and economic health, and other social objectives. Matrix 
lands consist of those Federal lands outside of the four other 
categories described above. Production of timber and other commodities 
is an important objective for Matrix lands. However, forests in the 
Matrix also provide connectivity between Late-successional Reserves and 
function as habitat for a variety of forest-dwelling species. The NWFP 
Matrix Standards and Guidelines are designed to provide for important 
ecological functions such as dispersal of organisms, carryover of some 
species from one stand to the next, and maintenance of ecologically 
valuable structural components such as logs, snags, and large trees. 
The Matrix also provides ecological diversity by providing early-
successional habitat. Within Matrix, other land use allocations such as 
Visual Emphasis Areas, Managed Wildlife Areas, and Retention Areas 
carry additional restrictions on timber harvest and to some degree 
function as reserves.

  Table 3.--Federal Land Allocations Within the Estimated Ranges of the Siskiyou Mountains Salamander (SMS) and
                                           Scott Bar Salamander (SBS)
----------------------------------------------------------------------------------------------------------------
                                                            Applegate                   Scott Bar      SMS-SBS
                                                               SMS       Grider SMS    salamander      complex
----------------------------------------------------------------------------------------------------------------
Total area in ac (ha)...................................      248,870       174,285       136,740       559,895
                                                             (100,712)      (70,529)      (55,335)     (226,578)

[[Page 4389]]

 
Private Lands (%).......................................           15             9            22            15
Federal Lands (%):
    Reserves............................................           33            73            51            50
    Adaptive Management Area \1\........................           42             0             0            19
    Matrix-retention \2\................................            1            13            19             9
    Matrix-general forest \3\...........................            9             5             8            7
----------------------------------------------------------------------------------------------------------------
\1\ Experimental management to meet ecological, economic, and social goals.
\2\ Timber harvest restricted to accommodate various other management goals.
\3\ Timber production is a high priority.

    Roughly 33 percent of the range of the Applegate salamander occurs 
within reserves (Late-successional Reserves, Wilderness, Riparian 
Reserves, and other land allocations withdrawn from scheduled timber 
harvest), 42 percent of the range within the Applegate Adaptive 
Management Area, 9 percent in Matrix, and 15 percent on private lands 
(see Table 3 above). Nearly three-quarters of the range of the Grider 
salamander is in reserves, and 18 percent is in Matrix; however, almost 
three-fourths of the Matrix is in land-use allocations (retention 
areas) where timber harvest is restricted (USDA 1994, pp. 4-73 to 4-
176). Fifty-one percent of the Scott Bar salamander's range is in 
reserves, and an additional 19 percent occurs within retention areas 
(Wild and Scenic Rivers, Retention Visual Quality Objective). Overall, 
only approximately 14 percent of the range of the Applegate salamander, 
24 percent of the range of the Grider salamander, and 30 percent of the 
range of the Scott Bar salamander are composed of Matrix-General Forest 
and private timberlands, where intensive timber management would be 
expected to occur. However, because varying levels of timber management 
occur within the Applegate Adaptive Management Area in the range of the 
Applegate salamander, up to about 66 percent of this species' range is 
available for various levels of timber harvest and cannot be considered 
to be reserve lands.
    Little is known about the actual distribution of salamander 
populations among the land-use allocations described above. Nauman and 
Olson (2007) attempted to evaluate the occurrence of Grider salamanders 
and Scott Bar salamanders by conducting surveys at a stratified random 
sample of points in reserved and matrix land allocations at high 
(greater than 4,000 ft (1,219 m)) versus low (less than 4,000 ft (1,219 
m)) elevation. They found that capture rates for these species were 
higher on matrix lands, likely because a higher proportion of reserved 
lands occur at higher elevations, which are less suitable for the 
species. The authors concluded that reserved land allocations may not 
provide adequately for conservation of the species but described a 
number of sampling issues (single-visit protocol, unequal sampling of 
strata) that may weaken this conclusion.

Survey and Manage Mitigation Measure Standards and Guidelines

    In addition to the NWFP's system of land-use allocations and 
management standards and guidelines, specific mitigation measures were 
included for about 400 rare or poorly known species. We refer to this 
broadly as the Survey and Manage Program. The Survey and Manage Program 
contains an adaptive management provision, establishing the Species 
Review Process wherein species experts (``taxa teams'') evaluate and 
synthesize the latest information about each species. Reports from the 
taxa teams are then used by the agencies to propose changes to 
management of these taxa, as appropriate. The Siskiyou Mountains 
salamander was included in the original list of Survey and Manage 
species under Survey Strategies 1 and 2 (USDA and USDI 1994, pp. C-59, 
C-45). Survey and Manage guidelines for these salamanders required that 
known salamander sites be managed via protection buffers (Strategy 1), 
and that surveys be conducted prior to ground-disturbing activities 
such as timber harvest (Strategy 2). Protection buffer standards and 
guidelines for Siskiyou Mountains salamanders required the retention of 
all overstory trees within a buffer of at least the height of one site-
potential tree or 100 feet horizontal distance, whichever is greater, 
surrounding the location. As a result of the 1999 Species Review 
Process, the Siskiyou Mountains salamander was reclassified as a 
Category C species in the Final Supplemental Environmental Impact 
Statement (FSEIS) for the NWFP (USDA and USDI 2000, Appendix F; p. 
101). Criteria for including a taxon in Category C are: (1) There is 
not a high concern for persistence; (2) it is likely that not all known 
sites are necessary for reasonable assurance of persistence of the 
taxon; (3) the taxon is uncommon (as opposed to rare); and (4) pre-
disturbance surveys are required until a population network is 
established. The management objective for the Siskiyou Mountains 
salamander under Category C is to identify and manage high-priority 
sites to provide for reasonable assurance of persistence. The current 
status of the Siskiyou Mountains salamander was assigned in the March 
14, 2003, Implementation of the 2002 Annual Species Review Memorandum 
(USDA and USDI 2003). Because of their smaller number of known sites 
and patchy distribution, salamander populations south of the Siskiyou 
Crest were assigned to Category A, requiring pre-disturbance surveys 
and management of protection buffers for all known sites. Northern 
populations were assigned to Category D. Management objectives for 
Category D species are to identify and manage high-priority sites to 
provide for a reasonable assurance of species persistence; pre-
disturbance surveys are not required.
    The USFS and BLM have determined to remove the Survey and Manage 
Program, and in July 2007 published their Record of Decision (2007 ROD) 
to implement this decision (see ``Summary of Factors Affecting the 
Species: Factor D''). Therefore, at this time, the Survey and Manage 
Program has been eliminated for project planning and new decisions. 
However, because of the lag time in implementation of the 2007 ROD, 
most new Federal land management decisions issued in 2008 will be 
compliant with the Survey and Management guidance for the Siskiyou 
Mountains salamander (West 2007); implementation of new projects 
compliant with the 2007 ROD is unlikely until 2009. We therefore view

[[Page 4390]]

the Survey and Manage guidelines as existing habitat management until 
after 2008. Unless the 2007 ROD is successfully challenged in court, 
project decisions after 2008 will no longer contain protections 
currently provided by the Survey and Manage provisions.
    The Survey and Manage guidelines have provided additional security 
for salamander populations across the vast majority of the range of the 
Siskiyou Mountains salamander. With the removal of the Survey and 
Manage Guidelines under the 2007 ROD, management of these species will 
be based on the USFS's Special Status Species Program and the BLM's 
Sensitive Species Program (Hughes 2007). The Special Status Species and 
Sensitive Species programs are anticipated to provide less stringent 
protections than those in the Survey and Manage Program; however, they 
include provisions for development of Conservation Strategies and 
Conservation Agreements.
    Based on ecological and management information in the Annual 
Species Reviews and strategic surveys, the taxa team joined with 
additional species experts to formalize the Survey and Manage Program 
objectives for Siskiyou Mountains salamander. In anticipation of the 
eventual removal of the Survey and Manage Program, they developed their 
management recommendations into a Conservation Strategy for Siskiyou 
Mountains Salamanders in the Northern Portion of the Range (Olson et 
al. 2007). The USFS and BLM committed to implement this Conservation 
Strategy in the August 16, 2007, Conservation Agreement for the 
Siskiyou Mountains Salamander (Plethodon stormi) in Jackson and 
Josephine Counties of southwest Oregon and in Siskiyou County of 
northern California (USDA and USDI 2007; USDI 2007b).
    In accordance with management objectives for Category D species, 
the Conservation Strategy relies on long-term management of a subset of 
known salamander sites. A panel of scientists and resource managers 
selected high-priority sites and considered a number of criteria 
including existing Federal Standards and Guidelines for the planning 
area, distribution and quality of habitat, known locations of 
salamanders, and potential risk factors such as fire hazard, road 
density, and land ownership. To ensure the existence of well-
distributed, interacting subpopulations, these criteria were evaluated 
at three spatial scales: The entire Applegate River watershed, 19 
smaller watersheds within the Applegate River watershed, and individual 
sites. Of 316 known salamander locations on Federal lands, 151 (48 
percent) were included in the 110 high-priority salamander management 
areas selected (some management areas encompassed multiple salamander 
sites). Of the 110 selected sites, 44 are on BLM lands and 66 are on 
the Rogue River-Siskiyou National Forest. Each high-priority 
salamander-management site is intended to maintain a subpopulation of 
Siskiyou Mountains salamanders over the long term (100 years). Because 
habitat-disturbing activities are regulated to varying degrees across 
the entire NWFP area occupied by the salamanders, the scientists who 
developed the strategy anticipate that many additional populations will 
continue to persist in reserved lands and in Matrix where habitat is 
retained for other reasons (Olson et al. 2007, p. 21).
    Each high-priority salamander-management site was evaluated for 
application of one of two management strategies. The first strategy 
focuses on maintaining habitat conditions for salamanders at the site 
by limiting activities that may have adverse effects on substrate, 
ground cover, forest condition, or microhabitat and microclimate. The 
second strategy allows for greater latitude in activities at the high-
priority site by applying the existing National Fire Plan Fire 
Management Recommendations to the high-priority site. This two-tiered 
approach attempts to integrate the fire ecology of the area, current 
forest conditions, fuel loads, and proximity to populated areas while 
providing for the persistence of Applegate salamander populations over 
the long term.
    The Conservation Strategy contains a rigorous risk assessment 
(Olson et al. 2007, p. 22 and Appendix 2), which concludes that 
implementation of the Strategy presents an extremely low risk to the 
species' persistence at the range-wide scale. This conclusion is based 
on evaluation of the comparative risk of losses of individuals or 
subpopulations due to fuels management activities versus higher risk of 
losses if high-intensity wildfires occur at untreated sites. Other 
risks posed by other forest management activities are ameliorated by 
the protection-buffer approach adopted from current Survey and Manage 
guidance. Redundancy of protected sites and a mix of protective and 
restoration approaches across the entire range of the Applegate 
salamander also act to increase the likelihood of persistence over the 
long term.
    The Conservation Strategy was authored by four of the most 
published scientific experts on this species (D. Olson, D. Clayton, H. 
Welsh, and R. Nauman, among others), and incorporates habitat modeling 
and risk assessment in the evaluation of species persistence and 
distribution within the strategy area. The Conservation Strategy also 
contains provisions to support monitoring and strategic surveys to 
address gaps in our knowledge of the species and its conservation. 
Funding for these efforts is anticipated to come from the USFS and 
BLM's Special Status Species programs. Implementation and effectiveness 
of this Conservation Strategy will be reviewed every five years by BLM, 
USFS, and the Service. Based on these regular reviews, or significant 
information that may become available between the five-year reviews, 
the Conservation Strategy may be revised to refine the plan or address 
emerging issues.
    In anticipation of the discontinuation of the Survey and Manage 
Program, biologists from the Klamath National Forest (KNF) and the 
Service's Yreka Fish and Wildlife Office (YFWO) are developing a 
Conservation Strategy to guide management of both Grider and Scott Bar 
salamander populations on lands administered by the KNF. This Strategy 
would apply to over 90 percent of the range of the Grider salamander 
DPS, and 78 percent of the Scott Bar salamander's range. The draft KNF 
Strategy does not require surveys to be conducted prior to ground-
disturbing activities; instead, all suitable salamander habitat (talus 
substrate) is assumed to be occupied and managed for long-term 
persistence of salamander populations. Similar to the Conservation 
Strategy for Applegate salamanders (Olson et al. 2007), the draft KNF 
Strategy balances protection of existing suitable habitat with active 
management of risks such as hazardous fuels. Small habitat patches 
(less than 5 ac (2 ha)) and locations with high likelihood of occupancy 
by salamanders (lower slopes, northerly exposures) receive strict 
protective guidelines; whereas habitat patches on upper slopes with 
southerly exposures may receive fuels reduction treatments that reduce 
canopy closure to a limited degree.
    As discussed below in Factor D, we are not relying on 
implementation of the Conservation Strategies in making our 
determination that listing the Siskiyou Mountains salamander and Scott 
Bar salamander is not warranted. We have included this discussion 
solely as background for the public and to acknowledge USFS and BLM 
efforts to

[[Page 4391]]

further reduce possible threats to the species.

Summary of Factors Affecting the Species

    Section 4 of the Act (16 U.S.C. 1533) and implementing regulations 
at 50 CFR part 424 set forth procedures for adding species to the 
Federal List of Endangered and Threatened Wildlife. In making this 
finding, we summarize below, information regarding the status and 
threats to this species in relation to the five factors in section 
4(a)(1) of the Act. In making our 12-month finding, we considered and 
evaluated all scientific and commercial information in our files, 
including information received during the public-comment period that 
ended May 29, 2007.

Siskiyou Mountains Salamander

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

    Like other plethodontids, Siskiyou Mountains salamanders require 
moisture for respiration (Nussbaum et al. 1983, pp. 73, and 90). This 
physiological requirement limits the time during which they are active 
at the soil's surface to relatively brief, rainy periods in the spring 
and fall (Nussbaum et al. 1983, pp. 102-103; Clayton et al. 1999, p. 
133). These salamanders engage in important behaviors, including 
foraging and breeding, during periods of surface activity (Feder 1983, 
p. 296). During the remainder of the year, they retreat into rocky 
substrates, which provide refuge from the climatic extremes of the 
eastern Klamath Mountains (Nussbaum et al. 1983, p. 102). Given their 
physiology and life histories, disturbances that reduce surface and 
soil moisture, relative humidity, or suitable rocky substrates may 
negatively affect these species. Disturbances that possibly impact 
Siskiyou Mountains salamanders include timber harvesting, fires, road 
construction, mining, and quarrying.

Effects of Timber Harvesting on Siskiyou Mountains Salamanders

    Timber harvesting may impact Siskiyou Mountains salamander by 
killing individuals or by reducing habitat quality. Ollivier et al. 
(2001, pp. 41-42) and Welsh et al. (2007a, p. 28) found that Siskiyou 
Mountains salamanders were associated with characteristics found in 
mature forests, such as dense canopy cover, large-diameter trees, and 
mossy ground cover. Other studies have shown that Siskiyou Mountains 
salamanders occur within a wide range of forest conditions, including 
in recently clear-cut sites and in open-canopy forest (e.g., Bull et 
al. 2006, p. 24; Farber et al. 2001, p. 13; Farber 2007, p. 3). The 
conclusions of these studies do not necessarily conflict since it is 
possible that these salamanders occur within a wide range of habitat 
conditions while selectively using or receiving greater fitness from a 
subset of them, or are more easily detected in a subset of them. 
Alternatively, these species may select habitat based on attributes 
that are not dependent on forest age or structural class. For example, 
they may select habitat with cool, moist microclimates, which are 
common in mature forests but also occur under other conditions (e.g., 
in deep drainages or on north-facing slopes). The paucity of rigorous 
scientific information about Siskiyou Mountains salamanders makes an 
accurate evaluation of their habitat associations (see Habitat 
Associations section above) and sensitivities to timber harvesting 
difficult. Information about the effects of timber harvesting on this 
species is currently limited to inferences based on the physiology of 
this species, two studies of the effects of timber harvesting on 
Siskiyou Mountains salamanders, and extrapolation of inferences from 
studies of the effects of timber harvesting on other species of 
plethodontid salamanders.
    Timber harvesting may negatively affect Siskiyou Mountains 
salamander by reducing soil moisture and increasing soil temperature. 
Studies by Chen et al. (1993, pp. 233-234; 1995, pp. 77-82; 1999, pp. 
292-294) in Pacific Northwest Douglas fir forests found that both soil 
and air were drier and warmer in clear cuts and clear-cut forest edges 
than in adjacent old-growth forest. These results indirectly suggest 
that clear-cutting may negatively affect these animals. We are not 
aware of any studies on the effects of other silvicultural techniques 
on forest microclimates. However, alternative even-age harvesting 
techniques (shelterwood and seed-tree cuts), uneven-age harvesting 
(single tree and group selection harvesting), and thinning retain more 
canopy cover than does clear-cutting and, therefore, probably have 
lower impacts on forest microclimates. The effects of timber harvesting 
also strongly depend on the silvicultural prescription (e.g., the 
volume of wood removed and the size, volume, and distribution of 
retained trees, snags, and logs) and on site-specific factors (e.g., 
climate and slope aspect). We expect that the effects of silviculture 
on Siskiyou Mountains salamander depend primarily on the intensity and 
scale of the disturbance.
    We are aware of two studies analyzing the effects of timber 
harvesting on Siskiyou Mountain salamanders. The first was conducted in 
Siskiyou County, California by the USFS (D. Clayton, cited in Bull et 
al. 2006, p. 21; Olson et al. 2007, p. 16). This study compared 
abundances of Siskiyou Mountains salamanders through time at a clear-
cut site and an adjacent selectively cut site. In the clear-cut site, 
the researchers found 40 salamanders (10 salamanders per person, per 
hour) the spring after the harvest, one juvenile the following year, no 
animals in the subsequent 7 years, and one juvenile during an 
opportunistic survey in the tenth year. In comparison, they 
consistently found 3 to 6 salamanders per person, per hour in the 
selectively cut site during the same years sampled (Bull et al. 2006, 
p. 21). The CDFG resurveyed the same clear-cut site in the spring and 
fall of the eleventh year post-harvest (Bull et al. 2006, p. 21). 
Single surveyors found 10.6 salamanders per person, per hour in the 
spring and 4.25 salamanders per person, per hour in the fall. This 
result suggests that, while Siskiyou Mountains salamanders may be 
negatively impacted by intensive timber management practices such as 
clear-cutting, they are able to recover in, or recolonize, some clear-
cuts as vegetation recovers. As importantly, less intensive harvest 
methods may have less impact on salamander abundance. However, 
inferences from both sets of surveys are highly limited because the 
surveys did not include pre-harvest data and were conducted in only one 
pair of plots.
    In a nearby area, Fruit Growers Supply Company monitored Siskiyou 
Mountains salamanders on the Elliot Fly Timber Harvesting Plan. They 
monitored salamanders on 39 plots (35 harvested and 4 controls). The 
harvesting method was a selective cut, and logs were removed by 
helicopter, a method which significantly reduces the amount of ground 
disturbance. Plots were surveyed prior to harvest, 1 year post-harvest, 
and 10 years post-harvest (Taylor 2007, p. 1). Estimates of relative 
abundance (count data) in the harvested plots ranged from 1.8 to 2.0 
captures per survey compared to 2.0 to 3.2 captures per survey in 
unharvested controls, and did not significantly change during the 
study. These results suggest that the harvest did not significantly 
adversely affect the salamanders (Taylor 2007, p. 3). The determination 
of no significant difference between treatments and control plots was 
likely influenced by the high variability observed within and

[[Page 4392]]

between plots. All Siskiyou Mountains salamander life stages were found 
in the harvested plots, likely indicating that these populations 
continued to reproduce following harvesting. Although this study used a 
more rigorous design and was larger than the nearby USFS paired-plot 
study, its inferences are also limited because pre-harvest data were 
only collected one year prior to harvest and the study plots were not 
randomly selected.
    All life-history stages of Siskiyou Mountains salamander, including 
gravid females (carrying eggs), have been found in open-canopy forest 
and recent clear-cuts (Farber et al. 2001, p. 13; Bull et al. 2006, p. 
24; Farber 2007, p. 3). However, little is known about relationships 
between forest conditions and the population dynamics of the Siskiyou 
Mountains salamander. Welsh et al. (2007b) analyzed relationships 
between forest age class and the age structure and body condition of 
both Siskiyou Mountains salamanders and Scott Bar salamanders. All 
salamander age classes were found in pre-canopy (0 to 33 years) sites, 
but 8 of 11 individuals detected in those sites were juveniles or 
subadults. If representative of population age structure, this 
observation could indicate that pre-canopy sites function as `sink' or 
dispersal habitat for non-reproductive individuals. Alternatively, high 
proportions of juveniles could indicate high reproductive rates and 
population recovery following logging. Sample sizes were too small to 
test these hypotheses. Welsh et al. (2007b) also found that Siskiyou 
Mountains salamanders in mature (100 to 199 years) sites had 
significantly higher median body condition (ratio of body mass to 
length) than those in young sites (31 to 99 years). This could indicate 
that young forest stands provide lower quality habitat than mature 
stands.
    Timber harvesting could also affect Siskiyou Mountains salamanders 
at spatial scales larger than individual salamander sites. The petition 
to list the Siskiyou Mountains salamander (Center for Biological 
Diversity et al. 2004, p. 8) asserts that timber harvesting creates 
gaps in the distribution of this species because it is rarely able to 
recolonize habitat after local populations are extirpated. Indirectly 
supporting this hypothesis, studies of the closely related Del Norte 
salamander showed that it is highly sedentary and, therefore, likely to 
have limited dispersal abilities. Welsh and Lind (1992, p. 427) 
reported that the longest movement by an individual Del Norte 
salamander was 119 ft (36.2 m) over 6 months, and Lowe (2001, p. 27) 
found that the longest movement was 129.9 ft (39.6 m) over 2 years. 
Average movements were substantially smaller than these: 22 ft (6.7 m) 
over 2 years (Lowe 2001, p. 27) and 16.7 ft (5.1 m) over 6 months 
(Karraker and Welsh 2006, p. 136). Siskiyou Mountains salamanders, and 
in particular Scott Bar salamanders, have relatively longer limbs than 
Del Norte salamanders and may be capable of longer movements, but their 
dispersal abilities are still likely limited. Some researchers have 
suggested that dispersing juvenile Siskiyou Mountains salamanders 
readily colonize logged sites (Welsh 2005, pp. 1-2) and road cutbanks 
(Nussbaum 1974, p. 13). Alternatively, it is possible that salamanders 
in regenerating logged sites and road cutbanks are indicative of 
population persistence and recovery following disturbance, rather than 
extirpation and subsequent recolonization.
    Welsh and Ollivier (1995, pp. 8-9) suggested that tractor yarding 
of logs during timber harvesting may impact Siskiyou Mountains 
salamanders by compacting, breaking, or realigning talus. If tractor 
yarding has these effects, it could reduce the interstitial spaces in 
talus and thereby reduce habitat quality for these species. Although it 
is reasonable to conclude that tractor yarding may disturb talus 
substrates, research has not demonstrated how this affects salamander 
populations.
    In summary, rigorous research of the effects of timber harvesting 
on Siskiyou Mountains salamanders is needed, but intensive timber 
harvesting practices, such as clear-cutting and tractor yarding, appear 
to have negative short-term (30 years or less) effects on abundance, 
population structure, and body condition of these species (Welsh et al. 
2007b). Intensive timber harvesting likely affects these salamanders by 
changing forest characteristics that influence microclimates for them, 
for example, by opening the forest overstory and understory canopies 
and reducing coverage of down wood and leaf litter. Despite these 
effects, it is also clear that the salamanders frequently persist in 
intensively harvested habitats, and there is no information suggesting 
that populations are permanently extirpated by timber harvest. It is 
unknown whether these salamanders may be temporarily extirpated from 
severely disturbed sites or simply retreat underground during the 
initial period of post-disturbance recovery. Alternative silvicultural 
techniques, such as thinning, selective harvesting, and helicopter 
yarding, appear to be less harmful to these salamanders than more 
intensive harvesting methods.

