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Resource Documents: Wildlife (212 items)


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Documents presented here are not the product of nor are they necessarily endorsed by National Wind Watch. These resource documents are provided to assist anyone wishing to research the issue of industrial wind power and the impacts of its development. The information should be evaluated by each reader to come to their own conclusions about the many areas of debate.

Date added:  December 21, 2016
Europe, WildlifePrint storyE-mail story

Patterns of migrating soaring migrants indicate attraction to marine wind farms

Author:  Skov, Henrik; et al.

Monitoring of bird migration at marine wind farms has a short history, and unsurprisingly most studies have focused on the potential for collisions. Risk for population impacts may exist to soaring migrants such as raptors with K-strategic life-history characteristics. Soaring migrants display strong dependence on thermals and updrafts and an affinity to land areas and islands during their migration, a behaviour that creates corridors where raptors move across narrow straits and sounds and are attracted to islands. Several migration corridors for soaring birds overlap with the development regions for marine wind farms in NW Europe. However, no empirical data have yet been available on avoidance or attraction rates and behavioural reactions of soaring migrants to marine wind farms. Based on a post-construction monitoring study, we show that all raptor species displayed a significant attraction behaviour towards a wind farm. The modified migratory behaviour was also significantly different from the behaviour at nearby reference sites. The attraction was inversely related to distance to the wind farm and was primarily recorded during periods of adverse wind conditions. The attraction behaviour suggests that migrating raptor species are far more at risk of colliding with wind turbines at sea than hitherto assessed.

Henrik Skov, Mark Desholm, Stefan Heinänen, Johnny A. Kahlert, Bjarke Laubek, Niels Einar Jensen, Ramūnas Žydelis, Bo Præstegaard Jensen

Published 21 December 2016.
Biology Letters, volume 12, issue 12
DOI: 10.1098/rsbl.2016.0804

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Date added:  November 8, 2016
Environment, Regulations, WildlifePrint storyE-mail story

Ecological impact assessments fail to reduce risk of bat casualties at wind farms

Author:  Lintott, Paul; Richardson, Suzanne; Hosken, David; Fensome, Sophie; and Mathews, Fiona

Demand for renewable energy is rising exponentially. While this has benefits in reducing greenhouse gas emissions, there may be costs to biodiversity [1]. Environmental Impact Assessments (EIAs) are the main tool used across the world to predict the overall positive and negative effects of renewable energy developments before planning consent is given, and the Ecological Impact Assessments (EcIAs) within them assess their species-specific effects. Given that EIAs are undertaken globally, are extremely expensive, and are enshrined in legislation, their place in evidence-based decision making deserves evaluation. Here we assess how well EIAs of wind-farm developments protect bats. We found they do not predict the risks to bats accurately, and even in those cases where high risk was correctly identified, the mitigation deployed did not avert the risk. Given that the primary purpose of an EIA is to make planning decisions evidence-based, our results indicate that EIA mitigation strategies used to date have been ineffective in protecting bats. In the future, greater emphasis should be placed on assessing the actual impacts post-construction and on developing effective mitigation strategies.

The high legal protection of bats (e.g., Europe: EUROBATS 2014; North America: Endangered Species Act 1973), together with the known risks to bats from wind farms (e.g. [2]), means that detailed preconstruction ecological assessments are frequently undertaken. Acoustic surveys are widely used to provide an estimate of bat activity from which collision risk is inferred. However, bat activity is highly variable – both spatially and temporally. It is therefore unclear whether the survey protocols currently employed assess bat activity with sufficient precision and repeatability to be of practical value in inferring risk for developments. Determining the best methods to assess likely impacts on bats from wind turbines is regarded as a research priority by EUROBATS [3]. To our knowledge, there has only been one study (in North America) that investigates the value of using bat activity to predict the risk to bats from future wind turbines. This found that pre-construction bat activity was not a significant indicator of collision risk [4]; however, the value of EIAs in predicting risk was not assessed. We therefore assessed the effectiveness of pre-construction EIAs as a tool to aid decision-makers in determining the impact of wind energy on bats.

We surveyed 46 wind farms across the UK for bat fatalities as part of a separate field study investigating the impact of wind turbines on bats. We were able to obtain EcIAs for 29 of these sites; the remaining EcIAs could not be obtained from public sources or developers. Eighteen EcIAs concluded that a field assessment of bat presence/activity was not required (evidenced by statements in the EcIA such as “Surveys are unnecessary as the development does not affect any features likely to be used by bats”), or inferred based on field surveys that no significant effects on any protected species would occur (see also Table S1 in Supplemental Information, published with this article online). However, during our post-construction surveys we found that half of these sites contained casualties (ranging from one to 64 fatalities per month during the July–October survey period), and 97% had evidence of bat activity (ranging from one to 236 passes per night). The perception of risk to bats during EcIAs was not significant in predicting either bat casualty rates (Figure 1A) or activity levels post-construction (see also Figure S1). While there was a positive relationship between sites ranked by perceived risk to bat populations and the ranking of sites by casualties per month (Figure 1B), there was considerable scatter in the data, and 9 sites identified as having the lowest risk had more than 1 casualty per month.

Figure 1. The relationship between pre-construction assessment of risks to bats and post-construction fatalities. (A) The difference in the average number of bat casualties per site between wind farms where preconstruction surveys perceived different levels of risk. Error bars depict the standard error of the mean (n = 29). (B) The marginally significant relationship between ranked pre-construction assessment of risk to bats and ranked post-construction fatality estimates (ρ (29) = 0.36, p = 0.05). Sites are ranked in ascending order of perceived risk. Circle size is proportional to the number of sites at a particular ranking (range 1 to 3 sites).

