Wind Power: Impacts on Wildlife and Government Responsibilities for Regulating Development and Protecting Wildlife
Published: 2005-09-16T00:00:00

Fast Facts:

Highlights:
section_title: Why GAO Did This Study
paragraphs: Wind power has recently experienced dramatic growth in the United States, with further growth expected. However, several wind power-generating facilities have killed migratory birds and bats, prompting concern from wildlife biologists and others about the species affected, and the cumulative effects on species populations. GAO assessed (1) what available studies and experts have reported about the impacts of wind power facilities on wildlife in the United States and what can be done to mitigate or prevent such impacts, (2) the roles and responsibilities of government agencies in regulating wind power facilities, and (3) the roles and responsibilities of government agencies in protecting wildlife. GAO reviewed a sample of six states with wind power development for this report.
section_title: What GAO Found
paragraphs: The impact of wind power facilities on wildlife varies by region and by species. Specifically, studies show that wind power facilities in northern California and in Pennsylvania and West Virginia have killed large numbers of raptors and bats, respectively. Studies in other parts of the country show comparatively lower levels of mortality, although most facilities have killed at least some birds. However, many wind power facilities in the United States have not been studied, and, therefore, scientists cannot draw definitive conclusions about the threat that wind power poses to wildlife in general. Further, much is still unknown about migratory bird flyways and overall species population levels, making it difficult to determine the cumulative impact that the wind power industry has on wildlife species. Notably, only a few studies exist concerning ways in which to reduce wildlife fatalities at wind power facilities. Regulating wind power facilities is largely the responsibility of state and local governments. In the six states GAO reviewed, wind power facilities are subject to local- or state-level processes, such as zoning ordinances to permit the construction and operation of wind power facilities. As part of this process, some agencies require environmental assessments before construction. However, regulatory agency officials do not always have experience or expertise to address environmental and wildlife impacts from wind power. The federal government plays a minimal role in approving wind power facilities, only regulating facilities that are on federal lands or have some form of federal involvement, such as receiving federal funds. In these cases, the wind power project must comply with federal laws, such as the National Environmental Policy Act, as well as any relevant state and local laws. Federal and state laws afford generalized protections to wildlife from wind power as with any other activity. The U.S. Fish and Wildlife Service (FWS) is the primary agency tasked with implementing wildlife protections in the United States. Three federal laws--the Migratory Bird Treaty Act, the Bald and Golden Eagle Protection Act, and the Endangered Species Act--generally forbid harm to various species of wildlife. Although significant wildlife mortality events have occurred at wind power facilities, the federal government has not prosecuted any cases against wind power companies under these wildlife laws, preferring instead to encourage companies to take mitigation steps to avoid future harm. All of the six states GAO reviewed had statutes that can be used to protect some wildlife from wind power impacts; however, similar to FWS, no states have taken any prosecutorial actions against wind power facilities where wildlife mortalities have occurred.

section_title: Letter
paragraphs: The production of wind power, a renewable energy source, has recently  experienced dramatic growth in the United States, although it still  generates less than 1 percent of the electricity used in this country. Wind  power-generating facilities were first built in California about 25 years ago.  Now wind power facilities can be found in over 30 states, and the industry  is expected to continue to grow rapidly. The vast majority of wind power  facilities are located in just 10 western and midwestern states; most are on  nonfederal land. Development has slowly made its way east and is  currently being pursued along the ridge tops of the Appalachian Mountains  in Maryland, Pennsylvania, Virginia, and West Virginia. Once thought to  have practically no adverse environmental effects, it is now recognized that  wind power facilities can have adverse impacts—particularly on wildlife,  and most significantly on birds and bats.
Large numbers of birds and bats are believed to follow and cross through  many parts of the United States, including along mountain ridges, during  their seasonal migrations. Consequently, wind power projects located in  these areas could potentially impact these species. At wind  power-generating facilities in Appalachia and California, wind turbines  have killed large numbers of migratory birds and bats. Wind power  facilities may also have other impacts on wildlife through alterations of  habitat. Habitat destruction and modification is a leading threat to the  continued survival of wildlife species in the United States.
In this context, we assessed (1) what available studies and experts have  reported about the impacts of wind power facilities on wildlife in the  United States and what can be done to mitigate or prevent such impacts,  (2) the roles and responsibilities of government agencies in regulating wind  power facilities, and (3) the roles and responsibilities of government  agencies in protecting wildlife.
To address these objectives, we reviewed major scientific studies and  reports on direct impacts from wind power on avian species and other  wildlife (we did not assess indirect impacts, such as habitat impacts). We  interviewed experts from the Department of the Interior’s U.S. Fish and  Wildlife Service (FWS), state agencies, academia, industry, and  conservation groups and obtained their views on these studies and reports.  We also reviewed a nonprobability sample of six states with wind power  development—California, Minnesota, New York, Oregon, Pennsylvania,  and West Virginia. We selected these states to reflect a range in installed  wind generating capacity, regulatory processes, history of wind power  development, and geographic distribution and to reflect our requesters’  interests. We identified and reviewed relevant federal, state, and local laws  and regulations. In addition, we interviewed federal, state, and local  officials who were responsible for implementing related programs. More  information about the objectives, scope, and methodology of our  evaluation is presented in appendix I. We conducted our work between  December 2004 and July 2005 in accordance with generally accepted  government auditing standards, including an assessment of data reliability  and internal controls.
subsections: section_title: Background
paragraphs: The energy used to generate our nation’s electricity comes from many  different sources. Currently, most electricity in the United States is  generated with fossil fuel and nuclear technologies—coal (52 percent),  nuclear (20 percent), natural gas (16 percent), and oil (3 percent). Fossil  fuels are considered nonrenewable because they are finite and will  eventually dwindle or become too expensive or environmentally damaging  to retrieve. Wind, however, is one of several sources of energy known as  renewable energy. Other forms of renewable energy sources include  sunlight (photovoltaics), heat from the sun (solar thermal), naturally  occurring underground steam and heat (geothermal), plant and animal  waste (biomass), and water (hydropower).
To reduce our dependence on nonrenewable energy sources, the United  States has promoted the development of renewable resources, such as  wind. A key federal program supporting the development of such sources is  the federal production tax credit established by the Energy Policy Act of  1992.This law provides a tax credit for electricity generated by renewable  energy sources, such as wind turbines. The Economic Recovery Tax Act of  1981 provides an additional incentive for wind power growth. In some  cases, this law allows a 5-year depreciation schedule for renewable energy  systems. In conjunction with the tax credit, this accelerated depreciation  allows an even greater tax break for renewable energy projects, such as  wind projects, that have high initial capital costs.
Some states also provide incentives for wind power development. One of  the strongest drivers is a renewable portfolio standard. Generally, a  renewable portfolio standard requires utilities operating in a state to  acquire a minimum amount of their electricity supply from renewable  energy sources. As of June 2005, 18 states had some form of renewable  power requirements capable of being met by wind power. Other common  types of incentives for renewable energy development provided by several  state and local governments are income tax incentives and property and  sales tax exemptions. Many states provide more than one type of incentive.  In addition, 25 states have statewide wind working groups that are funded  (at least partially) through grants from the Department of Energy (DOE).  The purpose of these working groups is to promote more widespread  development of wind power.
These federal and state programs have helped spur significant wind power  development in the last 5 years. At the end of 2004, the total installed  capacity from wind power in the United States was 6,740 megawatts (MW),  or enough capacity to meet the electricity demand of between 1.5 and 2.0  million average American households (see fig. 1).
Between January 2000 and December 2004, installed electric-generating  capacity more than doubled, adding over 4,200 MW of capacity. Although  wind power generates less than 1 percent of the nation’s electricity, with an  average annual growth rate of over 24 percent, it is the fastest growing  source of electricity generation on a percentage basis.  Because wind  energy is a function of wind speed, the best locations for turbines are areas  that have frequent strong winds to turn the blades of the power-generating  turbines. See figure 2 for areas of the United States with high wind  potential.
According to DOE, 36 of the 48 continental states have wind resources that  would support utility-scale wind power projects (i.e., projects that generate  at least 1 MW of electric power from 1 or more turbines annually for sale to  a local utility). A DOE goal for wind power is to generate 5 percent of the  electricity generated in the United States by 2020; the American Wind  Energy Association has a similar goal. To reach this goal, the association  estimates that about 100,000 MW of installed capacity will be  needed—approximately 15 times the current installed capacity. On the  basis of the average MW size of wind turbines commonly being installed  today (1.5 MW), more than 62,000 additional turbines will need to be added  to the existing 16,000 turbines already constructed in the United States to  meet such a goal.
Most of the wind power development in the United States has occurred in  10 western and midwestern states—California, Colorado, Iowa, Minnesota,  New Mexico, Oklahoma, Oregon, Texas, Washington, and Wyoming. In fact,  these 10 states have over 90 percent of the total installed wind power  capacity nationwide. Only recently have developers begun to build wind  energy facilities in the eastern United States. As shown in figure 2, wind  power potential in this geographic area is best along mountain ridges,  primarily the Appalachian Mountains, and along the coast of the  northeastern United States.
