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Susitna-Watana Hydroelectric Project Document
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Title:
Terrestrial furbearer abundance and habitat use study, Study plan Section
10.10 : Final study plan SuWa 200
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Alaska Energy Authority
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Final study plan
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Series (ARLIS-assigned report number):
Susitna-Watana Hydroelectric Project document number 200
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[Anchorage : Alaska Energy Authority, 2013]
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July 2013
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Study plan Section 10.10
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15 p.
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All reports in the Susitna-Watana Hydroelectric Project Document series include an ARLIS-
produced cover page and an ARLIS-assigned number for uniformity and citability. All reports
are posted online at http://www.arlis.org/resources/susitna-watana/
Susitna-Watana Hydroelectric Project
(FERC No. 14241)
Terrestrial Furbearer Abundance and
Habitat Use Study
Study Plan Section 10.10
Final Study Plan
Alaska Energy Authority
July 2013
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10.10. Terrestrial Furbearer Abundance and Habitat Use
On December 14, 2012, Alaska Energy Authority (AEA) filed with the Federal Energy
Regulatory Commission (FERC or Commission) its Revised Study Plan (RSP), which included
58 individual study plans (AEA 2012). Section 10.10 of the RSP described the Terrestrial
Furbearer Abundance and Habitat Use Study. This study, which will be conducted as part of a
graduate thesis project supervised by Professor Laura Prugh of the University of Alaska
Fairbanks, focuses on providing current information on the abundance and habitat use of four
terrestrial furbearers (coyote, red fox, lynx, and marten). RSP 10.10 provided goals, objectives,
and proposed methods for data collection regarding terrestrial furbearers.
On February 1, 2013, FERC staff issued its study plan determination (February 1 SPD) for 44 of
the 58 studies, approving 31 studies as filed and 13 with modifications. RSP Section 10.10 was
one of the 31 studies approved with no modifications. As such, in finalizing and issuing Final
Study Plan Section 10.10, AEA has made no modifications to this study from its Revised Study
Plan.
10.10.1. General Description of the Proposed Study
Terrestrial furbearer studies were initiated in 2012 and, as outlined here, will continue in 2013
and 2014. The terrestrial furbearer study will be conducted as part of a graduate thesis project
supervised by Professor Laura Prugh of the University of Alaska Fairbanks (UAF). Data and
reports pertinent to the goals of this Project will be provided by Dr. Prugh, whereas elements of
the larger UAF thesis project lie outside the context of impact assessment and mitigation and are
not included in this study plan or in the FERC licensing process.
Study Goal and Objectives
The goal of this study is to provide current information on the abundance and habitat use of four
species of terrestrial furbearers (coyote, red fox, lynx, and marten) for use in evaluating potential
Project-related impacts and identifying appropriate mitigation. The potential impacts of the
Project include habitat loss and fragmentation, increased human harvest and disturbance, and
changes in prey populations (AEA 2011). Accurate population estimates and habitat-use data are
important for adequately determining the amount of habitat loss and identifying the relative
likelihood and magnitude of changes in harvest. This information will be used to assess the
potential effects of the Project on furbearer populations, which will inform development of any
necessary protection, mitigation, and enhancement measures, which may include management
and monitoring plans.
Red fox, lynx, and marten are ecologically important and valuable furbearers. Coyotes also are
ecologically important but they are not as highly valued as furbearers. Although coyotes are
widely distributed throughout Alaska, little is known about their abundance or ecological effects.
The coyote is considered to be a “human commensal” species, benefiting from human activities
such as road construction and agriculture (Young and Jackson 1951). Coyotes may increase in
abundance as a result of the Project, and because they prey on a wide variety of large and small
game, and compete with and prey on foxes and lynx, changes in coyote abundance could have
effects on other wildlife resources.
