Endangered and Threatened Wildlife and Plants; Final Rule Removing the Virginia Northern Flying Squirrel (Glaucomys sabrinus fuscus) From the Federal List of Endangered and Threatened Wildlife, 50226-50247 [E8-19607]

Agencies

• Fish and Wildlife Service
• DEPARTMENT OF THE INTERIOR

[Federal Register Volume 73, Number 166 (Tuesday, August 26, 2008)]
[Rules and Regulations]
[Pages 50226-50247]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E8-19607]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[FWS-R5-ES-2008-0005; 92220-1113-0000-C6]
RIN 1018-AT37


Endangered and Threatened Wildlife and Plants; Final Rule 
Removing the Virginia Northern Flying Squirrel (Glaucomys sabrinus 
fuscus) From the Federal List of Endangered and Threatened Wildlife

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Final rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), hereby 
remove the Virginia northern flying squirrel (Glaucomys sabrinus 
fuscus), now more commonly known as the West Virginia northern flying 
squirrel (WVNFS), from the List of Threatened and Endangered Wildlife 
due to recovery. This action is based on a review of the best available 
scientific and commercial data, which indicate that the subspecies is 
no longer endangered or threatened with extinction, or likely to become 
so within the foreseeable future. Habitat regeneration and recovery 
actions have resulted in a reduction in the threats, which has led to: 
(1) A significant increase in the number of known WVNFS captures and 
distinct capture locations; (2) verification of multiple-generation 
reproduction and persistence throughout the range; (3) proven WVNFS 
resiliency; and (4) substantial improvement and continued expansion of 
suitable habitat rangewide.

DATES: This rule becomes effective September 25, 2008.

ADDRESSES: Comments and materials we received, as well as supporting 
documentation used in preparation of this final rule, are available for 
inspection, by appointment, during normal business hours, at our West 
Virginia Field Office, 694 Beverly Pike, Elkins, West Virginia 26241. 
Call (304) 636-6586 to make arrangements.

FOR FURTHER INFORMATION CONTACT: Diane Lynch, Regional Listing 
Coordinator, Northeast Regional Office, 300 Westgate Center, Hadley, MA 
01035 (telephone: 413-253-8628); or Tom Chapman, Field Office 
Supervisor, or Laura Hill, Assistant Field Supervisor, West Virginia 
Field Office (see ADDRESSES).

SUPPLEMENTARY INFORMATION:

Background

    The northern flying squirrel, Glaucomys sabrinus, consists of 25 
subspecies, including the Virginia northern flying squirrel, G. s. 
fuscus. Miller (1936, p. 143) first described G. s. fuscus, based on 
specimens collected in the Appalachian Mountains of eastern West 
Virginia. The Virginia northern flying squirrel was listed as 
endangered under the Endangered Species Act (Act) of 1973, as amended 
(16 U.S.C. 1531 et seq.) effective on July 31, 1985 (Service 1985 (50 
FR 26999)). However, it was subsequently determined that a more 
suitable common name for G. s. fuscus is the West Virginia northern 
flying squirrel, due to the majority of the subspecies' range occurring 
in West Virginia; thus, we refer to G. s. fuscus as West Virginia 
northern flying squirrel (WVNFS) throughout the rest of this document. 
Information about the WVNFS' life history can be found in our final 
listing rule (50 FR 26999), the Appalachian Northern Flying Squirrels 
Recovery Plan (Service 1990, pp. 1-11), and the WVNFS 5-year review 
(Service 2006a, pp. 6-10).

Previous Federal Actions

    On December 19, 2006, we published a proposed rule to delist the 
WVNFS (71 FR 75924). Additional information regarding previous Federal 
actions for the WVNFS can be obtained by consulting the subspecies' 
regulatory profile found at: https://ecos.fws.gov/speciesProfile/
SpeciesReport.do?spcode=A09R.

Recovery

    In 1990, the original recovery plan was approved, and at the time, 
the recovery criteria as they apply to the WVNFS were deemed objective, 
measurable, and adequate (Service 1990, p. 19). The original recovery 
criteria were not specifically reviewed or updated in the 2001 recovery 
plan amendment (Service 2001, pp. 1-6). Instead, the focus of the 2001 
amendment was an update to Appendix A, Guidelines for Habitat 
Identification and Management for the WVNFS. Implementation of the 
amended Appendix A guidelines by the Monongahela National Forest (MNF) 
effectively abated the main threat to the squirrel (i.e., habitat loss 
from timber management) throughout the majority of its range, by 
eliminating adverse impacts on all suitable habitat on the MNF without 
having to prove WVNFS presence (Service 2001, pp. 1-6; Service 2006a, 
pp. 3-4).
    Recovery plans are not regulatory documents and are instead 
intended to provide guidance to the Service, States, and other partners 
on methods of minimizing threats to listed species and on criteria that 
may be used to determine when recovery is achieved. There are many 
paths to accomplishing recovery of a species, and recovery may be 
achieved without all criteria being fully met. For example, one or more 
criteria may have been exceeded while other criteria may not have been 
accomplished. In that instance, the Service may judge that, overall, 
the threats have been minimized sufficiently and the species is robust 
enough to reclassify the species from endangered to threatened or to 
delist the species. In other cases, recovery opportunities may have 
been recognized that were not known at the time the recovery plan was 
finalized. These opportunities may be used instead of methods 
identified in the recovery plan. Likewise, information on the species 
may be learned that was not known at the time the recovery plan was 
finalized. This new information may change the extent to which criteria 
need to be met for recognizing recovery of the species. Overall, 
recovery of species is a dynamic process requiring adaptive management, 
and judging the degree of recovery of a species is also an adaptive 
management process that may, or may

[[Page 50227]]

not, fully follow the guidance provided in a recovery plan.
    In the case of the WVNFS, new information on the subspecies has 
been learned that was not known at the time the recovery plan and the 
amendment were finalized. This new information includes habitat 
modeling efforts completed in 2006, completion of a forest plan 
amendment in 2006 with substantial provisions for protection of WVNFS 
and its habitat, our compilation in 2005 of the 20+ years of survey 
data, and our re-analysis of WVNFS persistence and geographic 
distribution based upon them. This new information changes the extent 
to which two of the four Recovery Plan criteria need to be met for 
recognizing recovery of the subspecies. Further details related to each 
recovery criterion are available in the Service-prepared document 
Analysis of Recovery Criteria for the West Virginia Northern Flying 
Squirrel (Service 2007a, pp. 1-16). An attachment to this document, 
``Table 3, Land use designations, restrictions, and primary management 
emphases in WVNFS habitat on the MNF,'' provides supplementary 
information for downlisting criterion number 3. Based on our analysis 
of the best available data, we believe that the intents of the original 
recovery criteria have been met.
    In conjunction with the analysis of the recovery criteria, we 
analyzed the threats to the WVNFS under the framework of the five 
factors established in the Act. This analysis of the threats was based 
in part on the most recent 5-year review of the subspecies completed in 
2006 (Service 2006a, pp. 1-20). This is available at https://
www.fws.gov/northeast/pdf/flysqrev.pdf. A further detailed discussion 
of the five factors is contained in the Summary of Factors Affecting 
the Species section of this rule below.

