usfws pinnacle 93009 letter uswf

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United States Department of the4i FISH AND WILDLIFE SERVICE " West Virginia Field Office 694 Beverly Pike Elkins, West Virginia 26241 September 30, 2009 Mr. Paul Kerlinger Curry & Kerlinger, LLC Post Office Box 453 Cape May, New Jersey 08212 Mr. Mike Sponsler BHE Environmental 5300 E. Main Street, Suite 101 Columbus, Ohio 43213-2580 Re: Comments on Wildlife Studies for the Pinnacle Wind Power Project, Mineral County, West Virginia, (PSC Case # 09-0360-E-CS) Dear Mr. Kerlinger and Mr. Sponsler: The U.S. Fish and Wildlife Service (Service) has reviewed the wildlife risk assessments conducted in support of the proposed Pinnacle Wind Power Project (Pinnacle) near the town of Keyser in Mineral County, West Virginia. The proposed wind facility will consist of twenty- three (23) turbines (418-feet or 1,379-meters tall at the top of rotor-swept area) aligned along the ridge of Green Mountain, a section of the Allegheny Front. The elevation of the project area varies from 2,514 to 2,851 feet (766 to 869 meters) above mean sea level. The proposed project includes construction of 0.75 mile (1.2 kilometers) of transmission line. Between 102 to 245 acres (41 to 99 hectares) of land will be cleared of vegetation for construction of the turbine towers, transmission lines, and other infrastructure. Following construction, most of these cleared areas will be allowed to regenerate. The comments we provide below pertain to the Habitat Characterization and Assessment of Rare, Threatened, and Endangered Species for the Pinnacle Wind Farm (BHE Environmental 2009a); the Avian Risk Assessment for the Pinnacle Wind Power Project (Kerlinger 2009); and the Bat Risk Assessment: Pinnacle Wind Farm (BHE Environmental 2009b). We submit these comments and recommendations pursuant to the Endangered Species Act of 1973 (ESA), as amended (16 U.S.C. 1531 et seq.), the Bald and Golden Eagle Protection Act (BGEPA) (16 U.S.C. 668 et seq.), and the Migratory Bird Treaty Act (MBTA) (16 U.S.C. 703 et seq.).

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Page 1: USFWS Pinnacle 93009 Letter USWF

United States Department of the4i

FISH AND WILDLIFE SERVICE "

West Virginia Field Office694 Beverly Pike

Elkins, West Virginia 26241

September 30, 2009

Mr. Paul KerlingerCurry & Kerlinger, LLCPost Office Box 453Cape May, New Jersey 08212

Mr. Mike SponslerBHE Environmental5300 E. Main Street, Suite 101Columbus, Ohio 43213-2580

Re:

Comments on Wildlife Studies for the Pinnacle Wind Power Project, Mineral County,West Virginia, (PSC Case # 09-0360-E-CS)

Dear Mr. Kerlinger and Mr. Sponsler:

The U.S. Fish and Wildlife Service (Service) has reviewed the wildlife risk assessmentsconducted in support of the proposed Pinnacle Wind Power Project (Pinnacle) near the town ofKeyser in Mineral County, West Virginia. The proposed wind facility will consist of twenty-three (23) turbines (418-feet or 1,379-meters tall at the top of rotor-swept area) aligned along theridge of Green Mountain, a section of the Allegheny Front. The elevation of the project areavaries from 2,514 to 2,851 feet (766 to 869 meters) above mean sea level. The proposed projectincludes construction of 0.75 mile (1.2 kilometers) of transmission line. Between 102 to 245acres (41 to 99 hectares) of land will be cleared of vegetation for construction of the turbinetowers, transmission lines, and other infrastructure. Following construction, most of thesecleared areas will be allowed to regenerate.

The comments we provide below pertain to the Habitat Characterization and Assessment ofRare, Threatened, and Endangered Species for the Pinnacle Wind Farm (BHE Environmental2009a); the Avian Risk Assessment for the Pinnacle Wind Power Project (Kerlinger 2009); andthe Bat Risk Assessment: Pinnacle Wind Farm (BHE Environmental 2009b). We submit thesecomments and recommendations pursuant to the Endangered Species Act of 1973 (ESA), asamended (16 U.S.C. 1531 et seq.), the Bald and Golden Eagle Protection Act (BGEPA) (16U.S.C. 668 et seq.), and the Migratory Bird Treaty Act (MBTA) (16 U.S.C. 703 et seq.).

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The Service identified several species and groups that may be impacted by the construction andoperation of the Pinnacle wind power facility in a letter to Ms. Becky Braeutigam dated April 13,2007. The letter noted that the Federally-listed endangered Indiana bat, the bald eagle, migratorybirds (including bald and golden eagles), and unlisted migratory bats may be affected eitherdirectly or indirectly by activities associated with the construction and operation of the facility,including: behavioral effects, habitat removal and fragmentation, increased human activity,maintenance of rights-of-way and roads, and collisions with turbine blades, among others.

The habitat characterization and assessment and the avian and bat risk assessments for theproposed Pinnacle Wind power project describe the potential for impacts to these identifiedspecies using the survey information, data from other wind power facilities, and literaturereviews. The Pinnacle risk assessments are based on a weight-of-evidence approach usingrelative measures (low, medium, and high) to determine the level of impact a particular stressor(i.e., construction activities, collision) will have on a species or group. This is an acceptableapproach that has been used by the Service and other Federal agencies to describe risk. Asfurther described below, we disagree, however, with conclusions drawn from these analyses.

Habitat Characterization and Assessment

The habitat characterization and assessment for rare and Federally-listed species on the Pinnaclestudy area described the habitat of the endangered Indiana bat on site as "minimal" based onprevious and ongoing disturbances on site and a minimal amount of preferred habitat in theturbine corridor (i.e. forested riparian areas and caves). However, the executive summary of thisreport noted that in the summer of 2008, a substantial portion of the 245-acre (98-hectare). projectarea was clear-cut. The area of timber cut was not stated but we assume it was on the order ofroughly 62 acres (25 hectares) during the time of year when bats were active. [The report refersto a total 102-acre (41-hectare) limit of disturbance for the project, and refers to 40 acres (16hectares) of young timber remaining on site. By subtraction, one can infer that roughly 62 acres(25 hectares) were cut.] We cannot tell from the scant details in the habitat characterizationreport, but it is possible that the ridgeline where the project is to be located originally containedmature trees which may have . provided higher levels of suitable roosting and foraging habitat forIndiana bats prior to the clear-cutting.