Timber Harvesting Effects on Other Plethodontids

    To support their assertion that the Siskiyou Mountains salamander 
is threatened by timber harvesting, the petitioners cite studies of 
other closely related species. Most studies of the closely related Del 
Norte salamander indicate that this salamander is more abundant in 
mature forest than in other forest age classes (Raphael 1988, p. 27; 
Welsh and Lind 1991, p. 400; Welsh and Lind 1995, p. 208). In contrast, 
Diller and Wallace (1994, p. 316) did not detect a relationship between 
forest age and the presence of Del Norte salamanders near the northern 
California coast. It is possible that forest structural characteristics 
(e.g., canopy cover) more strongly influence microclimates for 
salamanders in the interior of the Klamath Mountains than near the 
coast, where temperatures are more moderate and moisture is less 
limiting.
    Karraker and Welsh (2006, p. 137) found lower abundances of Del 
Norte salamanders in clear-cuts than in mature stands. All salamander 
life stages were observed in clear-cuts, indicating that reproduction 
was occurring in them. Abundances were similar in commercially thinned 
and mature stands. Welsh et al. (2007b) found significant positive 
relationships between forest age class and presence and abundance of 
Del Norte salamanders. Adult salamanders accounted for a larger 
proportion of individuals observed in old-growth (older than 200 years) 
and mature (100 to 199 years) stands than they did in young (31 to 99 
years) stands. The authors suggested that higher proportions of adult 
salamanders are indicative of greater population stability for this 
species. In contrast, salamanders at pre-canopy (0 to 33 years), young, 
and old-growth sites had higher median body condition than those in 
mature stands or the reference site (thought to be a high-quality 
site). The authors speculated that the apparent inconsistencies in 
their results were related to greater competition and poorer body 
condition in sites with higher salamander abundances, but more research 
is needed to test this hypothesis. Biek et al. (2002, p. 137) found 
similar abundances of Del Norte salamanders in clear-cuts and mature 
forests in Oregon, apparently contradicting the results of the studies 
discussed above.
    Evaluation of studies of the effects of timber harvesting on 
plethodontids outside the Plethodon elongatus Complex may improve our

[[Page 4393]]

understanding of the effects of harvesting on Siskiyou Mountains 
salamanders. However, these studies should be cautiously considered due 
to differences in the natural histories of these species. Most 
plethodontids occupy soil, surface litter, and woody debris in mesic 
environments (e.g., where it frequently rains during summer), whereas 
Siskiyou Mountains salamanders occupy talus substrates, which provide 
refuge from the temperature extremes and dry conditions that 
characterize the eastern Klamath Mountains.
    Grialou et al. (2000, pp. 108-110) found that western red-backed 
salamanders in mesic forests in southwestern Washington occupied recent 
clear-cuts (2 to 4 years post-harvest) but at significantly lower 
abundances than in adjacent older stands. Body sizes of salamanders 
(subadults and juveniles) were smaller the year after harvesting but 
were normal by the second year. Gravid females were captured on clear-
cut plots before and after harvest. Grialou et al. (2000, p. 111) 
suggested that reduced abundances of western red-backed salamanders in 
clear-cuts were related to soil compaction, loss of woody debris, and 
decreased leaf litter cover associated with harvesting. Bury and Corn 
(1988, p. 171) reported plethodontid salamanders to be absent in four 
clear-cut study sites, but their results were equivocal because 
detection rates were very low in all of the habitats studied. In 
contrast to the above studies, Corn and Bury (1991, p. 311) found that 
abundances of western red-backed salamanders were not significantly 
different in recent clear-cuts (less than 10 years old) and old-growth 
forest.
    Studies of plethodontids in the mid-western and eastern United 
States (Ash 1997, p. 985; deMaynadier and Hunter 1998, pp. 344-345; 
Herbeck and Larsen 1999, p. 626) and western Canada (Dupuis et al. 
1995, p. 648) indicated that clear-cutting can have significant short-
term impacts on plethodontid salamander abundance. Dupuis et al. (1995, 
p. 648), Ash (1997, p. 987), and Herbeck and Larsen (1999, p. 626) 
reported that plethodontid salamanders were frequently absent from 2- 
to 5-year-old clear-cut stands. However, the impact of clear-cutting on 
these salamanders may be temporary, as one study (Ash 1997, pp. 985-
986) showed that salamanders returned to clear-cut areas 4 to 6 years 
after cutting, and their return was followed by rapid increases in 
their numbers. Statistical modeling of salamander abundances on clear-
cut plots indicated that salamanders would equal or exceed numbers on 
forested plots by 20 to 24 years after cutting (Ash 1997, pp. 985-986). 
Knapp et al. (2003, pp. 754-758) used a randomized, replicated design 
to quantify plethodontid salamander populations on harvested 
timberlands of the Appalachian Mountains in Virginia and West Virginia. 
While salamander abundances were lower in clear-cuts than in control 
plots, there were no differences in the proportion of gravid females or 
in the average number of eggs in gravid females. Moreover, there were 
no differences in the proportion of juvenile animals, except in one 
plethodontid species, which had a higher proportion of juveniles in 
uncut treatments.

Extent of Timber Harvesting Within the Range of the Siskiyou Mountains 
Salamander

    Evaluation of the threat potentially posed by modification or loss 
of habitat via timber harvest must be based on an assessment of the 
biological mechanisms involved, as well as quantification of the 
likelihood of those mechanisms occurring to an extent and magnitude 
reasonably expected to result in the threat of extinction. The extent 
and magnitude of potential effects caused by timber harvest are 
strongly influenced by existing land management regulations on the 
majority of the species' ranges. Approximately 85 percent of the range 
of the Siskiyou Mountains salamander occurs on Federal lands managed 
under the NWFP (USDA and USDI 1994) (see Table 3 above). In general the 
system of reserves and management guidelines provided by the NWFP 
provide a substantial reduction in the likelihood of widespread habitat 
alteration due to timber harvesting.
    The rate and extent of timber harvest has declined dramatically on 
Federal lands within the NWFP area during the past 30 years (USDA and 
USDI 2005), particularly on the Klamath National Forest, which 
comprises roughly 91 percent of the range of the Grider salamander. 
These reductions have been primarily due to the implementation of the 
NWFP and other Federal land management regulations. During the 6-year 
period from 2000 to 2005, the Klamath National Forest sold and removed 
an average of 15.9 million board feet of timber annually, compared with 
187.8 million board feet per year during 1985 to 1990 (inclusive), and 
238.2 million board feet per year from 1979 to 1984; this marks a 
reduction of roughly 93 percent from the 1979 to 1984 period (USDA 
2006a). Perhaps more importantly, the amount of intensive timber 
management (regeneration harvests, overstory removal) has declined 
sharply, from an average of 3,733 ac per year from 1988 to 1991, to 38 
ac per year from 2000 to 2006. Intensive harvest prescriptions such as 
clear-cutting were not used in 2001 or 2002, nor in 2004 to 2006 (USDA 
2007b). Likewise, timber harvest on the Rogue River National Forest 
(which comprises roughly 66 percent of the range of the Applegate 
Population of the Siskiyou Mountains salamander (Clayton 2007b) 
declined by 96 percent during the last 30 years. Annual timber harvest 
during the 1980s averaged 182 million board feet, compared with 8 
million board feet per year from 2000 to 2006 (USDA 2007c). Since 1996, 
only one timber sale has been sold and harvested on the Rogue River 
National Forest's Applegate Ranger District. Timber harvest, 
particularly intensive harvest methods, has also declined dramatically 
on lands administered by the BLM within the range of Applegate 
salamander. Mean annual harvest on the BLM's Ashland Resource Area have 
declined from 2,240 ac (907 ha) per year between 1995 and 2000, to 664 
ac (269 ha) per year between 2001 and 2007 (USDI 2007a). Less than 270 
ac (109 ha) per year have been harvested since 2003 (USDI 2007a). 
Intensive harvest methods, such as clear-cuts and shelterwood harvests, 
have declined from 54 percent of acres harvested in the mid-1990s, to 
less than 1 percent of the annual harvest since 2001. The 
implementation of the NWFP and subsequent declines in timber harvest 
levels on Federal lands, particularly intensive harvests thought to 
potentially affect salamanders, greatly reduces the likelihood that a 
substantial proportion of the salamanders' populations will be affected 
by logging. We anticipate that reduced levels of timber harvest will 
continue into the foreseeable future because this has been the trend 
for the last 30 years and we have no substantial information that 
indicates that this trend will be reversed in the foreseeable future. 
In addition, the essential goals of the NWFP remain in effect and we 
have no information that would lead us to anticipate changes to the 
overall goals of this ecosystem management strategy. The removal of the 
Survey and Manage guidelines is relevant only to occupied salamander 
sites that overlap with Federal forest management projects; this 
comprises a very small fraction of the NWFP area and will have an 
insignificant effect on the overall levels of timber harvest within the 
range of the Siskiyou Mountains salamander.

[[Page 4394]]

    Intensive timber harvest methods such as clear-cutting are 
extremely limited in extent on Federal lands within the ranges of these 
salamanders, but where they occur they may reasonably be expected to 
have negative impacts on salamander populations. The available evidence 
does not demonstrate that the less-intensive harvest methods commonly 
employed on Federal lands have had substantial impacts to salamander 
populations, and we do not anticipate such impacts in the future. 
However, we acknowledge that the relationship between degree of 
management intensity and effects to salamanders requires further 
investigation.
    Intensive timber harvesting practices on private timberlands affect 
only 10 percent of the Siskiyou Mountains salamander's range. The 
majority of private lands within the salamander's range occur as small 
parcels (typically one square mile or less) in a checkerboard pattern 
surrounded by Federal lands. Salamander populations on private lands 
may be negatively affected by timber harvesting but are dispersed among 
populations on Federal lands where management is more favorable. This 
acts to maintain redundancy, distribution, and connectivity among 
Siskiyou Mountains salamander populations within the mix of Federal and 
private lands. In addition, surveys and monitoring of Siskiyou 
Mountains salamanders on private timberlands demonstrate that numerous 
populations of Siskiyou Mountains salamanders continue to exist post-
harvest and some exhibit evidence of normal population structure 
(Farber et al. 2001, p. 13; Bull et al. 2006, p. 24; Farber 2007, p. 
3), indicating that extirpation of salamander populations on harvested 
private timberlands is not a substantial threat to the species.

Wildfire

    Wildfire is thought to be a potential threat to Siskiyou Mountains 
salamander habitat (Olson et al. 2007, pp. 15, 25-26). Fire suppression 
and logging have altered forest structure and increased fuel loading in 
much of the Klamath-Siskiyou region (Skinner et al. 2006, pp. 178-179). 
Fire regimes within the ranges of the species have largely shifted from 
frequent, low-to-moderate or mixed-severity fires to less frequent, 
more severe fires (Agee 1993, pp. 388-389; Taylor and Skinner 1998, p. 
298; USDA 1999, pp. 2-76 and 2-82; Skinner et al. 2006, p. 191). 
However, debate exists concerning the extent to which this effect is 
operating in the Klamath and Siskiyou Mountains (Odion et al. 2004, pp. 
933-934). Climate changes associated with global warming are expected 
to increase the frequency of large, severe fires in this region (see 
Factor E discussion below). However, fire modeling suggests that the 
level of tree mortality would be highly variable within the geographic 
ranges of these species (USDA 1999, pp. 2-76 and 2-82; Suzuki and Olson 
2007, p. 8), resulting in a mosaic pattern of habitat effects. Similar 
mosaics of effects have been documented for large fires in other 
regions (e.g., Eberhart and Woodard 1987, pp. 1207-1212). In addition, 
the talus outcrops inhabited by these salamanders may modify the 
behavior of fire (e.g., Major 2005, p. 95) by acting as minor fuel 
breaks and influencing the mosaic of burned and unburned areas.
    The direct effects of fire on these species are unknown but 
interstitial spaces in deeper talus habitat likely provide underground 
refugia for these salamanders during fires (DeGross and Bury 2007, p. 
7). In addition, wildfires typically burn during the dry summer and 
fall months when the salamanders are not on the surface; the period of 
surface activity coincides with wet climatic conditions prohibitive to 
wildfire.
    The indirect effects of fire on these species are also unknown. 
Severe wildfires, by definition, remove or significantly reduce canopy 
cover; consume moss, duff, and forest litter; and may sterilize surface 
soil layers. Siskiyou Mountains salamanders occasionally use woody 
debris as cover during surface activity, and canopy and leaf litter 
cover may influence habitat quality for them (see Habitat Associations 
section), so these habitat changes likely affect salamanders during 
some period of post-fire recovery.
    We are unaware of any studies of the effects of prescribed burning 
on Siskiyou Mountains salamanders. Prescribed fires are usually applied 
in the spring or fall, when moisture levels minimize the risk of damage 
to mature trees and unacceptable spreading of fire. Moisture levels 
during periods of surface activity by these species are higher than 
those that are appropriate for prescribed burning, so the risk of 
direct mortality during prescribed fires is likely low. Prescribed 
fires could temporarily reduce the quality of habitat for these species 
by consuming understory vegetation, down wood, litter, and duff. 
Conversely, the benefits of prescribed fires may outweigh their costs 
to salamanders in some areas by reducing the risk of severe wildfires.

Roads and Road Construction

    Research suggests that forest roads may significantly restrict 
movements and local abundances of plethodontid salamanders (deMaynadier 
and Hunter 2000, pp. 63-64; Marsh et al. 2005, p. 2006; Semlitsch et 
al. 2007, p. 159). Forest roads may reduce dispersal by salamanders, 
leading to lower gene flow and reduced long-term persistence of 
populations (Marsh et al. 2005, p. 2007). Conversely, Nussbaum (1974, 
p. 13) found numerous salamander locations within road cuts, and 
suggested that the road construction provided habitat in the form of 
newly exposed fissured rock, or at least did not render the adjacent 
habitat unsuitable. Within the ranges of the Siskiyou Mountains 
salamander, roads are typically constructed for access to timber 
harvest operations. While road densities are high in some areas within 
the ranges of the salamanders (USDA 1999, pp. 2-31), the amount of road 
construction activity has declined sharply as timber harvest levels 
have dropped. Road decommissioning projects may have short-term 
localized effects to rock substrates, but are designed to re-create a 
natural substrate. The small area affected by road construction and the 
linear nature of habitat impacts, combined with the ability of 
salamander populations to occupy road cuts, suggest that forest roads 
do not pose a significant threat to populations of Siskiyou Mountains 
salamanders (Olson et al. 2007, p. 17). We are not aware of any other 
information that suggests that the presence of roads or road 
construction presents a substantial threat to the Siskiyou Mountains 
salamander.

Mining and Rock Quarrying

    Some sites occupied by the Siskiyou Mountains salamander have 
evidence of previous mining activity. It is unclear whether or how 
salamanders in those sites may have been affected by these activities. 
Rock quarrying could pose a greater threat to individual populations 
because of the potentially greater intensity of the disturbance. 
However, this activity occurs within an extremely small proportion of 
this species' range, and is unlikely to have more than localized 
effects (Olson et al. 2007, p. 17). We are not aware of any information 
that suggests that mining or rock quarrying presents a substantial 
threat to the Siskiyou Mountains salamander.

Summary of Factor A

    While intensive timber management practices such as clear-cutting 
appear to

[[Page 4395]]

have negative impacts on the abundance of Siskiyou Mountains 
salamanders, this practice is severely restricted on Federal lands that 
constitute the vast majority of the species' range. Less intensive 
harvest practices appear to have relatively minor or short-term impacts 
to salamander abundance, and the available evidence suggests that 
salamander populations persist in a broad range of forest habitat 
conditions and under different management practices.
    Current management on Federal lands under the provisions of the 
NWFP protects salamanders via a system of reserves and land management 
guidelines (see Background Information: Land Management) that 
dramatically reduce the likelihood of large-scale reduction of suitable 
or occupied habitat. Until recently, the Survey and Manage guidelines 
also served to protect occupied salamander sites from disturbance from 
management activities. In the northern portion of the range, a 
Conservation Strategy has been implemented that will essentially 
continue the Survey and Manage Protections for Applegate salamander. 
However, even without Survey and Manage or Conservation Strategy 
protections, the available evidence does not show that timber harvest 
practices on Federal lands, either alone or in combination with other 
habitat disturbing activities such as mining, road building or 
wildfire, have substantially reduced the habitat or range of this 
species or are likely to do so in the foreseeable future.
    Intensive timber harvesting practices, such as clear-cutting and 
shelterwood removal, are more likely to occur on private timberlands. 
While it is reasonable to assume that abundance and population 
structure of Siskiyou Mountains salamander populations on private 
timberlands may be negatively affected by timber harvesting and other 
habitat disturbances, these lands constitute less than 10 percent of 
the species' range. Other factors combine to greatly reduce the 
likelihood that Siskiyou Mountains salamander populations will be 
threatened by management activities on private lands: (1) The majority 
of private lands within the species' range occur as small parcels 
(typically one square mile or less) in a checkerboard pattern 
surrounded by Federal lands; and (2) many salamander populations have 
persisted on private timberlands in spite of a history of timber 
harvest. We, therefore, conclude that timber harvesting and other 
management practices on private lands do not constitute a substantial 
threat to the Siskiyou Mountains salamander.
    Wildfires are expected to occur and may reduce habitat quality for 
some salamander populations; however, the effects of wildfires on 
salamander habitat are temporary and populations appear to recover as 
vegetation recovers. Wildfires typically burn in a mosaic pattern of 
intensities, leaving a variety of habitat conditions for salamanders 
within burned areas.
    In summary:
    (1) There is no evidence that the range of the Siskiyou Mountains 
salamander has changed from its historical size.
    (2) Despite over a century of mining, road building, and intensive 
timber harvest, salamander populations remain well-distributed in a 
wide variety of habitat conditions.
    (3) Results of field studies and surveys indicate that salamander 
populations recover following intensive habitat disturbances.
    (4) On Federal lands, which constitute the majority of this 
species' range, NWFP land allocations and Standards and Guidelines 
(excepting the Survey and Manage program) and other regulations 
contained in Land and Resource Management Plans provide a broad range 
of protections for salamander habitat.
    (5) The rate and intensity of timber harvest has declined 
dramatically on Federal lands and there is no reliable information 
suggesting that harvest rates or intensity will increase substantially 
in the foreseeable future.
    (6) While more intense harvesting may occur on private lands, these 
lands are patchily distributed among Federal land holdings and taken 
together constitute less than 10 percent of the species' range.
    (7) Available evidence does not indicate that other potential 
habitat threats to salamanders, individually or in combination with 
timber harvest (i.e., wildfire, mining and rock quarrying, and road 
building) have resulted in, or are likely in the foreseeable future to 
result in, significant habitat loss that would pose a threat to 
salamanders.
    Therefore, we conclude that the Siskiyou Mountains salamander is 
not now or in the foreseeable future, threatened by destruction, 
modification, or curtailment of its habitat or range.

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

    We are not aware of any information that indicates overutilization 
for commercial, recreational, scientific, or educational purposes 
threatens now, or in the foreseeable future, the Siskiyou Mountains 
salamander across its range.

Factor C: Disease or Predation

    Chytridiomycosis is a relatively recently described epidermal 
infection of amphibians caused by the chytrid fungus Batrachochytrium 
dendrobatidis. Chytridiomycosis has been implicated in mass 
mortalities, population declines, and extinctions of some amphibian 
species, but species appear to vary in their susceptibility to the 
disease (Daszak et al. 1999; Blaustein et al. 2005; Ouellet et al. 
2005; Pearl et al. 2007). This disease is most likely transmitted to 
amphibians by contact with infected water or other amphibians (Johnson 
and Speare 2003, p. 922). Batrachochytrium dendrobatidis requires 
moisture for survival (Johnson and Speare 2003, p. 922) and is 
therefore more likely to pose a threat to aquatic amphibians than to 
terrestrial ones. However, a chytrid infection was recently found in a 
terrestrial salamander, the Jemez Mountains salamander (Plethodon 
neomexicanus), living in a wet meadow (Cummer et al. 2005, p. 248). 
Infected aquatic amphibians appeared to be the most likely source of 
transmission of the disease to this individual. Bullfrogs (Rana 
catesbeiana) infected with B. dendrobatidis were recently found in a 
pond in Trinity County, California (Bettaso and Rachwicz 2006, p. 162), 
so it is possible that the disease occurs, or will soon occur, within 
the range of the Siskiyou Mountains salamander. Nonetheless, we do not 
anticipate that the Siskiyou Mountains salamander will be exposed to 
this disease or that exposure would lead to transmission through a 
significant portion of its range. This species is not associated with 
bodies of water, occurs in a characteristically dry environment, is 
only active above ground for brief and intermittent periods during the 
year, and appears to have limited dispersal abilities. Given these 
restrictions, we believe that the Siskiyou Mountains salamander is 
unlikely to be exposed to diseased water or infected aquatic amphibians 
and, if infected, is unlikely to transmit the disease between 
populations.
    The Service is not aware of any predators that potentially pose a 
threat to the species.
    Therefore, we find disease or predation does not threaten now, or 
in the foreseeable future, the Siskiyou Mountains salamander across its 
range.