Wind power is considered a “green” technology because, unlike fossil fuel  power plants, it does not produce harmful emissions, such as carbon  dioxide, nitrogen oxides, sulfur dioxide, mercury, and particulate matter,  which can pose human health and environmental risks such as acid rain.  However, it is now recognized that wind power facilities can adversely  affect the environment in other ways, specifically in impacting wildlife  such as birds and bats. Wind power facilities located in migratory pathways  or important habitats may harm the wildlife living or passing through the  area by killing or injuring them or by disrupting feeding or breeding  behaviors. But wind power is not alone in its impacts on wildlife. Millions,  or perhaps billions, of wildlife are killed every year in the United States  through a myriad of human activities. While sources of bat mortality are  not as well known, FWS estimates that some of the leading sources of bird  mortality, per year, are collisions with building windows—97 million to 976  million bird deaths, collisions with communication towers—4 million to 50  million bird deaths, poisoning from pesticides—at least 72 million birds,  and attacks by domestic and feral cats—hundreds of millions of bird  deaths. Human activities also result in the destruction or modification of  wildlife habitat; habitat loss and fragmentation are leading threats to the  continued survival of many species.
section_title: Studies Show Wind Power Facility Impacts on Wildlife Vary, Although Notable Gaps in the Literature Remain and Few Studies Address Mitigation
paragraphs: Recent studies and interviews with experts reveal that the impacts of wind  power facilities on birds and other wildlife vary by region and by species.  Specifically, studies showing raptor mortality in California and bat  mortality in Appalachia have elicited concerns from scientists,  environmental groups, and regulators because of the large number of kills  in these areas and the potential cumulative impact on some species. Thus  far, documented bird and bat mortality from wind power in other parts of  the country has not occurred in numbers high enough to raise concerns.  However, gaps in the literature make it difficult to develop definitive  conclusions about the impacts of wind power on birds and other wildlife.  Notably, only a few studies have been conducted on strategies to address  the potential risks wind power facilities pose to wildlife.
subsections: section_title: Wildlife Mortality Varies by Region and by Species
paragraphs: Our review of the literature and discussions with experts revealed that,  thus far, concerns over direct impacts to wildlife from wind power facilities  have been concentrated in two geographic areas—northern California and  Appalachia. (For a discussion on how we selected these studies, see app.  I.) While bird and bat kills have been documented in many locations,  biologists are primarily concerned about mortality in these two regions  because of the numbers of wildlife killed and the species affected.
subsections: section_title: Studies Have Found Large Numbers of Raptors Killed by Wind Turbines in California
paragraphs: Wind power facilities in northern California, specifically in the Altamont  Pass Wind Resource Area about 50 miles east of San Francisco, have been  responsible for the deaths of numerous raptors, or birds of prey, such as  hawks and golden eagles, and, as a result, these deaths have elicited  concern from wildlife protection groups, biologists, and regulators. Studies  conducted in the last two decades have documented large numbers of  raptor deaths in this area. One study in our review found estimates as high  as over 1,000 raptor deaths per year. Such large numbers of raptor kills due  to wind power are not seen elsewhere in the United States. A 2001  summary that examined raptor mortality rates from studies in 10 states  estimated that over 90 percent of the raptors killed annually in the United  States by wind power turbines occurred in California.
Several unique features of the wind resource area at Altamont Pass  contribute to the high number of raptor deaths. First, California was the  first area to develop wind power in significant numbers and thus has some  of the oldest turbines still in operation in the United States. Older turbines  produce less power per turbine, so it took many turbines to produce a  certain level of energy; today, newer facilities producing the same amount  of energy would have much fewer turbines. For example, Altamont Pass  has over 5,000 wind turbines—many of which are older models—whereas,  newer facilities generally have significantly fewer turbines (see figs. 3 and  4). Some experts told us that the sheer number of turbines in Altamont  Pass has been a major reason for the high number of fatalities in the area.
Secondly, some scientists believe that the design of older generation  turbines, like those found in Altamont Pass, are more fatal to raptors.  Specifically, early turbines were mounted on towers 60 feet to 80 feet in  height, while today’s turbines are mounted on towers 200 feet to 260 feet in  height. Experts told us that the older turbines at Altamont Pass have blades  that reach lower to the ground, and thus can be more hazardous to raptors  as they swoop down to catch prey. Experts also reasoned that the relative  absence of raptor kills at newer facilities with generally taller turbines  supports the notion that these turbines are less lethal to raptors. Third, the  location of the wind turbine facilities at Altamont Pass may have  contributed to the high number of raptor deaths. Studies show that there  are a high number of raptors that pass through the area, as well as an  abundance of raptor prey at the base of the turbines. In addition, the  location of wind turbines on ridge tops and canyons may increase the  likelihood that raptors will collide with turbines. Some experts note that  one reason why other parts of the country may not be experiencing high  levels of raptor mortality is partly because wind developers have used  information from Altamont Pass to site new turbines in hopes of avoiding  similar situations.
section_title: Studies Have Found Large Numbers of Bats Killed by Wind Turbines in Appalachia
paragraphs: Recent studies conducted in the eastern United States in the Appalachian  Mountains have found large numbers of bats killed by wind power turbines.  A 2004 study conducted in West Virginia estimated that slightly over 2,000  bats were killed during a 7-month study at a location with 44 turbines. More  recently, a 2005 report that examined wind resource areas both in West  Virginia and Pennsylvania estimated that about 2,000 bats were killed  during a much shorter 6-week study period at 64 turbines. Lastly, a study  conducted of a small 3-turbine wind facility in Tennessee estimated that bat  mortality was about 21 bats per turbine, per year, raising concerns about  the potential impact on bats if more turbines are built in this area.
Various species of bats have been killed at these wind power facilities and  experts are concerned about impacts to bat populations if large numbers of  deaths continue. For example, one expert noted that “it is alarming to see  the number of bats currently being killed coupled with the proposed  number of wind power developments” in these areas. He explained that  bats live longer and have lower reproductive rates than birds, and,  therefore, bat populations may be more vulnerable to impacts. In addition,  there are proposals for hundreds of new wind turbines along the  Appalachian Mountains. A recent report from Bat Conservation  International estimated that if all ridge-top turbines are approved and the  mortality rates continue at their current rate, these turbines might kill tens  of thousands of bats in a single season. Although none of the bats killed by  wind power to date have been listed as endangered species, FWS—  recognizing the seriousness of the problem—has initiated a study with the  U.S. Geological Survey to study bat migration and to develop decision tools  to provide assistance in identifying locations for wind turbines and  communication towers.
section_title: Studies Show That Bird and Bat Mortality from Wind Power in Other Parts of the Country Is Comparatively Lower Than in California and Appalachia
paragraphs: Results from studies on bird and bat mortality from wind power conducted  in areas other than northern California and Appalachia have not caused the  same degree of concern as in these two locations. Our review of studies  conducted in areas other than the Appalachian Mountains showed bat  fatality rates ranging from 0 to 4.3 bats per turbine, per year—compared  with rates as high as 38 bats per turbine, per a 6-week study period, in the  Appalachian Mountains (see app. II). Raptor fatalities outside Altamont  Pass ranged from 0 to 0.07 raptors per turbine, per year, whereas, rates in  Altamont Pass ranged from 0.05 to 0.24. Our review of studies found that  overall bird fatalities from wind power ranged from 0 to 7.28 birds per  turbine, per year. In addition, a 2004 National Wind Coordinating  Committee fact sheet shows that an average of 2.3 birds per turbine, per year are killed at facilities outside of California. However, it is important to  also look at the number of turbines and the vulnerability of the species  affected when interpreting these rates. For example, the high rate of 7.28  overall bird fatalities per turbine was found at a facility of only 3 wind  turbines. Therefore, if no additional turbines are built in this area, the  overall impact to the bird populations may be minimal; whereas, a lower  fatality rate may cause impacts if there are many turbines in that particular  area. In addition, comparing study findings can be difficult because  researchers may use differing metrics and many areas of the country  remain unstudied with regard to avian and bat impacts from wind power.  While interpreting these statistics can be complicated, the experts we  spoke with agreed that outside of California and Appalachia at the current  level of wind power development, the research to date has not shown bird  or bat kills in alarming numbers.
While the studies we reviewed showed relatively low levels of mortality in  many locations, there are also indirect impacts to wildlife from wind power  facilities. For example, construction of wind power facilities may fragment  habitat and disrupt feeding or breeding behaviors. According to FWS, the  loss of habitat quantity and quality is the primary cause of declines in most  assessed bird populations and many other wildlife species. However, this  review focuses on the direct impacts of avian and bat mortality.
section_title: Several Gaps Exist in Research on Wind Power Facility Impacts on Wildlife
paragraphs: While experts told us that the impact of wind power facilities on wildlife is  more studied than other comparable infrastructure, such as  communication towers, important gaps in the research remain. First,  relatively few postconstruction monitoring studies have been conducted  and made publicly available. It appears that many wind power facilities and  geographic areas in the United States have not been studied at all. For  example, a bird advocacy group expressed concern at a recent National  Wind Coordinating Committee meeting that most of the wind projects that  have been monitored for bird impacts are in the west. The American Wind  Energy Association reports that there are hundreds of wind power facilities  currently operating elsewhere in the country. However, we were able to  locate only 19 postconstruction studies that were conducted to assess  direct impacts to birds or bats in 11 states. Texas, for example, is second  only to California in installed wind power capacity, but we were unable to  find a single, publicly available study investigating bird or bat mortality in  that state.