The bat risk assessment for Pinnacle (BHE 2009b, page 9) describes the ridgetop of the Pinnacleproject area as relatively mature forest (presumably prior to clear-cutting by the landowner). Thebat risk assessment also indicates that the proposed Pinnacle project prior to clear-cutting wasexpected to remove 0.04 percent of the forest in the county; and is therefore not a significant loss(BHE 2009b, p. 3). However, the proper context for comparison is not the entire county but theridgeline on which the Pinnacle project is proposed to be constructed. At a local level, the forestloss from Pinnacle is cumulative to the clear-cutting by the landowner which is expected toremove one-half to two-thirds of the trees from the ridge (BHE 2009b, page 3).

Because this endangered species uses mature trees for roosting, and uses forested habitat totravel to foraging areas (Butchkoski 2007), clearing of large areas of forested habitat coulddisrupt potential roost sites and travel corridors for this species. Remaining trees greater than a5-inch (12.8-centimeter) diameter-at-breast height should only be cut during the time of year

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when bats are in hibernation (November 15 through March 31). To compensate for forestclearing and habitat fragmentation on-site, we recommend protecting intact mature forest habitatoff-site.

Likewise, the habitat characterization report noted (post-clearcut) the lack of large trees suitablefor nesting by eagles. These forested impacts should be clarified and appropriately avoided,minimized, and mitigated. At a minimum, we recommend that Pinnacle commit to implementingthe recommendations on page 10 of the Avian Risk Assessment (Kerlinger 2009) regardingseasonal clearing restrictions for nesting birds, habitat restoration, and development of a forestmanagement plan.

The habitat characterization and assessment for Pinnacle also noted the high, likelihood ofoccurrence of several rare species that use talus and rock outcrops: small-footed bat, Alleghenywoodrat, eastern spotted skunk, and timber rattlesnake. Timber rattlesnakes were observed inabundance on site yet the report concluded a minimal likelihood the Pinnacle project willadversely affect rare reptiles. To avoid contributing to the need to list additional species underthe Federal Endangered Species Act, we recommend avoiding impacts to talus and rocky outcropareas that may be used as suitable habitat by small-footed bats and other sensitive species.

Avian Risk Assessment

Night Migrating Birds

No on-site observations of passage rate, flight altitude, or flight direction were used to assessrisks to nocturnally migrating birds at the proposed Pinnacle site. The collision risk to nightmigrants was assessed by reviewing previous studies conducted at other locations in the easternUnited States. The studies cited as most relevant to assessing collision risk at the Pinnacle siteare of two different types: radar studies (for estimating numbers, altitudes, and directions) andcarcass searches (for estimating collision mortality). Currently, there are no available studiesthat directly correlate radar observations with observed mortality at ridgeline locations.

Data from 23 wind facility post-construction avian mortality studies are presented to assess nightmigrant collision potential at the proposed Pinnacle site. Only four of these studies (Nicholson2001, 2002; Kerns and Kerlinger 2004; Fiedler et al. 2007; Young et al. 2009a) were conductedat ridge sites which are similar to the proposed Pinnacle location. Results of these four carcasssearch investigations indicate that approximately two to seven night migrants/turbine/year arekilled at eastern ridge top wind projects.

Of the 21 radar studies cited, only three (Mabee et al. 2006; Woodlot Alternatives, Inc 2005; and"Allegheny Ridge" unknown citation) were conducted at. ridge sites along the Allegheny Frontand are potentially useful for estimating passage rate, flight altitude, and flight direction of nightmigrants at the Pinnacle site. Mean passage rates reported in these studies varied from 187 to493 targets/kilometer/hour. Altitude observations referenced in the Pinnacle risk assessmentindicate that night migrants generally flew above the maximum height of industrial windturbines, with between 7 and 15 percent on average observed flying within the rotor-swept zone(below 410 feet or 1,353 meters). However, Stantec Consulting (2008a) reported that on some

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Mr. Paul Kerlinger and Mr. Mike SponslerSeptember 30, 2009

nights as many as 53 percent of night migrating birds crossing a nearby Allegheny Front ridgeflew below the 410-foot (1,353-meter) level. If similar conditions occur at the Pinnacle site, thepresence of industrial-scale wind turbines may present a significant collision risk to nightmigrants during peak migration and/or inclement weather conditions.

Eagles

We also are concerned about the risk of collision mortality to golden and bald eagles using theair space over the proposed Pinnacle wind power project. Results of the "Spring and Fall RaptorMigration Studies" contained in the Avian Risk Assessment for the Pinnacle Wind Power Project(Pinnacle Risk Assessment) confirm that the proposed project site lies in a major migratorypathway for the relatively small eastern population of golden eagles (Kerlinger 2009). Theauthor notes that "Fall Golden Eagle migration at Pinnacle is significant and comparable involume to that registered at some of the hawk watch sites that are considered the most importantinland in eastern North America" (Kerlinger 2009). The fall 2007 observation period at theproposed Pinnacle site was conducted between September 1 and December 15 and totaled 87observation days. During this period, 99 golden eagles and 57 bald eagles were observedpassing through the project area. The spring 2008 observation period occurred between March 2and April 29 and totaled 45 observation days. During this period, 102 golden eagles and 37 baldeagles were observed passing the project area. The authors noted that a high percentage of thesebirds flew along the ridge where the turbines are proposed and at heights corresponding to therotor-swept area.

Little research has been published concerning the wind turbine collision risk of eagles migratingalong linear ridge systems. Three wind facility post-construction avian mortality studies (Kernsand Kerlinger 2004; Fiedler et al. 2007; Young et al. 2009a) are cited in the Pinnacle Avian RiskAssessment as evidence of low collision risk for migrating eagles along this linear Appalachianridge. However, because of limitations in the methodologies employed or project location(discussed below), reliance on these studies may lead to a significant underestimate of risk tomigrating eagles at the proposed Pinnacle facility.