Summary of Public Comments

    In our proposed rule (71 FR 75924), we requested that all 
interested parties submit information, data, and comments concerning: 
(1) Biological, commercial, trade, or other relevant data concerning 
any threat (or lack thereof) to the WVNFS; (2) additional information 
on the range, distribution, and population size of the WVNFS and its 
habitat; (3) the location of any additional populations of the WVNFS; 
and (4) data on population trends. The comment period was from December 
19, 2006, through April 23, 2007 (71 FR 75924; 72 FR 7852; 72 FR 9913).
    During the 120-day comment period, we received a total of 4,808 
comments. Of these comments, we consider 18 (6 from peer reviewers and 
12 from other sources) to be substantive. The majority of comments 
received were form letters objecting to the proposed delisting rule but 
providing no new or supporting information.

A. Distribution Concerns

    Issue 1--Some commenters asked us to quantify what portion of the 
historical range is currently occupied by WVNFS.
    Response--The historical range of WVNFS essentially corresponds to 
the distribution of old growth red spruce-northern hardwood forest 
(500,000 to 600,000 acres (ac)) prior to logging and fires at the turn 
of the 20th century. Much of the historical red spruce has been 
replaced by northern hardwoods. Current estimates of the amount of 
WVNFS habitat vary widely from 242,000 ac (U.S. Department of 
Agriculture (USDA), Northern Research Station 2006, unpublished map) to 
600,000+ ac (Menzel et al. 2006b, p. 4), across which the WVNFS is 
widely dispersed.
    Historically, the red spruce-northern hardwood forest encompassed 
portions of eight counties, extending from the vicinity of Mount Storm 
(Grant County) in the north, to Cold Knob (Greenbrier County) in the 
south, east to the Allegheny Front (Pendleton and Highland Counties), 
and west to Webster County. Based upon monitoring from 1985 to the 
present, the WVNFS still occupies portions of these same eight 
counties, roughly corresponding to 85 percent of the extent (breadth 
and width) of the historical range. With exception of the extreme 
northern portions of Grant County (roughly 5 percent of the historical 
range), and the area from Briery Knob south to Cold Knob in Greenbrier 
County (collectively less than 10 percent of the historical range), the 
outer boundaries of the current distribution of the WVNFS closely match 
the extent of its historical range (Service 2007a, Figure 1). 
Additional information can be found on page 75926 of the proposed 
delisting rule (71 FR 75924).

B. Population Concerns

    Issue 1--Some commenters expressed concern about an absence of 
population information and trend data. These commenters stated the 
Service had failed to consider population growth, population size, and 
linkages to other populations. Some commenters expressed concern about 
the use of persistence as an indicator of population health or 
stability and noted that the Service had not clearly defined the term 
``persistence.'' The commenters stated that this approach is flawed 
because it is not tied to knowledge of the population, but merely to 
subspecies presence, which can be explained by immigration from other 
populations.
    Response--The Service has considered population dynamics when 
assessing the status of the WVNFS using the best available scientific 
data. The Service considers persistence to be the best indicator of 
successfully reproducing populations for this subspecies, given its 
poor detectability, its life history characteristics, and the 20+ years 
of data from presence/absence surveys.
    We define persistence as continuing captures of WVNFS over multiple 
generations at previously documented sites throughout the historical 
range. Because WVNFS first reproduces at 1-2 years, and has a 
relatively short life span, averaging approximately 3 years, 
persistence at a single monitoring site over 5 years indicates 
successful reproduction across multiple (three to five) generations 
(Service 2007c, p. 10). The Service has analyzed presence/absence data 
to determine persistence of WVNFS across its range, taking into 
consideration detectability rates, life span, reproductive capacity, 
dispersal capability, linkages to other populations, and the naturally 
patchy habitat distribution of the subspecies (Service 2007c, pp. 5-6, 
9-11). These data consistently indicate a relatively high degree of 
persistence (roughly 80 percent) across the landscape, and are not 
indicative of a declining population of WVNFS. The data available for 
the remaining landscape (roughly 20 percent) does not represent an 
absence or lack of persistence of the WVNFS, but rather is indicative 
of the WVNFS' life history traits (i.e., elusive and hard to capture). 
Therefore, the data is simply less conclusive. This remaining landscape 
(roughly 20 percent) is still habitat for the WVNFS but success rates 
for capturing the WVNFS are lower. The persistence of WVNFS is likely 
facilitated by immigration. See Issues 2, 3, and 4 and their responses 
under this section for additional information.
    Issue 2--Some commenters believe the Service must conduct a 
Population Viability Analysis (PVA) to identify a minimum viable 
population before a decision on delisting the WVNFS is made. These 
commenters noted that genetics-based computer models of minimum viable 
population sizes generally indicate that population sizes on the order 
of thousands of individuals (low thousands or higher) may be needed. In 
contrast, another commenter submitted a copy of a manuscript by Smith 
and Person (2007, pp. 626-636) that evaluated the estimated persistence

[[Page 50228]]