Lack of comprehensive data on bird and bat fatalities from wind turbines  makes it difficult to make national assessments of the impact of wind  turbines on wildlife. A 2001 analysis of studies estimated that wind turbines  in the United States cause roughly 33,000 avian deaths per year. However,  the authors noted that making projections of the potential magnitude of  wind power-related avian fatalities is problematic, in part, because of the  lack of long-term data. The authors further noted that the data collected at  older sites may not be representative of newer facilities with more modern  turbine technology. In addition, FWS considers this estimate to be a  “minimum” to “conservative” estimate due to problems of data collection  and uneven regional representation. In addition to limiting assessments of  national impacts, a lack of data on actual mortality impacts siting decisions  for new facilities. Specifically, the conclusions of postconstruction studies  are often used when making preconstruction predictions about the degree  of harm to wildlife that is likely expected from proposed facilities. If there  are no local postconstruction studies available, predictions of future  mortality at a proposed site must be based on information from studies  conducted in areas that may have different wildlife species, topography,  weather conditions, climate, soil types, and vegetative cover.
A second important research gap is in understanding what factors increase  the chances that turbines will be hazardous to wildlife. For example, it can  be difficult to discern, among other things, how the number, location, and  type of turbine; the number and type of species in an area; species  behavior; topography; and weather affect mortality and why. Drawing  conclusions about the degree of risk posed by certain factors—such as  terrain, weather, or type of turbine—is difficult because sites differ in their  combination of factors. For example, according to experts, data are  inadequate about what turbine types are most hazardous and to what  species. This is partly because most wind power facilities use only one  turbine type. Therefore, even if one facility proved more hazardous than  another, it would be difficult to attribute the difference to turbine type  alone because other variables, such as topography or migratory patterns,  are also likely to vary among the sites. Additionally, comparisons between  studies are difficult because researchers may use different study  methodologies. Therefore, even if two sites had similar bird populations,  topography, and weather characteristics but different turbines, it would be  difficult to isolate the effect of the turbine if the scientists collecting the  information used differing methodologies.
Altamont Pass, however, has the potential to allow researchers to  determine which turbines are more hazardous because it contains many  different types of turbines in one place. However, even this analysis has  been complicated by confounding variables. For example, according to  experts, at one time it was commonly thought that turbines with lattice  towers killed more birds than turbines with tubular towers in Altamont  Pass; however, some studies have reached the opposite conclusion. One  study noted that although the authors found higher mortality associated  with lattice towers, this relationship might be explained by factors such as  the fact that lattice towers were found to be in operation more frequently  than were other towers, including tubular towers, rather than the  difference in the design of the towers. Complicating matters still, some  factors may be more hazardous for some species than others. One study  found that red-tailed hawk fatalities occurred more frequently than  expected at turbines located on ridgelines than on hillsides. The authors  found the reverse to be true for golden eagles, demonstrating the difficulty  of understanding interactions between turbines and bird mortality from  bird mortality estimates alone.
A third research gap is the lack of complete and definitive information on  the interaction of bats with wind turbines. As previously noted, bats have  collided with wind turbines in significant numbers in some parts of the  United States, but scientists do not have a complete understanding  regarding why these collisions occur. Bats are known to have the ability to  echolocate to avoid collision with objects, and they have been able to avoid  colliding with comparable structures such as meteorological towers.  Therefore, their collision with wind turbines remains a mystery. The few  studies that have been conducted show that most of the kills have taken  place during the migratory season (July through September), and this  suggests that migrating bats are involved in most of the fatalities. In  addition, one study showed that lower wind speeds were associated with  higher fatality rates. However, experts admit that much remains unknown  about why bats are attracted to and killed by turbines and about what  conditions increase the chances that bats will be killed. One expert noted  that there is still very little known about bat migration in general and about  the way in which bat interactions with turbines are affected by weather  patterns. This expert further noted that there still has not been a full season  of monitoring bat mortality from which patterns can be identified.
Although scientists still do not know why bats are being killed in large  numbers by wind power turbines in some areas, several hypotheses have  been offered. One hypothesis states that the lighting on turbines attracts  insects, which in turn attracts bats, but studies have not demonstrated  differences in fatalities between lit turbines and unlit turbines. Other  hypotheses include the notions that bats may be investigating wind  turbines as potential roosting sites, that open spaces around turbines  create favorable foraging habitats, and that migrating bats do not  echolocate and thus are less able to avoid collision. One thing bat experts  agree on is the need for more research.
In addition to these research gaps regarding bird and bat interactions with  turbines, very little is known about bird and bat populations in general,  such as their size and migratory pathways. An FWS official told us that data  are available regarding the migration routes and habitat needs of only  about one-third of the more than 800 bird species that live in or pass  through the United States each year. In addition, bat researchers stressed  to us that very little is known about the pathways and behavior of  migratory bats. This lack of information, among other factors, makes it  difficult to assess the cumulative impacts from wind power on species  populations. One expert noted that many bird populations are in decline in  general and additional losses due to wind power may exacerbate this trend.  However, it is very difficult to attribute a decline in bird populations to  wind power specifically or to get good data on overall populations that  span international borders. Our literature search was only able to find one  study in the United States that examined the impact of fatalities from wind  power on a particular species population—golden eagles—and those  results have been described as relatively inconclusive, or mixed, by other  scientists. Without this kind of information, it can be difficult to determine  the appropriate public policy responses to wildlife impacts due to wind  power.
Although there are currently several gaps in the study of wind power’s  direct impacts on birds and bats, FWS and the U.S. Geological Survey have  recently initiated a study of bird and bat migration behaviors to address  some of these data gaps. This study will use radar technology to  characterize daily and seasonal movements and habitat and landform  associations of migrating birds and bats, and will seek to develop decision  support tools to provide assistance in identifying locations for wind  turbines and communication towers. In addition, Congress has  appropriated funds for a National Academy of Sciences study on the  environmental impacts of wind power development in the Mid-Atlantic  Highlands that will include developing criteria for the siting of wind  turbines in this area. Finally, the Bats and Wind Energy Cooperative, a  partnership of Bat Conservation International, the American Wind Energy  Association, FWS, and the National Renewable Energy Laboratory,  continues to sponsor research on bats and wind turbines focusing on  acoustic deterrence methods and pre- and postconstruction risk  assessment at a planned wind farm in the Appalachian region.
section_title: Few Studies Have Been Conducted on Mitigation Measures
paragraphs: Overall, there is much to be learned about mitigation strategies for  reducing impacts from wind power facilities on birds and bats, and some  strategies that once looked promising are now proving ineffective.  Specifically, we found that relatively few studies have examined strategies  for reducing the potential impacts of wind power on birds and bats. Some  of these studies were based on information collected from birds in a  laboratory setting, and, therefore, their conclusions still need to be verified  by conducting studies at actual wind power facilities. One study examined  the idea of addressing motion smear—the inability of birds to see moving  blades—by painting turbine blades to make them more visible. This study  indicated that color contrast was a critical variable in helping birds to see  objects like moving turbine blades and recommended painting stripes on  blades as a way to test whether this could be an effective deterrent. Some  developers adopted this strategy; however, a recent study found that  turbines with painted blades were ineffective in reducing bird kills.  Another laboratory-based study tested bird reactions to noise and sound  pressure and suggested that whistles could make blades more audible to  birds, while making no measurable contribution to overall noise levels.  However, the authors of this study made no predictions about changes in  bird flight in response to hearing the noise and noted that field tests would  be required to test this hypothesis.
Although there have been relatively few laboratory-based experiments on  mitigation strategies, some strategies have already been attempted in  Altamont Pass. A recent 4-year study conducted by the California Energy  Commission in Altamont Pass tested some of these mitigation efforts  attempted by industry and suggested possible future mitigation strategies.  This study found that some of the strategies adopted by industry, such as  perch guards on turbines and rodent control programs that reduce prey  availability, were ineffective in reducing kills. Another study compared the  differences between turbines painted with ultraviolet reflectant or  nonultraviolet reflectant to see whether one would act as a visual  deterrent, but the study found no evidence of a difference in mortality  between the two treatments.