In 2003, Kerns and Kerlinger (2004) studied bird collisions and associated bird mortality at a 44-turbine wind energy facility in Tucker County, West Virginia, approximately 26 miles (42kilometers) southwest of the proposed Pinnacle site. Of the 13 rounds of carcass searchesconducted during the fall migration period, only two occurred during November, the peak monthfor golden eagle migration (Kerlinger 2009; HMANA 2008). Also, during these two rounds ofsearches (November 7 and 9 and November 14, 20-22), multi-day gaps in the field effortincreased the likelihood that any carcasses would be scavenged before discovery. Of the eightrounds of carcass searches conducted in the spring, none were conducted in March, the peakmonth for spring golden eagle migration (Kerlinger 2009; HMANA 2008). No eagle carcasseswhere found during these searches, but because of the sampling limitations noted above, theconclusion that collision risk is low is not well supported.

From April 5 to December 20, 2005, Fiedler et al. (2007) conducted weekly carcass searches at.an 18-turbine facility in Anderson County, Tennessee (approximately 370 miles or 595kilometers southwest of the Pinnacle site). Because this facility is located in the southern portion

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of the eastern golden eagle migratory range and no eagle observation or passage rate data werepresented or could be located, the relevance of this study to the proposed Pinnacle project isquestionable to the proposed Pinnacle project. The observed lack of eagle mortality at theTennessee site may simply be due to eagles not migrating past this site, or at least not in the highnumbers observed at more northern locations along the Allegheny ridge system. Without moreinformation, this study is of little use for accurately assessing collision risk at the proposedPinnacle facility.

Young, et al. (2009a) monitored avian mortality at an 82-turbine facility in Grant County, WestVirginia (approximately 10 miles or 16 kilometers south-southwest of the Pinnacle site) fromJuly 18 to October 17, 2008, and did not report any eagle fatalities. Again, golden eaglemigration through this area does not begin until late October, with the largest number of birdsmoving through in November (Kerlinger 2009; HMANA 2008). Because the study wasconducted when few, if any, migrating golden eagles would be exposed to the wind turbines, thefinding of no mortality is not particularly useful for assessing risk to this species at the proposedPinnacle facility.

Regardless of these findings, the authors of the Pinnacle study conclude that golden and baldeagles may be at risk at the Pinnacle site and that "some level of mortality may occur".Considering that bald and golden eagle numbers are increasing, we believe the site poses a highrisk of mortality to eagles over the anticipated long operational life of the project (20+ years).

The author of the Pinnacle Avian Risk Assessment also evaluated potential habitat loss causedby construction of the proposed project. He concluded the relative degree of habitat loss was alow risk because no eagle nests were observed during surveys of the project area. However, abald eagle nest was documented within 4.7 miles (8 kilometers) of the project area in 2007, andmany more nests have been documented within 20 miles (32 kilometers) of the area, particularlyto the east where new observations of nesting bald eagles are being recorded on a regular basis.If bald eagle nests are found in the vicinity of the proposed project site at any time during theconstruction or operation of the project, Pinnacle Wind Force, LLC should coordinate with theService's West Virginia Field Office to minimize disturbance and the risk of collision byfollowing the Service's Bald Eagle Management Guidelines (Service 2007, see Enclosure 1).

Bald eagles can be particularly sensitive to human activity during courtship, nest building, egglaying, incubation, the early nestling phase, and later (nestlings eight weeks through fledging).Bald eagles display varying degrees of sensitivity to humans, depending on several factors,including: visibility, duration, noise levels, extent of the area affected by the activity, priorexperiences with humans, and tolerance of the individual nesting pair (Service 2007).

An eagle migration survey has been initiated by the National Aviary, Powdermill AvianResearch Center, and several other institutions. During 2007-08, this project tracked severalgolden eagles (#s 40, 41, and 69) and a bald eagle (#65) in the general vicinity of the proposedPinnacle wind power project. Available data from the National Aviary suggest that goldeneagles migrate through a fairly narrow corridor through Pennsylvania that likely extends intoWest Virginia; as such, they consider the Allegheny Front and five adjacent ridges to the east to

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be a zone of high risk for potential impacts to golden eagles from wind turbines (Katzner et. al.2008). Peregrine falcons also are known to nest just south of the proposed Pinnacle wind powersite.

While the single year of survey data from the Pinnacle study area indicated that there were nolarge concentrations of raptors, recent analyses of raptor abundance data and collision mortalityevents indicate that abundance is not necessarily a good predictor of collision fatalities (de Lucaset. al. 2008). Other factors, such as species-specific flight behavior and morphology, weather,and topography in the vicinity of wind power facilities may be equally or more likely related todifferences in mortality rates. Additional pre- and post-construction surveys would help toassess. the risk to bald and golden eagles, and clarify whether raptor numbers and flight corridorsvary according to season and weather patterns, potentially increasing the risk under certainconditions. As a case in point, raptor studies for both the Pinnacle and New Creek wind powerprojects covered the peak of migration yet resulted in widely, different estimates of eagleabundance (Kerlinger 2009, Stantec 2008b, c). The reasons are unclear but could be related todifferences in thermals between ridgelines, seasonal variation among sites, observer differences,or other factors. These differences highlight the need for multi-year pre-construction surveys.

Migratory Bird Concerns

For a number of reasons, we believe the risk to migratory birds (including raptors) is higher thanindicated in the Pinnacle Risk Assessment. The proposed project is located along ridgelinesconsidered to be part of the Allegheny Front, a known major migration corridor for birds andbats. There are over 50 years of bird migration records from the Allegheny Front MigrationObservatory station at Bear Rocks, located approximately 130 miles (210 kilometers) south ofthe proposed Pinnacle project in the same chain of ridgelines used by birds for broad-front long-distance migration. Observations have been made at Bear Rocks every fall since 1948 bymembers of the Brooks Bird Club and reported in their quarterly journal, the Redstart. Over200,000 migrating birds have been banded at this station.

In addition, few' mortality studies have been conducted at wind power facilities on forestedridgelines in the Appalachians, similar to those conditions at the Pinnacle site. Of these studies,including ongoing studies at the Mount Storm wind power facility in West Virginia (Young et al.2009 a, b), mortality rates tend be higher than at projects in dissimilar habitat types such asagricultural fields and grasslands. The mortality rates at wind power facilities on forestedridgelines are four to six birds per tower per year compared with the zero to four birds per towerper year mortality rate in agricultural fields and grasslands (see Stantec 2008d, Appendix A,Table 3).