of a northern flying squirrel subspecies in fragmented habitats in 
southeast Alaska. This commenter concluded that dispersal likely will 
be the key to northern flying squirrel population viability, not total 
population size of individual patches.
    Response--A genetics-based computer model to identify minimum 
population sizes for WVNFS does not currently exist. In our view, there 
is insufficient information available to support an accurate or 
credible genetics-based PVA model for WVNFS, and such an analysis would 
rely upon too many variables whose values would be speculative. Given 
the nature of the WVNFS life history and habitat information currently 
available, we believe that estimates of persistence, and an analysis of 
functional habitat connectivity, are the most credible form of PVA 
analysis. We therefore have done these analyses using the best 
available scientific data (for more detail, see Service 2007c, pp. 5-6, 
9-11) resulting in evidence of persistence and a high degree of habitat 
connectivity.
    We also have considered the recent work by Smith and Person (2007, 
pp. 626-636), who developed a birth-death process model to examine 
persistence of populations of a different northern flying squirrel 
subspecies in hypothetical, old-growth reserves isolated in managed 
landscapes in Alaska. We agree with these authors that functional 
habitat connectivity is more important to WVNFS population viability 
than total population size rangewide, or population sizes of individual 
habitat patches (See Issues 3 and 4 and their responses below).
    Issue 3--Some commenters expressed concerns that habitat reserves 
may be too few, small, degraded, and isolated to support viable 
populations of WVNFS. These commenters emphasized the importance of 
functional habitat connectivity.
    Response--Within the range of the WVNFS in the central 
Appalachians, there are numerous patches of high-quality, second-growth 
red spruce forest, with individual trees that are near maximum size and 
age, within an almost continuous matrix of more highly variable, 
second-growth red spruce and northern hardwood forest conditions. The 
habitat is still relatively well connected from the standpoint of WVNFS 
movement and does not significantly limit dispersal and movements 
(Service 2007c, Figure 1). Within the range of the WVNFS, above 3,200 
feet (ft), approximately 96 percent of the land is forested (627,237 
ac) (USDA Forest Service 2007, unpubl. map). Patch sizes on the MNF 
also are fairly large and connected by numerous forested linkages, 
facilitating the likelihood of WVNFS dispersal (Service 2007c, p. 6, 
Figure 1). For example, radio-tagged male WVNFS and other subspecies of 
northern flying squirrels have demonstrated an ability to make sudden, 
long-distance movements, presumably to find females. Some individuals 
have traveled up to 2 kilometers (1.2 miles) in a night during the 
mating season, which is from late winter to early spring (Smith 2007a, 
p. 871; Menzel 2003, p. 77, 117; Terry 2004, p. 18; Weigl et al. 1999, 
pp. 59-62; Weigl et al. 2002, p. 37, 145).
    Smith and Person (2007) modeled habitat reserve size for northern 
flying squirrels in Alaska. Habitat reserves must sustain individual 
insular populations, or the matrix of managed lands between reserves 
must allow dispersal among reserves to maintain wildlife populations 
within a metapopulation structure (Smith and Person 2007, p. 633). Out 
of an abundance of caution, Smith and Person (2007, p. 628) modeled the 
first scenario to estimate the persistence of northern flying squirrel 
populations occupying isolated fragments of habitat in a matrix of 
unsuitable habitat within a large 2-million-ac landscape in Alaska (p. 
628).
    Lacking conclusive evidence of dispersal, the authors assumed their 
populations were closed (i.e., no immigration or emigration). They also 
assumed the habitat was static (i.e., patch size and patch quality are 
constant over as long as a 100-year period). Neither of these 
assumptions fits the situation in the central Appalachians where many, 
if not most, of the habitat patches containing WVNFS are connected by 
habitat, and through passive and active management, conditions are 
expected to continue improving. In addition, the authors relied heavily 
on 3 years of local demographic data and data from a longer-term study 
in Canada. These demographic data may be dissimilar to those of WVNFS 
in West Virginia and Virginia. For example, the authors used an 
estimated average litter size of 2, which is low compared to the WVNFS 
average litter size of 2.5-3.0 (Reynolds et al. 1999, p. 346; Stihler 
et al. 1998, p. 178). Estimated survival rates also may have been low 
because the value was based on recaptures of tagged individuals, and 
the lack of a recapture does not mean a squirrel has died.
    That said Smith and Person do provide a framework for judging the 
relative magnitude of patch sizes that may be needed for northern 
flying squirrel persistence in large forested landscapes. Smith and 
Person (2007, p. 631, Table 5) estimated that the minimum area of an 
isolated patch of contiguous habitat to confidently sustain populations 
for at least 100 years without immigration/emigration was 11,414 ac 
(4,621 hectares (ha)) (P=0.90). Furthermore, there was a high 
probability that G. sabrinus could persist in smaller ([gteqt]245-ac 
[99-ha]) isolated habitat patches for 25 years without migration (p. 
631). Smith and Person (2007, p. 633) concluded that large reserves may 
not need to be contiguous, because interspersed lower-quality habitats 
can support northern flying squirrels for a short time and likely 
facilitate dispersal between patches of higher-quality habitat (Smith 
and Person 2007, p. 633).
    Because of the many assumptions, described above, of this model, 
which do not transfer well to the central Appalachians, we decided to 
do a coarse comparison of minimum patch sizes. Because the landscape 
for WVNFS appears to have a higher degree of functional connectivity 
than the study area in Alaska, we looked at the total acreages of 
contiguous and connected suitable habitat within each of seven core 
areas. [Five ``core areas'' were identified at the time the 1990 
recovery plan was written (Service 1990. p. 16) as clusters of capture 
sites, and are referred to in the plan as Geographical Recovery Areas. 
Two more clusters were later identified when surveys found additional 
WVNFSs. Collectively these seven areas (hereafter called ``core 
areas'') encompass the entire extant distribution of WVNFS.] Out of an 
abundance of caution, we assumed these seven core areas were 
geographically separated (no immigration/emigration among them), 
although this likely is not the case. Using these conservative 
assumptions, the ``minimum patch size of contiguous habitat'' within 
each core area ranges from 9,353 ac (3,787 ha) for the smallest core 
area (Stuart Knob) to 120,484 ac (48,779 ha) for the largest core area 
(Cheat). Six of the seven core areas exceed the minimum patch size 
identified by Smith and Person (2007, p. 631) as necessary to 
confidently sustain populations for at least 100 years without 
immigration/emigration (11,414 ac or 4,621 ha). Thus we infer that 
there is adequate habitat for persistence of WVNFS populations within 
most, if not all, of the core areas.
    Whereas habitat conditions in Alaska (small, isolated, old-growth 
forest fragments in a matrix of unsuitable habitat) are quite 
dissimilar to those in the central Appalachians (large, well-connected 
patches of predominantly second-growth forest in a matrix of

[[Page 50229]]

suitable habitat), it appears that habitat reserves of sufficient 
quantity, quality, and connectivity exist to sustain populations of 
WVNFS with influences of immigration and emigration. This habitat 
matrix provides a high degree of functional connectivity, as evidenced 
by persistence over multiple generations at monitoring sites across a 
range of forest conditions (Service 2007c, pp. 9-11).
    Issue 4--Some commenters asked the Service to analyze the viability 
of WVNFS metapopulations (multiple, relatively isolated breeding 
units). These commenters cited Weigl (2007, p. 903), who claimed that 
``some second growth stands may well appear to support healthy 
densities of squirrels, but, in reality, are population sinks for 
migrants from neighboring old growth habitats and thus may not 
permanently maintain viable populations.'' These commenters suggested 
the WVNFS may be undergoing a population decline that is influenced by 
source-sink dynamics of meta-population theory.
    Response--In response to this comment, the Service has conducted 
additional analyses to look for evidence of population sinks and 
sources in the central Appalachians. We found no evidence that the few 
remaining old growth patches of habitat in the central Appalachians, or 
other optimal habitat, are operating as potential sources of WVNFS 
recruits that disperse into suboptimal habitat (potential sinks) where 
populations are not sustained. Rather, our analysis of 21 years of 
monitoring shows no evidence of localized extirpation since the 
subspecies was listed. The WVNFS persists in or near all of the 
historical areas where it was originally known at the time of listing. 
Persistence of WVNFS across the range over multiple generations is 
consistently high, consistently distributed across habitat types 
(varying from 70 to 86 percent persistence) and geographic zones 
(varying from 80 to 85 percent persistence), and not significantly 
different from expected values (Smith 2007a, p. 871; Service 2007c, p. 
11, Table 1). Nestlings and juveniles are routinely documented at 
monitoring sites (76 percent of sites) (Service 2007c, p. 9). Because 
WVNFS has a relatively short life span (averaging approximately 3 
years), and first reproduces at age 1 or 2, persistence at a single 
monitoring site over 5 years indicates successful reproduction across 
multiple (3+) generations. In addition, the observed roughly 1:1 sex 
ratio (492 males, 539 females) is within the range needed for normal 
reproductive performance (Service 2007c, p. 11). Males are most likely 
to disperse, presumably to seek females (Ford 2007a). There is no 
indication of a predominance of dispersing males or juvenile males, 
which could be indicative of a meta-population sink dynamic (such as an 
emigration front of individuals leaving former territory), or of a 
meta-population source-dynamic (such as a colonizing front of 
individuals moving into former territory) (Ford 2007a). Collectively, 
these data show a relatively high degree of population stability and 
consistent habitat occupancy across multiple generations.
    Issue 5--Some commenters noted that the chance of capturing a WVNFS 
in a nest box is confounded by a very low rate of occupancy, plasticity 
in nest site selection, availability of nest sites, and relative 
abundance of WVNFS. These commenters state that it is as important to 
understand why an individual is present as to understand why it is not 
present. They state that a major caveat of relying on the nest box data 
as a measure of persistence is that it does not tell us anything about 
the habitat, and that it is impossible to infer what is optimal habitat 
and if it is available and can support the WVNFS.
    Response--The Service agrees that all of the factors mentioned 
above affect the chance of capturing a WVNFS; however, we disagree 
about inferences that can be drawn from persistence data. Continued 
persistence of WVNFS over the past century and occupation throughout 
most of its historical range tell us much about habitat and indicate 
that sufficient quality and quantity of habitat exists regardless of 
what may be perceived as ``optimal'' habitat. Therefore, a strong 
inference can be made regarding habitat suitability based on the 
persistence, successful reproduction, and sex ratios that lack any 
indication of population sink dynamics (Service 2007c, pp 11, Table 1).
    Issue 6--Some commenters cited a paper by Weigl (2007, p. 900) as 
evidence that the WVNFS may have a longer life span than previously 
assumed. These commenters suggested that if this is true, then the 
Service may need to reanalyze reproductive data and conclusions about 
persistence.
    Response--Weigl (2007, p. 900) referred to a study of a different 
G. sabrinus subspecies in the Pacific Northwest as evidence that WVNFS 
may be relatively long lived. In this study, three squirrels were known 
to be at least 7 years old at recapture; however, the majority of 
squirrels captured were not known to survive beyond 2-3 years (Villa et 
al. 1999, p.39). In the central Appalachians, recapture data for four 
WVNFS suggest the average lifespan is probably about 2 to 3 years (West 
Virginia Division of Natural Resources (WVDNR) and Service 2006, 
unpubl. data). Wells-Gosling and Heaney (1984, p. 4) also noted the 
average longevity of G. sabrinus was probably less than 4 years. Our 
previous conclusions about persistence remain valid based upon an 
average lifespan of 2-3 years.