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Trapper surveys show that Alaskans who trap in Game Management Units (GMUs) 11 and 13
are particularly concerned about the impact of coyotes on Dall’s sheep populations (Schwanke
2010). Several studies have found that coyotes are a major predator of Dall’s sheep lambs (Hoefs
and McTaggart-Cowan 1979; Scotton 1998; Arthur and Prugh 2010). Although preliminary
results from a study of Dall’s sheep survival in GMU subunit 13D showed little evidence of
coyote predation (Lohuis 2011), the area where that study was conducted contains more escape
terrain than does the study area. Terrain in the study area (located in GMU subunit 13E) is more
similar to the area studied by Arthur and Prugh (2010) in the northern foothills of the central
Alaska Range, where the coyote was the main predator of Dall’s sheep lambs.
This study has five specific objectives:
1) Develop population estimates of coyotes and red foxes through fecal genotyping and
genetic capture-recapture analyses using scats collected along trails and rivers throughout
the study area during winter months (January–March) in 2013 and 2014.
2) Develop a population estimate of marten through DNA-based capture-recapture analysis
using hair samples collected in the reservoir inundation zone using hair-snag tubes.
3) Develop a population estimate of lynx through DNA-based capture-recapture analysis
using hair samples collected throughout the study area using hair-snag plates.
4) Assess prey abundance in the study area by conducting snowshoe hare pellet counts and
estimating vole density using mark-recapture estimates from live trapping.
5) Compile habitat-use data for the furbearer species being studied, using aerial track
surveys.
The habitat-use data and species population estimates will be used to assess the potential impacts
of the Project on these populations, and to develop any necessary potential protection, mitigation,
and enhancement (PM&E) measures.
10.10.2. Existing Information and Need for Additional Information
The original Alaska Power Authority (APA) Susitna Hydroelectric Project study program
collected data on use of the Project area by marten (Gipson et al. 1982, 1984; Buskirk 1983,
1984; Buskirk and MacDonald 1984; Buskirk and McDonald 1989) and red fox (Hobgood
1984), but no information was collected on coyotes or lynx, aside from incidental sightings. The
APA Susitna Hydroelectric Project studies indicated that marten may be impacted by the
reservoir, because a substantial amount of their preferred habitat (mature spruce forest) occurs
within the inundation zone. The Alaska Department of Fish and Game (ADF&G) has not
conducted population estimates of small furbearers in GMU 13. Trapping reports indicate that
populations have experienced normal annual and cyclic fluctuations, but no indications of long-
term increases or decreases have been apparent (Schwanke 2010).
Major advances in the estimation of predator population sizes have occurred since the original
APA Susitna Hydroelectric Project studies were conducted in the 1980s. A large body of
literature has accumulated on the use of noninvasive genetic techniques to obtain population
estimates for numerous species around the world. Many studies of wolves, bears, wolverines,
coyotes, foxes, lynx, marten, river otters, and other species have successfully used noninvasive
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techniques to estimate population sizes (Mowat and Paetkau 2002; Waits and Paetkau 2005; Petit
and Valiere 2006; Long et al. 2008).
Marten is the most economically valuable furbearer in GMU 13 (Schwanke 2010). Loss of
habitat combined with increased access could lead to unsustainable levels of harvest and
population declines in marten and other furbearers. Thus, current population estimates are
needed to serve as a baseline for assessing the impact of the Project and for developing any
necessary PM&E measures.
The wildlife data gap analysis completed for the Project (ABR 2011) recommended using a
combination of aerial track surveys and noninvasive capture–recapture techniques to determine
current habitat use, movement patterns, and population sizes of furbearer species. In general,
aerial track survey techniques are appropriate and will be adopted, in particular for assessing
habitat use. However, aerial tracking methods may be inappropriate for estimating population
sizes of small terrestrial furbearers and mark-recapture studies are preferred. The aerial snow-
track survey method that provides estimates of population size is known as the survey-unit
probability estimator (SUPE; Becker et al. 1998, 2004) and the SUPE model was recommended
by ADF&G for the Project to obtain population information on wolverines. The method is
appropriate and has been well-tested for large furbearers such as wolves and wolverines, which
often travel over long distances in open habitats where tracks are possible to follow from the air.
Similarly, beaver and muskrat sign are also easy to see from the air.