Furthermore, we are concerned about the cumulative impact of wind power projects in theAllegheny Front. There are two projects currently in operation (Mountaineer and NedPowerMount Storm), located within 35 miles (56 kilometers) of the proposed Pinnacle project. Theseprojects have documented mortality of birds and bats. In addition, we are aware of a number ofother proposed projects in the Allegheny Front, including the New Creek and Dan's Mountainwind power projects. We therefore believe the risk to migrating birds from the proposedPinnacle project is higher than indicated in the Risk Assessment because: 1) the proposed project

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is located in a major migration pathway, 2) mortality rates at wind power sites tend to be higheralong forested ridgelines, and 3) a number of projects are planned or operating in the AlleghenyFront. Even if the post-construction mortality of birds at the Pinnacle site were as relatively lowas estimated in the Pinnacle Avian Risk Assessment, the cumulative impact of these wind powerfacilities, when added to other bird mortality factors (collisions with buildings, moving vehicles,and power lines; or bird kills. associated with contaminant exposure and other human-causedfactors) may result in bird population declines.

Among other things, the Migratory Bird Treaty Act (MBTA, 16 U.S.C. 703-712) prohibits thetaking, killing, injuring or capture of listed migratory birds. The unauthorized taking of even onebird is legally considered a "take" under the MBTA and is a violation of the law..Bald andgolden eagles are afforded additional legal protection under the Bald and Golden EagleProtection Act (Eagle Act, 16 U.S.C.. 668). Neither the MBTA nor its implementing regulationsfound in 50 CFR Part 21 provide for the . permitting of "incidental take" of migratory birds thatmay be killed or injured by the wind turbines.

The Service carries out its mission to protect migratory birds not only through habitat andspecies management, regulatory programs, investigations and enforcement, but also throughfostering relationships with individuals and industries that proactively seek to eliminate theirimpacts on migratory birds. It is not possible under the MBTA to absolve individuals,companies, or agencies from liability if unauthorized take occurs. However, depending on thecircumstances, the Office of Law Enforcement may exercise enforcement discretion. TheService focuses its attention on those individuals, companies, or agencies that take migratorybirds with disregard for their actions and the law, especially when conservation measures orspecific recommendations regarding pre-construction surveys and post-construction monitoringare either ignored or not properly implemented. In this regard, the Service offersrecommendations at the end of this letter and we reiterate our willingness to work with you todevelop measures to avoid and minimize impacts to migratory birds, including eagles.

The Eagle Act prohibits the take of bald and golden eagles unless pursuant to regulations. In thecase of bald eagles, take can only be authorized under a permit. The Eagle Act defines the takeof an eagle to include a broad range of actions: pursue, shoot, shoot at, poison, wound, kill,capture, trap, collect, or molest or disturb. Disturb is defined in regulations found at 50 CFR22.3 as: to agitate or bother a bald or golden eagle to a degree that causes, or is likely to cause,based on the best scientific information available, (1) injury to an eagle, (2) a decrease in itsproductivity, by substantially interfering with normal breeding, feeding, or sheltering behavior,or (3) nest abandonment, by substantially interfering with normal breeding, feeding, or shelteringbehavior.

While the Service's goal is to avoid take of eagles, we recognize that take may occur despiteefforts to avoid it. Toward that end, the Service published new regulations for eagle permits onSeptember 11, 2009 (74 Federal Register 46836-46879). These new regulations becomeeffective on November 10, 2009. Because the regulations are new, it will take some time for theService and others to fully interpret their ramifications and applications. These new regulationsallow for applications for permits for the type of take anticipated at wind power facilities. Weare available to work with you to develop a full suite of avoidance, minimization, and mitigation

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options, including but not limited to consideration of alternative project locations, and featheringof blades at some turbines during peak migration and/or periods of inclement weather. Underthese new regulations, individual permits may be available to individual wind power companies.In addition, programmatic permits may be available to the wind power industry as a whole.

Bat Risk Assessment

The bat risk assessment for the proposed Pinnacle project included mist net surveys for thepresence of bats at the site (during summer and fall 2007 and spring 2008) and surveys of twonearby caves for bat usage (BHE Environmental 2008b). No Federally-listed endangered orthreatened bats were captured. The risk assessment reported no caves or portals known tosupport the endangered Indiana bat or Virginia big-eared bat within five miles (eight kilometers)of the Pinnacle project area. The risk assessment also noted the presence of 11 small Indiana bathibernacula within 40 miles (64 kilometers) of the project area. However, the authors of the RiskAssessment concluded that the risk of mortality to listed bats was low because of the low densityof listed bats near the project area, the lack of capture of listed bats during mist-net and cavesurveys, the fact that Indiana bats tend to concentrate their foraging within five miles (eightkilometers) of known hibernacula, and because a listed bat has not yet been documented to havebeen killed at an operating wind power facility.

While the Service believes the risk to listed bat species is low, we note there is still a risk ofmortality given that Indiana bats are capable of migrating long distances of over 300 miles (483kilometers) (Service 1999) and during the 20+ year operating span of the proposed project, thereis a likelihood that a listed bat may cross the blade-swept path of the turbines and be killed.Unauthorized take of just one individual of a listed species is a violation of the EndangeredSpecies Act.

The Service believes that the risk of mortality to unlisted bat species is higher than the risk tolisted bats, and could be biologically significant over time, considering cumulative impacts.Overall, the authors of the Bat Risk Assessment for the Pinnacle project conclude that becausepre-construction bat usage of the proposed Pinnacle site is relatively low,. post-construction batusage and collision mortality will also be low or "not biologically significant." This conclusionseems tenuous to us and two studies not cited in the risk assessment indicate that bat mortality,especially for unlisted bats, may likely be of concern at the Pinnacle site.

Kerns and Kerlinger (2004) studied bat collision mortality at a 44-turbine wind energy facility inTucker County, West Virginia, approximately 26 miles (42 kilometers) southwest of theproposed Pinnacle site. During 23 rounds of searches between April and November, 2003, 475bat carcasses of seven species were recovered. The estimated bat mortality rate at this facilityduring the study period was 47.3 bats/turbine (2,092 bats total).

Fiedler et al. (2007) conducted a similar study at an 18-turbine facility in Anderson County,Tennessee (approximately 370 miles or 596 kilometers southwest of the Pinnacle site but withbat use similar to. that of the Pinnacle site). Forty carcass searches were conducted betweenApril and December, 2005 and 243 bats of six species were recovered. The calculated mortalityrate was estimated to be 63.9 bats/turbine/year (1,149 bats total).