Factor D: Inadequacy of Existing Regulatory Mechanisms

    To the extent that we identify possibly significant threats in the 
other factors, we consider under this factor

[[Page 4396]]

whether those threats are adequately addressed by existing regulatory 
mechanisms. Thus, if a threat is minor, listing may not be warranted 
even if existing regulatory mechanisms provide little or no protection 
to counter the threat.
    As described above in the ``Background: Land Management'' section, 
habitats occupied by Siskiyou Mountains salamanders receive protection 
from a number of sources such as the NWFP and other Federal land 
management regulations. Until recently, protections for the Siskiyou 
Mountains salamander on Federal lands included the Survey and Manage 
Mitigation Measure Standards and Guidelines portion of the NWFP. On 
private lands in California, the species complex receives protection 
pursuant to the California Endangered Species Act (CESA). The future of 
some of these regulations (Survey and Manage Program and State 
Protections) is in flux.

Federal Lands

Survey and Manage Mitigation Measure Standards and Guidelines

    Siskiyou Mountains salamanders and their habitat have received an 
additional layer of security from the Survey and Manage Mitigation 
Measure Standards and Guidelines (Survey and Manage Program) under the 
NWFP (USDA and USDI 1994). The Survey and Manage Program provided 
specific guidance for management of both genetic subunits of the 
Siskiyou Mountains salamander. Management guidance for Applegate 
salamander populations included identification of high-priority sites 
that will be managed to provide a reasonable assurance of long-term 
species persistence. In the southern portion of the range (Grider and 
Scott Bar salamanders), protections included the requirement of surveys 
prior to land management activities, and restrictions of habitat-
altering activities such as timber harvesting at occupied sites (see 
``Background: Land Management''). The USFS and BLM decided to remove 
the Survey and Manage Program from the NWFP, and published their ROD 
entitled ``To Remove or Modify the Survey and Manage Mitigation 
Measures Standards and Guidelines in Forest Service and Bureau of Land 
Management Planning Documents Within the Range of the Northern Spotted 
Owl'' in March 2004 (March 2004 ROD). The FSEIS for the March 2004 ROD 
identified potential mitigation measures, including sensitive species 
programs, for species affected by the removal of the Survey and Manage 
Program.
    In January 2006, the court in Northwest Ecosystem Alliance v. Rey, 
2006 U.S. Dist. Lexis 1846 (N.D. Wash.) ordered the March 2004 ROD set 
aside for failure to comply with the National Environmental Policy Act. 
With this order, the court reinstated the 2001 Survey and Manage ROD, 
which had modified the original Survey and Manage Program but 
maintained protections for the salamanders. At the end of July 2007, 
the USFS and BLM issued a new ROD (2007 ROD) to remove the Survey and 
Manage Mitigation Measure Standards and Guidelines portion of the 
Northwest Forest Plan. Following issuance of the 2007 ROD, the USFS and 
BLM petitioned the court to lift or modify the injunction against 
projects that relied on the 2004 ROD. In its November 21, 2007, order, 
the court denied the agencies' request (Conservation Northwest v. Mark 
E. Rey 2007 U. S. Dist. Lexis 88541 (N. D. Wash.)), but did not rule on 
the sufficiency of the 2007 ROD.
    With issuance of the 2007 ROD, the Survey and Manage Program has 
been eliminated for new project planning and decisions. However, 
because of the lag time in implementation of the 2007 ROD, most new 
Federal land management decisions issued in 2008 will be compliant with 
the former Survey and Management guidance for the Siskiyou Mountains 
salamander (West 2007); implementation of new projects compliant with 
the 2007 ROD is unlikely until 2009. Although judicial challenge to the 
removal of the Survey and Manage Program in the 2007 ROD is very 
likely, we assume for purposes of this finding that the Survey and 
Manage Program will not remain in effect in the future.
    Assuming the removal of the Survey and Manage Program, management 
of this species will be based on the USFS's Special Status Species 
Program and the BLM's Sensitive Species Program (Hughes 2007). The 
Special Status Species and Sensitive Species programs are anticipated 
to provide less stringent protections than those in the Survey and 
Manage Program; however, they include provisions for development of 
conservation strategies and Conservation Agreements, which, as 
discussed previously under ``Land Management,'' has already occurred 
with regard to the Applegate salamander, and is under development for 
the Grider salamander and Scott Bar salamander.
    It is important to note that, while the Service recognizes the 
added layer of security provided by Survey and Manage Protections for 
the Siskiyou Mountains salamander, our evaluation of the potential 
threats to this species does not indicate that the Survey and Manage 
Protections are key to the species' persistence. The petitioners cite 
statements in the 2004 FSEIS (USDA and USDI 2004) indicating that loss 
of the Survey and Manage Protections could result in gaps in the 
distribution of Siskiyou Mountains salamander. In addition, the Species 
Review Panel (USDA and USDI 2001, p. 16) concluded that ``[i]t is 
likely that non-protected land allocations will be required in order to 
ensure persistence for the species, both in the northern and southern 
portions of the range'' indicating that current reserves may be 
inadequate. We have carefully evaluated this information, and we find 
that these conclusions are no longer consistent with the current 
scientific knowledge about the Siskiyou Mountains salamander and Scott 
Bar salamander, because: (1) The conclusions were made based on a much 
smaller number of known populations (161) than what is known today 
(631); (2) they are based on a single unpublished habitat-associations 
study by Ollivier et al. (2001); and (3) they assumed extirpation of 
populations that experience any degree of timber harvesting. As 
described previously under ``Summary of Factors Affecting the Species: 
Factor A,'' the best available evidence indicates that Siskiyou 
salamanders persist in areas affected by timber harvest, and in 
particular, in areas subject to the less intensive harvesting methods 
employed on the vast majority of Federal lands that make up the species 
range and there is little evidence to support the speculation that the 
rate and intensity of timber harvest on Federal lands will increase in 
the foreseeable future, with or without the Survey and Manage 
protections.

Conservation Strategies

Conservation Strategy for the Siskiyou Mountains Salamander--Northern 
Portion of the Range

    As discussed in detail above under the Species Information: Land 
Management section, in anticipation of the eventual removal of the 
Survey and Manage Program, a team of researchers and biologists from 
USFS Pacific Northwest Research Station and the Service formalized the 
existing Survey and Manage Category D objectives for the Siskiyou 
Mountains salamander in the northern portion of its range (Applegate 
salamander) in a Conservation Strategy (Olson et al.

[[Page 4397]]

2007). The USFS and BLM committed to implement this Conservation 
Strategy in the August 16, 2007, Conservation Agreement for the 
Siskiyou Mountains Salamander (Plethodon stormi) in Jackson and 
Josephine Counties of southwest Oregon and in Siskiyou County of 
northern California (USDA and USDI 2007; Olson et al. 2007). However, 
because of the limited nature of the threats addressed by the 
conservation Strategy, we did not rely on it in determining whether 
listing the Siskiyou Mountains salamander is warranted.
    The petitioners (Greenwald and Curry 2007, p. 9) questioned whether 
the BLM will adhere to the Conservation Agreement because it is not 
incorporated into the proposed Western Oregon Plan Revision (WOPR) 
Draft Environmental Impact Statement (DEIS), a proposal to modify the 
NWFP land allocations and standards and guidelines on BLM lands in 
Oregon, which could potentially increase timber harvest levels on BLM 
lands within the range of the salamanders. Because we did not rely on 
the Conservation Strategy in reaching our determination, the 
petitioners' concern is not relevant. In any case, the timing of 
development and release of the WOPR DEIS precluded inclusion of the 
then-unsigned Conservation Agreement; the BLM has subsequently provided 
a letter to the Service clarifying the BLM's commitment to implement 
the Conservation Strategy regardless of the eventual outcome of the 
WOPR proposal (USDI 2007b).
    The petitioners also question the ability of the Conservation 
Agreement to conserve the Siskiyou Mountains salamander because it 
protects only roughly half of the currently known salamander locations 
and allows management of fire risk at 48 locations (Greenwald and Curry 
2007, pp. 10-11). Petitioners apparently assume that only the selected 
high-priority sites will receive any degree of protection, management 
guidelines designed to reduce fire risk at 48 sites will harm 
populations, and significant losses of Applegate salamander populations 
not specifically protected by the strategy are likely. Although we did 
not rely on the Conservation Strategy in reaching our conclusion, we 
note that the available information does not support these assumptions. 
It is unlikely that a high proportion of the non-network sites are at 
risk because of other protections in place. For example, many of the 
289 Siskiyou Mountain salamander locations not selected for the 
population network fall within NWFP reserves and other areas not likely 
to experience intensive disturbance, and, as described above under 
Factor A, there is little evidence to suggest that substantial losses 
of populations will occur as a result of foreseeable forest management 
activities. The Conservation Strategy was authored by four of the most-
published scientific experts on this species (D. Olson, D. Clayton, H. 
Welsh, and R. Nauman, among others), and incorporates habitat modeling 
and risk assessment in the evaluation of species persistence and 
distribution within the strategy area. The petitioners present no 
information or analysis to support their contention that the expert 
team somehow erred in the development of the Conservation Strategy.
    The petitioners assert that the Conservation Strategy is unlikely 
to be effective because it contains management recommendations that 
appear to lack regulatory force (Greenwald and Curry 2007, p. 10) and 
further claim that the Conservation Strategy does not meet the 
standards of the Service's Policy for Evaluating Conservation Efforts 
(PECE) (68 FR 15100; March 28, 2003) (Greenwald and Curry 2007, p. 11). 
In response to the petitioners' first concern, we have no basis to 
conclude that the Federal parties to the Conservation Agreement will 
fail to comply with their own management guidance, and note that the 
Service will be a participant in the 5-year reviews described in the 
Strategy under Adaptive Management (Olson et al. 2007, p. 39-40). As 
described under ``Background: Land Management,'' the Conservation 
Strategy for the Siskiyou Mountains Salamander, Northern Portion of the 
Range is simply the formalization of existing Survey and Manage 
guidance for northern populations of Siskiyou Mountains salamanders; 
guidance deemed adequate by the petitioners (Center for Biological 
Diversity et al. 2003, p. 17) and the Survey and Manage taxa team 
experts.
    In response to petitioners' reliance on PECE, we emphasize that 
application of the PECE is inappropriate here. The Service may rely on 
conservation efforts that meet the standards of PECE in making listing 
determinations. In other words, a conservation effort relied on 
consistent with PECE can be dispositive as to the Service's ultimate 
finding on the status of a species. The policy therefore requires a 
high level of certainty that conservation efforts will be implemented 
and will be effective to ameliorate threats that would otherwise 
warrant listing of a species. Even in the absence of the Conservation 
Strategy, we do not consider the threats to the Siskiyou Mountains 
salamander under factors A through E of Section 4(a)(1) of the Act, now 
or in the foreseeable future, substantial enough to warrant its listing 
under the Act. Therefore, although implementation of the Conservation 
Strategy may be beneficial for the Siskiyou salamander, we did not rely 
on it in making our determination that the species does not warrant 
listing.

Western Oregon Plan Revisions

    The WOPR are a proposal by the BLM to revise six resource 
management plans (RMPs) that cover all BLM-administered lands in 
western Oregon. In August 2003, the American Forest Resource Council, 
the Association of Oregon and California Counties, and the Secretaries 
of Interior and Agriculture entered into a settlement agreement 
requiring the BLM to revise its RMPs to meet the mandated requirements 
of the Oregon and California Railroad and Coos Bay Wagon Road Grant 
Lands Act of 1937. In accordance with this agreement, the BLM is 
proposing to revise existing RMPs to replace the NWFP land-use 
allocations and management direction. In its August 16, 2007, DEIS for 
the Revision of the Western Oregon RMPs, the BLM describes three action 
alternatives designed to meet the purpose and need of the plan 
revisions, and a no-action alternative. Each of the action alternatives 
includes a range of management strategies; however, none of the action 
alternatives propose to retain NWFP late-successional reserves, and all 
action alternatives would result in a reduction in riparian reserve 
areas.
    While these proposed revisions have the potential to increase 
timber harvesting within the range of the Siskiyou Mountains 
salamander, we cannot at this time predict which alternative, including 
the no action alternative, will be selected or evaluate the potential 
effects to the 11 percent of the range of the Siskiyou Mountains 
salamander that occurs on lands administered by BLM in Oregon.
    While the potential effects of possible RMP changes on the small 
percentage of Siskiyou Mountains salamander's range that occurs on BLM 
lands are unknown, NWFP land-use allocations and management direction 
provides substantial protection for the Siskiyou Mountains salamander 
and its habitat. If existing Federal management for the Siskiyou 
Mountains salamander is modified in the future, the Service can 
consider any such changes in the context of the degree and immediacy of 
potential threats to the Siskiyou Mountains salamander at that time.

[[Page 4398]]

State Regulations

    In California, the Siskiyou Mountains salamander is listed as a 
threatened species and receives substantial protection pursuant to 
CESA. On private timberlands, this protection includes a requirement 
for pre-project surveys and prohibitions on timber harvest in 
established buffers around occupied suitable habitat. In May 2005, CDFG 
submitted a petition to the California Fish and Game Commission to 
delist the Siskiyou Mountains salamander throughout its entire range in 
California. In August 2005, CDFG amended the petition by removing that 
portion of the Siskiyou Mountains salamander's range that is now known 
to be occupied by the recently described Scott Bar salamander. The 
private lands affected by the amended petition consititute only 9 
percent of the known range of the Siskiyou Mountains salamander in 
California. The final determination on whether to delist the Siskiyou 
Mountains salamander was scheduled to be made at the Fish and Game 
Commission's January 31, 2007, meeting; however, that decision has been 
postponed pending completion of environmental documents. Because of 
controversy surrounding the proposed delisting, it is uncertain whether 
the existing regulatory protections will be removed in the foreseeable 
future. If existing State regulations are modified in the future, the 
Service can consider such changes in the context of the degree and 
immediacy of potential threats to the Siskiyou Mountains salamander at 
that time. However, because of the small proportion of the species' 
range that occurs on private lands in California, combined with 
evidence that Siskiyou Mountains salamander populations persist in 
disturbed habitats, we find that removal of CESA protections would not 
pose a substantial threat to the species.
    No specific regulatory mechanisms to protect the Siskiyou Mountains 
salamander exist on the approximately seven percent of the species' 
range that occurs on private lands in Oregon. However, most of these 
lands occur as small (one square mile or less) parcels distributed in a 
checkerboard pattern or as isolated parcels within Federal lands where 
management is more favorable for salamanders and serves to maintain 
redundancy, distribution, and connectivity among Siskiyou Mountains 
salamander populations. In addition, research indicates that 
populations of Siskiyou Mountains salamander persist following timber 
harvesting and recover as vegetation is re-established (see Factor A). 
Therefore, the Service believes that the lack of regulatory protections 
on a small proportion of the species' range in Oregon does not pose a 
threat to the species in the foreseeable future.

Summary of Factor D

    The adequacy of existing regulatory mechanisms to protect Siskiyou 
Mountains salamander populations must be evaluated in light of the 
degree of threat potentially posed by the actions being regulated. As 
described above under Factor A, Siskiyou Mountains salamander 
populations may find optimum habitat conditions in mature forest, but 
also occupy a wide range of forest conditions and have been shown to 
persist and recover following disturbances such as timber harvesting 
and fire. Although not specifically aimed at conservation of Siskiyou 
Mountains salamanders, land management guidance such as the NWFP and 
other regulations provide protection of salamander habitat on Federal 
lands which constitute the vast majority of the species' range. 
Although we have determined that the species does not warrant listing 
even in the absence of any reduction in threat resulting from 
implementation of the Conservation Strategy for the Siskiyou Mountains 
salamander (Plethodon stormi) in the Northern Portion of the Range 
(Olson et al. 2007), that Conservation Strategy may provide an added 
layer of security to the Northern Clade of Siskiyou Mountains 
salamander populations.
    Current California regulations provide substantial protection for 
the Siskiyou Mountains salamander on the small percentage of the 
species' range in California that occurs on private lands. The 
California Fish and Game Commission is currently evaluating a petition 
to delist the Siskiyou Mountains salamander, but has not reached a 
decision regarding this action. However, we find that the removal of 
CESA protections would not pose a substantial threat to the species, 
because of the small proportion of the species' range that occurs on 
private lands in California, combined with evidence that Siskiyou 
Mountains salamander populations persist in disturbed habitats. Oregon 
does not provide regulatory protections for the Siskiyou Mountains 
salamander on private lands. However, private lands in Oregon comprise 
only seven percent of the Siskiyou Mountains salamander's entire range 
(both clades) and are scattered among Federal lands that compose the 
vast majority of the species' range.
    Under Section 4(a)(1)(D) the Service must evaluate the adequacy of 
existing regulatory mechanisms rather than speculate about future 
changes to those mechanisms. With the exception of the Survey and 
Manage guidelines, which have been eliminated for future projects on 
Federal lands, we assume that the NWFP and other land management 
regulations will continue as existing regulatory mechanisms that 
provide adequate conservation of Siskiyou Mountains salamanders. If 
Federal or State regulatory mechanisms are modified or eliminated in 
the future, the Service can consider that information when evaluating 
the adequacy of then existing regulatory mechanisms to protect the 
Siskiyou Mountains salamander in the context of the degree and 
immediacy of potential threats to the Siskiyou Mountains salamander at 
that time.
    In light of the ability for Siskiyou Mountains salamander 
populations to persist in managed landscapes, we find that existing 
Federal regulatory mechanisms such as the NWFP and other provisions of 
Federal Land and Resource Management Plans, in combination with the 
Federal Special Status Species programs, offer adequate protection for 
the Siskiyou Mountains salamander and its habitat over the vast 
majority of its range, and conclude that this species is not now, or in 
the foreseeable future, threatened by inadequate regulatory mechanisms.

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

    Other natural or manmade factors that may affect the persistence of 
the Siskiyou Mountains salamander within all or a significant portion 
of its range are climate changes associated with global warming and 
stochastic events, which are rare, chance events, such as epidemics and 
large, severe wildfires.

Climate Change

    There is considerable uncertainty associated with projecting future 
climate changes. This uncertainty is partly due to uncertainties about 
future emissions of greenhouse gases and to differences among climate 
models and simulations (Stainforth et al. 2005, pp. 403-406; Duffy et 
al. 2006, p. 874). We are not aware of any climate change simulations 
for the Klamath-Siskiyou region, but the results of numerous climate 
change simulations for California and the Pacific Northwest have been 
published (see below). Together, these simulations describe a range of 
plausible outcomes from increased emissions of greenhouse gases.