However, the SUPE method has several assumptions and requirements that make it impractical
for population surveys of smaller terrestrial furbearers and ADF&G, in comments on the gap
analysis and preliminary study plans, recommended against its use for species other than
wolverine for the following reasons. First, the method requires following the full length of a
track from its end, where the animal is seen, back to its start, when the last snowfall ended. Small
furbearers often travel in tightly meandering routes within dense brush or forests and their tracks
can be obscured by snowshoe hare tracks. Coyotes prefer to travel on trails broken by other
species (e.g., wolf and moose trails) because they have high foot loading and avoid traveling in
deep snow (Murray and Boutin 1991), making their tracks easy to lose. Second, aerial tracking
relies on weather conditions that are uncommon (a fresh snowfall followed by several days of
calm weather) and a SUPE survey can take several days per species to conduct (Becker et al.
1998). Therefore, it is unlikely that weather conditions and availability of experienced personnel
would allow sufficient time to complete SUPE estimates for other furbearers in the study area in
addition to the planned SUPE estimates for wolves and wolverines. In addition, the SUPE has
not been tested on smaller furbearers. Validations of SUPE population estimates in areas with
known population sizes have occurred for wolves and cougars only, with mixed results
(Vansickle and Lindzey 1991; Patterson et al. 2004; Choate et al. 2006). Thus, although aerial
track transects may be useful for obtaining information on habitat use and movement patterns of
smaller furbearer species, accurate estimation of population sizes requires different methods. As
outlined below, mark-recapture methods are preferred for estimating population size of terrestrial
furbearers smaller than wolves or wolverine.
10.10.3. Study Area
The terrestrial furbearer study area (Figure 10.10-1) will include all terrestrial areas that are
safely accessible by snow machine within a 10-kilometer (6.2-mile) buffer zone surrounding the
areas that will be directly altered or disturbed by Project construction and operations, including
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facility sites, laydown/storage areas, the reservoir inundation zone, and access road and
transmission line corridors. Carnivores are wide-ranging animals that occur in low densities, so
sampling will need to extend upstream on the Susitna River above the inundation zone and as far
as 10 kilometers on either side of the inundation zone and access/transmission corridors. This
wider sampling is needed to obtain adequate sample sizes to calculate population density
estimates of furbearers, especially because this study will occur during the low phase of the hare
cycle when coyote and lynx numbers will be at cyclic lows. Although density estimation of
furbearers will require sampling over a larger study area, all samples will be geo-referenced so
that a total count of furbearers occupying the Project-affected area can be determined.
10.10.4. Study Methods
10.10.4.1. Sample Collection
Snow machine transects will be established along creeks and rivers throughout the study area
(i.e., along road and transmission corridors and the inundation zone). Transect placement and
length will depend on the terrain. Ideally, 4–5 transects, each approximately 30 km long, will be
established along natural animal movement corridors in the study area, such as creeks and rivers.
Transects along the Susitna River and Denali access corridor may be relatively long (40 –50 km),
with shorter transects extending up side drainages (e.g., Watana and Tsusena creeks). Transects
will be placed to ensure roughly equal coverage of the study area and to avoid gaps where
furbearers would not be encountered. Transects will be traveled daily on a rotating basis, so that
each transect will be traveled every week, from late January to early April in 2013 and 2014, and
all canid and felid scats will be collected. Scats will be collected with ziplock bags and then
placed within autoclave bags to prevent cross-contamination. Scats will be stored frozen, which
preserves DNA for analysis.
Unlike canids, lynx and marten do not preferentially travel on rivers and trails. Therefore, hair
snags will be used to obtain genetic material from those species. Lynx habitat within the study
area (i.e., areas with tree or shrub cover) will be divided into approximately 50 blocks. Each
block will be 25 square kilometers (9.65 square miles) in size, approximately the average size of
a lynx home range (Slough and Mowat 1996; Vashon et al. 2008). Two hair-snag plates will be
placed in each block, in locations that are accessible and likely to be encountered by lynx in the
area. Hair-snag plates will consist of an attractant that will cause lynx to rub and a barb to collect
a hair sample (Zielinski et al. 2006). Hair-snag stations will be checked bi-monthly during late
January–early April in 2013 and 2014, and all hairs found on barbs will be placed in coin
envelopes and stored in a dry location to preserve the DNA. Because marten home ranges are
small and a comprehensive survey of the entire study area would be impractical, the marten
survey will be restricted to the inundation zone. This zone, which is approximately 125 square
kilometers (48.3 square miles) in size, will be divided into 25 5-square-kilometer (1.9-square-
mile) blocks, roughly corresponding in size to the home range of female martens reported in this
area during the 1980s (3 to 6 square kilometers [1.2 to 2.3 square miles]; Buskirk 1983). Two
hair-snag tubes will be placed within each block in locations likely to be used by marten, as
described by Williams et al. (2009).