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Because no pre- or post-construction mist-net or acoustical data were available for either of thesetwo sites, we have no way of correlating bat usage rates with mortality. Other studies showingthat bat activity varies between intact, edge, and cleared forest locations (Erickson and West1996, Grindal 1 996) indicate that pre-construction bat surveys may not be especially useful foraccurately predicting bat usage of a site after forest clearing and construction. Habitatmodifications resulting from the clearing for turbine pads, access roads, and other infrastructurewill create open and edge habitat that will likely result in an increased use of the area by at leastsome bat species:

Bat mortality has been documented at all eastern wind power facilities to date. The major causeof death is thought to be a sudden drop in air pressure near the turbine blades, which causesinjury to the bat's lungs known as barotrauma (Baerwald et al. 2009). Although the respiratorysystems of birds can withstand such drops, the physiology of bat lungs does not allow for thesudden change of pressure. In addition, some bats may die from collisions with turbine blades.In particular, long distance migrants such as red bats, hoary bats, and silver-haired bats are oftenfound during post-construction mortality searches.

Although bat acoustic data were not collected at the proposed Pinnacle site, they were collectedduring 2007 and 2008 at the proposed New Creek wind power site on a forested ridgeline fivemiles (eight kilometers) away (Stantec Consulting 2008b, c). When considering these data, it isevident there is a clear risk to migratory bats due to operation of both wind power facilities. Inparticular, acoustic surveys conducted at the proposed New Creek wind power site indicatedhigh levels of bat activity in the upper air space for the long-distance migratory bats (StanteccConsulting 2008c), the species group killed most frequently in the eastern United States, andeastern pipistrelles, which have suffered relatively severe mortality effects in the northeast inassociation with white-nose syndrome. Thus these species are at a higher risk for collision withwind turbines. It is unknown whether the anticipated mortality of these bats will affect theirpopulations, though there is the potential that the cumulative effect of multiple eastern windpower facilities will reduce the overall bat populations over the life of the facilities (20 to 30years). Cumulative impacts of mortalities have been postulated to lead to substantial populationdeclines given the relatively slow rates of reproduction and long life span of bats (Kunz et al.2007a, Kunz et al. 2007b; Kuvelsky et al. 2007). In addition, other factors, such as the spread ofwhite-nose syndrome, could significantly increase the risk for cumulative impacts to bat speciespopulations in the east.

While the Service believes that the risk to Federally-listed bats through habitat modification,fragmentation, collision with turbine blades, and barotrauma is not considered high for thePinnacle project individually, the cumulative impacts of such development in conjunction withthe rapid spread of white-nose syndrome and other threats could result in local or regionalpopulation declines. White-nose syndrome has recently been confirmed in caves in PendletonCounty, south of the proposed Pinnacle wind power facility, including at least one Indiana bathibernaculum. This species, along with other Myotis species, has been shown to be severelyaffected in hibernacula in other states where hibernating bats have been infected with white-nosesyndrome. In addition, while no infected Virginia big-eared bats have been found to date,several West Virginia caves provide critical habitat for the species. Depending on the spread of

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white-nose syndrome in coming years and the susceptibility of these endangered bats to thedisease, assessments of cumulative impacts to both these species and the status of many other batspecies, could change dramatically, including possible listing of new species under theEndangered Species Act.

Higher bat activity and fatalities have been consistently related to periods of low wind speed andweather conditions typical of the passage of storm fronts (Arnett et al. 2008, Horn et. al. 2008,Reynolds 2006). Arnett et. al. (2009) found that bat fatalities were significantly reduced bychanging wind turbine cut-in speed and reducing operational hours during low wind periods.Their results were said to be similar to those of another recent study of operational curtailment(Baerwald et al. 2009), with data from both indicating a potential reduction in bat fatalities of 50percent. Arnett et al. (2009) found reductions in average nightly bat fatality ranging from 56 to92 percent with minimal total annual power output loss (< 1 percent). Data from the New Creekacoustic bat survey work supports this approach in operational curtailment as well. The riskassessment for the New Creek wind power project (Stantec Consulting 2008d) notes that aqualitative comparison of wind speed, temperature and bat activity at this and other sites withsimilar surveys suggests that bat activity levels were generally higher on nights with wind speeds< 6 meters/second (20 feet/second) . and temperatures > 14 °Centigrade (>57 °Fahrenheit). Whileadditional studies are needed to further test the effects of changes in turbine cut-in speed amongdifferent sizes and types of turbines, wind regimes, and other weather and habitat conditions onbat fatalities, these studies provide a good initial step in assessing the effectiveness andpracticality of using modifications of turbine cut-in speed based on wind regimes as a mitigativestrategy.

Summary and Recommendations

The Service believes that the weight-of-evidence approach used in the Pinnacle Risk Assessmentis an acceptable approach to determine the relative level of impact a particular stressor (i.e.,construction activities, collision) will have on a species or group. However, we believe the riskto some groups is higher than determined in the Risk Assessment. In particular we are mostconcerned about the mortality risk to eagles and unlisted bats from the proposed Pinnacle WindPower Project, as well as the cumulative effects of multiple wind power projects and otherstressors on populations of eagles, other birds, and bats.

It is important for the Service, Pinnacle Wind Force, LLC, and others to work together to gatherthe information needed to determine feasible and effective methods to reduce collision andmortality risk to birds and bats from wind power projects. Based upon the above analysis, weoffer the following recommendations to avoid and reduce anticipated impacts to birds and batsand to document any mortality events or changes to the species populations and diversity due toconstruction and operation of the proposed Pinnacle wind power facility. Theserecommendations are based on currently available best scientific information. As newinformation becomes available, we reserve the right to modify these recommendations.

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Pre-Construction Recommendations1) Reduce the amount of forest removal as much as possible to reduce impacts to forest

species, including bats and birds. Implement seasonal clearing restrictions that protectIndiana bats and nesting birds.

2) Protect forest habitat off-site to compensate for forest clearing and fragmentation on-site.3) Avoid impacts to talus and rocky outcrop areas that may be used as roost sites by small-

footed bats and other sensitive species.4) Follow the guidelines in the Avian Protection Plan (APLIC and Service 2005) to avoid

and reduce bird collisions with overhead lines or guy wires.Post-Construction Recommendations

1) Post-construction mortality monitoring and adaptive management should occur over theoperational life of the project. There should be at least three years of intensivemonitoring at the beginning of operation. A longer period of intensive monitoring maybe needed. Reduced frequency and/or intensity of monitoring may be possible at laterstages if early studies document effective operational parameters that significantly reducebird and bat mortality. Once effective measures are identified, periodic monitoringshould continue throughout the operational life to continue to document that the measuresare working as planned. Monitoring of bird and bat mortality should occur during spring,summer, and fall seasons. In addition, winter searches should focus on eagle mortality.