[[Page 4399]]

    All studies we reviewed predicted continued increases in average 
surface temperatures in California and the Pacific Northwest in 
response to increased emissions of greenhouse gases (Leung and Ghan 
1999, p. 2031; Snyder et al. 2002, p. 1; EPRI 2003, p. 95; Hayhoe et 
al. 2004, p. 12422; Cayan et al. 2006, p. 11; Duffy et al. 2006, p. 
873; Maurer 2007, p. 317; Salath[eacute] et al. submitted, pp. 8-9). 
The magnitude of projected increases in annual average temperature 
varied widely among studies, depending on the models and emissions 
scenarios used, from 3 to 10.4 degrees Farenheit ([deg]F) (1.5 to 5.8 
degrees Celsius ([deg]C)), by the year 2100 (EPRI 2003, p. 3; Hayhoe et 
al. 2004, p. 12423; Cayan et al. 2006, pp. 11-14; Maurer 2007, p. 317). 
Simulations consistently project more pronounced temperature increases 
in California during the summer months than during other times of the 
year, 3.9 to 14.9 [deg]F (2.2 to 8.3 [deg]C) by 2100 (Hayhoe et al. 
2004, p. 12422; Cayan et al. 2006, p. 14; Maurer 2007, p. 317). Some 
simulations projected more rapid temperature increases at higher 
elevations than at lower ones (Leung and Ghan 1999, p. 2047; 
Salath[eacute] et al. submitted, pp. 10-12). Most researchers 
attributed this difference to a snow-albedo feedback effect; this 
occurs when increased surface temperatures cause earlier and faster 
snow melt, which, in turn, allows more absorption of heat by the ground 
and further increases in surface temperatures.
    Increased average surface temperatures could cause soils used by 
Siskiyou Mountains salamanders to become warmer, and possibly drier, 
during the dry season. If this occurs, it could negatively affect these 
species because they are associated with cool, moist soil conditions 
(see Habitat Associations above). However, we expect that the Siskiyou 
Mountains salamanders will be somewhat buffered from changes to soil 
surface conditions because they are primarily active below ground 
during the dry season. Salamanders at shallow sites may be more 
negatively affected by drying and heating of the soil surface than 
those at deeper sites since they will be less able to respond to 
changing soil microclimates with vertical movements. Increased surface 
temperatures could have unpredictable indirect effects on these 
species: For example, through effects on vegetation, disturbance 
regimes, competitors, predators, or prey.
    Reviews of a large number and variety of climate change simulations 
found that projected changes to precipitation in California were highly 
variable but clustered around no change or a slight increase in annual 
precipitation (Cayan et al. 2006, p. 17; Maurer 2007, p. 317). Warming 
temperatures are consistently projected to increase the proportion of 
precipitation that falls as rain rather than as snow in California and 
the Pacific Northwest (Leung and Ghan 1999, p. 2041; Snyder et al. 
2002, p. 3; Hayhoe et al. 2004, p. 12425; Cayan et al. 2006, p. 31; 
Maurer 2007, p. 319). Earlier and more rapid snowmelt and decreases in 
the proportion of precipitation that falls as snow are expected to 
cause declines in spring snowpacks (Hayhoe et al. 2004, p. 12422; Cayan 
et al. 2006, p. 31; Maurer 2007, p. 309). Declines in spring snowpacks 
have already occurred in some areas and are correlated with global 
warming trends (Mote 2003, pp. 1-4). Some areas will experience 
increased cloud cover as surface temperatures continue to increase 
(Croke et al. 1999, pp. 2128-2134). One model projected a greater 
increase in low cloud cover during spring in the Pacific Northwest, 
especially near the coast (Salath[eacute] et al. submitted, pp. 14-16).
    Lower proportions of snow versus rain and earlier and faster 
snowmelt could enable the Siskiyou Mountains salamanders to become 
surface active earlier in the spring. We currently do not know whether 
or how a shift in the timing of surface activity might affect the 
viability of these species. Little is known about the physiological 
sensitivities of the Siskiyou Mountains salamanders to temperature, but 
an increase in spring cloud cover could directly benefit them by 
moderating daily temperature ranges during their periods of surface 
activity. Superficially, increased precipitation might also directly 
benefit the species, while decreased precipitation might negatively 
affect it. For example, changes to the timing and amount of 
precipitation could alter the length or frequency of the species' 
periods of surface activity or the size or location of its geographic 
range. Changes to cloud cover or the amounts, timing, and form of 
precipitation could also have complex indirect effects on the species; 
for example, through influences on vegetation, disturbance regimes, 
competitors, predators, or prey. Evaluation of the potential effects of 
changes to precipitation on the Siskiyou Mountains salamander should 
become more meaningful as emissions scenarios, climate change models, 
and our knowledge of these species continue to improve.
    Vegetation modeling by Lenihan et al. (2003a, pp. 1-41; 2003b, pp. 
1667-1681) projected that increased emissions of greenhouse gases will 
cause large-scale replacement of evergreen conifer forest (e.g., 
Douglas fir-white fir) with mixed evergreen forest (e.g., Douglas-fir-
tanoak) in the Klamath-Siskiyou region. This redistribution of 
vegetation types is predicted to occur under conditions created by two 
contrasting climate change models (Lenihan et al. 2003a, pp. 23-25). 
Because Siskiyou Mountains salamanders already occur within mixed 
evergreen forest, we do not anticipate a direct negative effect to the 
species from this potential change. However, the species may shift its 
range to higher elevations, following elevational changes in climate 
and vegetation. Numerous indirect effects of community composition 
shifts on the Siskiyou Mountains salamander could occur, but the net 
effect of these shifts is currently impossible to predict owing to the 
lack of information about this species' ecology.
    Despite variability in climate change simulations, consistent 
projections for warmer summers, reduced spring snowpacks, and earlier 
and more rapid snowmelt suggest that forests in California and the 
Pacific Northwest will experience longer fire seasons and more 
frequent, extensive, and severe fires in the future (Flannigan et al. 
2000, pp. 221-229; Lenihan et al. 2003a, p. 18; Whitlock et al. 2003, 
pp. 13-14; McKenzie et al. 2004, pp. 897-898). However, inconsistent 
predictions for precipitation, including increased cloud cover and 
rainfall, make this outcome uncertain.
    The Siskiyou Mountains salamander has experienced other large 
changes to global and regional climates during its history. For 
example, global temperatures during the Pliocene warm period (5 to 3 
million years ago) were approximately 5.4 [deg]F (3 [deg]C) higher than 
today (Ravelo et al. 2004, p. 263). More recently, several large 
changes to climate, fire regimes, and vegetation occurred in the 
Klamath-Siskiyou region during the Holocene (approximately 12,000 years 
to present day) (e.g., Mohr et al. 2000). Little is known about how the 
Siskiyou Mountains salamander responded to prehistoric climate changes 
or how those responses might inform us about the impacts of future 
changes.

Stochastic Events

    Siskiyou Mountains salamanders have relatively small geographic 
ranges and limited dispersal abilities. Analyses of the fossil record 
and of currently threatened species suggest that species with these 
characteristics are at a higher risk of extinction than are mobile, 
widely distributed species (Jablonksi

[[Page 4400]]

1986; Manne et al. 1999; Dynesius and Jansson 2000; Jones et al. 2003; 
Payne and Finnegan 2007). Stochastic (rare, chance) events such as 
epidemics or large, severe fires can threaten the persistence of 
species with restricted ranges because a single event can occur within 
all or a large portion of their ranges. Species that are relatively 
sedentary are probably less able than mobile animals to escape 
stochastic events and their effects, or to recolonize parts of their 
range where they have been extirpated. Some researchers have suggested 
that the Siskiyou Mountains salamander is rare and patchily 
distributed, which could further increase the species' risks of 
extinction. However, the evidence cited above suggests that this 
salamander is in fact well distributed within its range, that it likely 
occurs at high densities in some areas, and that it persists in areas 
that have experienced disturbances (see Range and Distribution, and 
Factor A).
    Epidemics and large, severe fires are two kinds of stochastic 
events that could negatively affect populations of the Siskiyou 
Mountains salamander. However, these events are unlikely to threaten 
the persistence of the species across its range. The only lethal 
disease we are aware of that could behave as an epidemic in populations 
of this salamander is chytridiomycosis (Batrachochytrium 
dendrobatidis), but this species does not appear likely to contract 
this disease and the Siskiyou Mountains salamander's life history makes 
it unlikely that this disease would spread as an epidemic (see Factor C 
above). The Siskiyou Mountains salamander is probably more likely to 
experience large, severe wildfires than epidemics in the foreseeable 
future. Wildfires can occur over large areas relative to the range of 
the Siskiyou Mountains salamander. For example, 499,965 ac (202,329 ha) 
burned during the 2002 Biscuit Fire in southwestern Oregon and 
northwestern California, largely outside of the range of the 
salamanders. Approximately 44 percent of the area (219,985 ac (89,025 
ha)) was severely burned (USDA and USDI 2004). In comparison, the 
species range of the Siskiyou Mountains salamander is 423,155 ac 
(171,241 ha). However, Siskiyou Mountains salamanders appear to be 
relatively resilient to disturbances (see Factor A above), having 
evolved in a region where large wildfires are characteristic. Further, 
past fire behavior and modeling of future fire behavior suggest that 
large, severe fires in this region will have a mosaic of effects, 
leaving unburned and lightly burned patches of suitable habitat for the 
species in some areas (see Factor A above).

Summary of Factor E

    Uncertainty is associated with predicting future climate changes, 
but simulations have consistently projected continued increases in 
average surface temperatures, reduced spring snowpacks, and a lower 
proportion of precipitation falling as snow during this century. Given 
its physiology, this species may be strongly affected, positively or 
negatively, by changes to precipitation patterns. However, projections 
of future patterns of precipitation are highly variable for northern 
California and southern Oregon, precluding any reliable prediction of 
future effects on salamander populations.
    The Siskiyou Mountains salamander has a relatively small geographic 
range, restricted habitat associations, and limited dispersal 
abilities, which could make it more vulnerable to stochastic events 
such as large, severe fires than species without these characteristics. 
Large, severe fires are also expected to increase in frequency in the 
Klamath-Siskiyou region due to global warming and other anthropogenic 
factors. However, the high variability of wildfire effects at landscape 
scales, coupled with the apparent ability of the species to persist and 
eventually recover following habitat disturbance (see Factor A above), 
indicates that the Siskiyou Mountains salamander has a high likelihood 
of persistence in the foreseeable future. In addition, land management 
agencies within the ranges of the salamanders are actively conducting 
fuels management treatments to reduce the likelihood of wide-scale 
catastrophic fire. The future effectiveness of these treatments is 
unknown, but evidence suggests that at least local reductions in fire 
severity will be achieved. Therefore, we conclude that the Siskiyou 
Mountains salamander is not now, or in the foreseeable future, 
threatened by the individual or cumulative effects of climate change, 
or stochastic events such as epidemics or large, severe wildfires 
across its range.

Finding

    We have carefully assessed the best scientific and commercial 
information available regarding threats faced by the Siskiyou Mountains 
salamander. We have reviewed the petition, information available in our 
files, and all information submitted to us following our 90-day 
petition finding (72 FR 14750; March 29, 2007). We also consulted with 
recognized salamander experts and Federal land managers, and arranged 
for researchers to initiate field studies to assess the distribution of 
genetic entities within the salamander complex, and demographic 
response of these species to forest structure.
    The petitioners' primary argument for listing the Siskiyou 
Mountains salamander is founded on a chain of inferences, which may be 
simplified into the following: (1) The salamanders are highly dependent 
on old growth forest conditions; (2) disturbances such as timber 
harvesting that modify forest structure will extirpate populations; (3) 
the extent and magnitude of such disturbances are sufficient to 
threaten the species with extinction in the immediate future; (4) 
therefore, highly restrictive regulatory mechanisms are critical to 
prevent extirpation of populations by timber harvesting or wildfire; 
and, finally, (5) existing regulatory mechanisms are inadequate to 
ameliorate the perceived threats to the species. We find that there is 
little evidence to support any of the five above-mentioned assertions.
    The available information indicates that, while habitat conditions 
associated with dense mature forests may be optimal for the Siskiyou 
Mountains salamander, populations occupy a wide range of habitats that 
provide the requisite elements of shading, moisture, and cover. 
Salamander populations are found in a wide variety of forest 
conditions, including areas with evidence of past disturbances. Local 
abundance and fitness of populations may be negatively affected by more 
intensive timber harvesting and wildfires, but salamander populations 
appear to persist and recover as vegetation is re-established following 
such intense disturbances, and these intensive timber harvest practices 
such as clear-cutting are severely restricted on the Federal lands that 
constitute the majority of the species' range. Less-intensive harvest 
practices appear to have relatively minor or short-term impacts on 
salamander abundance, and there are many known populations on managed 
timberlands. There is no reliable evidence that indicates loss of 
populations or curtailment of the species' ranges has occurred.
    Federal lands managed under the provisions of the NWFP comprise the 
majority of the Siskiyou Mountains salamander's range. The NWFP acts to 
protect salamanders and their habitat via a system of reserves and land 
management guidelines that dramatically reduce the likelihood of large-
scale reduction of suitable habitat. Additional land allocations and 
management guidance in Federal land management planning documents

[[Page 4401]]

(retention areas, Roadless Areas) and the Federal agencies' Special 
Status Species programs provide additional layers of security against 
any long-term threats posed by timber harvesting or other land 
management activities.
    Private lands comprise only about 10 percent of the species' range, 
and receive a relatively greater amount of timber harvesting. 
Currently, the Siskiyou Mountains salamander is listed under CESA and 
receives substantial protection on private lands in California; 
however, the future of these protections is uncertain. Regardless of 
the eventual CESA status of the species in California, habitat impacts 
on private land are not expected to pose a substantial threat to the 
Siskiyou Mountains salamander, because: (1) Private lands constitute a 
small minority of the species' range; (2) private lands exist in a 
checkerboard pattern of small (less than one square mile) parcels 
interspersed among Federal lands where management is more favorable and 
therefore, acts to maintain redundancy, distribution, and connectivity 
among populations within the mix of Federal and private lands; (3) 
salamander populations appear to persist and recover following timber 
harvesting; and (4) many salamander populations are known to occur on 
private timberlands despite a long history of timber harvesting.
    Wildfires are expected to occur and may reduce habitat quality for 
some salamander populations; however, the effects of wildfire on 
salamander habitat are temporary and populations appear to recover as 
vegetation recovers. Wildfires in the Klamath-Siskiyou region typically 
burn in a mosaic pattern of intensities, leaving a variety of habitat 
conditions for salamanders within burned areas. We also note that 
Federal Federal land management agencies are actively planning and 
conducting fuels reduction treatments to reduce the threat of large, 
stand-replacing wildfires within the range of the Siskiyou Mountains 
salamander.
    Within its relatively small range, populations of Siskiyou 
Mountains salamanders are well distributed, and abundance within 
populations can be high. There are 516 known locations for this 
species, and large areas supporting suitable habitat have not been 
surveyed. These population characteristics, combined with the species' 
apparent ability to persist and recover following habitat disturbance, 
indicate that the Siskiyou Mountains salamander is resilient to 
stochastic events such as large wildfires. Our evaluation of climate 
change modeling for the geographic area inhabited by the salamanders 
does not support the contention that climate change poses a substantial 
threat to Siskiyou Mountains salamanders. Although most of the 
available models predict increases in average temperatures, models were 
inconsistent with regard to future precipitation; increases in annual 
precipitation and cloud cover are a plausible outcome and could act to 
ameliorate any negative impacts caused by increased temperatures. It is 
not currently possible to forecast the specific effects of future 
climate on salamander populations.
    Our evaluation of the threats to the Siskiyou Mountains salamander 
leads us to the conclusion that several factors act cumulatively to 
assure the continued existence of well-distributed, viable populations 
of this species into the foreseeable future. These are: (1) Populations 
are demonstrated to persist in a wide variety of habitat conditions; 
(2) populations appear to be somewhat resilient to habitat disturbances 
such as timber harvesting and fire; (3) to the extent that habitat 
disturbances have negative effects to salamander populations, 90 
percent of the species' range is protected from substantial negative 
impacts by existing Federal land management regulations such as the 
NWFP and other regulations that provide protection for their habitat; 
(4) private timberlands constitute only 10 percent of the species' 
range, and currently support numerous salamander populations; and (5) 
the 516 currently known locations of this species are well-distributed 
spatially and large areas of suitable habitat have yet to be surveyed. 
Therefore, we do not find that the Siskiyou Mountains salamander is in 
danger of extinction (endangered) now, nor is it likely to become 
endangered within the foreseeable future (threatened) across its range. 
Therefore, listing the species range-wide as threatened or endangered 
under the Act is not warranted at this time.

Distinct Population Segment

    As stated above, the Siskiyou Mountains salamander can be separated 
into two clades, the Applegate salamander and the Grider salamander 
and, therefore, may be considered as two distinct population segments 
(DPSs), if indeed, they meet the criteria to be defined as such. 
Section 2(16) of the Act defines ``species'' to include ``any species 
or subspecies of fish and wildlife or plants, and any distinct 
vertebrate population segment of fish or wildlife that interbreeds when 
mature'' (16 U.S.C. 1532 (16)). To interpret and implement the DPS 
provisions of the Act and Congressional guidance, the Service and the 
National Marine Fisheries Service (now the National Oceanic and 
Atmospheric Administration--Fisheries), published a Policy Regarding 
the Recognition of Distinct Vertebrate Population Segments in the 
Federal Register (DPS Policy) on February 7, 1996, (61 FR 4722). Under 
the DPS policy, three factors are considered in the decision concerning 
the establishment and classification of a possible DPS. These are 
applied similarly for additions to the list of endangered and 
threatened species. These factors are (1) the discreteness of a 
population in relation to the remainder of the species to which it 
belongs, (2) the significance of the population segment to the species 
to which it belongs, and (3) the population segment's conservation 
status in relation to the Act's standards for listing, delisting, or 
reclassification (i.e., is the population segment endangered or 
threatened?).

Discreteness

    Citing the Services' DPS policy (61 FR 4722) and the best available 
information, the June 2006 petition suggests that the Siskiyou 
Mountains salamander can be separated into two discrete populations 
based on reproductive isolation. 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.
    Phylogenetic studies of the Siskiyou Mountains salamander 
demonstrate that this species consists of two distinct genetic 
lineages: the Applegate salamander (populations within the Applegate 
River drainage and north of the Siskiyou Crest) and the Grider 
salamander (populations south of the Siskiyou Crest and adjacent to the 
Klamath River) (Pfrender and Titus 2001, pp. 5-6; DeGross 2004, pp. 24-
44; Mahoney 2004, p. 8; Mead et al. 2005, pp. 163-166). Mead et al. 
(2005, p. 168) describe these lineages as ``a major phylogenetic 
subdivision within P. stormi.'' Mead et al. (2005, p. 168) estimated an 
average of 2.22 percent

[[Page 4402]]

mitochondrial DNA sequence divergence between the Applegate and Grider 
salamanders, compared with 11.5 percent and 11.68 percent sequence 
divergence between Scott Bar salamander and the Applegate and Grider 
salamanders, respectively. An additional genetic distinction between 
the two lineages is the almost complete lack of genetic variation 
within and among Applegate populations, likely the result of range 
expansion and genetic bottleneck as individuals dispersed into the 
southern reaches of the Applegate watershed (Pfrender and Titus 2001, 
pp. 5-6).
    The geographic ranges occupied by the Applegate and Grider 
salamanders are separated by the Siskiyou Crest, a high-elevation ridge 
system unlikely to permit population connectivity between the groups. 
Analyses of mitochondrial DNA indicate that, while the ancestral 
lineage of the Applegate salamander originated south of the Siskiyou 
Crest, the two groups diverged over four million years ago (DeGross and 
Bury 2007, p. 3), further supporting the conclusion that the Siskiyou 
Crest constitutes an effective barrier between the groups.
    The Applegate and Grider salamanders are markedly separated as a 
consequence of physical (geographic) features, and as a consequence 
exhibit genetic divergence as well. We, therefore, conclude that the 
two groups are discrete under our DPS policy.

Significance

    If a population segment is considered discrete under one or more of 
the conditions described in our DPS policy, its biological and 
ecological significance will be considered in light of Congressional 
guidance that the authority to list DPSs be used ``sparingly'' while 
encouraging the conservation of genetic diversity. In making this 
determination, we consider available scientific evidence of the 
discrete population segment's importance to the taxon to which it 
belongs. Since 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 
does provide four possible reasons why a discrete population may be 
significant. As specified in the DPS policy (61 FR 4722), 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 historic range; or
    (4) Evidence that the discrete population segment differs markedly 
from other populations of the species in its genetic characteristics.
    A population segment needs to satisfy only one of these criteria to 
be considered significant. Furthermore, the list of criteria is not 
exhaustive; other criteria may be used as appropriate.
    The ranges and population distribution of the Applegate and Grider 
salamanders suggest that the loss of either group would result in a 
significant gap in the range of the Siskiyou Mountains salamander. The 
estimated ranges of the Applegate and Grider salamanders constitute 
about 59 percent and 41 percent, respectively, of the overall range of 
the Siskiyou Mountains salamander. Loss of such a substantial portion 
of the species' range, coupled with the dispersal barrier posed by the 
Siskiyou Crest, would be significant to the distribution of the 
species. An additional consideration is the metapopulation-level 
redundancy that the two groups provide each other. Climatic conditions 
and fire regimes differ on either side of the Siskiyou Crest, and the 
elevation of the Crest itself serves as a barrier to wildfires. Large-
scale disturbances such as catastrophic wildfire may therefore act 
independently on either clade; allowing the continued persistence of 
the species in the event of substantial losses of one group.
    The uneven distribution of genetic variation across the range of 
the Siskiyou Mountains salamander places a disproportionate 
significance on each group for the maintenance of genetic diversity in 
the species. The Applegate salamander exhibits a strikingly low level 
of genetic variation, and is divergent from the more variable Grider 
salamander (Pfrender and Titus 2001, pp. 5-6; Mead et al. 2005, pp. 
166-169). Loss of either genetically distinct group would pose a 
substantial reduction in genetic diversity of Siskiyou Mountains 
salamander. Therefore, we consider the Applegate and Grider salamanders 
significant to the taxon as a whole under our DPS policy.

Conclusion of Distinct Population Segment Review

    Based on the best scientific and commercial information available, 
as described above, we find that under our DPS policy, the Applegate 
and Grider salamander groups of the Siskiyou Mountains salamander are 
discrete and each are significant to the overall species. Because the 
Applegate and Grider salamanders are both discrete and significant, 
they warrant recognition as separate DPSs under the Act.
    Since we have identified the Applegate and Grider salamanders as 
two separate, valid DPSs, we will evaluate each DPS with regard to its 
potential for listing as threatened or endangered using the five 
listing factors enumerated in Section 4(a) of the Act. Our evaluation 
of the Applegate salamander DPS follows.

Applegate Salamander Distinct Population Segment

    As described above, Section 4 of the Act (16 U.S.C. 1533) and 
implementing regulations (50 CFR part 424) describe procedures for 
adding species to the Federal Lists of Endangered and Threatened 
Wildlife and Plants. Under section 4(a), we may list a species on the 
basis of any of five factors: (A) The present or threatened 
destruction, modification, or curtailment of its habitat or range; (B) 
overutilization for commercial, recreational, scientific, or 
educational purposes; (C) disease or predation; (D) the inadequacy of 
existing regulatory mechanisms; or (E) other natural or manmade factors 
affecting its continued existence.
    An endangered species is defined by the Act, with exception, as 
``any species which is in danger of extinction throughout all or a 
significant portion of its range.'' A threatened species is defined as 
``any species which is likely to become an endangered species within 
the foreseeable future throughout all or a significant portion of its 
range.'' A species is defined by the Act 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.''

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

    Our understanding of the habitat associations of the Applegate 
salamander DPS, and the potential effects of habitat perturbations such 
as timber harvest and fire on this

[[Page 4403]]

salamander, is based primarily on research conducted across the range 
of the entire Siskiyou Mountains salamander Complex. The available 
information indicates that the members of the Complex have similar 
physiological and behavioral characteristics, and consequently similar 
habitat associations. This conclusion is supported by Welsh et al. 
(2007a, p. 31), who state that the genetic subunits of Siskiyou 
Mountains salamander ``do little if anything to alter their basic eco-
physiological limits (e.g., Spotila 1972; Feder 1983) and consequent 
similar environmental requirements imposed by the plethodontid life 
form.'' We recognize that the range of the Applegate salamander DPS is 
roughly 60 percent of the area occupied by the entire Siskiyou 
Mountains salamander, and that the relative magnitude of effects caused 
by habitat perturbations may be different at this smaller spatial 
scale. We have incorporated these differences of scale into our 
analysis. Given this caveat, we believe that the potential effects of 
timber harvesting, fire, and other habitat perturbations on the 
Applegate salamander DPS are the same as those described previously for 
the Siskiyou Mountains salamander. To avoid redundancy, these effects 
are summarized below; further detail and citations may be found in the 
Factor A analysis for the Siskiyou Mountains salamander.