Snowshoe hare abundance will be determined by counting fecal pellets in 8–10 plots within the
study area. Pellet counts correspond closely to snowshoe hare density (Krebs et al. 1987). The
study area will be divided into 4–5 blocks of equal size, and two pellet-count plots will be
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randomly placed within each block, one in spruce forest and one in riparian habitat. Fifty circular
plots with a radius of 0.5 meter (1.6 feet) will be spaced 15 meters (49.2 feet) apart at each site,
and all pellets will be counted and cleared from the plots. In the first year of the study, pellets
will be aged, based on appearance, to estimate whether they are more or less than a year old
(Prugh and Krebs 2004).
The abundance of voles will be estimated by using live -trapping and mark–recapture methods in
8–10 plots. Two trapping grids will be established in spruce forest and in grassy meadow
habitats. Each grid will consist of 50 live-trap sites spaced 10 meters (32.8 feet) apart. The traps
will be operated for 1–5 nights. Captured voles will be weighed, ear-tagged, identified to species
and sex, and released. The proportion of recaptured tagged individuals to unmarked individuals
will be used to calculate an estimate of population abundance.
10.10.4.2. Genetic Analyses
The outer surface of each frozen scat will be scraped with a scalpel, and shavings will be placed
in 2-ml vials. DNA from hair samples will be extracted using Qiagen ® kits (a commercially
available DNA assay). Mitochondrial analyses will be used to determine the species
identification and sex of individuals that deposited each hair and scat sample. Genotypes will be
determined by amplifying DNA at six loci. Amplification will be repeated two to three times to
verify accuracy because DNA from feces and hairs sometimes is degraded and errors can occur
(Miller et al. 2002).
10.10.4.3. Habitat Use
Habitat use will be evaluated by conducting helicopter surveys of tracks in snow. Experienced
observers (such as ADF&G biologists or UAF graduate students) will fly predetermined transect
lines at slow speed and will use global positioning system (GPS) receivers to record the locations
of tracks encountered. These locations will be overlaid on habitat maps using ArcGIS® software
(ESRI, Redlands, California) to examine patterns of habitat use in the study area for each
furbearer species. This design is based on the helicopter-based track surveys that were conducted
in the Project area in the 1980s (Gipson et al. 1984). Surveys using fixed -wing aircraft are not
feasible because the aircraft cannot be flown slowly enough to detect and record tracks of small
furbearers in forested habitats (S. Buskirk, University of Wyoming, personal communication,
September 20, 2012).
10.10.4.4. Statistical Analyses and Data Interpretation
Once reliable genotypes are obtained, each genotyped sample is considered to be a “capture”
event. Spatially explicit capture–recapture (SECR) population estimates and confidence intervals
will be produced using the SECR package in program R (Efford et al. 2009; Efford 2011). By
including location data in the density estimation, this recently developed method combines
distance sampling and mark–recapture modeling techniques to better account for capture
heterogeneity. Survival, recruitment, and population growth rates will be estimated between
years using open mark–recapture estimators such as Cormack–Jolly–Seber and Pradel models in
the RMark package (Laake and Rexstad 2008).