While there is less than adequate information on the effectiveness of  mitigation strategies from existing scientific research, the experts with  whom we spoke were hopeful about several strategies on the basis of their  experience in the field. Some of these experts noted that because birds  have been found to collide with electrical wires, wind facilities should bury  their transmission lines under ground and avoid using guywires on their  meteorological towers; such fixes have generally been adopted. Although  some studies have shown that there are no differences in mortality rates for  lit turbines versus unlit turbines, some experts argue that, regardless, it is  best to use low lighting to avoid attracting birds that migrate at night. In  addition, researchers recommended that sodium vapor lights should never  be used at or near wind power facilities because they have commonly been  shown to attract birds to other structures. They noted that the largest  number of birds killed at one time near wind turbines was found adjacent  to sodium lights after a night of dense fog. No fatalities have been  discovered near these turbines since the lights were subsequently turned  off. Some researchers have observed that many bird and bat kills occur  during the time of year that has the lowest wind production. For example,  most bats are killed during the fall migration season on low wind nights.  Consequently, researchers suggested turning off some turbines during  these times in order to reduce kills. Perhaps most importantly, many  experts have noted that using preconstruction studies on wildlife and their  habitats can help identify locations for wind turbines that are less likely to  have adverse impacts.
section_title: Regulating Wind Power Facilities on Nonfederal Land Is Largely the Responsibility of State and Local Governments
paragraphs: Since most wind power development has occurred on nonfederal land,  regulating wind power facilities is largely a state and local government  responsibility. In the six states we reviewed, wind power development is  subject to local-level processes, state-level processes, or a combination of  the two. For example, in three of the six states, local governments regulate  the development of wind power and generally require wind developers to  adhere to local zoning ordinances and to obtain special use permits before  construction. The federal role in regulating wind power development is  limited to projects occurring on federal lands or those that have some form  of federal involvement, such as projects that receive federal funding; to  date, there have been relatively few wind power projects on federal land. In  these cases, wind power projects must comply with federal laws as well as  any relevant state and local laws.
subsections: section_title: State and/or Local Governments Regulate Wind Power on Nonfederal Lands
paragraphs: State and/or local governments regulate the development and operation of  wind power facilities on nonfederal lands. The primary permitting  jurisdiction for wind power facilities in many states is a local planning  commission, zoning board, city council, or county board of supervisors or  commissioners. Typically, these local jurisdictional entities regulate wind  projects under zoning ordinances and building codes. In some states, one  or more state agencies play a role in regulating wind power development,  such as natural resource and environmental protection agencies, state  historic preservation offices, industrial development and regulation  agencies, public utility commissions, or siting boards. In addition, some  states have environmental laws that impose requirements on many types of  construction and development, including wind power, that state and local  agencies must follow. The regulatory scheme for wind power in the six  states we reviewed included all of these scenarios (see table 1).
In the six states we reviewed, we found that approval for the construction  and operation of a wind power facility is typically provided in permits that  are often referred to as site, special use, or conditional use permits or  certificates. Such permits often include various requirements, such as  “setback” provisions—which stipulate how far wind power turbines must  be from other structures, such as roads and residences—and  decommissioning requirements that are intended to ensure that once a  wind power facility ceases operation, its structures are removed and the  landscape is restored according to a specific standard. State and local  regulations may require postconstruction monitoring studies to assess a  facility’s impact on the environment. In one state we reviewed, facilities are  required to submit periodic reports on issues related to its operation and  impact on the surrounding area.
In most of the six states we reviewed, state and local regulations related to  wind power are evolving as the industry has developed in the states  because government agencies realized that their existing authorities were  not applicable to wind power. For example, when wind power began to  emerge in Minnesota, an advisory task force held public meetings to  determine how to proceed in permitting development. In part based on  concerns raised from counties during these meetings, responsibility for  permitting larger facilities was given to the state. In addition, West Virginia  finalized new regulations for electric-generating facilities in May 2005 that  include provisions specific to wind power facilities. Prior to this, the state  made decisions on a case-by-case basis. Similarly, the Pennsylvania Game  Commission is developing a policy for wind power development on its  lands in response to private interest in promoting renewable energy  sources on state property. Officials with the state’s Department of  Environmental Protection also told us that they are examining a number of  options, including developing statewide rules and model ordinances that  could be adopted by local authorities.
Some state and local regulatory agencies we reviewed generally had little  experience or expertise in addressing environmental and wildlife impacts  from wind power. For example, officials in West Virginia told us that they  did not have the expertise to evaluate wildlife impacts and review studies  prior to construction, although such studies are required. Instead, they said  they rely on the public comment period while permits are pending for  concerns to be identified by others, such as FWS and the state Division of  Natural Resources. In addition, Alameda County officials in California told  us that they did not have the expertise to assess the impacts of wind facility  construction but rely on technical consultants during the permitting stage,  and that they are planning to form a technical advisory committee for  assistance with postapproval monitoring. In some of the states we  reviewed, state agencies were conducting outreach efforts with local  governments since wind power development is still a relatively new  industry for regulators. These efforts typically focus on educating local  regulators about the issues that are often encountered during wind power  development and about how permitting can be handled. These efforts may  also include providing sample zoning ordinances and permits.
subsections: section_title: California
paragraphs: California had the most installed wind power in the country, with 2,096 MW  of generating capacity as of April 2005 and an additional planned capacity  of 365 MW. California was the first state in which large wind farms were  developed, beginning in the early 1980s. It is also one of the few states with  significant wind power development on federal land, with over 250 MW on  land owned by the Bureau of Land Management (BLM). Aside from the  facilities on BLM land, the state relies on local governments to regulate  wind power. In addition to the local permitting process, the California  Environmental Quality Act requires all state and local government agencies  to assess the environmental impacts of proposed actions they undertake or  permit. This law requires agencies to identify significant environmental  effects of a proposed action and either avoid or mitigate significant  environmental effects, where feasible.
We met with officials from Alameda County and Contra Costa County,  which are home to the Altamont Pass Wind Resource Area—at one time the  largest wind energy facility in the world. In both counties, local land use  ordinances allow wind power development on agricultural lands. These  counties originally issued conditional or land use permits to various wind  power developers in the 1980s that contained approval conditions,  including requirements for setbacks from property lines and noise limits.  As previously discussed, the Altamont Pass Wind Resource Area was  subsequently found to be responsible for the deaths of numerous raptor  species. The counties are currently renewing or amending some of the  permits for facilities in this area and will add permit conditions in an  attempt to reduce avian mortality. Alameda County officials were working  with various federal and state agencies, environmental groups, and wind  energy companies to agree on specific permit conditions. At the time of this  report, Alameda County has recently approved a plan that is aimed at  reducing bird deaths at Altamont Pass by removing some existing turbines,  turning off selected turbines at certain times, implementing other habitat  modification and compensations measures, and gradually replacing  existing turbines with newer turbines. In addition, Contra Costa County  had completed the permitting for a wind power facility that included a  number of conditions to reduce avian mortality.
section_title: Minnesota
paragraphs: Minnesota had 615 MW of installed wind generating capacity as of April  2005 and an additional planned capacity of 213 MW. Wind power  development in Minnesota is subject to either local or state permitting  procedures, depending on the size of the project. Local governments  generally issue conditional use permits or building permits to wind power  developers for facilities under 5 MW. We spoke with officials in Pipestone  County, which was the first in the state to adopt a wind power ordinance.  This ordinance focuses mainly on setbacks and decommissioning  requirements. In southwestern Minnesota—which includes Pipestone  County and most of the wind power development in the state—a 14-county  renewable energy board is working to adopt a “model” wind power  permitting ordinance that would provide uniformity for regulating  development in the region. Two factors that officials cited in pursuing such  guidance is the recognition that development is likely to occur under the 5  MW threshold for state permitting, and that wind power developers would  benefit from uniform regulations.
Between 1995 and the first half of 2005, the Minnesota Environmental  Quality Board—comprised of 1 representative from the governor’s office, 5  citizens, and the heads of 10 state agencies—was responsible for regulating  large wind energy systems that are 5 MW or larger, studying environmental  issues, and ensuring state agency compliance with state environmental  policy. Effective July 1, 2005, authority for permitting these large wind  energy systems was transferred to the Minnesota Public Utilities  Commission. The commission requires, among other things, an analysis of  the proposed facility’s potential environmental and wildlife impacts,  proposed mitigative measures, and any adverse environmental effects that  cannot be avoided. Instead of requiring individual wind developers to  conduct their own assessments of impacts to wildlife, Minnesota took a  different approach. Since much of the wind power development is  concentrated in the southwestern part of the state, the state determined  that it would be more efficient to conduct one large-scale study, rather than  requiring each developer to conduct individual studies. Thus, the state  required wind developers to participate in a 4-year avian impact study at a  cost of about $800,000 as well as a subsequent 2-year bat study. The studies  concluded that the impacts to birds and bats from wind power are minimal.  Therefore, on the basis of the results of the state-required studies, state and  local agencies in Minnesota are not requiring postconstruction studies for  wind power development in this portion of the state. The costs for these  studies were charged back to individual wind developers on the basis of the  number of megawatts built or permitted within a specified time frame.
section_title: New York
paragraphs: New York had three operating wind power facilities, with 49 MW of  installed wind generating capacity as of April 2005. An additional 350 MW  of wind power capacity is planned for the state. According to state officials,  local governments permit the development of wind power in the state using  their zoning authorities. In addition to this local permitting, the state has an  environmental quality review act that requires all state and local  government agencies to assess the environmental impacts of proposed  actions, including issuing permits to wind power facilities. This law  requires that an environmental impact statement be conducted if a  proposed action is determined to have a potentially significant adverse  environmental impact. Because wind power is still new to the state and  there are a significant number of proposed facilities, a state agency focused  on promoting energy development is beginning a program for educating  local communities about regulating wind power. This program includes  examples of zoning ordinances that have been used in other counties.
We met with officials from the Town of Fenner—in north-central New  York—which has the largest wind power facility in the state. On the basis  of complaints about noise from the first facility permitted by the town, the  local planning board now requires that turbines be located a certain  distance from residences. In order to comply with the state’s environmental  law, the town conducted an environmental assessment to determine the  potential impacts of the proposed facility and determined that the project  would not have any significant adverse environmental impacts or pose a  significant risk to birds. However, elsewhere in New York, approval of one  wind power project is under review given concerns expressed by  environmental groups and the state environmental and conservation  agency about potential impacts to migratory birds.
section_title: Oregon
paragraphs: Oregon had five large wind projects, with a total of 263 MW of installed  wind power generating capacity as of April 2005 (see fig. 5).