Effects of Timber Harvesting on the Applegate Salamander DPS

    Rigorous research of the effects of timber harvesting on these 
salamanders is lacking, but the available evidence suggests that 
intensive timber harvest practices such as clear-cutting have a short-
term (30 years) negative impact on abundance, age structure, and body 
condition of this DPS. However, it is also clear that the salamanders 
frequently persist in intensively harvested areas, and that populations 
recover as vegetation is re-established (Welsh et al. 2007b). There is 
no information indicating that populations are extirpated in 
intensively harvested sites. Alternative timber harvesting methods such 
as thinning and helicopter yarding have not been shown to have negative 
effects on populations of this DPS.

Extent and Magnitude of Timber Harvesting Effects on the Applegate 
Salamander DPS

    The extent and magnitude of potential effects caused by timber 
harvesting are strongly limited by existing land management regulations 
on the majority of the range of this DPS. Approximately 85 percent of 
the range of the Applegate salamander DPS consists of Federal lands 
managed under the provisions of the NWFP; 66 percent is administered by 
the USFS and 19 percent by the BLM. Roughly 33 percent of the range 
occurs within reserves (Late-successional Reserves, Wilderness, 
Riparian Reserves) withdrawn from scheduled timber harvesting; 42 
percent of the range is in the Applegate Adaptive Management Area; and 
9 percent is in Matrix. Of the three members within the Siskiyou 
Mountains salamander Complex, the Applegate salamander DPS has the 
lowest proportion of its range protected in reserves.
    The rate and intensity of timber harvesting has declined 
substantially on Federal lands within the range of the Applegate 
salamander DPS during the past 20 years. Annual timber harvesting on 
the Rogue River National Forest, which comprises 66 percent of the DPS 
range, declined from an average of 182 million board feet during the 
1980s to 8 million board feet per year from 2000 to 2006, a decrease of 
96 percent (USDA 2007c). The Applegate Ranger District, which comprises 
roughly 66 percent of the DPS range, has completed only one timber sale 
since 1996 (Clayton 2007b). Similarly, the rate of timber harvest has 
declined substantially on BLM lands within the range of the Applegate 
salamander DPS. Mean annual harvest on the BLM Ashland Resource Area 
declined from 2,240 ac (907 ha) per year between 1995 and 2000, to 664 
ac (269 ha) per year between 2001 and 2007; less than 270 ac (109 ha) 
per year have been harvested since 2003 (USDI 2007a). The intensity of 
timber harvest practices on Federal lands has declined dramatically as 
well. For example, on the BLM's Ashland Resource Area, intensive 
harvest methods such as clear-cutting have declined from 54 percent of 
acres harvested in the mid-1990s, to less than one percent of annual 
harvest since 2001 (USDI 2007a). The likelihood that a substantial 
proportion of the Applegate salamander DPS will be affected by 
intensive timber harvesting is greatly reduced by the long-term 
declining trend in the rate and intensity of timber harvesting. The 
BLM's proposal to increase timber harvest levels by revising their RMPs 
has an uncertain outcome, and we see no reason to forecast a 
significant increase in timber harvest levels in the foreseeable 
future.
    Intensive timber harvesting practices such as clear-cutting and 
shelterwood removal are more prevalent on private timberlands, which 
comprise only 15 percent of the range of the Applegate salamander DPS. 
Approximately 12 percent of the DPS range occurs on private timberlands 
in Oregon; 3 percent lies in California. The majority of private lands 
within the range of the Applegate salamander DPS occur as small parcels 
(typically one square mile or less) in a checkerboard pattern 
surrounded by Federal lands, or as small isolated parcels. Populations 
of the Applegate salamander DPS on private lands may be affected by 
timber harvesting but are dispersed among populations on Federal lands 
where management is more favorable. Since the distribution of private 
lands occurs within a larger matrix of Federal lands, this acts to 
disperse any negative impacts of timber harvesting on Applegate 
salamander DPS populations and maintains redundancy, distribution, and 
connectivity among salamander populations. Therefore, no one area 
within the range of the Applegate salamander DPS has significantly 
greater threats from timber harvesting on private lands.

Wildfire

    Based on the best scientific and commercial information available, 
we believe the potential effects of wildfire on the Applegate 
salamander DPS are similar to those described previously for the 
Siskiyou Mountains salamander. When they occur, wildfires typically 
burn in a range of intensities, resulting in a mosaic of habitat 
effects. Intense, stand-replacing fire likely reduces habitat quality 
for this DPS by reducing overstory cover and consuming moss, duff and 
forest floor litter, thereby modifying suitable microclimate habitat. 
However, as shown for the effects of intensive timber harvesting, 
Siskiyou Mountains salamander populations appear to persist and recover 
as vegetation is re-established after severe habitat disturbances. The 
degree to which wildfires affect the viability of salamander 
populations is unknown, but it is likely that large-scale intense 
wildfires may negatively affect some populations.
    The potential threat posed by wildfire to the Applegate salamander 
DPS was evaluated by Olson et al. (2007, p. 25, Appendix 2 p. 5). The 
authors combined a habitat suitability model (Reilly et al. 2007) with 
spatial data on various risk factors such as wildfire hazard and NWFP 
land use allocations into a GIS and developed a range-wide map 
depicting risk to persistence of salamander populations. Extensive 
areas of highly suitable habitat and lower fire hazard were predicted 
on north-facing slopes, such as the north slope of the

[[Page 4404]]

Siskiyou Crest (Olson et al. 2007, Appendix 2 p. 8).
    While there is uncertainty concerning the potential population-
level effects of wildfire on the Applegate salamander DPS, we expect 
that wildfires will occur and may reduce habitat quality for some 
salamander populations. However, the effects of wildfire are unlikely 
to result in widespread loss of population viability because: (1) Fires 
typically burn in a mosaic of effects, leaving a variety of habitat 
conditions for salamanders occupying burned areas; and (2) these 
salamanders persist in disturbed areas and recover as vegetation 
recovers, allowing for persistence and recovery of local salamander 
populations. In addition, land management agencies within the range of 
this DPS are actively conducting fuels management treatments to reduce 
the likelihood of wide-scale catastrophic fire. The future 
effectiveness of these treatments is unknown, but evidence suggests 
that at least local reductions in fire severity will be achieved.

Direct Disturbance: Roads and Road Construction, Mining, and Rock 
Quarrying

    As described under Factor A for the Siskiyou Mountains salamander, 
activities that physically alter the talus substrates occupied by the 
Applegate salamander DPS have the potential to reduce habitat quality 
or remove habitat. In addition, some research suggests that forest 
roads may pose a barrier to these salamanders, reducing dispersal and 
connectivity among populations. We find that, while it may reasonably 
be expected that crushing or removal of talus habitat during road 
construction, mining, or rock quarrying could negatively affect 
Applegate salamander populations, these activities affect only a very 
small area of the DPS's range. Further, numerous records exist of the 
salamanders occupying road cuts and sites with historical mining 
activity, and the rate of road construction, which is typically 
associated with access for timber harvesting, has declined 
significantly as timber harvest levels have decreased. There is little 
potential for a substantial portion of Applegate salamander DPS 
populations to be affected by direct disturbance from road 
construction, mining, or rock quarrying. For these reasons, we conclude 
that road construction, mining and rock quarrying do not pose a 
substantial threat to this DPS; a conclusion echoed by species experts 
(Olson et al. 2007, p. 17).

Summary of Factor A

    While intensive timber management practices such as clear-cutting 
appear to have short-term negative effects on abundance of Applegate 
salamanders, this practice is severely restricted on Federal lands, 
which constitute the majority of the DPS's range. Less-intensive 
harvest practices appear to have relatively minor or short-term impacts 
to salamander abundance, and the available evidence suggests that 
salamander populations persist in a broad range of forest habitat 
conditions and under different management practices.
    Current management on Federal lands under the provisions of the 
NWFP protects salamander habitat via a system of reserves and 
management guidelines that dramatically reduce the likelihood of large-
scale reduction of suitable or occupied habitat; additional Federal 
land management direction and the Special Status Species programs 
provide additional security to salamander populations on non-reserved 
Federal lands. Management practices on private timberlands may 
negatively affect some populations of the Applegate salamander DPS; 
however, due to the patchy distribution of private lands within the 
larger matrix of Federal lands, and the ability of these salamanders to 
persist in managed habitats, we conclude that habitat modifications on 
this small portion of the Applegate salamander DPS's range do not 
constitute a substantial threat to the DPS.
    Wildfires are expected to occur and may reduce habitat quality for 
some salamander populations; however, the effects of wildfires on 
salamander habitat are temporary and populations appear to recover as 
vegetation recovers. Wildfires typically burn in a mosaic pattern of 
intensities, leaving a variety of habitat conditions for salamanders 
within burned areas. In addition, Federal land management agencies are 
planning and conducting fuels reduction treatments to reduce the threat 
of stand-replacing wildfires within the range of the Applegate 
salamander.
    Although relatively undisturbed mature forests may provide optimum 
habitat for Applegate salamanders; these salamanders have been shown to 
exist in a range of habitat conditions that have experienced timber 
harvesting, wildfire, and other disturbances such as mining and 
quarrying, and evidence suggest that populations persist and recover 
following habitat disturbance. Intense disturbances such as clear-
cutting are highly limited by current land-use regulations, and along 
with rock quarrying and road construction constitute a tiny fraction of 
the DPS's habitat. Therefore, we conclude that the Applegate salamander 
DPS is not now, or in the foreseeable future, threatened by 
destruction, modification, or curtailment of its habitat across its 
range.

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

    We are not aware of any information that indicates overutilization 
for commercial, recreational, scientific, or educational purposes 
threatens the Applegate salamander DPS, now or in the foreseeable 
future, across its range.

Factor C: Disease or Predation

    Chytridiomycosis is a relatively recently described epidermal 
infection of amphibians caused by the chytrid fungus Batrachochytrium 
dendrobatidis. This fungus requires moisture for survival (Johnson and 
Speare 2003, p. 922) and is therefore more likely to pose a threat to 
aquatic amphibians than to terrestrial ones. As described for the 
Siskiyou Mountains salamander, we do not anticipate that the Applegate 
salamander DPS will be exposed to this disease or that exposure would 
lead to transmission through significant portions of its range. 
Salamanders composing this DPS are not associated with bodies of water, 
occur in a characteristically dry environment, are only active above 
ground for brief and intermittent periods during the year, and appear 
to have limited dispersal abilities. Given these circumstances, we 
believe that the Applegate salamander DPS is unlikely to be exposed to 
diseased water or infected aquatic amphibians and, if infected, 
salamanders are unlikely to transmit the disease between populations.
    The Service is not aware of any predators that potentially pose a 
threat to the species. We, therefore, conclude that the Applegate 
salamander DPS is not now, or in the foreseeable future, threatened by 
disease or predation across its range.

Factor D: Inadequacy of Existing Regulatory Mechanisms

Federal Lands

    Federal lands managed under the provisions of the NWFP comprise the 
majority of the Applegate salamander's range. The NWFP acts to protect 
salamanders and their habitat via a system of reserves and land 
management guidelines that

[[Page 4405]]

dramatically reduce the likelihood of large-scale reduction of suitable 
habitat.

Northwest Forest Plan Survey and Manage Mitigation Measure Standards 
and Guidelines

    The provisions and current status of the Survey and Manage Program 
are described under Factor D for the Siskiyou Mountains salamander. The 
Survey and Manage Program contains specific guidance for the Applegate 
salamander DPS, requiring the identification of high-priority sites 
that will be managed to provide a reasonable assurance of species 
persistence. While the Survey and Manage Program currently provides 
protection for the Applegate salamander DPS on Federal lands, we assume 
for purposes of this finding that the Survey and Management Program is 
eliminated for future projects on Federal lands and management of the 
Applegate salamander DPS will be conducted under the USFS's Special 
Status Species Program and the BLM's Sensitive Species Program. While 
these programs do not specify protections for the Applegate salamander 
DPS, they contain provisions for development of Conservation Strategies 
that provide a reasonable assurance of species persistence.

Conservation Agreements

    The final Conservation Strategy for the Siskiyou Mountains 
Salamander, Northern Portion of the Range (Olson et al. 2007), is 
currently being implemented by the USFS and BLM on Federal lands 
occupied by the Applegate salamander DPS. The Conservation Strategy was 
authored by four of the most-published scientific experts on this 
species (D. Olson, D. Clayton, H. Welsh, and R. Nauman, among others), 
and incorporates habitat modeling and risk assessment in the evaluation 
of species persistence and distribution within the strategy area. The 
Conservation Strategy is described in detail in the Background section 
and under Factor D for the Siskiyou Mountains salamander, which is 
incorporated by reference here. However, because of the limited nature 
of the threats addressed by the Conservation Strategy, we did not rely 
on it in determining whether listing the Applegate salamander is 
warranted.

Western Oregon Plan Revisions

    The BLM's proposed changes to its existing Resource Management 
Plans through the WOPR contain provisions that have the potential to 
increase timber harvesting within the range of the Applegate salamander 
DPS (see Factor D for Siskiyou Mountains salamander). The WOPR proposal 
affects only Federal lands administered by the BLM, which constitute 
approximately 19 percent of the range of the Applegate salamander DPS. 
The WOPR DEIS is currently in the public review period, and we cannot 
at this time predict which alternative, including the no-action 
alternative, will be selected or evaluate the potential effects to 
Applegate salamander populations on BLM lands.
    While the potential effects of possible RMP changes on the 19 
percent of Applegate salamander DPS' range that occurs on BLM lands are 
unknown, NWFP land-use allocations and management direction provides 
substantial protection for the DPS and its habitat. If existing Federal 
management for the Applegate salamander DPS is modified in the future, 
the Service can consider any such changes in the context of the degree 
and immediacy of potential threats to the DPS at that time.

Private Lands and State Regulations

    Approximately 12 percent of the range of the Applegate salamander 
DPS occurs on private lands located in Oregon, and 3 percent occurs on 
private lands located in California. In Oregon, no regulatory 
mechanisms exist to protect this DPS on private lands. In California, 
the Siskiyou Mountains salamander (both Applegate and Grider 
populations) is listed as a threatened species and receives substantial 
protections pursuant to CESA. These protections include the requirement 
of surveys prior to project implementation and prohibitions on timber 
harvest in established buffers around occupied suitable habitat. There 
is some uncertainty concerning the future of CESA protections for 
Applegate salamander DPS populations on the small fraction of the DPS's 
range that occurs in California (see Factor D for Siskiyou Mountains 
salamander). Regardless of the future status of protections for the 
Siskiyou Mountains salamander under CESA, those protections only apply 
to 3 percent of the Applegate salamander DPS's range, and the potential 
removal of these protections will not pose a significant threat to this 
DPS.
    As described under Factor A, we find that there is little evidence 
to suggest that members of the Applegate salamander DPS are extirpated 
by timber harvesting and other habitat disturbances. Research indicates 
that populations of these salamanders persist following intensive 
timber harvest and recover as vegetation is re-established. Less 
intensive harvest practices appear to have little effect on 
populations. Therefore, we find that the lack of regulatory protections 
on state lands, a limited proportion of the range of the Applegate 
salamander DPS, does not pose a threat to this genetic subunit in the 
foreseeable future.

Summary of Factor D

    Existing Federal regulations currently provide substantial 
protection on Federal lands for the Applegate salamander DPS through 
the NWFP land use categories and management provisions. For the 
purposes of this finding, we assume that the NWFP's Survey and Manage 
Program, which provides additional protection for the Applegate 
salamander DPS, is eliminated for future projects on Federal lands 
within the range of the DPS. Regulatory protection for this DPS will 
consist of the Standards and Guidelines of the NWFP, other Federal land 
management regulations, and the Special status Species programs, which 
will continue to provide adequate protection for the DPS across the 85 
percent of its range that occurs on Federal lands. While the 
petitioners have cited the proposed WOPR as posing a significant 
reduction to these protections (Greenwald and Curry 2007, p. 7), we 
cannot at this time speculate about what impact, if any, the proposal, 
if finalized in the future by BLM, may have on salamander populations 
or their habitat.
    We find that the current Federal regulations and land management 
planning guidelines and the Special status Species programs provide 
substantial protection for the DPS across the vast majority of its 
range. The lack of regulatory mechanisms to protect the Applegate 
salamander DPS on private lands in Oregon does not pose a substantial 
threat because: (1) Private lands comprise a small portion of the DPS's 
range and are distributed in small parcels interspersed among Federal 
lands where management is more favorable and therefore, acts to 
maintain redundancy, distribution, and connectivity among populations 
within the mix of Federal and private lands; and (2) salamander 
populations have been shown to persist in managed landscapes. While 
there is some uncertainty concerning the future of CESA protections for 
Applegate salamander DPS populations in California, the potential 
removal of CESA protections will not pose a significant threat to the 
DPS due to the very small percentage of the DPS's range that occurs in 
the state and the interspersed pattern of private and state

[[Page 4406]]

lands. We, therefore, conclude that the Applegate salamander DPS is not 
now, or in the foreseeable future, threatened by inadequate existing 
regulatory mechanisms across its range.

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

    Other natural or manmade factors that could potentially affect the 
persistence of the Applegate salamander DPS within all or significant 
portion of its range are climate changes associated with global warming 
and stochastic events, which are rare, chance events, such as epidemics 
and large, severe wildfires.

Climate Change

    The similarities in physiology, ecology, and habitat associations 
between the Applegate salamander DPS and other members of the Siskiyou 
Mountains salamander Complex, combined with the large scales at which 
climate change studies are conducted, lead us to conclude that our 
analysis of the potential effects of climate change under Factor E for 
the Siskiyou Mountains salamander applies to the Applegate DPS as well. 
Given its physiology, this species may be strongly affected by changes 
to precipitation patterns. Although most of the available climate 
models predict increases in average temperatures, models were 
inconsistent with regard to future precipitation; increases in annual 
precipitation and cloud cover are a plausible outcome and could act to 
ameliorate negative impacts caused by increased temperatures. We are 
unable to predict the potential effects of future climate change on the 
Applegate salamander DPS at this time.

Stochastic Events

    Like other members of the Siskiyou Mountains salamander Complex, 
the Applegate salamander DPS occupies a relatively small geographic 
range (248,870 ac (100,712 ha)) and exhibits limited dispersal 
abilities. These traits act to increase a species' vulnerability to 
stochastic (rare, chance) events such as epidemics or large, severe 
fires because a single event can occur within all or a large portion of 
the range, and individuals may be unable to escape the disturbance or 
recolonize habitat following extirpation. However, as described in the 
``Range and Distribution'' section and Factor A for the Siskiyou 
Mountains salamander, current research suggests that Applegate 
salamanders are in fact well-distributed within their range, that they 
occur at high densities in some areas, and that they persist in areas 
that have experienced disturbances. These traits act to decrease the 
potential vulnerability conferred on this DPS by its small range. While 
it may be reasonably expected that negative effects to abundance or 
population structure may follow severe disturbances (as described under 
Factor A for the Siskiyou Mountains salamander), there is no evidence 
that they result in significant losses of populations.
    A large wildfire that affects the majority of the range of the 
Applegate salamander DPS is a plausible description of a significant 
stochastic event. For example, 499,965 ac (202,329 ha) burned during 
the 2002 Biscuit Fire in southwestern Oregon and northwestern 
California. Approximately 44 percent of the area (219,985 ac (89,025 
ha)) was severely burned (USDA and USDI 2004). In comparison, the 
species range of the Applegate salamander DPS is 248,870 ac (100,712 
ha). Although there is evidence that fire size and intensity may have 
increased in the Klamath-Siskiyou region, large fires with mixed 
severity are characteristic of the natural disturbance regime (Odion et 
al. 2004, p. 933; Agee 1993, pp. 388-389) within which these 
salamanders have evolved. The mosaic pattern of fire effects, combined 
with the salamanders' ability to remain protected underground and 
persist during postfire vegetation recovery, indicates that the threat 
posed by this stochastic event is unlikely to result in large-scale 
extirpation of populations.

Summary of Factor E

    Because of the uncertain nature of climate change predictions, 
particularly predictions of future precipitation patterns, we are 
unable to evaluate the potential for climate change to impact Applegate 
salamander DPS populations in the future. We find that, although 
stochastic events such as large wildfires may occur within a large 
portion of this salamanders' restricted range, Applegate salamanders 
appear to persist following wildfires and other disturbances, to 
recover as vegetation is re-established following disturbance, and have 
adequate numbers of well-distributed populations throughout their range 
to allow for persistence and viability of this DPS. We, therefore, 
conclude that the Applegate salamander DPS is not now, or in the 
foreseeable future, threatened by the individual or cumulative effects 
of climate change or stochastic events such as epidemics or large, 
severe wildfires.