C. Using the Best Available Science

    Issue 1--Some commenters were concerned about a lack of knowledge 
of the WVNFS life cycle and the consideration of science regarding the 
subspecies' ecology.
    Response--The WVNFS life cycle and ecology is fairly well known 
from numerous studies in peer-reviewed journals, books, and technical 
publications. The Service has considered the best available scientific 
and commercial data regarding WVNFS life history and ecology. For a 
full list of the literature cited in this final rule, please contact 
the West Virginia Field Office (see ADDRESSES).
    Issue 2--Whereas four peer reviewers and some commenters were 
satisfied the best available science and data had been used in the 
development of the proposed rule, two peer reviewers and some 
commenters questioned the quality or interpretation of data used to 
support the proposed rule. These commenters offered manuscripts in 
press, or alternative literature citations or explanations of the data.
    Response--The Service has reviewed the manuscripts in press (now 
subsequently published) and literature citations provided by 
commenters. We have considered and incorporated the information 
provided in these documents where appropriate in this final rule. We 
have incorporated these documents into our administrative record and 
cited them in this rule where appropriate (including, but not limited 
to, sections of the rule dealing with WVNFS population dynamics; 
habitat use, quantity, quality, and connectivity; and climate change). 
The peer-reviewed scientific journal articles, peer-reviewed agency 
reports, and other literature cited in the final rule represent the 
best available science relevant to the decision. None of the 
alternative explanations of the data were as persuasive as the sources 
we have cited in the final rule.
    Issue 3--Some commenters disagreed with a choice of words in the 
summary sections of the proposed rule which referred to ``an increase 
in the number of individual WVNFSs.'' These commenters claimed that 
there is no evidence of an increase, noting that 1,141 captures do not 
represent unique squirrels, because unknown portions

[[Page 50230]]

were recaptures. These commenters conducted an independent analysis of 
a WVNFS electronic database and field data reporting forms. They 
reported inconsistencies in the data base, and concluded there may have 
been as few as 654 unique captures. These commenters believe that such 
a low number of captures of unique individuals diminishes the 
credibility of conclusions reached by the Service about persistence.
    Some commenters also questioned whether an increase in WVNFS 
occupancy was simply a consequence of increased surveys or efficacy of 
survey efforts since listing. One commenter questioned our ability to 
detect a change in habitat occupancy.
    Response--Whereas the proposed rule did identify the total number 
of recaptures (71 FR 75926), the Service agrees that use of the phrase 
``increase in the number if individual WVNFSs'' was not accurate, as we 
have not estimated the size of the WVNFS population. We have corrected 
this wording in the final rule. Based upon data collected through 2005, 
there has been an increase in the total number of known captures, from 
10 at the time of listing, to 1,141 captures at the time of the 
proposed rule, of which there were 78 total recaptures (6.8 percent). 
Due to multiple recaptures of some individuals, these 78 total 
recaptures represent 62 individuals.
    Contrary to the commenters' estimate of 654 unique captures, we 
calculate that there were a total of 908 unique captures (760 unique 
captures of adults and 148 unique captures of juveniles). These 
estimates take into account unique recaptures and unmarked individuals. 
About 8 percent of the adults escaped before they could be marked. 
Also, contrary to the commenters' determination that ``several'' 
nestlings were not tagged, nearly all of the 133 nestlings and about 2 
percent of the 154 juveniles captured were not marked as a 
precautionary measure. Researchers believe that marking small 
individuals with ear tags and/or pit tags is an unnecessary procedure 
that could increase mortality (Stihler 2007). The fact that these 
individuals were not marked is inconsequential when considering that 
there is less than a 5 percent probability of subsequent recapture. 
Rather, the capture of nestlings or juveniles is a good sign of 
reproduction (25 percent of all captures).
    The increase in the number of capture locations is useful in 
evaluating the distribution of WVNFS within its range, but cannot be 
used to estimate population sizes. The number of captures has increased 
with increased survey effort. While the area covered by surveys has 
increased over time, the efficacy of capturing WVNFS remains low. Based 
on original methodologies used at the time of listing, and still 
predominantly in use today, roughly 2 percent of nest box or live trap 
checks result in detection of WVNFS (Terry 2004, p. 46; Service 2006b, 
p. 13). This estimate of detectability is a simple calculation of the 
proportion of nest box or live trap checks that resulted in WVNFS 
capture. We have not used this simple estimate of detectability to 
calculate changes in habitat occupancy over time as suggested by one 
commenter. We evaluated whether the existing data set could be analyzed 
using more rigorous models for estimating detectability and changes in 
habitat occupancy (MacKenzie et al. 2002, pp. 2248-2255; MacKenzie et 
al. 2003, pp. 2200-2207; MacKenzie 2005, pp. 849-860; MacKenzie 2006, 
1568-1584); however, we felt it inappropriate given that model 
assumptions would have been violated and could not be validated. While 
there has been an increase overall in survey area, the techniques used 
were the same and the intensity of work at sites has not varied 
significantly in the past 20 years.
    As a result of these comments, the WVDNR has checked the data base 
against field forms and has made a few minor corrections. These changes 
do not substantially alter previous statistics reported by the Service 
or conclusions reached about persistence.
    Issue 4--Some commenters noted that monitoring sites were not 
randomly selected, which builds in bias. These commenters recommended 
that such data not be used for estimating population.
    Response--The Service acknowledges that monitoring sites were not 
selected randomly. The goal of the presence/absence surveys was to find 
as many WVNFS as possible and to document their range and distribution. 
Consequently, few sites were placed in low-quality habitat, and many 
sites were placed in moderate or high-quality habitat. Because of this 
bias, the Service has not used these data to estimate population sizes, 
but rather to monitor presence/absence and persistence.