Several new wind projects and expansions are under way or being planned  that would take total capacity in Oregon to more than 700 MW. Similar to  Minnesota, wind power regulation in Oregon is subject to either local or  state permitting procedures, depending on the size of the project. Local  governments issue conditional use permits for facilities capable of  generating up to 105 MW peak capacity. For example, in Sherman County,  the planning commission approved a 24 MW wind power project near  Klondike in north-central Oregon. Under its zoning authority, the county  attached various conditions to the project’s permit, including an avian  postconstruction study, and decommissioning and removal requirements. If  projects exceed 105 MW peak capacity, they are permitted by the Oregon  Energy Facility Siting Council, which makes decisions about issuing site  certificates for energy facilities. The siting council is a seven-member  citizen commission that is appointed by the governor. Wind power projects  that are subject to the council’s jurisdiction must comply with the council’s  standards and applicable statutes. Some of the standards are specific to  wind power, such as design and construction requirements to reduce visual  and environmental impacts. The council also ensures that wind power  facilities are constructed and operated in a manner consistent with state  rules, such as state fish and wildlife habitat mitigation goals and standards,  and local agency ordinances. In addition, regulations protect against  impacts on the surrounding community by requiring that minimal lighting  be used to reduce visual impacts, and protect some bird species by  requiring that developers avoid creating artificial habitat for raptors or  raptor prey. Also in Oregon, energy development—including wind  power—must not adversely impact scenic and aesthetic values and is  prohibited in certain areas, such as state parks.
section_title: Pennsylvania
paragraphs: Pennsylvania had 129 MW of installed wind generating capacity as of April  2005 and applications for an additional 145 MW to be developed (see fig. 6).
In Pennsylvania, wind power is regulated by local governments; no state  agency has the authority to specifically regulate wind power development.  For example, in Somerset County, which is home to the first wind power  facility in the state, the county’s planning commission regulates wind  power development through an ordinance that allows for subdividing  existing land. This ordinance contains requirements for setbacks and  decommissioning. Some county and state officials have suggested that the  state should provide a consistent framework for wind power development.  The state, through its Pennsylvania Wind Working Group, is currently  discussing whether there should be uniform state-level siting guidelines or  regulations for wind power development. Pennsylvania was the only state  of the six we reviewed that did not have state-level requirements for  environmental assessments. However, one state official told us that many  developers have done some environmental studies—generally including  wildlife, noise, and protection of scenic vistas (i.e., viewshed)—in an  attempt to head off criticism or opposition to a proposed project.
section_title: West Virginia
paragraphs: West Virginia had one operating wind power facility, with 66 MW of  installed wind power generating capacity and a planned additional capacity  of 300 MW for the state (see fig. 7). The state’s Public Service Commission  has been the only agency involved in regulating wind power to date,  although state officials noted that local governments could get involved  through their zoning authorities. Prior to 2005, West Virginia permitted  construction and operation of wind power facilities under laws and  regulations designed to regulate utilities providing electrical service  directly to its citizens. Wind power facilities are wholesale generators and  do not provide service to consumers, and according to commission  officials, several provisions of these regulations were not relevant to wind  power facilities. As a result, in 2003, the state amended the legislation to  specifically address the permitting of wholesale electric generators, such  as wind power.
West Virginia followed the regulations in place before the legislation was  amended to approve construction of the two wind power facilities in the  state; one of these facilities has yet to be constructed. During the public  comment periods for these facilities, concerns were raised regarding  potential impacts to wildlife. As a result, certain conditions were required  of the developers, such as prohibiting turbines in certain locations and  requiring postconstruction wildlife studies. In May 2005, the state  finalized new regulations for wholesale electric-generating facilities that  include provisions specific to wind power facilities. For permitting wind  power facilities, West Virginia regulations now require spring and fall avian  migration studies, avian and bat risk assessments, and avian and bat  lighting studies.
section_title: Federal Government’s Role in Regulating Wind Power Is Generally Limited to Facilities on Federal Land
paragraphs: The federal government’s role in regulating wind power development is  limited to projects occurring on federal lands or projects that have some  form of federal involvement. While the Federal Energy Regulatory  Commission regulates the interstate transmission of electricity, natural gas,  and oil, it does not approve the physical construction of electric generation,  transmission, or distribution facilities; such approval is left for state and  local governments. Certain standards issued by the Federal Aviation  Administration apply to wind power facilities and other tall structures, on  all lands. These standards are intended to protect aircraft and specify the  type of lighting that should be used for structures of a certain height.
Since the majority of wind development to date has been on nonfederal  land or has not required federal funding or permits, the federal government  has had a limited role in regulating wind power facilities. In those cases  where federal agencies do regulate wind power, projects must comply both  with state and local requirements and with any applicable federal law. At a  minimum, these laws will include the National Environmental Policy Act  and the Endangered Species Act. These laws often require  preconstruction studies or analyses of proposed projects, and possibly  project modifications to avoid adverse environmental effects. For example,  if the development of a proposed wind power project on federal land could  impact wildlife habitat and/or species protected under the Endangered  Species Act, permitting of the project would involve coordination and  consultation with FWS and/or the National Marine Fisheries Service to  determine the potential harm to species and the steps that may be  necessary to avoid or offset the harm.
To date, BLM has been the only federal agency with wind energy  production, with about 500 MW of installed wind power capacity. This  wind energy development is located in Southern California in the San  Gorgonio Pass and Tehachapi Pass areas, and in the Foote Creek Rim and  Simpson Ridge areas of Wyoming. According to BLM officials, as of June  2005, they had authorized 88 applications for wind energy development on  their land and had 68 pending applications—most of which are in California  and Nevada. Energy development on BLM-administered lands is regulated  through its process for granting private parties access to federal lands,  which is referred to as granting a “right-of-way authorization.” BLM’s  Interim Wind Energy Development Policy establishes the requirements for  granting these authorizations to wind energy facilities. This policy requires  that all proposed facilities conduct the necessary assessments and analyses  required by the National Environmental Policy Act, the Endangered  Species Act, and other appropriate laws. In one case, some changes have  been made to the location of some wind power turbines because of  potential impacts to avian species that were identified during these  preconstruction studies.
Because of an increased focus on developing energy sources on public  lands, BLM has proposed revising their interim policy by developing a wind  energy development program that would establish comprehensive policies  and best management practices for addressing wind energy development.  As a part of this effort, BLM issued a programmatic environmental impact  statement in June 2005 that assesses the social, environmental, and  economic impacts of wind power development on BLM land. This  document also identifies best management practices for ensuring that the  impacts of wind energy development on BLM lands are kept to a minimum.  While subsequent proposed wind power facilities will still need to conduct  some environmental assessments, they can rely on BLM’s programmatic  assessment for much of the needed analyses. BLM hopes that the  availability of this assessment will enable wind power development to  proceed more quickly on its lands, assuming that such development  complies with needed requirements.
section_title: Federal and State Laws Protect Wildlife
paragraphs: As with any other activity, federal and state laws afford protections to  wildlife from wind power. Three federal laws—the Migratory Bird Treaty  Act, the Bald and Golden Eagle Protection Act, and the Endangered  Species Act—generally forbid harm to various species of wildlife. While  each of the laws allows some exceptions to this, only the Endangered  Species Act includes provisions that would permit a wind power facility to  kill a protected species under certain circumstances. While wildlife  mortality events have occurred at wind power facilities, the federal  government has not prosecuted any cases against wind power companies  under these wildlife laws, preferring instead to encourage companies to  take mitigation steps to avoid future harm. Regarding state wildlife  protections, all of the six states we reviewed had statutes that can be used  to protect some wildlife from wind power impacts. However, similar to  FWS, no states have taken any prosecutorial actions against wind power  facilities where mortalities have occurred.
subsections: section_title: Various Wildlife Protections Are Provided by Three Federal Laws
paragraphs: The primary federal regulatory framework for protecting wildlife from  impacts from wind power includes three laws—the Migratory Bird Treaty  Act, the Bald and Golden Eagle Protection Act, and the Endangered  Species Act. (See table 2.)
FWS is primarily responsible for ensuring the implementation and  enforcement of these laws. In general, these laws prohibit various actions  that are deemed harmful to certain species. For example, each law  prohibits killing or “taking” a protected species, unless done under  circumstances that are expressly allowed by statute and authorized via  issuance of a federal permit. The Endangered Species Act may also prohibit  actions that harm a protected species’ habitat. In addition, each federal  agency that takes actions that have or are likely to have negative impacts  on migratory bird populations are directed by Executive Order 13186,  “Responsibilities of Federal Agencies to Protect Migratory Birds,” to work  with FWS to develop memorandums of understanding to conserve those  species. While the executive order was signed on January 10, 2001, no  memorandums have yet been signed. Wildlife species that fall outside the  scope of these three laws, such as many species of bats, are generally not  protected under federal law. However, FWS is not only responsible for  ensuring the survival of species protected by specific laws, but also for  conserving and protecting all wildlife.