2) Pinnacle Wind Force, LLC should coordinate with the Service and WVDNR on study .plans and monitoring prior to initiation of the monitoring.

3) Post-construction assessments should move beyond counts of dead bats and birds in orderto identify effective operational parameters that avoid and minimize bird and batmortality. Studies should investigate if birds and bats are attracted to turbines, and howbird and bat activity and mortality varies with wind speed, direction, persistent weatherevents, and perhaps other factors.

4) We recommend the use of radar and other monitoring techniques to assess the numbers ofbirds and bats that are actually flying low enough to be exposed to risk of mortality fromwind turbines. We also recommend that the proportion of birds and bats that aresuccessful in passing through the turbine's blade-swept area or that change their flighttrajectory to completely avoid the wind turbines be determined. These studies should beconducted during all local climatic conditions and all pertinent daily periods. Changes inbehavior and mortality, as well as methods for predicting mortality events should bereported to the Service.

5) The monitoring plan should include a robust adaptive management component thatdescribes the studies to be conducted, anticipated outcomes (hypotheses to be tested), anda subsequent series of responses addressing those outcomes. Monitoring should beconducted to determine if the selected responses actually result in a reduction. of fatalities.Adaptive management trials should begin on some of the turbines in Year 1 of operation.

6) The operation of the facility should be conducted in order to reduce anticipated bird andbat mortality. In particular, there is mounting evidence that bat activity and mortalityoccur primarily at low wind speeds. Studies should be conducted on the effectiveness ofmodifying project operations to reduce anticipated bird and bat mortality (such asmodifying cut-in speeds, and feathering or stopping blades during the peak of migrationor during high-risk weather events). To facilitate data collection in a consistent manner

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at multiple wind power sites, we recommend that Pinnacle Wind Force, LLC participatein studies similar to the ongoing curtailment study at the Casselman wind power projectin Somerset County, Pennsylvania (Arnett et al. 2009).

7) Mortality searches should use dogs to improve detection rates in medium and low-visibility habitats (Arnett 2006).

8) Fatality estimates should include complex estimators to account for project sitevariations, particularly for scavenger activity (Huso 2008); daily searches at some towersites, as well as weekly searches at other towers (Huso 2008, Kerns et al. 2005); largesample sizes of appropriate carcasses (Arnett et al. 2008, Huso 2008); and corrections forhabitat variation (Arnett et al. 2008).

9) Due diligence must be practiced in identifying carcasses. Photographs of all bird and batcarcasses should be taken. Except for bat species of the genus Myotis, other carcassesmay be used for determination of scavenging rates and searcher efficiency; however,small tissue samples (such as a feather, toe clip, or small wing punch) should be taken ifthere are questions about identification. All Myotis bat carcasses should be sent to theWVDNR with the researcher's determination of genus and species, date of collection,and turbine number where the carcass was collected. Unidentified bat carcasses shouldbe specially marked with a request for identification from WVDNR bat experts. ShouldWVDNR staff be unable to conclusively identify these carcasses, and/or conclusivelydetermine through process of elimination that the unidentified carcasses are notFederally-listed endangered or threatened bat species, then Pinnacle Wind Force, LLCshould provide funds to the WVDNR for genetic testing at a lab selected by WVDNRand the Service.

10) Survey reports should be submitted to the Service's West Virginia Field Office andWVDNR after each study season and annually by December 31.

11) To help predict raptor impacts, we recommend that Pinnacle Wind Force, LLC fundresearch on raptor migration patterns in the area, including bald and golden eagles. Thiscould include modeling raptor migration pathways along the Allegheny Front orcontributing to ongoing radio telemetry studies by the National Aviary.

12) If nesting bald eagles are found within the project area at any time during the operationallife of the project, then the Service's Bald Eagle Management Guidelines (Service 2007)should be followed to avoid disturbance during critical nesting times. We have excerptedpertinent portions of the guidelines for your reference (Enclosure' 1). Due to the risk ofbald eagle strikes once a nest has been established, the Service may recommend that windturbine operation cease if a nest is found within 1320 feet (400 meters) of a turbine.Additional management considerations may be recommended if it appears that thebreeding bald eagles are foraging along or adjacent to the turbine string.

13) If a bald or golden eagle, or a Federally-listed threatened or endangered species is foundduring a mortality search, then Pinnacle Wind Force, LLC will notify the Service's WestVirginia Field Office and WVDNR within 24 hours and discuss how to modifyoperations to avoid impacts in the future.

14) If it is not possible to avoid impacts to Federally-listed species or to bald and goldeneagles, then Pinnacle Wind Force, LLC may pursue incidental take permits under theEndangered Species Act and Eagle Act, respectively. Pinnacle Wind Force, LLC mayalso. apply for such peiuiits prior to construction.

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13Mr. Paul Kerlinger and Mr. Mike SponslerSeptember 30, 2009

We look forward to working with Pinnacle Wind Force, LLC and its consultants to implementthe recommendations made above. We appreciate the opportunity to provide informationrelative to wildlife issues, and thank you for your interest in these resources. If you have anyquestions, please contact Laura Hill at 304-636-6586, Ext. 18 or laura hillCafws.gov .

Sincerely,

Deborah CarterField Supervisor

Enclosure

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cc:RO: Keith Hastie, Diane Lynch, Dave RothsteinWVDNR: Roger AndersonPinnacle Wind Force, LLC: David Friend, 10592 Perry Highway, #210, Wexford, PA 15090Project FileReader FileES: WVFO:LHill:skd:9/30/2009Filename: P:\Wind Power\Pinnacle\Pinnacle Avian and Bat Comments (Sep 30 09).doc

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References

Arnett, E.B. 2006. A preliminary evaluation on the use of dogs to recover bat fatalities at windenergy facilities. Wildlife Society Bulletin 34:1440-1446.