D. Genetic Concerns

    Issue 1--Some public commenters were concerned about a lack of 
genetic research that might indicate risks due to isolation (e.g., 
genetic drift, inbreeding) or existence of discrete populations 
meriting ESA protection.
    Response--We considered information from several studies using a 
variety of genetic markers. Allozymic analyses by Browne et al. (1999, 
pp. 205-214) found lower measures of polymorphism and heterozygosity in 
North Carolina, West Virginia, and Virginia populations of G. sabrinus 
compared with other northern flying squirrels, noting that population 
structure in the southeastern States is similar to that of other 
species that occupy habitat islands (Browne et al. 1999, p. 212). 
Similarly, allozyme and mitochondrial DNA data examined by Arbogast et 
al. (2005, pp. 123-133) showed lower diversity of G. s. fuscus and G. 
s. coloratus compared with conspecifics (other flying squirrel 
species), but not relative to populations of the widespread southern 
flying squirrel. Sparks' data from a small number of microsatellite 
loci showed moderate to high gene flow across populations of northern 
flying squirrels in West Virginia, Virginia, and North Carolina (Sparks 
2005, pp. 16 and 23). In addition, the coefficient of inbreeding failed 
to differ between populations at Cheat Mountain, West Virginia, and at 
an unfragmented forested landscape in Washington State (Sparks 2005, p. 
18). Also, no difference in levels of a parasitic helminth (a species 
of parasitic worm commonly found in the intestines of flying squirrels, 
the presence of which is often used as possible indicator of reduced 
fitness) was detected among G. sabrinus and two sympatric tree 
squirrels (Sparks 2005, pp. 19, 62).
    Arbogast et al. (2005, p. 130) and Weigl (2007, p. 902) speculate 
about potential future decreases in genetic diversity due to 
hypothetical habitat reductions. As discussed under Issue 3, Response 
to Comments, Section B--Population Concerns, however, we believe that 
habitat is still relatively well connected from the standpoint of WVNFS 
movements. Interspersed lower-quality habitats that can support 
northern flying squirrels for a short time will also facilitate the low 
levels of dispersal necessary to maintain allelic diversity and 
heterozygosity while conserving local adaptations. Furthermore, Sparks 
(2005, p. 29) suggests that G. sabrinus may have a population structure 
adapted to some degree of inbreeding tolerance.
    In summary, after review of the genetic studies referenced above, 
we have not detected any genetic risk to the WVNFS due to isolation. 
Additionally, we are aware of no genetic, behavioral, ecological, 
morphological, physiological, physical, or other information supporting 
the existence of distinct population segments within the WVNFS.

[[Page 50231]]

E. Habitat Modeling Concerns

    Issue 1--One peer reviewer and some commenters thought the Service 
had applied the Menzel et al. (2006b, pp. 1-10) model outside of its 
intended scope and for purposes not supported by the study the model is 
based upon. Some conclude that the Service is using the model to make a 
case that the agency can accurately predict habitat and WVNFS 
viability, by assuming that the model definitively predicts presence 
and absence.
    Response--Using logistic regression, Menzel et al. (2006b, pp. 1-
10) developed a Geographic Information System (GIS)-based habitat model 
for WVNFS in West Virginia by synthesizing micro- and macro-habitat 
relationship data. The Service has applied this model appropriately to 
gauge the relative abundance and quality of habitat rangewide and to 
broadly estimate the predicted distribution of WVNFS on the landscape. 
We have not assumed that the model definitively predicts presence/
absence of WVNFS. Nor have we argued that predicted habitat ensures 
WVNFS' viability; predicted habitat is only one component. The model 
can give insights, albeit coarse, on habitat quality and its 
distribution across the landscape. As noted in the final listing rule 
(50 FR 26999) and recovery plans (Service 1990, pp. 12-16) for this 
subspecies, the abundance and quality of habitat are keys to the 
recovery of WVNFS because habitat loss and degradation were the main 
factors that led to the subspecies being listed as endangered. We have 
used the model at a landscape level to predict habitat quality and look 
for evidence of sink-source metapopulation dynamics. We have also used 
the model to highlight where managers should conduct follow-up site 
visits to determine actual squirrel habitat or where managers could 
reasonably assume no occupation without a site visit. A manager could 
use Ford et al. (2004, pp. 430-438) at the individual forest stand 
level to verify the quality of the habitat or what the probability 
level of occupation would be for that specific location.
    Issue 2--Some commenters criticized the Menzel et al. (2006b, pp. 
1-10) habitat model for being unverified and untested.
    Response--The model has been verified and tested and proved to be 
quite accurate (81 percent) when the data were subjected to ground-
truthing procedures to determine correct classification rates of 
occupiable and non-occupiable habitat (Menzel et al. 2006b, p. 3-4). 
Staff from the WVDNR and MNF have used the model successfully to 
identify WVNFS habitat, corroborated by additional captures where the 
model had shown a high probability of occurrence.
    Issue 3--Some commenters stated that the Menzel model's prediction 
of habitat from tracking data should have been verified in following 
years (different temporal frame) and on different areas of the range 
(different spatial frame).
    Response--The actual telemetry data used by the Menzel model did 
span several years and different areas. The model is based on actual 
data, which have been verified.
    Issue 4--Some commenters criticized the Menzel model for containing 
several untested assumptions: (a) There is a direct relationship 
between nest box use and preferred habitat; (b) quality of habitat is 
predicted by elevation and vegetative community; and (c) data from 
spring and summer tracking reveals information on habitat use the 
remainder of the year.
    Response--Addressing assumptions (a) and (b), Menzel et al. (2004, 
pp. 355-368; 2006b, pp. 1-10; 2006a, pp. 204-210) does not assert that 
probability of occurrence equates directly to preferred habitat; 
however, there is a clear correlation between high probability habitat 
(>75 percent probability of WVNFS occupancy) and habitat components 
such as red spruce and high elevation that were preferred by radio-
collared individuals (Menzel et al. 2006a, pp. 206-207). Addressing 
assumption (c), data from winter telemetry studies at Snowshoe Mountain 
Resort and Canaan Valley National Wildlife Refuge (Ford et al. 2007 in 
press, pp. 6, 8) are similar to results from spring, summer and fall 
reported by Menzel et al. (2006a, pp. 206-207). Winter data confirm 
that male home ranges are larger than female home ranges and both sexes 
key in on red spruce-dominated habitats for foraging (Ford et al. 2007, 
pp. 4, 6, 7).
    Issue 5--Some commenters stated that the Menzel model was based on 
limited spatial and temporal data from 4 sites and 13 animals; 
therefore, results can be generalized only with great caution.
    Response--The Menzel et al. (2006b, p. 3) model is not based on a 
limited subset of the data, but rather is based on most of the capture 
data through 1999 and most of the telemetry data from WVNFS tracked in 
a variety of stand age-classes and compositions. All squirrels tracked 
for which home range sizes were calculated, had reached home range size 
asymptotes (the point on a graph indicating the minimum number of 
samples needed to calculate maximum home range size), indicating that 
sufficient location data exists to estimate home range size. Moreover, 
WVNFSs were tracked in a variety of poor to excellent habitat 
conditions. This methodology is consistent with similar examples of 
wildlife habitat data being collected from tagged individuals and then 
used in a modeling effort to extrapolate across a larger, but similar 
landscape (for example, Gibson et al. 2004, pp. 75-89; Posillico et al. 
2004, pp. 141-150). The Service believes it has interpreted these data 
appropriately.
    Issue 6--Some commenters stated that the Menzel model is a 
simplification of existing knowledge and does not account for important 
variables in WVNFS biology, such as forest age, structure, tree 
composition, and fungi. These commenters believe the model potentially 
overestimates optimal habitat by treating young forest the same as old 
forest, and by lumping other factors together (moist conditions, high 
rainfall, northern aspects, forest structure, suitable nest sites, food 
sources, etc.) based on elevation and spruce occurrence.
    Response--The Service concurs that Menzel et al. (2006b, pp. 1-10) 
is a simple habitat model that was meant to capture broad aspects of 
WVNFS distribution. The model tends to underestimate higher-quality 
habitat and to overestimate lesser-quality habitat, especially near the 
50 percent predicted probability of occurrence threshold (Ford 2007b). 
However, we still think the model is useful and reasonably accurate for 
gauging the relative abundance and quality of habitat rangewide and for 
predicting the distribution of WVNFS on the landscape, and represents 
the best available scientific and commercial data.