All three of the federal wildlife protection laws prohibit most instances of  “take,” although each law provides for some exceptions, such as scientific  purposes. The Endangered Species Act is the least restrictive of these laws  in that it authorizes FWS to permit some activities that take a protected  species as long as the take meets several requirements, including a  requirement that the take be incidental to an otherwise legal activity. Wind  power facilities may seek an incidental take permit under this act for  facilities sited on private land or where no federal funding is used or federal  permit is required. The Migratory Bird Treaty Act and the Bald and Golden  Eagle Protection Act also allow permits for take, but incidental take of  migratory birds is not allowed. Under all three statutes, unauthorized  takings may be penalized, even if the offender had no intent to harm a  protected species.
Although not required by these federal laws, in some cases, state or local  entities that regulate wind power, or wind power developers themselves,  will consult with FWS for information on protected species or advice on  how to ensure that wind power facilities will not harm wildlife. For  example, in the Altamont Pass Wind Resource Area, Alameda County  officials and the companies operating wind facilities there have asked FWS  for technical assistance related to renewing permits for existing wind  power facilities. FWS officials told us that their technical assistance in  Altamont Pass is aimed at avoiding or minimizing potential impacts to  threatened or endangered species under the Endangered Species Act. In  addition, FWS officials from the New York field office told us that they are  asked to provide input on wind power proposals during the state’s  environmental review process. These officials noted that they will likely  not be able to review all of the wind power development proposals in the  state due to staffing constraints. Similarly, FWS officials in five of the six  states we reviewed told us that they have not conducted outreach to state  or local regulators to inform them of the potential for wildlife impacts from  wind power primarily because of workload constraints. If state and local  regulators do not consult with FWS during the regulatory process, it can be  difficult for FWS to encourage actions that might reduce wildlife deaths  before wind turbines are sited.
section_title: Federal Government Uses Prosecutorial Discretion in Dealing with Wildlife Mortality
paragraphs: Although FWS investigates all “take” of federal trust species, the  government has elected not to prosecute wind energy companies for  violations of wildlife laws at this time. In most of the states we reviewed,  there were relatively few law enforcement officials, and they told us that  they often had higher priority violations of federal wildlife laws than  mortality events due to wind power, particularly given the relatively low  levels of mortality that have occurred in most wind power locations. In  West Virginia, the agent-in-charge told us that most of his time is spent on  the commercialization of wildlife, such as the illegal import and export and  interstate commerce of protected species; illegal hunting is also a major  problem, particularly for bears and eagles. FWS law enforcement officials  in all of the six states we reviewed told us that in cases of violations, they  prefer to work cooperatively with the owners of wind power facilities to try  to get them to take voluntary actions to address impacts on wildlife, rather  than pursuing prosecution; however, other cases of wildlife violations, such  as illegal trade in protected species, are pursued via prosecution.
FWS has been investigating and monitoring avian mortality at Altamont  Pass for nearly 20 years, including the mortality of many protected species,  such as golden eagles and other raptors. Since that time, FWS has opened  investigations and tried to work with the owners of wind power facilities to  reduce the level of mortality. In the earlier years, some avian mortality was  due to electrocutions along power lines. FWS had been working with  electrical utility companies to resolve this problem elsewhere, and several  relatively easy “fixes” were known to reduce electrocutions. As a result of  official correspondence and conversations between FWS and company  officials, many companies implemented these fixes, and avian mortality  due to electrocutions has been reduced. However, large numbers of birds,  particularly raptors, were still being killed due to actual collisions with  wind turbines. On several occasions, FWS expressed concern about these  mortalities to wind power companies and Alameda County—the county  government with the most wind power development in California. In  response, Alameda County and some wind power companies have  conducted avian monitoring studies and tested several mitigation  measures, including painting turbine blades, installing perch guards on  lattice-work towers, and conducting rodent control. However, these  actions appear to have no significant impact on reducing avian mortality.  Since January 2004, the wind power companies have worked together to  develop an adaptive management plan for reducing avian mortality at  Altamont Pass. The plan contains various mitigation measures, such as  (1) removing old turbines and replacing them with fewer, new turbines and  (2) implementing a partial seasonal shutdown of turbines.
Over the past 6 years, FWS has referred about 50 instances of golden eagles  killed by 30 different companies in Altamont Pass either to the Interior  Solicitor’s office for civil prosecution or to the Department of Justice for  criminal prosecution. Officials noted that, in general, prosecutions by both  the Departments of the Interior and Justice focus on companies that kill  birds with disregard for their actions and the law, especially when  conservation measures are available but have not been implemented.  Despite the recurring nature of the avian mortality in Altamont Pass and  concerns from federal, state, and local officials, no prosecutions pursuant  to federal wildlife laws have been taken against any wind power  companies. Justice has not pursued prosecution in these cases, although  they currently have an open investigation on avian mortality in Altamont  Pass. As a matter of policy, Justice does not discuss the reasons behind  specific case declinations, nor does it typically confirm or deny the  existence of potential or actual investigations. However, Justice officials  told us that, in general, when deciding to prosecute a case criminally, they  consider a number of factors, including the history of civil or  administrative enforcement, the evidence of criminal intent, and what steps  have been taken to avoid future violations. Regarding the matters that FWS  referred for civil enforcement, Interior’s regional solicitor has also not  pursued prosecution in any of these cases. Interior’s Office of the Solicitor  San Francisco field office declined to pursue the most recent civil referrals  because Justice agreed to review turbine mortalities for possible criminal  prosecution. Some citizen groups remain concerned about the lack of  enforcement of federal and state wildlife protections. For example, in  November 2004, the Center for Biological Diversity filed a lawsuit against  the wind power companies in Altamont Pass to seek restitution for the  killing of raptors.
In addition to the avian mortalities at Altamont Pass, significant wildlife  mortality has also occurred at wind power locations in the Appalachian  Mountains in West Virginia and Pennsylvania in 2003 and 2004. FWS has  reviewed high numbers of bat kills; however, these bat species are not  protected under federal law. Several studies have been completed or are  under way in these regions to better determine the potential causes of the  mortality events and how future events might be mitigated. The FWS law  enforcement agent-in-charge in West Virginia told us that he has contacted  wind power developers of some of the proposed facilities in the state about  potential violations of federal wildlife laws should an endangered bat or  other protected species be killed. The agent said that he prefers to have  early involvement with wind power facilities, rather than wait for violations  to occur.
FWS law enforcement officials told us that the way they have handled avian  mortalities at wind power facilities is similar to how they deal with wildlife  mortality caused by other industries. These officials explained that FWS  recognizes that man-made structures will generally result in some level of  unavoidable incidental take of wildlife and, as a result, FWS reserves a level  of “enforcement discretion” in determining whether to pursue a violation of  federal wildlife law. Law enforcement officials told us that before FWS  pursues civil or criminal penalties, the agency prefers to work with a  company to encourage them to take mitigation and conservation steps to  avoid future harm. If a company shows a good-faith effort to reduce  impacts, FWS will likely not refer such a case for prosecution. If, however,  a company repeatedly refuses to take steps suggested by FWS, officials  said they are likely to refer it for prosecution.
Work that FWS has done with the electric power industry illustrates this  approach to resolving impacts to wildlife. FWS began working with the  electric power industry in the early 1980s to reduce significant avian  mortality due to collisions with and electrocutions at power lines,  particularly mortality events involving eagles and other large birds.  Pursuant to investigations of avian mortality at power lines and  conversations with individual companies, solutions were identified that  reduced mortality events. Because these solutions were relatively  inexpensive and generally easy to install based on scientific testing—and  were known to work—FWS law enforcement officials expected other  electric line companies to install them. According to law enforcement  officials, the threat of a potential conviction under the Migratory Bird  Treaty Act or the Bald and Golden Eagle Protection Act was generally  enough to get companies to voluntarily install the fixes without FWS  prosecuting them. However, by the late 1980s, some electric companies  were aware of mortalities due to electrocutions but were not taking actions  to resolve the causes. The federal government in 1998 charged an electric  utility cooperative—the Moon Lake Electric Association in Colorado and  Utah—with criminal violations of these two laws. This is the first and only  instance of a federal criminal prosecution of an electric power line  company under any of the three federal wildlife protection laws. Civil cases  have been filed and out-of-court agreements have been reached with other  electric utilities for similar cases of wildlife mortalities.
section_title: FWS Has Taken Some Proactive Steps to Help Minimize the Impacts of Wind Power on Wildlife
paragraphs: Even though FWS does generally not have a direct role in determining  whether and how wind power facilities are permitted, FWS has been  involved for about 20 years with the wind power industry to help avoid and  minimize impacts to wildlife from wind power development. FWS’s work  has been in the following three main areas—participating on a national  wind working group and in technical workshops, and issuing guidance.
subsections: section_title: Working Group
paragraphs: An FWS senior management official has been a member of the National  Wind Coordinating Committee since 1997. The wildlife workgroup serves  as an advisory group for national research on wind-avian issues and a  forum for defining, discussing, and addressing wind power-wildlife  interaction issues. The workgroup has facilitated five national avian-wind  power planning workshops to define needed research and explore current  issues. The most recent workshop also included discussions of bat-wind  turbine interactions. In addition, the working group released a report in  December 1999, Studying Wind Energy/Bird Interaction: A Guidance  Document, that includes metrics and methods for determining or  monitoring potential impacts on birds at existing and proposed wind  energy sites.