Nearly all methods to estimate population density assume the population is closed to births,
deaths, immigration, and emigration. Violations of this assumption can inflate population
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estimates. Several measures will be implemented to address this issue. First, temporal subsets of
data for which the assumption of population closure may be valid will be analyzed. For example,
estimates can be obtained from samples collected during a single month, during which time the
per-capita odds of a death, dispersal, or immigration event are relatively low. Traditional mark-
recapture methods require several capture “sessions,” but accurate and precise estimates can be
obtained using spatially explicit methods from a single session (Efford et al. 2009). Although
estimates from temporal subsets may be less precise (resulting in wide confidence intervals) than
estimates obtained from pooling samples during each winter season, they will allow evaluation
of the potential bias in the pooled estimates.
Because lynx and coyote population dynamics are closely tied to the hare cycle, which is
currently in the low phase, the number of detected individuals of these species may be low.
Based on other studies conducted in Alaska and the Yukon (e.g., Buskirk and McDonald 1989;
O'Donoghue et al. 1997; Prugh et al. 2005), it is estimated that samples will be obtained from
approximately 10–25 individuals of each of the four furbearer species per year within the study
area. However, the precision of mark–recapture estimates is based largely on recapture rates,
rather than on the number of individuals captured (Pollock et al. 1990). Because a field crew will
be working intensively in the study area and collecting samples continuously throughout the
winter, recapture rates are expected to be quite high (0.7–0.8) and the population estimates fairly
precise.
Natural cycling of snowshoe hare numbers and wolf control efforts by ADF&G in the study area
may influence lynx and coyote abundance in the study area, making it difficult to isolate the
effects of Project activities on these species. To assess these potentially confounding factors,
abundance estimates and trends found in this study will be compared with findings from a
similar study being conducted in nearby Denali National Park and Preserve (DNPP) and the
Stampede corridor. Trends found in the DNPP/Stampede may indicate how furbearer populations
are fluctuating in response to the hare cycle in the absence of wolf control and in the absence of
Project activities. Hare-pellet counts will be conducted in the DNPP/Stampede area as well as in
this study area. Comparing baseline furbearer surveys in the Project area with surveys in the
DNPP/Stampede area may indicate how wolf control is affecting furbearers in this study area.
Furbearer harvest records may provide information on harvest levels in each area. This
comparison may be useful in subsequently determining which changes in furbearer populations
may be due to the Project activities and which changes may have occurred due to other factors.
Because marten and red foxes rely heavily on microtine rodents and other prey rather than hares
(Buskirk and MacDonald 1984; Gipson et al. 1984), the hare cycle is not expected to be a
confounding factor in the assessment of Project impacts on their populations.
10.10.4.5. Data Products
This terrestrial furbearer study will provide pre-construction baseline data for the study area,
including habitat-use data for use in developing habitat evaluation criteria. The terrestrial
furbearer study will provide a basis for impact assessment and for developing appropriate PM&E
measures.
The following data will be produced from this study:
1) Population estimates, with confidence intervals, for coyote, red fox, lynx, and marten in
2013 and 2014.
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2) Estimates of survival, recruitment, and population growth for coyotes, red foxes, lynx,
and marten between 2013 and 2014.
3) Habitat use and selection data based on aerial track surveys.
4) Snowshoe hare abundance estimates from pellet-count data in spruce and willow habitats.
5) Vole density estimates from live-trapping in meadow and forest habitats.
6) Genetic samples from furbearers in the study area, which will be stored for at least five
years after the study is completed.
An Initial Study Report will be prepared in 2014 and an Updated Study Report will be prepared
in 2015, each summarizing the study results produced to date, including an examination of the
population dynamics and habitat use of terrestrial furbearers in the study area. Geographic
Information System (GIS) mapping with layers showing the locations of study transects,
furbearer snow tracks, and genetic samples collected during the study will also be created. The
Updated Study Report will summarize the results for both years of study.
10.10.5. Consistency with Generally Accepted Scientific Practice
Noninvasive genotyping is a well-established technique to obtain reliable population estimates of
coyotes, red foxes, lynx, and marten. Fecal genotyping was used successfully to monitor coyote
population dynamics from 2000 to 2002 in the central Alaska Range (Prugh and Ritland 2005 ;
Prugh et al. 2005; Prugh et al. 2008).