F. Ecosystem and Habitat Concerns

    Issue 1--Some commenters were concerned that delisting the WVNFS 
would jeopardize an entire ecosystem, especially when considering the 
critical role that WVNFS plays in dispersal and persistence of numerous 
fungi which have symbiotic relationships with trees.
    Response--The Service agrees that the WVNFS plays an important role 
in the red spruce-northern hardwood ecosystem (Smith 2007a, p. 862-863; 
Weigl 2007, pp.10-12). Habitat models for this subspecies implicitly 
recognize the symbiosis between WVNFS and tree fungus (Odom et al. 
2001, pp. 245-252; Menzel et al. 2006b, pp. 1-10). The Service does not 
expect that delisting the WVNFS will have negative consequences for the 
ecosystem. The red spruce-northern hardwood ecosystem upon which the 
WVNFS

[[Page 50232]]

depends has substantially recovered and continues to improve (also see 
Issue 4 in this same subsection below). The delisting process signifies 
elimination of endangerment of the WVNFS and elimination of the need 
for the Act's protections. Delisting is a procedural acknowledgement of 
the recovered ecological status of this subspecies and the ecosystem 
upon which it depends.
    Issue 2--One commenter stated that protection of habitat is serving 
as a proxy for the status of the subspecies. Protection of habitat is 
critical to protection of the subspecies but does not ensure recovery.
    Response--While protection of habitat is important to the status of 
the subspecies, it is not serving as a substitute for other factors. In 
analyzing whether the WVNFS has recovered, the Service has considered 
the reduction of all threats to the subspecies, including the 
destruction, modification, or curtailment of its habitat or range; 
overutilization; disease or predation; inadequacy of existing 
regulatory mechanisms; and other factors. See the Summary of Factors 
Affecting the Species section below for additional information.
    Issue 3--Some commenters stated that there is a lack of a clear 
definition of habitat for WVNFS due to insufficient information on 
habitat needs. Factors comprising optimal habitat are complex and 
poorly understood.
    Response--The work of Menzel et al. (2004, pp. 355-368; 2006b, pp. 
1-10), Ford et al. (2004, pp. 430-438; 2007 in press, pp. 4-7), and 
Mitchell (2001, pp. 441-442) clearly define WVNFS habitat and its 
characteristics.
    Issue 4--Some commenters, including two peer reviewers, thought the 
Service had overemphasized spruce as a habitat component for WVNFS. 
These commenters note that the WVNFS inhabits deciduous forest at lower 
elevations without a spruce component, and therefore should not be 
considered an obligate to red spruce forest. These commenters state 
that additional hardwood forest needs to be protected. Some commenters 
also disputed that red spruce is preferred habitat of WVNFS, 
identifying biases in the work by Menzel. These commenters state that 
the Menzel habitat model is based on a small sample of nest boxes 
located in red spruce habitat, skewing this monitoring program toward a 
finding of red spruce as preferred squirrel habitat; however, actual 
squirrel capture data seem to refute the exclusive focus on red spruce 
(Menzel 2003, p. 93).
    Response--The Service never meant to imply that the squirrel is an 
obligate of the red spruce forest. However, the ecosystem in which 
WVNFS evolved consisted of a significant red spruce component, and it 
would be inappropriate to de-emphasize this important habitat feature. 
The WVNFS can be quite cosmopolitan, living within majority red spruce 
to nearly complete red spruce cover types, to majority hardwood to 
nearly complete hardwood cover types where the red spruce-fir component 
is minimal (Stihler et al. 1995, p. 18; Menzel 2003, p. 68; Menzel et 
al. 2006a, pp. 207-208; Ford et al. 2004, pp. 433-434; Reynolds et al. 
1999, pp. 347-348). However, the preponderance of the data suggest a 
strong link to red spruce; there is a higher probability of WVNFS 
presence in areas with the most red spruce (as a percentage of the 
cover type) (Menzel 2003, p. 68; Ford et al. 2004, pp. 433-434, 2007 in 
press, pp. 12, 15-16; Menzel et al. 2006a, pp. 207-208). It is well 
documented that the entire range of the WVNFS was a red spruce 
dominated forest until heavily logged during the late 1800s and early 
1900s (Mielke 1987, p. 219; Schuler et al. 2002, p. 89; Menzel et al. 
2006b, p. 1; Rentch et al. 2007, pp. 440-442). Home range sizes also 
are smaller in areas with more red spruce, suggesting that habitat 
quality is better in these areas because WVNFS do not have to travel as 
far to meet their ecological needs (Menzel 2003, pp. 77; Ford et al. 
2007, p. 6).
    Additionally, no data in the central Appalachians show that WVNFS 
are heavily dependent upon pure hardwoods. Even so, protection of 
northern hardwood forest of considerable size is not a concern in the 
central Appalachians, since, within the range of WVNFS above 3,200 ft 
in elevation, approximately 96 percent (627,237 ac) of the land is 
forested (USDA Forest Service 2007, unpubl. map). At a coarser scale, 
within the more than 2 million ac of northern hardwoods in the high 
Allegheny landscape of West Virginia, Forest Inventory Analysis shows 
an approximately 15 percent increase in northern hardwoods from 1989 
(2,061,000 ac, SE = 4,400 ac) to 2000 (2,393,600 ac, SE = 4,200 ac) 
(Griffith and Widmann 2003, pp. 30, 32).
    Finally, Menzel (2003, p. 93) does not support the commenters' 
claims about bias. Sample bias was recognized and dealt with 
appropriately. The Menzel et al. (2006b, pp. 1-10) study used a 
sufficiently large sample of nest box and trap sites that produced 
WVNFS previous to 1999 in a statistical analysis. These occupied sites 
were then compared to 700+ locations that failed to produce WVNFS in a 
logistic regression analysis. Despite the fact that nest box and trap 
locations were skewed towards forest stands containing red spruce, 
captures occurred more frequently (in a greater proportion than habitat 
availability would suggest) in red spruce than in pure hardwood stands.
    Issue 5--Some commenters, including two of the six peer reviewers, 
expressed concern about the threat of extensive logging on Federal, 
State, and private lands within the range of the WVNFS. Some commenters 
claim the MNF proposes to log up to 40 percent of the area comprising 
Management Prescription (MP) 4.1, which focuses on red spruce and red 
spruce-northern hardwood restoration.
    Response--A substantial amount of WVNFS habitat is protected and 
managed consistently with the habitat needs of the WVNFS. Approximately 
79 percent of WVNFS habitat (189,785 ac) is protected from the threat 
of exploitive logging for the foreseeable future (Service 2007a, pp. 5-
8). Privately owned lands potentially subject to continued timbering 
(50,997 ac or 21 percent of WVNFS habitat) occur primarily at the edge 
of the subspecies' range (Service 2007a, p. 8). These lands are not 
critical to the subspecies' conservation, given the large amount of 
WVNFS potential habitat protected and managed on public lands in the 
core of the subspecies' range. [For more details on the degree of land 
protection, see criterion  3 in Service (2007a)].
    The current MNF Forest Plan (USDA Forest Service 2006a, chapters II 
and III), protects WVNFS habitat primarily through land use 
designations, a predominantly passive management strategy, and binding 
standards that effectively remove the threat of habitat loss (via 
logging and other disturbances) on all WVNFS habitat on the forest 
(164,560 ac or 68 percent of the habitat rangewide). Standards TE 63-66 
(USDA Forest Service 2006a, p, II-26-27) adopt and implement the 
provisions of appendix A of the recovery plan for the WVNFS, which 
severely limit vegetation management in all WVNFS habitat, including 
breeding, feeding, resting, and dispersal corridors (Service 2001, 
appendix A). Only specific actions that have no adverse effect to WVNFS 
habitat, a discountable or very minor effect, or that demonstrate a 
beneficial effect (such as habitat restoration) are allowed in WVNFS 
habitat forest-wide. Based upon the Forest Service's long-term (50+ 
years) desired conditions for the ecosystem (USDA Forest Service 2006a, 
p. III-12), the Forest Service's intent shown in a Memorandum of 
Understanding signed by the MNF (Service et al. 2007, pp. 3