Finding

    We assessed the best available scientific and commercial 
information regarding threats faced by the Applegate salamander DPS. We 
have reviewed the petition, information available in our files, and 
information submitted to us following our 90-day petition finding (72 
FR 14750; March 29, 2007). We also consulted with recognized salamander 
experts and Federal land managers, and arranged for researchers to 
initiate field studies to assess the distribution of genetic entities 
within the salamander complex, and demographic response of these 
species to forest structure.
    We find little support for the petitioners' claim that the 
Applegate salamander DPS is threatened by habitat destruction caused by 
timber harvesting and wildfire, and that existing regulatory mechanisms 
are inadequate to protect the DPS. While the available information 
suggests that Applegate salamanders may be positively associated with 
older forest conditions, the majority of studies and available field 
data show the species occupying a wide range of forest conditions, 
including previously harvested areas. Recent research indicates that 
even in severely disturbed habitats, the salamanders persist and 
populations recover as vegetation is re-established over time. Less 
intensive disturbances such as forest thinning and mixed-effects 
wildfire appear to have minor or short-term impacts on salamander 
abundance. There is no reliable evidence that indicates loss of 
populations or curtailment of this DPS's range has occurred.
    We acknowledge that intensive timber harvesting practices such as 
clear-cutting may have short-term negative impacts on abundance and 
population structure of Applegate salamanders. The extent and magnitude 
of such practices, however, are severely limited by a number of 
regulatory mechanisms and other factors operating within the 
salamanders' range, as evidenced by the steep decline in timber harvest 
levels on Federal lands that constitute 85 percent of the DPS's range. 
Over the past 20 years, timber harvest levels, particularly of 
intensive harvest methods, on Federal lands within the range of the 
Applegate salamander have declined by over 90 percent. Levels of timber 
harvesting are higher on private lands, which constitute only 15 
percent of the DPS's range and occur as small parcels interspersed 
among Federal lands. Due to the small proportion of the range 
consisting of private lands, coupled with the ability of Applegate 
salamanders to persist in managed

[[Page 4407]]

landscapes, we conclude that management activities on private lands do 
not pose a substantial threat to this DPS.
    There are a number of existing regulatory mechanisms that provide 
protection for Applegate salamanders and their habitats. The system of 
land use allocations and Standards and Guidelines of the NWFP act to 
limit the amount and intensity of land management activities on Federal 
lands, as evidenced by the dramatic decline in timber harvest levels 
observed since the NWFP was implemented. The Survey and Manage 
Mitigation Measure Standards and Guidelines are one aspect of the NWFP 
that has provided protection specifically to occupied salamander 
locations. However, we anticipate the elimination of the Survey and 
Manage Guidelines within the range of the Applegate salamander DPS. 
Federal land management agencies have implemented a Conservation 
Strategy founded on the Survey and Management guidelines for this DPS, 
to help provide for well-distributed, viable populations of Applegate 
salamanders over the long term. The Conservation Strategy uses an 
approach similar to that required by the Survey and Manage Program for 
this DPS (i.e., identification of a network of high-priority salamander 
populations for protection and management). However, because of the 
limited nature of the threats addressed by the Conservation Strategy, 
we did not rely on it in determining whether listing the Applegate 
salamander DPS is warranted.
    The BLM's proposal to revise WOPR on 19 percent of the Applegate 
salamander DPS's range is in draft form and undergoing public review. 
We cannot reliably predict the outcome of this process or what effect, 
if any, any future changes to the WOPR might eventually have on 
salamanders or their habitat. The NWFP land-use allocations, other 
federal land management, and the special Status Species programs 
constitute existing regulatory mechanisms that currently provide 
substantial protection for the Applegate DPS and it habitat on Federal 
lands and are anticipated to continue to provide such protection in the 
foreseeable future. Should regulatory protections change in the future, 
the Service can consider such changes in the context of the degree and 
immediacy of potential threats to the Siskiyou Mountains salamander at 
that time.
    Populations of Applegate salamanders are well distributed, and 
abundance within populations can be high. There are 440 known locations 
for this DPS, and many areas supporting suitable habitat have not been 
surveyed. These population characteristics, combined with the species' 
apparent ability to persist and recover following habitat disturbance, 
indicates that Applegate salamanders are resilient to stochastic events 
such as wildfire. Our evaluation of climate change modeling for the 
geographic area inhabited by the salamanders does not support the 
contention that climate change poses a threat to Applegate salamanders. 
While increases in average daily temperatures are reliably predicted 
for the Klamath-Siskiyou region, predictions regarding timing and 
amount of precipitation are inconsistent, precluding any meaningful 
evaluation of future effects to these salamanders. It is not currently 
possible to forecast the specific effects of future climate on 
salamander populations.
    Our evaluation of the five listing factors does not support the 
contention that there are threats of sufficient imminence, intensity, 
or magnitude as to cause substantial threats to the DPS, losses of 
population distribution, or viability of the Applegate salamander DPS. 
Therefore, we do not find that the Applegate salamander DPS is in 
danger of extinction (endangered), nor is it likely to become 
endangered within the foreseeable future (threatened) throughout its 
range. Therefore listing the Applegate salamander DPS as threatened or 
endangered under the Act is not warranted at this time.

Grider Salamander Distinct Population Segment

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

    Our current knowledge of the habitat associations of the Grider 
salamander DPS, and the potential effects of habitat perturbations such 
as timber harvest and fire on this salamander, are based primarily on 
research conducted across the range of the entire Siskiyou Mountains 
salamander Complex. The members of the complex have similar 
physiological and behavioral characteristics, and consequently similar 
habitat associations. This conclusion is supported by Welsh et al. 
(2007a, p. 31), who state that the genetic subunits of Siskiyou 
Mountains salamander ``do little if anything to alter their basic eco-
physiological limits (e.g., Spotila 1972; Feder 1983) and consequent 
similar environmental requirements imposed by the plethodontid life 
form.'' We recognize that the range of the Grider salamander DPS is 
roughly 40 percent of the area occupied by the entire Siskiyou 
Mountains salamander, and that the relative magnitude of effects caused 
by habitat perturbations may be greater at this smaller spatial scale. 
We have incorporated these differences of scale into our analysis. 
Given this caveat, we believe that the potential effects of timber 
harvesting, fire, and other habitat perturbations on the Grider 
salamander DPS are similar to those described previously for the 
Siskiyou Mountains salamander. To avoid redundancy, these effects are 
summarized below; details and citations may be found in the Factor A 
analysis for Siskiyou Mountains salamander.

Effects of Timber Harvesting on the Grider Salamander DPS

    Although rigorous research of the effects of timber harvesting on 
Grider salamanders is lacking, the available evidence suggests that 
intensive timber harvest practices such as clear-cutting have a short-
term (30 years) negative impact on abundance, age structure, and body 
condition of these salamanders. However, it is also clear that the 
salamanders frequently persist in intensively harvested areas, and that 
populations recover as vegetation is re-established. Alternative timber 
harvesting methods such as thinning and helicopter yarding have not 
been shown to have negative effects on populations of this DPS.

Extent and Magnitude of Timber Harvesting Effects on the Grider 
Salamander DPS

    The extent and magnitude of potential effects caused by timber 
harvesting are strongly limited by existing land management regulations 
on the majority of the range of this DPS. Approximately 91 percent of 
the range of the Grider salamander DPS consists of Federal lands 
managed by the Klamath National Forest (KNF) under the provisions of 
the NWFP. Approximately 73 percent of the range occurs within reserves 
(Late-successional Reserves, Wilderness, Riparian Reserves) withdrawn 
from scheduled timber harvesting; an additional 13 percent of the range 
is within Matrix-retention areas where timber harvest is restricted. 
Less than 5 percent of the Grider salamanders' range lies within the 
Matrix-General Forest land allocation where intensive timber harvesting 
is anticipated to occur.
    Primarily as a result of implementation of the NWFP, the rate and 
intensity of timber harvesting has declined substantially on Federal 
lands within the range of the Grider salamander DPS. During the period 
from 1979 to 1984, the KNF sold and removed an average of 238.2 million

[[Page 4408]]

board feet of timber per year; harvest levels declined to 187.8 million 
board feet per year during 1985 to 1990, and fell to 15.9 million board 
feet annually between 2000 and 2005; a decrease of roughly 93 percent 
(USDA 2006a). The proportion of intensive timber management practices 
such as clear-cutting and overstory removal has declined even more 
abruptly; from an annual average of 3,733 ac (1,511 ha) per year from 
1988 to 1991 to roughly 38 ac (15.4 ha) per year during 2000 to 2006 
(USDA 2007b). We conclude that the land management regulations 
responsible for this long-term declining trend in the rate and 
intensity of timber harvesting greatly reduces the likelihood that a 
substantial proportion of the Grider salamander DPS will be negatively 
affected by intensive timber harvesting.
    Less than 10 percent of the Grider salamander's range consists of 
private timberlands where intensive timber harvesting practices such as 
clear-cutting and shelterwood removal are likely to occur. Virtually 
all of these lands are in California; only about 1 percent occurs in 
Oregon. The majority of private lands within the range of the Grider 
salamander DPS occur as small parcels (typically one square mile or 
less) in a checkerboard pattern surrounded by Federal lands. Salamander 
populations on private lands may be affected by timber harvesting but 
are dispersed among populations on Federal lands where management is 
more favorable and serves to effectively reduce the impacts of 
intensive private land timber harvest practices and maintain 
redundancy, distribution, and connectivity among Grider DPS 
populations.

Wildfire

    We assume that the potential effects of wildfire on the Grider 
salamander DPS are similar to those described under Factor A for the 
Siskiyou Mountains salamander. It is likely that intense, stand-
replacing fires reduce habitat quality for this salamander by reducing 
overstory cover and consuming moss, duff and forest floor litter; 
affecting the microclimate conditions. However, Siskiyou Mountains 
salamanders appear to be behaviorally adapted to dry-season fires 
because they are underground during summer and fall when most wildfires 
occur. While it is likely that large-scale intense wildfires may 
negatively impact some populations, at least in the short term, 
populations appear to persist and recover as vegetation is re-
established after severe habitat disturbances. Fire regimes within the 
Klamath-Siskiyou region are characterized by mixed-severity fires that 
burn in a range of intensities, resulting in a mosaic of habitat 
effects. Fire effects are frequently moderated on lower slopes with 
northerly exposures and topographic conditions frequently associated 
with salamander locations.

Direct Disturbance: Roads and Road Construction, Mining, and Rock 
Quarrying

    We assume that the effects of activities that physically alter the 
talus substrates occupied by Grider salamanders are similar to those 
described under Factor A for the Siskiyou Mountains salamander. 
Although research to evaluate salamander response to physical 
disturbance is lacking, it is reasonable to assume that these 
activities likely reduce habitat quality or remove habitat. In 
addition, some research suggests that forest roads may pose a barrier 
to these salamanders, reducing dispersal and connectivity among 
populations. We find that, while it may reasonably be expected that 
crushing or removal of talus habitat during road construction, mining, 
or rock quarrying could negatively affect Grider salamander 
populations, these activities affect a very small area of the DPS 
range. For this reason, Olson et al. (2007, p. 17) conclude that these 
disturbances do not pose a primary threat to the species. Numerous 
records exist of the salamanders occupying road cuts and sites with 
historical mining activity, suggesting that these disturbances do not 
eliminate populations. The rate of road construction, which is 
typically associated with access for timber harvesting, has declined 
significantly as timber harvest levels have dropped. Surface mining 
rarely occurs within the range of the DPS, and rock quarrying consists 
of a small number of sites encompassing an insignificant proportion of 
the range (less than 100 ac (40.5 ha)).

Summary of Factor A

    We find that, while the abundance and population structure of 
Grider salamanders appear to suffer short-term negative effects from 
intensive timber management practices such as clear-cutting, these 
practices are severely restricted on Federal lands, which constitute 
over 90 percent of the DPS's range. Less than five percent of the 
Grider salamander's range lies within the Matrix-General Forest land 
allocation where intensive timber harvesting is anticipated to occur. 
Less intensive harvest practices appear to have relatively minor or 
short-term impacts to salamander abundance, and the available evidence 
suggests that salamander populations persist in a broad range of forest 
habitat conditions and under different management practices.
    The system of NWFP reserves and management guidelines in effect on 
Federal lands, in combination with other Federal land management 
direction and the Special Status Species programs, provide substantial 
protection for Grider salamander habitat, dramatically reducing the 
likelihood of large-scale reduction of suitable or occupied habitat due 
to timber harvesting. Even without Survey and Manage protections, the 
available evidence does not show that timber harvest practices on 
Federal lands, either alone or in combination with other habitat 
disturbing activities such as mining, road building or wildfire, have 
reduced the habitat or range of this species or are likely to do so in 
the foreseeable future.
    Management practices on private timberlands may negatively affect 
some populations of the Grider salamander DPS; however, due to the 
patchy distribution of private lands within the larger matrix of 
Federal lands, and the ability of these salamanders to persist in 
managed habitats, we conclude that habitat modifications on this small 
portion of the Grider salamander DPS's range do not constitute a 
substantial threat to the DPS.
    Wildfires are a naturally occurring disturbance factor in the 
Klamath-Siskiyou region, and are expected to influence the abundance 
and distribution of salamander habitats. However, the effects of most 
wildfires on salamander habitat are temporary and populations appear to 
recover as vegetation recovers. Wildfires typically burn in a mosaic 
pattern of intensities, leaving a variety of habitat conditions for 
salamanders within burned areas.
    Grider salamander populations have been shown to exist in a range 
of habitat conditions that have experienced timber harvesting, 
wildfire, and other disturbances, and there is little evidence to 
suggest that populations are extirpated followed the land management 
activities such as thinning and salvage harvesting typically employed 
on KNF lands. Intense disturbances such as clear-cutting are highly 
limited by current land-use regulations, and along with rock quarrying 
and road construction constitute a tiny fraction of the DPS's habitat. 
Therefore, we conclude that the Grider salamander DPS is not now, or in 
the foreseeable future, threatened by

[[Page 4409]]

destruction, modification, or curtailment across its range.

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

    We are not aware of any information that indicates overutilization 
for commercial, recreational, scientific, or educational purposes 
threatens, now or in the foreseeable future, the Grider salamander DPS 
across its range.

Factor C: Disease or Predation

    Chytridiomycosis is a relatively recently described epidermal 
infection of amphibians caused by the chytrid fungus Batrachochytrium 
dendrobatidis. This fungus requires moisture for survival (Johnson and 
Speare 2003, p. 922) and is therefore more likely to pose a threat to 
aquatic amphibians than to terrestrial ones. As described for the 
Siskiyou Mountains salamander, we do not anticipate that the Grider 
salamander DPS will be exposed to this disease or that exposure would 
lead to transmission through significant portions of its range. This 
DPS is not associated with bodies of water, occurs in a 
characteristically dry environment, is only active above ground for 
brief and intermittent periods during the year, and appears to have 
limited dispersal abilities. Given these restrictions, we believe that 
the Grider salamander DPS is unlikely to be exposed to diseased water 
or infected aquatic amphibians and, if infected, these salamanders are 
unlikely to transmit the disease between populations.
    The Service is not aware of any predators that potentially pose a 
threat to the species. We therefore conclude that the Grider salamander 
DPS is not now, or in the foreseeable future, threatened by disease or 
predation across its range.

Factor D: Inadequacy of Existing Regulatory Mechanisms

Federal Lands

    Existing Federal regulations currently provide substantial 
protection on Federal lands for the Grider salamander DPS through the 
NWFP land use allocations and their management provisions. The NWFP 
management provisions and current status of the Survey and Manage 
Program are described under Factor D for the Siskiyou Mountains 
salamander. The Survey and Manage Program contains specific guidance 
for the Grider salamander DPS, requiring surveys of potentially 
suitable talus habitat and restricting management activities at 
occupied salamander locations. For purposes of this finding, we assume 
that NWFP's Survey and Manage Program is eliminated for future projects 
on Federal lands within the range of the DPS.
    Given the high proportion of KNF lands in reserved land allocations 
(86 percent), the low rate of timber harvest, and the low intensity of 
harvest practices typically employed by the KNF, we conclude that the 
removal of Survey and Manage guidelines does not pose a substantial 
threat to the species. Management of the Grider salamander DPS will be 
conducted under the USFS's Sensitive Species Program, which does not 
specify protections, but contains provisions for development of 
conservation strategies that are anticipated to provide an additional 
layer of security for the DPS.

Private Lands and State Regulations

    The Siskiyou Mountains salamander is listed as a threatened species 
in California and receives substantial protections pursuant to CESA. 
These protections include the requirement of surveys prior to project 
implementation and prohibitions on timber harvest in established 
buffers around occupied suitable habitat (see Factor D for Siskiyou 
Mountains salamander). The future of CESA protections for Grider 
salamander populations on private timberlands is uncertain. However, 
any future changes in the status of CESA protections for the Grider 
salamander DPS would affect only nine percent of the range of the 
Grider salamander DPS, and this area consists of small parcels 
interspersed among Federal lands. This, combined with evidence that 
Grider salamander populations persist in disturbed habitats, suggests 
that the removal of CESA protections will not pose a substantial threat 
to the species.

Summary of Factor D

    The Grider salamander DPS receives substantial protection based on 
the land allocations and Standards and Guidelines of the NWFP and KNF 
Land and Resource Management Plan. Future protection of the Grider 
salamander DPS will also occur through the USFS Sensitive Species 
Program. The high proportion the DPS's range within reserved land 
allocations, combined with the overall low rate and intensity of timber 
harvest on Federal lands leads us to conclude that elimination of the 
Survey and Manage guidelines does not pose a substantial threat to this 
DPS. We find that the combination of Federal regulations and land 
management planning guidelines provide adequate existing regulatory 
mechanisms across the vast majority of the DPS's range.
    The Grider salamander DPS also receives protection on private lands 
in California under CESA. The uncertainty of future CESA protections 
for Grider salamander populations on private lands does not pose a 
substantial threat to the DPS because: (1) Private lands comprise a 
small portion of the DPS's range and generally consist of small parcels 
interspersed among Federal lands; and (2) salamander populations have 
been shown to persist in managed landscapes. We therefore conclude that 
the Grider salamander DPS is not now, or in the foreseeable future, 
threatened by inadequate existing regulatory mechanisms.

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

    Other natural or manmade factors that may affect the persistence of 
the Grider salamander DPS within all or significant portion of its 
range are climate changes associated with global warming and stochastic 
events, which are rare, chance events, such as epidemics and large, 
severe wildfires.

Climate Change

    Because the physiology, ecology, and habitat associations of the 
Grider salamander DPS are similar to other members of the Siskiyou 
Mountains salamander Complex, we conclude that our analysis of the 
potential effects of climate change and stochastic events under Factor 
E for the Siskiyou Mountains salamander applies to the Grider 
salamander DPS as well. Most of the climate change models available for 
the Pacific Northwest predicted increases in average temperatures; 
however, models were inconsistent with regard to future precipitation. 
Some models predicted significant increases in annual precipitation and 
cloud cover, which could act to ameliorate any negative impacts caused 
by increased temperatures. Given the inconsistency of climate change 
predictions available to us, we are unable to predict the potential 
effects of future climate change on the Grider salamander DPS at this 
time.

Stochastic Events

    The relatively small geographic range (174,285 ac (70,529 ha)) and 
limited dispersal abilities of the Grider salamander DPS may increase 
its vulnerability to stochastic (rare, chance) events such as epidemics 
or large, severe fires because a single event can occur within all or a 
large portion of the range, and individuals may be unable to escape the 
disturbance or recolonize habitat following extirpation. The

[[Page 4410]]

petitioners claim that these salamanders are rare, patchily 
distributed, and easily extirpated by disturbances, making them highly 
vulnerable to extinction (Greenwald and Curry 2007, p. 1). However, as 
described under ``Range and Distribution'' and Factor A for the 
Siskiyou Mountains salamander, current research suggests that Grider 
salamanders are in fact well-distributed within their range, that they 
occur at high densities in some areas, and that they persist in areas 
that have experienced disturbances. These traits act to decrease the 
potential vulnerability conferred on this DPS by its small range. While 
it may be reasonably expected that negative effects to abundance or 
population structure may follow severe disturbances (as described under 
Factor A for the Siskiyou Mountains salamander), there is no evidence 
that they result in significant losses of populations.
    A large wildfire that affects the majority of the range of the 
Grider salamander DPS is a plausible description of a significant 
stochastic event. For example, 499,965 ac (202,329 ha) burned during 
the 2002 Biscuit Fire in southwestern Oregon and northwestern 
California. Approximately 44 percent of the area (219,985 ac (89,025 
ha)) was severely burned (USDA and USDI 2004). In comparison, the 
species range of the Grider salamander is 174,285 ac (70,529 ha). 
Although there is evidence that fire size and intensity may have 
increased in the Klamath-Siskiyou region, large fires with mixed 
severity are characteristic of the natural disturbance regime (Odion et 
al. 2004, p. 933; Agee 1993, pp. 388-389) within which these 
salamanders have evolved. The mosaic pattern of fire effects, combined 
with the salamanders' ability to remain protected underground and 
persist during postfire vegetation recovery, indicates that the threat 
posed by this stochastic event is unlikely to result in large-scale 
extirpation of populations.

Summary of Factor E

    Because of the uncertain nature of climate change predictions, 
particularly predictions of future precipitation patterns, we are 
unable to evaluate the potential for climate change to impact Grider 
salamander populations in the foreseeable future. We find that, 
although stochastic events such as large wildfires may occur within a 
large portion of this salamanders' restricted range, Grider salamanders 
appear to persist following wildfires and other disturbances, to 
recover as vegetation is re-established following disturbance, and have 
adequate numbers of well-distributed populations throughout their range 
to allow for persistence and viability of this DPS. We therefore 
conclude that the Grider salamander DPS is not now, or in the 
foreseeable future, threatened by the individual or cumulative effects 
of climate change or stochastic events such as epidemics or large, 
severe wildfires.