10.10.6. Schedule
This study includes data collection, analyses, and reporting during both 2013 and 2014 and
extending into the first quarter of 2015 (Table 10.10-1). In August 2012, prey abundance data
were collected in the study area. Hare-pellet count grids were established and pellet counts were
conducted. Live-trapping of voles was also conducted in newly established trapping grids.
Selection of sampling sites and fieldwork will occur during January–March 2013 to collect
genetic samples and conduct track surveys. Laboratory analyses of genetic samples will be
conducted during April–August 2013 and field surveys for snowshoe hare pellet counts and vole
density estimates will occur in August 2013. Data analyses and preparation of the Initial Study
Report will occur during September–December 2013, with the Initial Study Report being
completed by February 2014. A similar schedule will be followed in 2014, with fieldwork during
January–March, genetic analyses during April–October, hare and vole sampling in August, and
final data analyses and report preparation during September–December. The Updated Study
Report will be completed by February 2015. Updates on the study progress will be provided
during Technical Workgroup meetings which will be held quarterly in 2013 and 2014.
10.10.7. Relationship with Other Studies
As depicted in Figure 10.10-2, the terrestrial furbearer study will initially benefit from
information from the Vegetation and Wildlife Habitat Mapping Study (Section 11.5), which will
provide preliminary habitat mapping data for the allocation of sampling sites for hare and vole
population indices. Otherwise, no data from other studies will be required for this study. Ground-
based winter surveys for hair and scat samples and aerial surveys of winter tracks will be
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conducted in 2013 and 2014, providing the basis for DNA-based, spatially explicit capture–
recapture analyses to estimate the population sizes of the study species and to derive estimates of
recruitment and survival. The winter track surveys will provide information on winter
distribution and habitat use of terrestrial furbearers to inform the Evaluation of Wildlife Habitat
Use Study (Section 10.19) and are also likely to provide incidental observations of aquatic
furbearers for that study (Section 10.11). The population data from this study will be used in
combination with the Wildlife Habitat Evaluation Study to assess potential impacts and to
develop appropriate PM&E measures for terrestrial furbearers, as appropriate.
All four species of terrestrial furbearers are predators and could be affected both directly by
Project activities and features and indirectly by effects on prey species. The primary impacts of
the Project on terrestrial furbearers could include the following:
Direct and indirect habitat loss and alteration, including potential effects on prey species.
Potential direct behavioral impacts to wildlife, such as attraction or avoidance, resulting
from vehicular use, noise, and increased human presence associated with Project
construction or operation.
Potential indirect behavioral impacts to wildlife, such as attraction or avoidance, resulting
from changes in hunting, vehicular use, noise, and increased human presence associated
with increased subsistence or recreational access that may be facilitated by Project
development.
Potential direct mortality due to vehicle strikes, exposure to contaminants, and attraction
to garbage and human activity.
Potential changes in wildlife mortality rates due to increased subsistence and sport
harvest facilitated by Project development.
Potential physical and/or behavioral blockage and alteration of mov ements due to
reservoir water and ice conditions.
Data on the distribution, abundance, and habitat use of terrestrial furbearers in the study area will
contribute to the assessment of Project impacts that will be conducted in 2015 for the FERC
License Application. Using GIS software, species abundance data recorded among different
habitat types can be combined with the spatially explicit wildlife habitat map of the Project area
that will be developed under the botanical resources study plans. Direct effects of habitat loss
and alteration by the Project can be evaluated by overlaying the reservoir impoundment, related
infrastructure areas, and access road and power transmission corridors onto the habitat map and
then quantifying the acreage of habitats affect ed. Indirect effects can also be assessed by
applying various buffer distances, estimated from the available information on the anticipated
effects. Data collected in this study of terrestrial furbearers can be used in combination with
information from the literature to conduct a GIS analysis of the geographic extent, frequency,
duration, and magnitude of Project effects on terrestrial furbearer populations. For coyotes,
foxes, lynx, and marten, population data from the terrestrial furbearer study will provide context
for assessing the magnitude of potential population-level impacts of direct and indirect habitat
loss. For snowshoe hares, pellet counts conducted by the Terrestrial Furbearer Study will provide
semi-quantitative assessment of population effects. Any necessary PM&E measures will be
developed, as appropriate, by examining the distribution and abundance of species among
habitats in relation to the geographic extent and seasonal timing of various Project activities.