[[Page 50233]]

and 8), conversations with MNF staff, and the absence of any 
information to the contrary, we reasonably expect these standards to 
continue to apply regardless of the Act's listing status of the WVNFS. 
This management strategy is also likely to continue post delisting, as 
the WVNFS would be managed by the Forest Service as a ``sensitive 
species'' (USDA Forest Service 2006c, p. 18).
    The commenters' reference to potential logging of 40 percent of the 
area of Management Prescription 4.1 appears to stem from a 
misunderstanding of forest-wide standards TE63-66 and how they 
interplay with the other standards on specific prescription areas. 
Prescription area 4.1 encompasses 153,600 ac, of which 59 percent 
(roughly 91,332 ac) has been mapped as WVNFS habitat and is protected 
from commercial logging by standards TE63-66. The remaining 41 percent 
of the area (62,268 ac) has not been mapped as WVNFS habitat. Within 
this 62,268-ac area, approximately 27,300 ac (or 18 percent of the 
total acreage in prescription area 4.1) have been tentatively 
identified as suitable for timber production (USDA Forest Service 
2006b, p. 3-354). These 27,300 ac may be logged contingent on site-
specific project review and field checks to verify that these lands are 
not WVNFS habitat. Thus, at most, 18 percent of the land in MP 4.1 
could be logged over the life of the Forest Plan and all of this land 
would need to be demonstrated to not be suitable habitat for WVNFS, 
prior to logging.
    Logging of areas that are not WVNFS habitat will also need to 
comply with an array of other applicable standards in the management 
direction for prescription area 4.1 (USDA Forest Service 2006a, pp. 
III-14 to III-16), such as standards 4118 and 4119, which place limits 
on the amount and timing of disturbances within harvest units (USDA 
Forest Service 2006a, p. III-15). Standard 4118 states that no more 
than 40 percent of forested National Forest System lands within each 
4.1 prescription area unit shall be harvested over a 10-year period. 
Standard 4119 requires that unforeseen activities, such as timber 
salvage or pipeline installation, shall be counted toward the 40 
percent disturbance standard in 4118. Thus there are additional limits 
on timbering, even in areas that are not WVNFS habitat, that further 
reduce forest disturbances.
    Limited logging in WVNFS habitat for purposes of restoration is 
also allowed in prescription area 4.1, consistent with standards TE 63-
66, as long as it can be demonstrated to result in a minor/discountable 
adverse effect or a beneficial effect to WVNFS. The Forest Service has 
an objective to restore approximately 1,000 to 5,000 ac of habitat over 
the next 10 years (USDA Forest Service 2006a, p. III-14, objective 
4107). Standard 4118 also applies to these restoration activities. 
Hence it places limits on the frequency of disturbances within stands.
    The Service is confident that these restoration efforts would 
benefit WVNFS in several ways, by: (1) Increasing amounts of coarse 
woody debris necessary for many fungal species; (2) increasing the size 
and importance of red spruce (an important fungal substrate); (3) 
increasing habitat patch size and connectivity; (4) increasing snags 
available as day dens for WVNFS; and (5) decreasing hard-mast 
production, thereby lessening stand value to the southern flying 
squirrel competitor (Menzel et al. 2006a, p. 208).
    Issue 6--Some commenters expressed a view that all old growth 
forest across the range of WVNFS needs to be protected. These 
commenters cited Smith (2007a, pp. 864-865, 877) and Weigl (2007, p. 
899, 902) as evidence of concerns about ongoing harvest of old growth 
forest, its replacement with plantations or regenerating stands, and 
the increasing fragmentation of much of the remaining habitat.
    Response--There is little to no harvesting occurring in old growth 
forests on public or private lands within the range of the WVNFS. There 
is very little old-growth remaining from the exploitive logging period 
in the late 1800s/early 1900s. On the MNF, old growth currently 
comprises less than 1 percent of the entire forest (USDA Forest Service 
2006a, p. B-1). In addition, areas identified as old growth on the MNF 
are not suitable or allowed to be cut. The remaining known old-growth 
areas on the forest are protected by Botanical Area, National Natural 
Landmark, or Scenic Area designations, and are managed through specific 
Forest Plan direction and standards that prohibit timber removal and 
restrict other types of vegetation management in these areas (USDA 
Forest Service 2006a, p. B-4). Furthermore, ``[t]imber harvest goals 
and objectives are based on achieving desired conditions for vegetation 
and habitat, not on regional economics'' (USDA Forest Service 2006b, 
Final Environmental Impact Statement (FEIS), Appendix I, p. I-152), so 
there is little risk of the MNF having adverse impacts on the WVNFS. 
Concerns about a significant increase in forest fragmentation 
throughout much of the remaining WVNFS habitat are unsubstantiated. 
There are no existing or predicted activities that are anticipated to 
significantly adversely affect forests within WVNFS range on a 
landscape level.
    Issue 7--Some public commenters cited a newspaper article as 
specific evidence that the impact of second home development in West 
Virginia is a significant threat to WVNFS. They requested that the 
Service reanalyze these impacts.
    Response--The Service has reanalyzed these impacts and come to the 
same conclusion as in its earlier analysis, that second home 
development is not currently a significant threat. The greatest 
development pressures in West Virginia are occurring, and are projected 
to continue to occur, outside of the range of the WVNFS, in the far 
eastern panhandle, and in and around the cities of Morgantown and 
Charleston (Stein et al. 2005, Figure 2). Second home development 
currently is occurring at the edge of the range of the WVNFS (primarily 
at Canaan Valley and Snowshoe Mountain). By 2030, housing density 
increases are projected to occur on private forests across 0 to 5 
percent of the area corresponding to the core of the range of WVNFS 
(Stein et al. 2005, Figure 2). Such losses, if they occur, would be at 
the periphery of the range and minor in relation to the 242,000 ac of 
WVNFS habitat that exist within a larger landscape encompassing the 
range of WVNFS that is 96 percent forested (USDA Forest Service 2007, 
unpub. map).
    Issue 8--Some commenters thought that the impacts of roads had not 
been adequately considered. These commenters stated that roads create 
absolute barriers to flying squirrel movement. These commenters were 
concerned that construction of Appalachian Corridor H (a four lane 
divided highway running from Weston, WV, to the Virginia line), in 
particular, will open the region to further development and will 
isolate populations of WVNFS in Blackwater Canyon from populations and 
suitable habitat south of the highway. Commenters were concerned that 
populations of WVNFS in Blackwater Canyon north of the highway may not 
be able to survive on the remaining small island of habitat. They 
criticized the Service for not discussing these impacts in more detail 
in the proposed rule or 5-year review.
    Response--Construction of Corridor H through the extreme northern 
part of the WVNFS range is not expected to result in significant 
impacts to WVNFS or its habitat. As explained in the Land Use Planning 
section of the Factor A