Finding

    We assessed the best available scientific and commercial 
information regarding threats faced by the Grider salamander DPS. We 
have reviewed the petition, information available in our files, and 
information submitted to us following our 90-day petition finding (72 
FR 14750; March 29, 2007). We also consulted with recognized salamander 
experts and Federal land managers, and arranged for researchers to 
initiate field studies to assess the distribution of genetic entities 
within the salamander complex, and demographic response of these 
species to forest structure.
    We find little support for the petitioners' claim that the Grider 
salamander DPS is threatened by habitat destruction caused by timber 
harvesting and wildfire, and that existing regulatory mechanisms are 
inadequate to protect the DPS from this habitat loss. While the 
available information suggests that Grider salamanders may be 
positively associated with older forest conditions, the majority of 
studies and available field data show the species occupying a wide 
range of forest conditions, including previously harvested areas. 
Recent research indicates that even in severely disturbed habitats, the 
salamanders persist and populations recover as vegetation is re-
established over time. Less intensive disturbances such as forest 
thinning and mixed-effects wildfire appear to have minor or short-term 
impacts on salamander abundance. There is no reliable evidence that 
indicates that loss of populations or curtailment of this DPS's range 
has occurred.
    We acknowledge that intensive timber harvesting practices such as 
clear-cutting may have short-term negative impacts on abundance and 
population structure of Grider salamanders. The extent and magnitude of 
such practices, however, are severely limited by a number of regulatory 
mechanisms and other factors operating within the salamanders' range, 
as evidenced by the steep decline in timber harvest levels on Federal 
lands that constitute 91 percent of the DPS' range. Over the past 20 
years, timber harvest levels, particularly of intensive harvest 
methods, on Federal lands within the range of the Grider salamander 
have declined by over 93 percent. Levels of timber harvesting are 
higher on private lands, which constitute only nine percent of the 
DPS's range and occur as small parcels interspersed among Federal 
lands. Due to the small proportion of the DPS's range that consists of 
private lands, the scattered small size of private land parcels, and 
the ability of Grider salamanders to persist in managed landscapes, we 
conclude that management activities on private lands do not pose a 
substantial threat to this DPS.
    There are a number of existing regulatory mechanisms that provide 
protection for the Grider salamanders and its habitat. The system of 
land use allocations under the NWFP act to limit the amount and 
intensity of land management activities on Federal lands, as evidenced 
by the dramatic decline in timber harvest levels observed since the 
NWFP was implemented. The Survey and Manage Mitigation Measure 
Standards and Guidelines are one aspect of the NWFP that, in the past, 
has provided protection specifically to occupied salamander locations. 
While the Survey and Manage Program has been eliminated for future 
projects on Federal lands, we find that existing land management 
regulations are adequate given the low degree of threat posed by land 
management activities.
    Populations of Grider salamanders are well distributed, and 
abundance within populations can be high. There are 76 known locations 
for this DPS, and many areas supporting suitable habitat have not been 
surveyed. These population characteristics, combined with the species' 
apparent ability to persist and recover following habitat disturbance, 
indicates that Grider salamanders are resilient to stochastic events 
such as wildfire. Our evaluation of climate change modeling for the 
geographic area inhabited by the salamanders does not support the 
contention that climate change poses a threat to Grider salamanders. 
While increases in average daily temperatures are reliably predicted 
for the Klamath-Siskiyou region, predictions regarding timing and 
amount of precipitation are inconsistent, precluding any meaningful 
evaluation of future effects to these salamanders. It is not currently 
possible to forecast the specific effects of future climate on 
salamander populations.
    Our evaluation of the five listing factors does not support the 
contention that there are threats of sufficient imminence, intensity, 
or magnitude as to cause substantial losses of population distribution 
or viability of the Grider salamander DPS. Therefore, we do not

[[Page 4411]]

find that the Grider salamander DPS is in danger of extinction 
(endangered), nor is it likely to become endangered within the 
foreseeable future (threatened) throughout its range. Therefore listing 
the Grider salamander DPS as threatened or endangered under the Act is 
not warranted at this time.

Scott Bar Salamander

Summary of Factors Affecting the Species

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

    The Service believes that the potential effects of habitat 
perturbations such as timber harvest and fire on the Scott Bar 
salamander are the same as those previously described for the entire 
Siskiyou Mountains salamander Complex. This conclusion is based on: (1) 
Our understanding of the behavior, physiology, and habitat associations 
of the Scott Bar salamander based primarily on research conducted 
across the range of the entire Siskiyou Mountains salamander Complex; 
and (2) available information which indicates that members of the 
complex have similar physiological and behavioral characteristics, and 
consequently similar habitat associations (Welsh et al. 2007a, p. 31). 
Because the range of the Scott Bar salamander is roughly 32 percent of 
the area occupied by the Siskiyou Mountains salamander, the relative 
magnitude of effects caused by habitat perturbations may be greater at 
this smaller spatial scale. Despite differences in scale, we believe 
that the potential effects of timber harvesting, fire, and other 
habitat perturbations on the Scott Bar salamander are the same as those 
described previously for the Siskiyou Mountains salamander. To avoid 
redundancy, these effects are summarized below; further detail and 
citations may be found in the Factor A analysis for Siskiyou Mountains 
salamander.

Effects of Timber Harvesting on the Scott Bar Salamander

    Our evaluation of recent research results and survey information 
indicates that, while abundance of Scott Bar salamanders may be greater 
at sites with dense, mature forest cover, this species also occupies a 
wide range of forest age and density conditions. Intensive timber 
harvesting practices such as clear-cutting likely have negative effects 
on habitat quality and subsequent abundance and population structure of 
salamanders. However, recent research suggests that Scott Bar 
salamanders persist in disturbed sites and their populations recover as 
vegetation is re-established and habitat conditions improve (Welsh et 
al. 2007b).
    Roughly 40 percent of known Scott Bar salamander locations occur on 
private timberlands where intensive timber management has been 
conducted for decades. Farber (2007a, p. 3) evaluated population 
structure and habitat characteristics at all Scott Bar salamander sites 
known to be occupied on and adjacent to Timber Products Company (TPC) 
lands. Ninety-four percent of the sites exhibited evidence of at least 
one habitat disturbance such as roads, logging activity, wildfire, and 
mining; 53 percent had evidence of recent or historic timber harvest. 
None of the salamander sites were in old-growth or late-seral habitat; 
all were in relatively young forests and over 50 percent occurred in 
stands with open canopies. At 26 sites on TPC lands where a minimum of 
two surveys were conducted, 96 percent supported adult salamanders, and 
65 percent exhibited all life stages (adults, subadults, and 
juveniles); gravid females were detected at 54 percent of sites. While 
these results cannot be inferred to the entire species' range, they 
clearly suggest that Scott Bar salamander populations persist and 
appear to be viable within the range of habitat conditions found on 
managed timberlands.

Extent and Magnitude of Timber Harvesting Effects on the Scott Bar 
Salamander

    Existing land management regulations place substantial limits on 
the extent and magnitude of potential effects caused by timber 
harvesting on populations of Scott Bar salamanders. Approximately 78 
percent of the Scott Bar salamanders' range consists of Federal lands 
managed by the KNF under the provisions of the NWFP. Approximately 51 
percent of the range occurs within reserves (Late-successional 
Reserves, Wilderness, and Riparian Reserves) withdrawn from scheduled 
timber harvesting; an additional 19 percent of the range is within 
Matrix-Retention areas where timber harvest is restricted. Only about 
eight percent of the Scott Bar salamanders' range lies within the 
Matrix-General Forest land allocation where intensive timber harvesting 
is anticipated to occur.
    The rate and intensity of timber harvesting has declined 
substantially on Federal lands within the range of the Scott Bar 
salamander, primarily due to NWFP provisions. The amount of timber sold 
and removed on the Klamath National Forest declined by roughly 93 
percent between 1984 and 2005, from an average of 238.2 million board 
feet of timber per year in 1979 to 1984, to 15.9 million board feet 
annually between 2000 and 2005 (USDA 2006a). The proportion of 
intensive timber management practices such as clear-cutting and 
overstory removal has also declined sharply, from an annual average of 
3,733 ac (1,511 ha) per year from 1988 to 1991, to roughly 38 ac (15.4 
ha) per year during 2000 to 2006 (USDA 2007b). We conclude that the 
land management regulations responsible for this long-term declining 
trend in the rate and intensity of timber harvesting greatly reduces 
the likelihood that a substantial proportion of the Scott Bar 
salamander will be affected by intensive timber harvesting.
    Private timberlands comprise 22 percent of the range of the Scott 
Bar salamander. State of California regulations under the California 
Endangered Species Act currently protect Scott Bar salamanders on 
private lands by requiring surveys and prohibiting habitat modification 
at occupied sites, timber harvesting, and other habitat disturbances.
    Private timberlands within the range of the Scott Bar salamander 
occur as small (one square mile) parcels distributed in a checkerboard 
pattern surrounded by KNF lands. This pattern acts to maintain the 
distribution of, and connectivity among, salamander populations at 
larger spatial scales, subsequently reducing the overall impact of 
habitat losses on private lands. Salamander populations occupying the 
private portions of this landscape pattern may experience fluctuations 
in the amount or quality of habitat through time but likely receive 
demographic support from adjacent populations on Federal lands where 
management is more favorable.
    Although the rate and intensity of timber harvest is greater on 
privately owned timberlands within the range of the Scott Bar 
salamander, not all private lands are expected to receive intensive 
treatments. Timber Products Company, the primary industrial landowner 
within the species' range, estimates that roughly 31 percent of the 
company's land base within the range of the Scott Bar salamander in 
Siskiyou County consists of land unsuitable for harvest (e.g., montane 
hardwoods, watercourse protection zones, rock outcrops). On the 
remaining 69 percent, 31 percent of projected timber harvest 
prescriptions consist of less-intensive harvest prescriptions such as 
thinning and selection, and 69 percent are more intensive treatments 
such as clear-cut, shelterwood removal, and seed tree

[[Page 4412]]

harvest (Farber 2007c); suggesting that about 50 percent of TPC lands 
are anticipated to receive intensive harvesting. Of the 25 Scott Bar 
salamander locations currently known on TPC lands, 4 (16 percent) occur 
in riparian areas where timber harvest is restricted by State 
regulations, and 7 (28 percent) are located in previously harvested 
areas where additional timber harvesting is not anticipated over the 
next 20 to 30 years (Farber 2007b, pp. 1-2). This information, combined 
with data indicating that salamander populations persist within managed 
timberlands, further suggests that even in the absence of State 
protections for this species, intensive timber harvest would not be 
expected to impact a majority of populations within the 22 percent of 
the species' range that occurs on private lands or pose a substantial 
threat to the species.

Wildfire

    Based on the best scientific information available, we believe the 
potential effects of wildfire on the Scott Bar salamander are similar 
to those described previously for the Siskiyou Mountains salamander. 
Fire regimes within the Klamath-Siskiyou region are characterized by 
mixed-severity fires that burn in a range of intensities, resulting in 
a mosaic of habitat effects at both fine and landscape-level spatial 
scales. Fire effects are frequently moderated on lower slopes with 
northerly exposures, topographic conditions frequently associated with 
salamander locations. Intense, stand-replacing fires likely reduce 
habitat quality for these salamanders by reducing overstory cover and 
consuming moss, duff, and forest floor litter, thereby modifying the 
microclimate conditions. It is likely that large-scale intense 
wildfires may negatively affect some populations, at least in the short 
term, but the degree to which more typical mixed-severity wildfires 
affect the viability of salamander populations is unknown. However, 
Scott Bar salamanders appear to be behaviorally adapted to dry-season 
fires because they are underground during summer and fall when most 
wildfires occur. Populations appear to persist and recover as 
vegetation is re-established after severe habitat disturbances (Bull et 
al. 2006, p. 24; Welsh et al. 2007b).

Direct Disturbance: Roads and Road Construction, Mining, and Rock 
Quarrying

    As described under Factor A for the Siskiyou Mountains salamander, 
activities that physically alter the talus substrates occupied by the 
Scott Bar salamander have the potential to reduce habitat quality or 
remove habitat. While some of these activities such as rock quarrying 
may completely remove habitat, evidence suggests that salamander 
populations continue to occupy areas that show evidence of previous 
mining and road construction. In particular, numerous Scott Bar 
salamander locations occur in road cuts where rock substrate has been 
exposed. Although the ease of accessing and surveying such sites may 
influence the probability of detecting salamanders, the frequent 
presence of salamanders in road cuts suggests that this species can 
persist in or recolonize disturbed substrates. Despite these potential 
effects, road construction and rock quarrying are extremely limited in 
spatial extent, affecting a very small fraction of the salamander's 
range, and are not considered a substantial threat to these salamanders 
(Olson et al. 2007, p. 17).

Summary of Factor A

    The abundance and population structure of Scott Bar salamanders 
appear to exhibit short-term negative effects from intensive timber 
management practices such as clear-cutting, but these practices are 
severely restricted on Federal lands, which constitute 78 percent of 
the species' range. Less intensive harvest practices appear to have 
relatively minor or short-term impacts to salamander abundance, and the 
available evidence suggests that salamander populations persist in a 
broad range of forest habitat conditions and under different management 
practices.
    Scott Bar salamander populations receive substantial protection 
from the system of NWFP reserves and management guidelines in effect on 
Federal lands, in combination with other land management direction 
(e.g. Roadless Areas, retention areas) and the Special Status Species 
programs, dramatically reducing the likelihood of substantial negative 
impacts to suitable or occupied habitat due to timber harvesting. Even 
without Survey and Manage protections, the available evidence does not 
show that timber harvest practices on Federal lands, either alone or in 
combination with other habitat disturbing activities such as mining, 
road building or wildfire, have reduced the habitat or range of this 
species or are likely to do so in the foreseeable future.
    Although timber harvest levels on private timberlands are greater 
than on Federal lands, current State regulations restrict management 
activities at occupied Scott Bar salamander locations. Known salamander 
locations on private timberlands occur in a variety of habitat 
conditions, including previously harvested areas and naturally open 
sites, demonstrating that populations persist in these managed 
landscapes. The dispersed pattern of private land parcels among Federal 
lands acts to maintain well-distributed populations, and may allow 
demographic support between adjacent populations.
    Wildfires are a naturally-occurring disturbance factor in the 
Klamath-Siskiyou region, and are expected to influence the quality, 
abundance and distribution of Scott Bar salamander habitat. However, 
the effects of most wildfires on salamander habitat appear to be 
temporary and populations recover as vegetation is re-established on 
burned areas. Wildfires typically burn in a mosaic pattern of 
intensities, leaving a variety of habitat conditions for salamanders 
within burned areas.
    In summary, Scott Bar salamander populations have been shown to 
exist in a range of habitat conditions that have experienced timber 
harvesting, wildfire, and other disturbances, and there is evidence 
suggesting that populations persist and recover following habitat 
disturbances. Current land-use regulations, including State regulations 
protecting the Scott Bar salamander on private timberlands, strongly 
limit intense disturbances such as clear-cutting, rock quarrying, and 
road construction. Therefore, we conclude that the Scott Bar salamander 
is not now, or in the foreseeable future, threatened by destruction, 
modification, or curtailment across its range.

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

    We are not aware of any information that indicates overutilization 
for commercial, recreational, scientific, or educational purposes 
threatens the Scott Bar salamander, now or in the foreseeable future, 
across its range.

Factor C: Disease or Predation

    Chytridiomycosis is a relatively recently described epidermal 
infection of amphibians caused by the chytrid fungus Batrachochytrium 
dendrobatidis. This fungus requires moisture for survival (Johnson and 
Speare 2003, p. 922) and is therefore more likely to pose a threat to 
aquatic amphibians than to terrestrial ones. As described for the 
Siskiyou Mountains salamander, we do not anticipate that the Scott Bar 
salamander will be exposed to this disease or that exposure would lead 
to

[[Page 4413]]

transmission through significant portions of its range. This species is 
not associated with bodies of water, occurs in a characteristically dry 
environment, is only active above ground for brief and intermittent 
periods during the year, and appears to have limited dispersal 
abilities. Given these restrictions, we believe that the Scott Bar 
salamander is unlikely to be exposed to diseased water or infected 
aquatic amphibians and, if infected, is unlikely to transmit the 
disease between populations.
    The Service is not aware of any predators that potentially pose a 
threat to the species. We therefore conclude that the Scott Bar 
salamander is not now, or in the foreseeable future, threatened by 
disease or predation across its range.

Factor D: Inadequacy of Existing Regulatory Mechanisms

Federal Lands

    Existing Federal regulations currently provide substantial 
protection on Federal lands for the Scott Bar salamander through the 
NWFP land use allocations and their management requirements. The 
provisions and current status of the Survey and Manage Program are 
described under Factor D for the Siskiyou Mountains salamander. The KNF 
extended Survey and Manage Program guidance to the Scott Bar 
salamander, since this species cannot be easily distinguished from the 
Siskiyou Mountains salamander in the field (USDA 2006b, p. 2).
    The Survey and Manage Program requires surveys of potentially 
suitable talus habitat and restricting management activities at 
occupied Scott Bar salamander sites. For purposes of this finding, we 
assume that NWFP's Survey and Manage Program is eliminated for future 
projects on Federal lands within the range of the Scott Bar salamander.
    Given the high proportion of the species range in reserved land 
allocations (70 percent), the low rate of timber harvest, and the low 
intensity of harvest practices typically employed by the KNF, we 
conclude that the removal of Survey and Manage guidelines will not 
constitute a substantial threat to the species. Management of the Scott 
Bar salamander will be conducted under the USFS's Sensitive Species 
Program, which does not specify protections for the Scott Bar 
salamander but contains provisions for development of conservation 
strategies that are anticipated to provide an additional layer of 
security for the species.
    The low proportion of KNF lands in land allocations where intensive 
timber harvest is anticipated to occur (8 percent), combined with the 
low degree and immediacy of potential threats to the Scott Bar 
salamander, lead us to conclude that existing regulatory mechanisms are 
adequate to maintain the viability of the Scott Bar salamander on 
Federal lands throughout the species' range.

Private Lands and State Regulations

    In July 2005, CDFG described the Scott Bar salamander as a ``newly 
discovered species from what was part of the range of Plethodon 
stormi'' (CDFG 2005, p. 31). Based on this change of taxonomic status, 
CDFG took the position that the Siskiyou Mountains salamander 
populations now recognized as Scott Bar salamanders were no longer 
protected under CESA. That position was successfully challenged by 
three environmental organizations in state court (Environmental 
Protection Information Center v. California Department of Fish and 
Game, (No. CPF-06-506585)). The court concluded that, ``[b]y virtue of 
its having been accorded protection as a subgroup of a listed, 
protected species, the Scott Bar salamander's protection under the 
California Endangered Species Act cannot be withdrawn by the California 
Department of Fish and Game without action first being taken by the 
California Fish and Game Commission.'' On October 3, 2006, the 
California Fish and Game Commission received a petition to list the 
Scott Bar salamander under CESA. The Commission rejected the petition 
due to the protections already provided the species under CESA.
    The Scott Bar salamander is recognized by the Commission as 
protected under CESA as a sub-group or sub-population of the listed 
Siskiyou Mountains salamander (Cal. Code Regs. tit. 14, Sec.  670.5, 
subd. (b)(3)(A).). However, the California Office of Administrative Law 
recently rejected for procedural reasons a formal effort by the 
Commission to recognize the protected status of the Scott Bar 
salamander under CESA in State regulations (Cal. Reg. Notice Register 
2007, No. 28-Z, p. 1191). The Scott Bar salamander, therefore, is not 
specifically listed under CESA, but retains the same protections 
afforded the Siskiyou Mountains salamander. The Service is not aware of 
any other formal action by the Commission to recognize the protected 
status of Scott Bar salamander under CESA.
    The CDFG petition to delist the Siskiyou Mountains salamander does 
not include the historic portion of this species' range known to be 
occupied by the Scott Bar salamander. Therefore, the Service believes 
that regardless of the California Fish and Game Commission's decision 
on whether to delist the Siskiyou Mountains salamander, current State 
protections for the Scott Bar salamander will remain in effect until a 
formal rule-making process to remove these protections is undertaken. 
To our knowledge, there is no formal process currently underway to 
remove protections for the Scott Bar salamander.
    We recognize the uncertainty surrounding the future of State 
protections for Scott Bar salamanders on private lands and have 
evaluated the threat potentially posed by timber harvesting on private 
lands if protections were absent. As described under Factor A, we find 
that there is little evidence to suggest that timber harvesting on 
private lands threatens Scott Bar salamander populations because: (1) 
Numerous populations are currently known to occur in a variety of 
managed habitat conditions on private timberlands; (2) research 
indicates that populations of these salamanders persist following 
intensive timber harvest and recover as vegetation is re-established, 
and less intensive harvest practices appear to have minor or short-term 
effects on salamander abundance; and (3) private lands constitute only 
22 percent of the species' range, and are distributed in a dispersed 
pattern among Federal lands where conditions are more favorable and 
thus acts to maintain the distribution of, and connectivity among, 
salamander populations at larger spatial scales and reduce the impacts 
of intensive timber harvest on adjacent private lands. Therefore, we 
find that in the event that State protections for the Scott Bar 
salamander are removed, the lack of regulatory protections on private 
lands would not pose a substantial threat to this species in the 
foreseeable future.

Summary of Factor D

    The Scott Bar salamander receives substantial protection based on 
the land allocations and Standards and Guidelines of the NWFP and KNF 
Land and Resource Management Plan. Future protection of the Scott Bar 
salamander will likely also occur through the USFS Sensitive Species 
Program. The high proportion the species' range within reserved land 
allocations, combined with the overall low rate and intensity of timber 
harvest on Federal lands leads us to conclude that elimination of the 
Survey and Manage guidelines does not pose a substantial threat to this 
species. We find that the combination of Federal regulations and land 
management planning guidelines provide adequate

[[Page 4414]]

existing regulatory mechanisms across the vast majority of the species' 
range.
    The Scott Bar salamander also receives protection on private lands 
in California under CESA. While there presently is no effort underway 
to remove State protections for the Scott Bar salamander, the continued 
protection of the species under CESA for the foreseeable future is not 
certain. However, we find that the uncertain future of CESA protections 
for Scott Bar salamander populations on private lands does not pose a 
substantial threat because: (1) Private lands comprise a small portion 
of the species' range and are distributed in small parcels interspersed 
among Federal lands; and (2) salamander populations have been shown to 
persist in managed landscapes. We therefore conclude that the Scott Bar 
salamander is not now, or in the foreseeable future, threatened by 
inadequate regulatory mechanisms.

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

    Other natural or manmade factors that may affect the persistence of 
the Scott Bar salamander across its range are climate changes 
associated with global warming and stochastic events, which are rare, 
chance events such as epidemics and large, severe wildfires.

Climate Change

    The similarities in physiology, ecology, and habitat associations 
between the Scott Bar salamander and other members of the Siskiyou 
Mountains salamander Complex, combined with the large scales at which 
climate change studies are conducted, lead us to conclude that our 
analysis of the potential effects of climate change under Factor E for 
the Siskiyou Mountains salamander applies to the Scott Bar salamander 
as well. Given its physiology, this species may be strongly affected by 
changes to precipitation patterns. Although most of the available 
climate models predict increases in average temperatures, models were 
inconsistent with regard to future precipitation; increases in annual 
precipitation and cloud cover are a plausible outcome and could act to 
ameliorate any negative impacts caused by increased temperatures. We 
are unable to predict the potential effects of future climate change on 
the Scott Bar salamander at this time.