Arnett, E.B., W.K. Brown, W.P. Erickson, J.K. Fiedler, B.L. Hamilton, T.H. Henry, A. Jain,G.D. Johnson, J. Kerns, R.R. Koford, C.P. Nicholson, T.J. O'Connell, M.D. Piorkowski,and R.D. Takersley, Jr. 2008. Patterns of bat fatalities at wind energy facilities in NorthAmerica. Journal of Wildlife Management 72:61-78.

Arnett, E. B., M. Schirmacher, M. M. P. Huso, and J. P. Hayes. 2009. Effectiveness of changingwind turbine cut-in speed to reduce bat fatalities at wind facilities. An annual reportsubmitted to the Bats and Wind Energy Cooperative. Bat Conservation International.Austin, Texas. 45 pp.

Avian Power Line Interaction Committee (APLIC) and U.S. Fish and Wildlife Service. 2005.Avian Protection Plan (APP) Guidelines. Edison Electric Institute APLIC and U.S. Fishand Wildlife Service joint document. 84 pp.

Baerwald, E. F., J. Edworthy, M. Holder, and R.M.R. Barclay. 2009. A large-scale mitigationexperiment to reduce bat fatalities at wind energy facilities. Journal of WildlifeManagement 73:1077-1081.

BHE Environmental 2009a. Habitat characterization and assessment of rare, threatened, andendangered species for the Pinnacle Wind Farm, Mineral County, West Virginia.Prepared for: Pinnacle Wind Force, LLC. 49 pp.

BHE Environmental 2009b. Bat risk assessment: Pinnacle Wind Farm, Mineral County, WestVirginia. Prepared for: Pinnacle Wind Force, LLC. 96 pp.

Butchkoski, C. M. 2007. Indiana bat foraging habitat study. Pennsylvania Game Commission.Unpublished report.

de Lucas, M., G.F.E. Janss, D.P. Whitfield, and M. Ferrer. 2008. Collision fatality of raptors inwind farms does not depend on raptor abundance. Journal of Applied Ecology 45:1695-1703.

Erickson, J.L. and S.D. West. 1996. Managed forests in the Western Cascades: The effects ofseral stage on bat habitat use pattenis. Bats and Forests Symposium, October 19-21,1995. Working Paper 23/1996. British Columbia Ministry of Forests, Victoria, Canada.

Fiedler, J.K., T.H. Henry, R.D. Tankersley, and C.P. Nicholson. 2007. Results of bat and birdmortality monitoring at the expanded Buffalo Mountain windfarm, 2005. TennesseeValley Authority.

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September 30, 2009

Grindal, S.D. 1996. Habitat use by bats in fragmented forests. Bats and Forests Symposium,October 19-21, 1995. Working Paper 23/1996. British Columbia Ministry of Forests,Victoria, Canada.

HMANA. 2008. Hawk Migration Association of North America. www.hmana.org

Horn, J.W., E.B. Arnett, and T.H. Kunz. 2008. Behavioral responses of bats to operating windturbines. Journal of Wildlife Management 72:123-132.

Huso, M. 2008. A comparison of estimators of bat (and birdO mortality at wind powergeneration facilities. Bats and wind Energy Cooperative Workshop, Austin, Texas.January 8-10. Available at www.energetics.com/BWECWorkshop2008/agenda.html.

Katzner, T.D. Brandes, M. Lanzone, T. Miller, and D. Ombalski. 2008. Raptors and windenergy development in the Central Appalachians: where we stand on the issue. NationalAviary Policy Statement — Wind Power.

Kerlinger, P. 2009. Avian risk assessment for the Pinnacle wind power project, Mineral County,West Virginia. Prepared for Pinnacle Wind Force, LLC. 53 pp.

Kerns, J., W.P. Erickson, and E.B. Arnett. 2005. Chapter 3. Bat and bird fatality at wind energyfacilities in Pennsylvania and West Virginia. Pages 24-95 in Arnett, E.B. (ed.),Relationship between bats and wind turbines in Pennsylvania and West Virginia: anassessment of fatality search protocols, patterns of fatality, and behavioral interactionswith wind turbines.

Kerns, J. and P. Kerlinger. 2004. A study of bird and bat collision fatalities at the MountaineerWind Energy. Center, Tucker County, West Virginia: Annual report for 2003. Preparedfor: FPL Energy and Mountaineer Wind Energy Center Technical Review Committee.

Kunz, T.H., E.B. Arnett, W.P. Erickson, A.R. Hoar, G.D. Johnson, R.P. Larkin, M.D. Strickland,R.W. Thresher, and M.D. Tuttle. 2007a. Ecological impacts of wind energydevelopment on bats: questions, research needs, and hypotheses. Frontiers in Ecologyand the Environment 5:315-324.

Kunz, T.H., E.B. Arnett, B.P. Cooper, W.P. Erickson, R.P. Larkin, T. Mabee, M.L. Morrison,M.D.. Strickland, and J.M. Szewczak. 2007b. Assessing impacts of wind-energydevelopment on nocturnally active birds and bats: A guidance document. Journal ofWildlife Management 71:2449-2486.

Kuveleski, W.P., Jr., L.A. Brennan, M.L. Morrison, K.K. Boydston, B.M. Ballard, and F.C.Bryant. 2007. Wind energy development and wildlife conservation: Challenges andopportunities. Journal of Wildlife Management 71:2487-2498.

Mabee, T.J., B.A. Cooper, J.H. Plissner, and D.P. Young. 2006. Nocturnal bird.migration overan Appalachian ridge at a proposed wind power project. Wildlife Society Bulletin 34(3).

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Nicholson, C.P. 2001. Buffalo Mountain windfarm bird and bat mortality monitoring report:October 2000 — September 2001. Tennessee Valley Authority, Knoxville, TN.

Nicholson, C.P. 2002. Buffalo Mountain windfarm bird and bat mortality monitoring report:October 2001 — September 2001. Tennessee Valley Authority, Knoxville, TN.

Reynolds, D.S. 2006. Monitoring the potential impacts of a wind development site on bats inthe northeast. Journal of Wildlife Management 70(5):1219-1227.

Stantec Consulting. 2008a. New Creek Mountain bird and bat risk assessment: a weight-of-evidence approach to assessing risk to birds and bats at the proposed New Creekmountain project, West Virginia. Prepared for: AES New Creek, LLC, Arlington, VA.105 pp.

Stantec Consulting. 2008b. Fall 2007 bird and bat migration survey report. Visual, radar, andacoustic bat surveys for the New Creek Mountain project, West Virginia. Prepared for:AES New Creek, LLC, Arlington, VA. 73 pp.