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Separate studies of prey species in the Project area, including the Dall’s Sheep Study (Section
10.7), the Willow Ptarmigan Study (Section 10.17), and the Small Mammal Study (Section
10.12), will provide additional information on the impact of predatory terrestrial furbearers on
prey species and will improve the assessment of potential Project-related impacts for all species.
Existing data analyzed for the Large Carnivores Study (Section 10.8) and any additional surveys
by ADF&G to estimate wolf numbers in the region for ongoing state man agement programs will
contribute to an understanding of the relationship between large and small furbearer populations
and may help to assess whether future changes in furbearer abundance may be related to changes
in wolf density, prey availability, or Project-related impacts. The Wildlife Harvest Analysis
(Section 10.20) will help to predict the potential Project-related changes in harvest of terrestrial
furbearers and other predators in the study area.
10.10.8. Level of Effort and Cost
This study will require two field seasons to assess furbearer abundance prior to Project
construction. The first field season will involve substantial time spent scouting safe travel routes
and establishing protocols. Fieldwork will be conducted by a crew of two persons. Supervision,
data analysis, writing reports, and attending meetings are expected to require one month of the
study lead’s time per year. Genetic analyses will be conducted by an experienced technician.
Several fixed-wing airplane trips will be needed during each winter field season for access to
field sites and to haul snow machine fuel and miscellaneous field supplies . Approximately 18
hours of helicopter time will be required to conduct aerial track surveys each year. Materials to
make hair-snag stations and other consumables for genetic analyses will be required. Genetic
analyses for fecal and hair samples cost more than traditional genetic analyses (~$50/sample
instead of ~$30) because samples need to be analyzed 2–3 times to check for errors due to low
DNA quality or quantity. The total cost of the study is estimated to be $410,000 for both years,
including aircraft support.
10.10.9. Literature Cited
ABR. 2011. Wildlife data-gap analysis for the proposed Susitna–Watana Hydroelectric Project.
Draft report, August 16, 2011. Report for the Alaska Energy Authority by ABR, Inc.—
Environmental Research and Services, Fairbanks, Alaska. 114 pp.
AEA (Alaska Energy Authority). 2011. Pre-Application Document: Susitna–Watana
Hydroelectric Project FERC Project No. 14241. December 2011. Prepared for the Federal
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10.10.10. Tables
Table 10.10-1. Schedule for implementation of the Terrestrial Furbearer Study.
Activity
2012 2013 2014 2015
3 Q 4 Q 1 Q 2 Q 3 Q 4 Q 1 Q 2 Q 3 Q 4 Q 1 Q
Final selection of sampling sites;
field surveys to collect genetic samples;
aerial surveys of tracks
Genetic analyses
Snowshoe hare pellet counts and
vole density estimates
Data analyses
Initial Study Report Δ
Updated Study Report ▲
Legend:
Planned Activity
Δ Initial Study Report
▲ Updated Study Report
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10.10.11. Figures
Figure 10.10-1. Terrestrial furbearer study area.
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Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 15 July 2013
Vegetation & Wildlife
Habitat Mapping Study
(Section 11.5)
Preliminary habitat map
for sample allocation
(2Q–2013)
STUDY INTERDEPENDENCIES FOR TERRESTRIAL FURBEARER STUDY
Ground-based
surveys in
winter for hair &
scat samples
Aerial surveys of
tracks in winter
Prey sampling
(hare pellet
counts, vole
mark–recapture
estimates)
Evaluation of Wildlife
Habitat Use
(Section 10.19)
Indices of prey abundance
(3Q–2013 & 3Q–2014)
Winter distribution &
habitat use data
(2Q–2013 & 2Q–2014)
Population size,
recruitment & survival rate
estimates (4Q–2013
& 4Q–2014)
DNA-based, spatially
explicit capture–
recapture analyses
(3Q–2013 & 3Q–2014)
Figure 10.10-2. Study interdependencies for Terrestrial Furbearer Study.