[[Page 50234]]

analysis below, sufficient habitat will remain on both sides of the 
highway to support WVNFS (Service 2006b, pp. 4-5, 16-29; 2007c, pp. 3-
4, 14-26). Additionally, a cumulative effects assessment, conducted by 
the West Virginia Department of Transportation (2006, pp. 17-19) 
suggests there is an adequate amount of non-environmentally sensitive, 
low-elevation land, which is not WVNFS habitat, and is available to 
support all development reasonably expected to occur as a result of the 
highway construction.
    Issue 9--Some commenters were concerned that mining, drilling for 
gas, and construction of wind turbines in the habitat of WVNFS are 
increasing and therefore pose a threat to WVNFS.
    Response--There is no evidence that these activities have in the 
past, or will in the future, significantly threaten the WVNFS. This 
conclusion is based upon Service review of impacts to WVNFS from permit 
applications for coal mining, gas, and wind power projects.
    Surface mine projects in West Virginia average 302 ac in size, and 
underground mines average 34 ac of surface disturbance (Office of 
Surface Mining (OSM) 2005, p. 2). Most coal mining activity is 
concentrated in six counties (Boone, Kanawha, Mingo, Logan, Marshall, 
and Monongalia) outside the range of the WVNFS (OSM 2005, p. 2). Within 
the range of WVNFS, small portions of Greenbrier, Randolph, Tucker, and 
Grant Counties have coal seams (OSM 2005, cover map); however, these 
areas were mined in the past and are not currently active. Given the 
cost of reopening a mine, it is unlikely that there would be a 
resurgence of active mining in these areas, considering that these 
sites require expensive acid-mine waste remediation (Fala 2007). In the 
21 years since the WVNFS's listing, there have been only 2 or 3 
projects out of thousands reviewed each year where the Service 
identified potential adverse effects from coal mining to WVNFS habitat, 
and each of these projects was in marginal habitat on the edge of the 
subspecies' range. The Service has no information suggesting that coal 
mining activities will expand into WVNFS habitat. Given this lack of 
evidence of a threat and the above prior history and acreages involved, 
the potential for future impacts to WVNFS from this activity appears 
remote and insignificant.
    The Service has noticed a recent increase in gas drilling 
applications in West Virginia; however, the footprint of these projects 
typically is small, averaging approximately 1.5 ac per gas well. These 
projects also tend to use existing, short (<1 mile long) gravel access 
roads which do not pose a barrier to WVNFS dispersal. In the 21 years 
since the WVNFS's listing, few if any gas projects have resulted in 
adverse impacts to WVNFS habitat, and none of these projects have 
resulted in take of WVNFS. The Service expects these trends to continue 
after the WVNFS is delisted. The minor impacts of these projects do not 
pose a substantial threat to WVNFS.
    There currently is one operating wind power project in West 
Virginia, two under construction, and one approved which will not be 
constructed. There also is one project in Virginia in the permitting 
application phase. These projects have ranged in size from 24 to 372 ac 
of disturbance. Neither the presently operative project nor the two 
under construction have had impacts to WVNFS or its habitat. Although 
the Service has noticed an increase in prospecting for wind power 
projects in West Virginia, only a minority of these potential projects 
might adversely impact WVNFS or its habitat. Three of the 13 projects 
the Service has reviewed initially identified potential adverse impacts 
to WVNFS habitat (two projects in West Virginia and one project in 
Virginia). Two of these projects ultimately avoided WVNFS habitat 
because of the Act, and one of these projects was withdrawn due to 
difficulties seeking access from the Forest Service. Although 
prospecting is currently occurring, nearly half of all prospective wind 
energy applications filed for grid interconnection study within the 
mid-Atlantic region are withdrawn (Boone 2006, pp. 1-2).
    On national forest lands, project proponents currently must seek 
separate authorization for prospecting (surveys and setting up 
meteorological stations), as well as the construction and operation of 
wind towers. Even after the WVNFS is delisted, proposed wind farms in 
national forests within the range of WVNFS range would still need to be 
consistent with standards and guidelines in the forest plans. 
Therefore, we conclude that while prospecting in wind farms is 
increasing, only a minority may materialize, and fewer still might 
adversely affect the WVNFS. Based on these projections and the small 
acreage potentially involved, we conclude that wind power will not pose 
a significant threat to WVNFS or its habitat.

G. Forest Pest Concerns

    Issue 1--Some commenters were concerned about the effects of beech 
bark disease and the hemlock woolly adelgid on the habitat of the 
WVNFS. Two peer reviewers noted that while these forest pests may have 
local impacts to WVNFS, they are not significant at the landscape 
level. Two peer reviewers discussed forest pests as potential threats 
but did not comment on their significance to WVNFS.
    Response--Any impacts to WVNFS habitat from beech bark disease or 
hemlock woolly adelgid are considered minor in the context of the 
subspecies' range. A decline in American beech, as a result of beech 
bark disease, should provide additional snags and coarse woody debris 
for WVNFS. Additionally, a decline in beech nuts would also reduce the 
f