section_title: Workshops
paragraphs: FWS officials have participated in industry-sponsored workshops and  conferences. For example, a senior FWS official presented information on  cumulative impacts on wildlife from wind power at a 2004 workshop  cosponsored by the American Wind Energy Association and the American  Bird Conservancy. Another FWS official presented information on the  agency’s experience and expectations for regional wildlife issues at a  national workshop on wind power siting sponsored by the wind  association. FWS also helped to sponsor and organize, and participated in,  a 2004 bats and wind power technical workshop attended by both wind  industry representatives and researchers. As a result, FWS was  instrumental in establishing the Bats and Wind Energy Cooperative  discussed elsewhere in the report.
section_title: Guidance
paragraphs: In July 2003, in an effort to inform wind power developers about the  potential impacts to wildlife and encourage them to take mitigating actions  before construction, FWS issued interim voluntary guidelines for industry  to use in developing new projects. FWS developed the interim guidelines in  response to the Department of the Interior’s push to expand renewable  energy development on public lands. The wind power interim guidelines  are intended to assist FWS staff in providing technical assistance to the  wind energy industry to avoid or minimize impacts to wildlife and their  habitats through (1) proper evaluation of potential wind energy  development sites, (2) proper location and design of turbines, and (3) pre-  and postconstruction research and monitoring to identify and assess  impacts to wildlife. The voluntary guidelines were open for public  comment for a 2-year period that ended on July 10, 2005. At the time of this  report, FWS had received numerous comments from the wind industry on  the guidelines. In general, industry representatives thought that the  guidelines were overly restrictive—to a degree not supported by the  relative risk that wind power development poses to wildlife compared with  other sources of mortality. FWS also had received comments from other  groups—such as the Ripley Hawk Watch, the Clean Energy States Alliance,  the Humane Society of the United States, the Massachusetts and  Pennsylvania Audubon, the American Bird Conservancy, Defenders of  Wildlife, and Chautaqua County Environmental Management Council—that  were generally in support of the guidance or recommended that it be put  into regulation. BLM also provided comments and expressed some  concerns over the review process outlined in the guidelines. FWS will be  reviewing and incorporating the public, industry, and agency comments  received on the interim guidelines as appropriate in order to revise and  improve them, and will solicit additional public input before disseminating  a final version.
In addition, FWS recently began developing a template for a letter to be  sent to wind power project applicants to alert them to federal wildlife  protection laws, FWS’s interim guidance, and FWS’s role in protecting  wildlife. FWS officials told us that they hope the letter will assist  developers in making informed decisions regarding site selection, project  design, and compliance with applicable laws. The availability of a  ready-to-use template is important because most field officials told us that  working with the wind power industry is just one of many responsibilities  in FWS offices that often do not have enough staff, given their workloads.
Field officials also noted that if wind power developers, their consultants,  or state or local regulatory agencies do not contact them, they may not  know about wind power projects until there is a problem with an operating  facility.
section_title: All Six States We Reviewed Have Wildlife Protections
paragraphs: Although federal jurisdiction for migratory birds has not been delegated to  the states and primary responsibility for the protection of these birds  resides with Interior, all states we reviewed had additional wildlife  protections. Responsibility for protecting species and implementing  wildlife laws and regulations is typically found in a state’s natural resource  protection agency. In some states, however, responsibility is assigned  according to the type of species addressed. For example, in some states,  agriculture departments address plant issues, while in other states, fish and  boat commissions address fish, amphibian, and reptile issues; in these  cases, wildlife agencies typically address the remaining species.
In all six states, the most common laws related to wildlife protection—and  likely the most utilized wildlife laws—are those that govern hunting and  fishing. These laws and regulations may include limits on the type and  number of species that can be killed and the manner in which they can be  taken. In addition to identifying the species that can be hunted or fished,  the six states we reviewed identify as threatened or endangered specific  species that are at risk for extinction or extirpation in their state. These  states also identify “species of concern” or rare species. Such species are  identified as a way to provide an early warning signal for species that are  not yet endangered or threatened, but could become so in the future.
All of the six states we reviewed have laws that provide at least some  degree of protection for species that are at risk of extinction or extirpation  in their state. These protections generally go beyond what the federal  Endangered Species Act provides by protecting more species than are  protected under the federal law, although the protections may not be as  extensive. In the five states that have specific protections, protection is  provided through prohibitions on taking a protected species. In some  cases, these protections are only applicable under certain circumstances.  For example, in Oregon, protections apply only to state actions or on  state-owned or -managed lands. All of the state laws or regulations that  include take prohibitions, also include exceptions for when permits can be  issued in order to allow the take to occur. Such permits are issued  according to prescribed conditions or on a case-by-case basis. Two of the  six states also provide protections for habitat. In West Virginia, the primary  protection for wildlife, aside from hunting and fishing regulations, is a  prohibition on the commercial sale of wildlife and specific protection for  bald and golden eagles.
Most of the states’ wildlife protection laws for threatened and endangered  species include enforcement provisions. In some cases, these laws identify  violations as misdemeanor crimes. Similar to FWS law enforcement’s  approach to wind power, we found that state agencies had not taken any  prosecutorial actions in response to wildlife mortalities at wind power  facilities. Instead, many state officials told us that they prefer—like  FWS—to work with developers to try to identify solutions to the causes of  mortality. For example, in Minnesota, after impacts to native prairie grass  caused by a wind power facility were discovered, the state natural resource  agency required the facility to purchase additional habitat elsewhere to  compensate for the loss. In California, Alameda County has worked with  wind power facilities and others, and recently approved a plan that is  aimed at reducing bird deaths at Altamont Pass by having wind power  companies turn off selected turbines at certain times and replace some  turbines with newer turbines.
State natural heritage programs serve as key sources of information on  wildlife for federal and state wildlife protection agencies. All six of the  states we reviewed have natural heritage programs that manage  information on natural resources, including threatened and endangered  species (all 50 states have such programs). These programs are part of an  international effort to gather and share information on biological  resources. This effort has slightly different designations and criteria for  identifying imperiled species and habitat than the federal Endangered  Species Act. In five of the states we reviewed, the natural heritage program  is run by the states’ natural resource agencies; in the sixth state, Oregon, it  is run by a university. Although West Virginia does not have a state  endangered species law and protects only bald and golden eagles, it does  identify other imperiled species through its natural heritage program.
State natural resource agencies—which typically house the natural  heritage programs—are sometimes consulted by a state or local wind  power regulator or a wind power developer during the permitting process  for help in identifying potentially sensitive species or concerns about  possible impacts to wildlife in general. For example, staff from West  Virginia’s natural resources agency were involved in reviewing wildlife  monitoring studies conducted by the first wind power facility in the state.  During the consultation process on another proposed facility in the state,  agency staff requested that certain studies be conducted because of  concerns about impacts on bat populations. Similarly, in Minnesota, natural  resource agency staff requested changes in the location, construction, and  operation of certain proposed wind power turbines through the state’s  environmental review process. However, in some cases, the process for  regulators or wind power developers to consult with natural resource  agency staff on wildlife is often an informal one and is not necessarily  required by states’ species protections or laws and regulations used to  permit wind power.
section_title: Conclusions
paragraphs: In the context of other sources of avian mortalities, it does not appear that  wind power is responsible for a significant number of bird deaths. While we  do not know a lot about the relative impacts of bat mortality from wind  power relative to other sources, significant bat mortality from wind power  has occurred in Appalachia. However, much work remains before scientists  have a clear understanding of the true impacts to wildlife from wind power.  Scientists, in particular, are concerned about the potential cumulative  impacts of wind power on species populations if the industry expands as  expected. Such concerns may be well-founded because significant  development is proposed in areas that contain large numbers of species or  are believed to be migratory flyways. Concerns are compounded by the fact  that the regulation of wind power varies from location-to-location and  some state and local regulatory agencies we reviewed generally had little  experience or expertise in addressing the environmental and wildlife  impacts from wind power. In addition, given the relatively narrow  regulatory scope of state and local agencies, it appears that when new wind  power facilities are permitted, no one is considering the impacts of wind  power on a regional or “ecosystem” scale—a scale that often spans  governmental jurisdictions. FWS, in its responsibility for protecting  wildlife, is the appropriate agency for such a task and in fact does monitor  the status of species populations, to the extent possible. However, because  wildlife, federally protected birds in particular, face a multitude of threats,  many of which are better understood than wind power, FWS officials told  us that they generally spend a very small portion of their time assessing the  impacts from wind power. Nonetheless, FWS has taken some steps to reach  out to the wind power industry by, among other things, issuing voluntary  guidelines to encourage conservation and mitigation actions at new wind  power facilities. In addition, FWS and the U.S. Geological Survey are  initiating some studies to capture data on migratory flyways to help  determine where the most potential harm from wind power might occur  and to gather data for use in assessing wind power’s cumulative impacts on  species. Although these are valuable steps in educating industry and  improving science, FWS has conducted only limited outreach to state and  local regulators about minimizing impacts from wind power on wildlife and  informing them about species that may be particularly vulnerable to  impacts from wind power. Such outreach is important because these are  the entities closest to the day-to-day decisions regarding where wind power  will be allowed on nonfederal land.
section_title: Recommendations for Executive Action
paragraphs: Given the potential for future cumulative impacts to wildlife species due to  wind power and the limited expertise or experience that local and state  regulators may have in this area, we recommend that the Secretary of the  Interior direct the Director of the FWS to develop consistent  communication for state and local wind power regulators. This  communication should alert regulators to (1) the potential wildlife impacts  that can result from wind power development; (2) the various resources  that are available to help them make decisions about permitting such  facilities, including FWS state offices, states’ natural resource agencies,  and FWS’s voluntary interim guidelines—and any subsequent  revisions—on avoiding and minimizing wildlife impacts from wind  turbines; and (3) any additional information that FWS deems appropriate.
section_title: Agency Comments and Our Evaluation
paragraphs: We provided copies of our draft report to the Department of the Interior  and received written comments. (See app. III for the full text of the  comments received and our responses.) Interior officials stated that they  generally agree with our findings and our recommendation in the report.  We also sent portions of the report to state and local regulators and state  wildlife protection agencies. Many of these entities provided technical  comments, which we incorporated as appropriate. Interior also provided  technical comments, which we incorporated where appropriate.