Stantec Consulting. 2008c. Spring, summer, and fall 2008 bird and bat migration survey report.Visual, radar, and acoustic bat surveys for the New Creek Mountain project, WestVirginia. Prepared for: AES New Creek, LLC, Arlington, VA. 103 pp.

Stantec Consulting. 2008d. Radar and acoustic bird and bat survey report — Fall 2004, Spring2005, and Fall 2005 surveys for the proposed Dan's Mountain wind project in AlleganyCounty, Maryland. Prepared for: Dan's Mountain Wind Force, LLC.

U.S. Fish and Wildlife Service. 2007. National Bald Eagle Management Guidelines. U.S. Fishand Wildlife Service, Washington, D.C. 25 pp.

Woodlot Alternatives. 2005. A spring 2005 radar and acoustic survey of bird and bat migrationat the proposed Dan's Mountain Wind project in Frostburg, MD. Report prepared for:U.S. Wind Force, LLC.

Young, D.P. Jr., W.P. Erickson, K. Bay, S. Nomani, and W. Tidhar. 2009a. Mount Storm windenergy facility, Phase 1 post-construction avian and bat monitoring, July-October 2008.Prepared by WEST, Inc. for NedPower, Mount Storm, LLC, Houston, TX. 46 pp +appendices

Young, D.P. Jr., K. Bay, S. Nomani, and W. Tidhar. 2009b. NedPower Mount Storm windenergy facility, post-construction avian and bat monitoring, March-June 2009. Preparedby WEST, Inc. for NedPower, Mount Storm, LLC, Houston, TX. 51 pp.

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Enclosure 1. Bald eagle status and distribution in West Virginia, responses todisturbances, and guidelines for projects near active nests.

The bald eagle was recently delisted and removed from the List of Federally-threatened andEndangered Species. However, the bald eagle is still protected under the Bald and Golden EagleProtection Act and the Migratory Bird Treaty Act..

Known Distribution of Bald Eagles in West Virginia

Winter Habitat: Throughout the entire state.

Active nest sites: Grant, Hampshire, Hancock, Hardy, Jefferson, Mineral, Morgan, Pendleton,Pocahontas, and Taylor counties.

This information is adapted from the Service's National Bald Eagle Management Guidelines(2007). The Guidelines provide additional information about bald eagles and managementrecommendations.

Table 1. Nesting Bald Eagle Sensitivity to Human Activities

Phase Activity

Sensitivity toHumanActivity Comments

Courtshipand NestBuilding

Most sensitiveperiod; likely torespondnegatively

Most critical time period. Disturbance is manifestedin nest abandonment. Bald eagles in newlyestablished territories are more prone to abandonnest sites.

IIEgglaying

Very sensitiveperiod

Human activity of even limited duration may causenest desertion and abandonment of territory for thebreeding season.

III

Incubationand earlynestlingperiod (upto 4weeks)

Very sensitiveperiod

Adults are less likely to abandon the nest near andafter hatching. However, flushed adults leave eggsand young unattended; eggs are susceptible tocooling, loss of moisture, overheating, andpredation; young are vulnerable to elements.

IVNestlingperiod ,4to 8 weeks

Moderatelysensitive period

Likelihood of nest abandonment and vulnerability ofthe nestlings to elements somewhat decreases.However, nestlings may miss feedings, affectingtheir survival.

V

Nestlings8 weeksthroughfledging

Very sensitiveperiod

Gaining flight capability, nestlings 8 weeks andolder may flush from the nest prematurely due todisruption and die.

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If agitated by human activities, eagles may inadequately construct or repair their nest, may expendenergy defending the nest rather than tending to their young, or may abandon the nest altogether.Activities that cause prolonged absences of adults from their nests can jeopardize eggs or young.Depending on weather conditions, eggs may overheat or cool too much and fail to hatch.Unattended eggs and nestlings are subject to predation. Young nestlings are particularly vulnerablebecause they rely on their parents to provide warmth or shade, without which they may die as aresult of hypothermia or heat stress. If food delivery schedules are interrupted, the young may notdevelop healthy plumage, which can affect their survival. In. addition, adults startled whileincubating or brooding young may damage eggs or injure their young as they abruptly leave the nest.Older nestlings no longer require constant attention from the adults, but they may be startled by loudor intrusive human activities and prematurely jump from the nest before they are able to fly or carefor themselves. Once fledged, juveniles range up to mile from the nest site, often to a site withminimal human activity. During this period, until about six weeks after departure from the nest, thejuveniles still depend on the adults to feed them.

Disruption, destruction, or obstruction of roosting and foraging areas can also negatively affect baldeagles. Disruptive activities in or near eagle foraging areas can interfere with feeding, reducingchances of survival. Interference with feeding can also result in reduced productivity (number ofyoung successfully fledged). Migrating and wintering bald eagles often congregate at specific sitesfor purposes of feeding and sheltering. Bald eagles rely on established roost sites because of theirproximity to sufficient food sources. Roost sites are usually in mature trees where the eagles aresomewhat sheltered from the wind and weather. Human activities near or within communal roostsites may prevent eagles from feeding or taking shelter, especially if there are not other undisturbedand productive feeding and roosting sites available. Activities that permanently alter communalroost sites and important foraging areas can altogether eliminate the elements that are essential forfeeding and sheltering eagles.

The numerical distances for buffers shown in Table 2 are the closest the activity should be conductedrelative to the nest.

Table 2: Buffer requirements for activities that entail permanent landscape alterations thatmay result in bald eagle disturbance. These requirements apply to active bald eagle nests.

If there is no similar activitywithin 1 mile of the nest

If there is similar activity closerthan 1 mile from the nest

If the activity willbe visible from thenest

660 feet (200 km). Landscapebuffers are recommended.

660 feet (200 km), or as close asexisting tolerated activity of similarscope. Landscape buffers arerecommended.

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If there is no similar activitywithin 1 mile of the nest

If there is similar activity closerthan 1 mile from the nest

If the activity willnot be visible fromthe nest

330 feet (100 km). Clearing,external construction, andlandscaping between 330 feet(100 km) and 660 feet (200 km)should be done outside breedingseason.

330 feet (100 km), or as close asexisting tolerated activity of similarsco p e. Clearing , externalconstruction and landscaping within660 feet (200 kn) should be doneoutside breeding season.