Stochastic Events

    The Scott Bar salamander is an endemic species with a relatively 
small geographic range (136,740 ac (55,335 ha)) and limited dispersal 
abilities. These traits may increase its vulnerability to stochastic 
(rare, chance) events such as epidemics or large, severe fires because 
a single event can occur within all or a large portion of the range, 
and individuals may be unable to escape the disturbance or recolonize 
habitat following extirpation. The petitioners claim that these 
salamanders are rare, patchily distributed, and easily extirpated by 
disturbances, making them highly vulnerable to extinction (Greenwald 
and Curry 2007, p. 1). However, current research suggests that Scott 
Bar salamanders are in fact well-distributed within their range, that 
they occur at high densities in some areas, and that populations 
persist in managed landscapes (see ``Range and Distribution'' and 
Factor A for the Siskiyou Mountains salamander). These traits act to 
decrease the potential vulnerability conferred on this species by its 
small range. Severe disturbances such as clear-cutting or intense 
wildfires may result in negative effects to abundance or population 
structure of this species (as described under Factor A for the Siskiyou 
Mountains salamander), but there is no evidence that they result in 
significant losses of populations, and populations appear to recover 
over time.
    Although there is evidence that fire size and intensity may have 
increased in the Klamath-Siskiyou region, large fires with mixed 
severity are characteristic of the natural disturbance regime (Odion et 
al. 2004, p. 933; Agee 1993, pp. 388-389) within which these 
salamanders have evolved. However, a large wildfire that affects the 
majority of the range of the Scott Bar salamander is a plausible 
description of a significant stochastic event. Large fires such as the 
2002 Biscuit Fire in southern Oregon may encompass an area similar to 
or larger than the range of this species. This does not, however, 
demonstrate that a fire of this magnitude is likely to threaten the 
Scott Bar salamander in the foreseeable future. The diverse topography 
and patchy distribution of habitats within the salamanders' range 
suggests that a large fire would be unlikely to have homogeneous 
effects at a large scale. The resulting mosaic pattern of fire effects, 
combined with the salamanders' ability to remain protected underground 
and persist during postfire vegetation recovery, indicates that the 
threat posed by such a stochastic event would be unlikely to result in 
large-scale extirpation of populations.

Summary of Factor E

    The uncertain nature of climate change predictions, particularly 
predictions of future precipitation patterns, precludes a meaningful 
evaluation of potential impacts to Scott Bar salamander populations 
resulting from future climate conditions. We find that, although 
stochastic events such as large wildfires may occur within a large 
portion of this salamanders' restricted range, Scott Bar salamanders 
appear to persist following wildfires and other disturbances, to 
recover as vegetation is re-established following disturbance, and have 
adequate numbers of well-distributed populations throughout their range 
to allow for persistence and viability of this species. We therefore 
conclude that the Scott Bar salamander is not now, or in the 
foreseeable future, threatened by the individual or cumulative effects 
of climate change or stochastic events such as epidemics or large, 
severe wildfires.

Finding

    We assessed the best available scientific and commercial 
information regarding threats faced by the Scott Bar salamander. We 
have reviewed the petition, information available in our files, and 
information submitted to us following our 90-day petition finding (72 
FR 14750; March 29, 2007). We also consulted with recognized salamander 
experts, and Federal and private land managers, and arranged for 
researchers to initiate field studies to assess the distribution of 
genetic entities within the salamander complex and demographic response 
of these species to forest structure and management practices.
    We find little support for the petitioners' claim that the Scott 
Bar salamander is threatened by habitat destruction caused by timber 
harvesting and wildfire, and that existing regulatory mechanisms are 
inadequate to protect the species. While the available information 
suggests that Scott Bar salamanders may be positively associated with 
older forest conditions, the majority of studies and available field 
data show the species occupying a wide range of forest conditions, 
including previously harvested areas. Recent research indicates that 
these salamanders persist and populations recover as vegetation is re-
established in intensively disturbed habitats. Less-intensive 
disturbances such as forest thinning and mixed-effects wildfire appear 
to have minor or short-term impacts on salamander abundance. There is 
no reliable evidence that indicates loss of populations or curtailment 
of this species' range has occurred.
    We acknowledge that the abundance and population structure of Scott 
Bar salamander populations may be

[[Page 4415]]

negatively affected by intensive timber harvesting practices such as 
clear-cutting. The extent and magnitude of such practices, however, are 
severely limited by a number of regulatory mechanisms and other factors 
operating within the salamanders' range, as evidenced by the steep 
decline in timber harvest levels on Federal lands that constitute 78 
percent of the species' range. Although levels of timber harvesting are 
higher on private timberlands, such lands constitute only 22 percent of 
the species' range and occur as small parcels interspersed among 
Federal lands. The small proportion of the range consisting of private 
lands, coupled with the ability of Scott Bar salamanders to persist in 
managed landscapes, leads us to conclude that forest management 
activities on Federal or private lands do not pose a substantial threat 
to this species.
    Several complementary regulatory mechanisms provide protection for 
Scott Bar salamanders and their habitats. On Federal lands constituting 
78 percent of the species' range, the NWFP's system of land use 
allocations and management guidelines impose substantial limitations on 
the amount and intensity of land management activities, as evidenced by 
the dramatic decline in timber harvest levels observed since the NWFP 
was implemented. For this reason, the elimination of the Survey and 
Manage Program, which has provided protection specifically to occupied 
salamander locations, does not pose a substantial threat to the 
species.
    As a species, the Scott Bar salamander exhibits several 
characteristics that, when combined, suggest that Scott Bar salamanders 
are resilient to stochastic events such as large wildfires. Populations 
of Scott Bar salamanders are distributed among several watersheds, and 
abundance within populations can be high. There are 115 known locations 
within the estimated range of this species, and the majority of 
suitable habitat has not been surveyed. These population 
characteristics, combined with the species' apparent ability to persist 
and recover following habitat disturbance, acts to reduce any potential 
threat posed by stochastic events. Our evaluation of climate change 
modeling for the geographic area inhabited by the salamanders does not 
support the contention that future climate poses a threat to Scott Bar 
salamanders, because it is not currently possible to forecast future 
precipitation regimes.
    Our evaluation of the five listing factors does not support the 
contention that there are threats of sufficient imminence, intensity, 
or magnitude as to cause substantial losses of population distribution 
or viability of the Scott Bar salamander. Therefore, we do not find 
that the Scott Bar salamander is in danger of extinction (endangered), 
nor is it likely to become endangered within the foreseeable future 
(threatened) across its range. Therefore, listing the species as 
threatened or endangered under the Act is not warranted at this time.
    Under the Services' DPS policy, (61 FR 4722, February 7, 1996) 
three elements are considered in the decision concerning the 
establishment and classification of a possible DPS. These are applied 
similarly for additions to the Lists of Endangered and Threatened 
Wildlife and Plants. These elements include: (1) The discreteness of a 
population in relation to the remainder of the species to which it 
belongs; (2) the significance of the population segment to the species 
to which it belongs; and (3) the population segment's conservation 
status in relation to the Act's standards for listing, delisting, or 
reclassification (i.e., is the population segment endangered or 
threatened). We are not aware of any information that would lead us to 
conclude that the Scott Bar salamander is comprised of population 
segments that are either discrete or significant. Therefore, we have 
not analyzed the Scott Bar salamander under the Services' DPS policy.

Significant Portion of the Range Analysis

    Having determined that the Siskiyou Mountains salamander, the 
Applegate salamander DPS of Siskiyou Mountains salamander, the Grider 
DPS of Siskiyou Mountains salamander, and the Scott Bar salamander do 
not meet the definition of a threatened or endangered species, we must 
next consider whether there are any significant portions of their 
ranges where the species or DPS is in danger of extinction or is likely 
to become endangered in the foreseeable future.
    On March 16, 2007, a formal opinion was issued by the Solicitor of 
the Department of the Interior, ``The Meaning of `In Danger of 
Extinction Throughout All or a Significant Portion of Its Range' '' 
(USDI 2007c). We have summarized our interpretation of that opinion and 
the underlying statutory language below. A portion of a species' range 
(in this case, ``species'' refers to the Siskiyou Mountains salamander, 
the Scott Bar salamander, and both Siskiyou Mountains salamander DPSs) 
is significant if it is part of the current range of the species and it 
contributes substantially to the representation, resiliency, or 
redundancy of the species. The contribution must be at a level such 
that its loss would result in a decrease in the ability to conserve the 
species.
    We acknowledge that the Ninth Circuit Court of Appeals decision in 
Defenders of Wildlife v. Norton, 258 F.3d 1136 (2001) can be 
interpreted to require that in determining whether a species is 
threatened or endangered throughout a significant portion of its range, 
the Service should consider whether lost historical range (as opposed 
to current range) constitutes a significant portion of the range of the 
species at issue. While this is not our interpretation of the case or 
the statute, we conclude that there are no such areas for the Siskiyou 
Mountains salamander, the Applegate DPS of the Siskiyou salamander, the 
Grider DPS of the Siskiyou salamander, or the Scott Bar salamander. As 
we discussed in detail in our assessment of threats to each species, 
there is no evidence of range contraction for any of the species. We 
have no evidence to suggest that the occupied range of any member of 
the Siskiyou Mountains salamander Complex is different from its 
historical range.
    In determining whether a species is threatened or endangered in a 
significant portion of its range, we first identify any portions of the 
range of the species 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 
threatened or endangered. To identify only those portions that warrant 
further consideration, we determine whether there is substantial 
information indicating that (i) The portions may be significant and 
(ii) the species may be in danger of extinction there or likely to 
become so within the foreseeable future. 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 essentially uniform 
throughout its range, no portion is likely to warrant further 
consideration. Moreover, if any concentration of threats applies only 
to portions of the range that are unimportant to the conservation of 
the species, such portions will not warrant further consideration.
    If we identify any portions that warrant further consideration, we 
then determine whether in fact the species is threatened or endangered 
in any significant portion of its range.

[[Page 4416]]

Depending on the biology of the species, its range, and the threats it 
faces, it may be more efficient for the Service to address the 
significance question first, or the status question first. Thus, if the 
Service determines that a portion of the range is not significant, the 
Service need not determine whether the species is threatened or 
endangered there. If the Service determines that the species is not 
threatened or endangered in a portion of its range, the Service need 
not determine if that portion is significant. If the Service determines 
that both a portion of the range of a species is significant and the 
species is threatened or endangered there, the Service will specify 
that portion of the range as threatened or endangered pursuant to 
section 4(c)(1) of the Act.
    The terms ``resiliency,'' ``redundancy,'' and ``representation'' 
are intended to be indicators of the conservation value of portions of 
the range. Resiliency of a species allows the species to recover from 
periodic disturbance. A species will likely be more resilient if large 
populations exist in high-quality habitat that is distributed 
throughout the range of the species in such a way as to capture the 
environmental variability found within the range of the species. In 
addition, the portion may contribute to resiliency for other reasons--
for instance, it may contain an important concentration of certain 
types of habitat that are necessary for the species to carry out its 
life-history functions, such as breeding, feeding, migration, 
dispersal, or wintering. Redundancy of populations may be needed to 
provide a margin of safety for the species to withstand catastrophic 
events. This does not mean that any portion that provides redundancy is 
a significant portion of the range of a species. The idea is to 
conserve enough areas of the range such that random perturbations in 
the system act on only a few populations. Therefore, each area must be 
examined based on whether that area provides an increment of redundancy 
is important to the conservation of the species. Adequate 
representation ensures that the species' adaptive capabilities are 
conserved. Specifically, the portion should be evaluated to see how it 
contributes to the genetic diversity of the species. The loss of 
genetically based diversity may substantially reduce the ability of the 
species to respond and adapt to future environmental changes. A 
peripheral population may contribute meaningfully to representation if 
there is evidence that it provides genetic diversity due to its 
location on the margin of the species' habitat requirements.

Siskiyou Mountains Salamander

    The Applegate and Grider DPSs together constitute the entirety of 
the range of the Siskiyou Mountains salamander. We have previously 
determined, however, that neither DPS is threatened or endangered 
across its range. Therefore, according to the formal opinion on 
significant portion of the range (USDOI 2007), we should then evaluate 
whether any significant portion of the range of a DPS may warrant 
listing.

Applegate Salamander DPS of Siskiyou Mountains Salamander

    To determine whether the Applegate salamander DPS is threatened in 
a significant portion of its range, we first addressed whether any 
portions of the range of the Applegate salamander DPS warrant further 
consideration. Our analysis indicates that the conservation status of 
the species is essentially the same throughout its range; there is no 
area within the range of the Applegate salamander DPS where potential 
threats to this species are significantly concentrated or are 
substantially greater than in other portions of the range. And, as we 
explained in detail in our analysis of the status of the species, none 
of the threats faced by the species, alone or in combination, are 
sufficient to place it in danger of extinction now (endangered) or in 
the foreseeable future (threatened).
    We found no evidence that populations of Applegate salamander DPS 
are concentrated in any geographic portion of the range that would 
increase the vulnerability of this DPS to a particular threat. The 440 
known Applegate salamander locations and suitable habitat are widely 
distributed across the DPS's range, and large areas of suitable habitat 
remain unsurveyed.
    We have analyzed the threats to the Applegate salamander DPS and 
have determined that they are not concentrated within any geographic 
portion of the range, and no significant areas within the DPS's range 
have been determined to face any greater threats. Potential threats to 
the DPS on Federal lands are addressed by existing land use regulations 
such as the NWFP, in combination with the Special Status Species 
program, such that no areas face significant threats which are not 
being managed. We find that private timberlands do not constitute a 
significant proportion of the Applegate salamander DPS's range because 
(1) Private lands constitute a minor proportion (15 percent) of the 
range of the Applegate salamander, and (2) private lands within the 
range of the species occur as small parcels in a ``checkerboard'' 
pattern with Federal lands or as isolated parcels, reducing the 
potential for threats to be concentrated in a geographic portion of the 
larger range. For these reasons, we find that there are no portions of 
the Applegate salamander DPS's range that warrant further consideration 
as significant portions of the range.
    We do not find that the Applegate salamander DPS is in danger of 
extinction (endangered) now, nor is it likely to become endangered 
within the foreseeable future (threatened) throughout all or a 
significant portion of its range. Therefore, listing the Applegate 
salamander DPS as threatened or endangered under the Act is not 
warranted at this time.

Grider Salamander DPS of Siskiyou Mountains Salamander

    Applying the process described above for determining whether a 
species is threatened in a significant portion of its range, we also 
addressed whether any portions of the range of the Grider salamander 
DPS warrant further consideration. Our evaluation of the distribution 
of Grider salamander DPS populations and potential threats indicates 
that the conservation status of the species is essentially the same 
throughout its range; there is no area within the range of the Grider 
salamander DPS where potential threats to this species are 
significantly concentrated or are substantially greater than in other 
portions of the range. And, as we explained in detail in our analysis 
of the status of the species, none of the threats faced by the species, 
alone or in combination, are sufficient to place it in danger of 
extinction now (endangered) or in the foreseeable future (threatened).
    We found no evidence that populations of this DPS are concentrated 
in any geographic portion of the range that would increase the 
vulnerability of this DPS to a particular threat. The 76 known Grider 
salamander locations and suitable habitat are widely distributed across 
the DPS's range, and large areas of suitable habitat remain unsurveyed.
    We have analyzed the threats to the Grider salamander DPS and have 
determined that they are not concentrated within any geographic portion 
of the range, and no significant areas within the DPS's range have been 
determined to face any greater threats. Potential threats to the DPS on 
Federal lands are addressed by existing land use regulations such as 
the NWFP, such that no areas face significant threats which are not 
being managed. We find that

[[Page 4417]]

private timberlands do not constitute a significant proportion of the 
Grider salamander DPS's range because (1) Private lands constitute a 
minor proportion (9 percent) of the range of the Grider salamander DPS, 
and (2) private lands within the range of the DPS occur as small 
parcels in a ``checkerboard'' pattern with Federal lands or as isolated 
parcels, reducing the potential for threats to be concentrated in a 
geographic portion of the larger range. Based on the reasons described 
above, we find that there are no portions of the Grider salamander 
DPS's range that warrant further consideration as significant portions 
of the range.
    We do not find that the Grider salamander DPS is in danger of 
extinction (endangered) now, nor is it likely to become endangered 
within the foreseeable future (threatened) throughout all or a 
significant portion of its range. Therefore, listing the Grider 
salamander DPS as threatened or endangered under the Act is not 
warranted at this time.

Scott Bar Salamander

    To determine whether the Scott Bar salamander is threatened in a 
significant portion of its range, we first addressed whether any 
portions of the range of the Scott Bar salamander warrant further 
consideration. Our evaluation of the distribution of Scott Bar 
salamander populations and potential threats indicates that the 
conservation status of the species is essentially the same throughout 
its range; there is no area within the range of the Scott Bar 
salamander where potential threats to this species are significantly 
concentrated or are substantially greater than in other portions of the 
range. And, as we explained in detail in our analysis of the status of 
the species, none of the threats faced by the species, alone or in 
combination, are sufficient to place it in danger of extinction now 
(endangered) or in the foreseeable future (threatened).
    We found no evidence that populations of Scott Bar salamanders are 
concentrated in any geographic portion of the range that would increase 
the vulnerability of this species to a particular threat. The 115 known 
Scott Bar salamander locations and suitable habitat are widely 
distributed across the species' range, and large areas of suitable 
habitat remain unsurveyed. The higher numbers of salamander locations 
on private lands is the result of mandatory surveys, and does not 
suggest the presence of larger or more concentrated populations on 
private lands.
    Existing land use regulations, such as the NWFP, provide protection 
for the Scott Bar salamander on Federal lands while CESA provides 
substantial protection for the salamander on private lands in 
California. Further, even if the CESA protections on private lands were 
eliminated, the threats facing the Scott Bar salamander would not 
significantly increase because the private lands are not concentrated 
in a particular geographical area, but rather occur in a 
``checkerboard'' pattern interspersed with Federal lands. This pattern 
of landownership serves to reduce the potential impacts on the 
salamander of timber harvest and other habitat disturbing activities on 
the relatively small portion (22 percent) of the species range that 
occurs on private lands, and to maintain redundancy, distribution, and 
connectivity among Scott Bar salamander populations. For these reasons, 
we conclude that there are no portions of the Scott Bar salamander's 
range that warrant further consideration as significant portions of the 
range.
    We do not find that the Scott Bar salamander is in danger of 
extinction (endangered) now, nor is it likely to become endangered 
within the foreseeable future (threatened) throughout all or a 
significant portion of its range. Therefore, listing the species as 
threatened or endangered under the Act is not warranted at this time.
    We make this finding at a time when Federal conservation efforts 
focused specifically on Applegate, Grider, and Scott Bar salamanders 
are in flux. Given the very recent discontinuation of the Survey and 
Manage Program and the fact that Survey and Manage guidelines are still 
applicable to ongoing Federal projects for at least another year, 
Federal agencies have had little time to develop and implement 
conservation strategies under their Special Status Species Programs. 
The Conservation Strategy for the Siskiyou Mountains Salamander, 
Northern Portion of the Range (Olson et al. 2007) covers the entire 
range of the Applegate salamander; the KNF is currently finalizing a 
Conservation Strategy for the Grider salamander and Scott Bar 
salamander. Both of these conservation strategies are modeled closely 
after the existing Survey and Manage guidance for the salamanders, but 
neither was evaluated as an existing conservation effort under PECE, or 
considered in our evaluation of threats to the species. Despite the 
fact that we did not rely on these existing and potential conservation 
efforts in our determination that the Siskiyou Mountains salamander 
group does not warrant protection under the Act, we note that these 
efforts by Federal agencies may in the future play an important role in 
the conservation of the species by acting as a hedge against 
uncertainty associated with future land management policies and our 
understanding of the ecology of these species. This finding represents 
our evaluation of the best currently available scientific information 
on the poorly known species, the environment they inhabit, and land 
management practices that may affect them, but we recognize the dynamic 
nature of our knowledge and land management policy. Through our 
participation in the development, implementation, and monitoring of 
these Conservation Strategies, as well as in ongoing field research of 
the species' habitat relationships, the Service will play a direct role 
in the future management and status of these salamanders.
    We will continue to assess the status of both clades of the 
Siskiyou Mountains salamander and Scott Bar salamander by working with 
the USFS, BLM, and other parties to the existing Conservation Strategy; 
research scientists; and other individuals or groups interested in 
contributing to the conservation of these species. Through our 
participation in regular reviews of the Conservation Strategy for the 
Siskiyou Mountains salamander, Northern Portion of the Range, we will 
monitor its effectiveness in eliminating and reducing threats to the 
Applegate salamander over the foreseeable future.
    We are continuing our involvement in the evaluation of habitat 
associations and effects of forest management on the Grider and Scott 
Bar salamanders. In 2005, the Service's Yreka Fish and Wildlife Office 
(YFWO), in cooperation with the USFS Redwood Sciences Laboratory and 
Humboldt State University, initiated research into the comparative 
abundance, population structure, and body condition of 60 Grider and 
Scott Bar salamander populations across a gradient of habitat 
conditions.
    We request that you submit any new information concerning the 
status of, or threats to, these species to our Yreka Fish and Wildlife 
Office (see ADDRESSES section) whenever it becomes available. New 
information will help us monitor these species and encourage their 
conservation. If an emergency situation develops for these or any other 
species, we will act to provide immediate protection.

References Cited

    A complete list of all references cited herein is available, upon 
request, from the Yreka Fish and Wildlife Office (see ADDRESSES 
section).

[[Page 4418]]

Author

    The primary authors of this notice are the staff of the Yreka Fish 
and Wildlife Office (see ADDRESSES).

Authority

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

    Dated: January 14, 2008.
 Kenneth Stansell,
Acting Director, U.S. Fish and Wildlife Service.
 [FR Doc. E8-918 Filed 1-23-08; 8:45 am]
BILLING CODE 4310-55-P