Interior officials agreed in most part with our recommendation to develop  consistent communication to deliver to state and local wind power  regulators. However, they stated that because the comment period on the  FWS voluntary interim guidelines has closed and final guidelines have yet  to be developed, it would be inappropriate to include these in such  communication. However, because FWS is currently disseminating the  voluntary interim guidelines on wind power to its field offices to share with  regulators and developers, we believe that it is appropriate to include  reference to this document in communications to local and state  regulators. As Interior noted, these voluntary guidelines are currently  undergoing review and revision. Therefore, it would be appropriate to draw  attention to this fact in any such communication and to provide  information about how the most current version might be accessed.
As agreed with your offices, unless you publicly announce the contents of  this report earlier, we plan no further distribution until 30 days from the  report date. At that time, we will send copies of this report to the Secretary  of the Interior, as well as to appropriate congressional committees and  other interested Members of Congress. We also will make copies available  to others upon request. In addition, the report will be available at no charge  on the GAO Web site at http://www.gao.gov.
If you or your staffs have questions about this report, please contact me at  (202) 512-3841. Contact points for our Offices of Congressional Relations  and Public Affairs may be found on the last page of this report. Key  contributors to this report are listed in appendix IV.
section_title: Objectives, Scope, and Methodology
paragraphs: On the basis of a June 22, 2004, request from the Ranking Democratic  Members—House Resources Committee and the House Appropriations  Subcommittee on Science, the Departments of State, Justice, and  Commerce and Related Agencies—and of subsequent discussions with  their staffs, we reviewed wind energy development and impacts on wildlife.  Specifically, we assessed (1) what available studies and experts have  reported about the impacts of wind power facilities on wildlife in the  United States and what can be done to mitigate or prevent such impacts,  (2) the roles and responsibilities of government agencies in regulating wind  power facilities, and (3) the roles and responsibilities of government  agencies in protecting wildlife from the risks posed by wind power  facilities.
To determine what available studies and experts have reported about the  direct impacts of wind power facilities on wildlife, we reviewed scientific  studies and reports on the subject that were conducted by government  agencies, industry, and academics. Our review focused on wildlife mortality  as opposed to indirect impacts, which include habitat modification and  disruption of feeding or breeding behaviors due to wind power facilities.  We used several criteria to select studies for review. We chose studies that  included original data analyses (rather than summaries of existing  literature) conducted in the United States since 1990, and we primarily  focused on the impact of wind power on birds and bats and/or ways in  which to mitigate those impacts. We did not include preconstruction  assessments of wildlife impacts in our review. We excluded studies that had  preliminary findings when there was a more recent version available. We  located studies using a database search with keywords of “wind power”  and “birds,” “bats,” or “wildlife” in the following databases: AGRICOLA,  DOE Information Bridge, National Environmental Publications  Information, Energy Citations Database, Energy Research Abstracts,  Environmental Sciences and Pollution Management, and JSTOR. In  addition, we located studies using bibliographies of other studies and  through publicly available lists of studies from the National Wind  Coordinating Committee, the California Energy Commission, the National  Renewable Energy Laboratory, and Bat Conservation International. We  shared our list of studies with experts and asked them to identify any  studies missing from our list. When studies were not publicly available, we  contacted the authors and attempted to obtain copies. Using these methods  and criteria, we obtained 31 studies. We reviewed the studies’ methodology,  assumptions, limitations, and conclusions for the purposes of excluding studies that did not ensure a minimal level of methodological rigor. We  excluded 1 study, leaving 30 studies that are used in this work. In addition  to these studies, we also reviewed two summaries of studies produced by  the National Wind Coordinating Committee. Generally, we did not directly  use these two summary studies, we did use them as a check for our  conclusions and findings in relation to the studies we reviewed. We also  interviewed experts and study authors from the Department of the  Interior’s U.S. Fish and Wildlife Service (FWS), state government agencies,  academia, wind industry, and conservation groups and obtained their views  on the risks of wind power facilities to migratory birds and other wildlife  and on ways in which to minimize these risks.
To determine the roles and responsibilities of government agencies in  regulating wind power facilities, we identified and evaluated relevant  federal laws and regulations for wind power development. We reviewed a  nonprobability sample of six states with wind power development— California, Minnesota, New York, Oregon, Pennsylvania, and West Virginia.  We selected these states to reflect a range in installed capacity, different  regulatory processes, a history of wind power development, and  geographic distribution and to reflect our requesters’ interests. For these  states, we identified and evaluated relevant state and local laws and  regulations for wind power development. We interviewed federal officials  from FWS, Bureau of Land Management, and Interior’s Office of the  Solicitor as well as officials from the Department of Justice. We  interviewed officials from FWS headquarters and from field office locations  in the six states that we selected. We also interviewed officials from various  state agencies, such as the Oregon State Siting Council and the West  Virginia Public Service Commission, and from local and county  governments that were responsible for issuing permits or certificates for  the development of wind power facilities in their states. Finally, we visited  wind power facilities in California, New York, Oregon, Pennsylvania, and  West Virginia and interviewed wind industry company officials.
To determine the roles and responsibilities of government agencies in  protecting wildlife from the risks posed by wind power facilities, we  identified and evaluated relevant federal, environmental, and wildlife  protection laws and regulations. We interviewed FWS law enforcement  officials from headquarters and the six states that we reviewed. For the six  states that we selected, we identified and evaluated relevant state and local  environmental and wildlife protection laws. We also interviewed officials  from state environmental and wildlife agencies in California, Minnesota,  New York, Oregon, Pennsylvania, and West Virginia.
We conducted our work between December 2004 and July 2005 in  accordance with generally accepted government auditing standards,  including an assessment of data reliability and internal controls.
section_title: Studies of Bird, Bat, and Raptor Fatality Rates, by Region
paragraphs: Table 3 includes only studies where calculating bird or bat mortality was a  primary goal. Some studies may contain more than one study location.
section_title: Comments from the Department of the Interior
paragraphs: The following are GAO’s comments on the Department of the Interior’s  letter dated September 2, 2005.
subsections: section_title: GAO Comments
paragraphs: The Department of the Interior raised one issue with our recommendation  that we have addressed in the Agency Comment and Our Evaluation  section in the report. We address below the four other points the  department raised in its letter. In addition, the department provided  technical comments that we have incorporated into the report, as  appropriate. 1. We agree that it is important to point out that many of these studies  were not scientifically peer-reviewed and have added a footnote to this  effect in the body of the report. However, we disagree that in some  cases protocols used in the studies were unknown. As we explain in  appendix I, we only included studies that were determined to have  reasonably sound methodologies. We did not include any study for  which we were unable to assess the protocols or methodology.  2. We believe the section on law enforcement reflects continued  investigation of “take” of federal trust species by wind turbines and  FWS’s and the Department of Justice’s enforcement and prosecutorial  discretion, although we have added some clarification on these points. 3. We did not find any instances where state or local agencies that  regulate wind power included in our review had incorporated or  adopted the interim guidelines into their own jurisdictional  requirements for approving wind power facilities. We did, however, find  agencies in two states that had used the guidelines to inform either  their development of regulations or their monitoring of the wildlife  impacts at operating wind power facilities. 4. We did not assess how various local controls provide for protection of  individual animals that are interjurisdictional in their life cycles. The  section of the report that pertains to state wildlife laws is descriptive in  nature and serves to highlight the fact that state laws sometimes  provide additional protections to species, beyond federal laws, that  may be affected by wind power. We added language to highlight that  federal jurisdiction for migratory birds has not been delegated to the  states, and that primary responsibility for the protection of these birds  resides with the federal government (Interior).
section_title: GAO Contact and Staff Acknowledgments
subsections: section_title: GAO Contact
section_title: Staff Acknowledgments
paragraphs: In addition to the individual named above, Patricia McClure, Assistant  Director; José Alfredo Gómez; Kimberly Siegal; and William Roach made  key contributions to this report. Important contributions were also made  by Judy Pagano, John Delicath, and Omari Norman.
section_title: Bibliography
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