Figure 1. The relationship between pre-construction assessment of risks to bats and post-construction fatalities. (A) The difference in the average number of bat casualties per site between wind farms where preconstruction surveys perceived different levels of risk. Error bars depict the standard error of the mean (n = 29). (B) The marginally significant relationship between ranked pre-construction assessment of risk to bats and ranked post-construction fatality estimates (ρ (29) = 0.36, p = 0.05). Sites are ranked in ascending order of perceived risk. Circle size is proportional to the number of sites at a particular ranking (range 1 to 3 sites).

Our results show that sites which may have been perceived as of poor quality for bats can contain casualties after wind turbine construction. Similarly, bat activity recording during pre-construction surveys may not accurately reflect activity levels post-construction. This may be due to bats changing their behaviour at turbines [5], as bats may be attracted to wind farm sites for a variety of reasons, including the emission of ultrasound from turbines [6] and increased prey availability [5]. It is therefore essential that future mitigation strategies are formed with an understanding of how bat behaviour differs at sites after turbines have been constructed. Additionally, surveying effort has to be adequate both spatially and temporally to assess risks to bats in the first place. Pre-construction surveys are conducted predominantly at ground level due to the difficulties and cost of surveying at height; however, where meteorological masts are in place (or as drone technology develops) then conducting acoustic surveys within the rotor-swept area may give a more accurate assessment of risk. But this relationship has yet to be tested.

Of those sites identified as posing a significant risk to bats in the EcIA surveys, risk does not appear to have been adequately mitigated. Indeed, one of these mitigated sites had the highest recorded casualty rate. In the UK, regulations state that “if significant harm cannot be avoided, adequately mitigated, or as a last resort, compensated for, planning permission should be refused” and similar legislation applies in many other countries. We conclude that significant harm was not avoided at these significant risk sites.

Given the economic cost of EcIAs, the value attached to their findings during planning applications, and the possible consequences to biodiversity of errors, it is vital that they are fit for the purpose. We highlight that although EIAs give the perception of rigorous safeguarding of environmental standards and may portray energy companies with an environmentally friendly public image, considerable time and expense goes into deploying bat detectors at pre-construction sites with little justification. Although the use of EIAs has evolved differently between nations [7], there is a pressing global need to identify the procedures which can accurately identify risk to bats (e.g., Brazil [8]). The precautionary principle indicates that sites perceived to contain little collision threat to bats should be treated with caution until there is a greater understanding of how to identify risk factors to bats. On occasions when mitigation is currently deemed unnecessary, post-construction surveys should still be conducted (e.g. carcass searches) to ensure that the predictions are accurate and bat behaviour has not altered from pre-construction levels. Establishing the species assemblage at a site may nevertheless have some value in identifying the presence of species at high collision risk and/or of particular conservation concern in the region. In mainland Europe, automated systems using weather variables and site-specific post-construction bat activity data have been used to trigger turbine curtailments to minimise bat collisions [9]. Pre-construction surveys may therefore still be useful as the data (e.g., nightly and seasonal peaks of activity) may provide an indication of the extent of curtailment that is required and therefore the economic viability of the project. Our results highlight the importance of longitudinal monitoring of major developments and a feedback mechanism for practitioners to share the success or failure of mitigation strategies.

Paul R. Lintott, Suzanne M. Richardson, David J. Hosken, Sophie A. Fensome, and Fiona Mathews
Hatherly Laboratories, Biosciences, College of Life and Environmental Sciences, University
of Exeter, Prince of Wales Road, Exeter, UK; and (S.A.F.) Centre for Ecology and Conservation, University of Exeter, Cornwall, Tremough, Penryn, Cornwall, UK.

Current Biology 26, R1119–36, November 7, 2016 [Correspondence]
doi: 10.1016/j.cub.2016.10.003


1. Wang, S., and Wang, S. (2015). Impacts of wind energy on environment: a review. Renew. Sustainable Energy Rev. 49, 437–443.

2. Arnett, E.B., and Baerwald, E.F. (2013). Impacts of wind energy development on bats: implications for conservation. In Bat Evolution, Ecology, and Conservation, R.A. Adams and S.C. Pedersen, eds. (Springer: New York), pp. 435–456.

3. Rodrigues, L., Bach, M.-J., Dubourg-Savage, B., Karapandža, D., Kovacˇ , T., Kervyn, J., Dekker, A., Kepel, P., Bach, J., Collins, C. et al. (2015). Guidelines for consideration of bats in wind farm projects – Revision 2014. EUROBATS Publication Series NO. 6 (English version). (Bonn: UNEP/EUROBATS Secretariat).

4. Hein, C.D., Gruver, J., and Arnett, E.B. (2013). Relating pre-construction bat activity and postconstruction bat fatality to predict risk at wind energy facilities: a synthesis. A report submitted to the National Renewable Energy Laboratory. Bat Conservation International, Austin, TX, USA.

5. Cryan, P.M., Gorresen, P.M., Hein, C.D., Schirmacher, M.R., Diehl, R.H., Huso, M.M., Hayman, D.T.S., Fricker, P.D., Bonaccorso, F.J., Johnson, D.H., et al. (2014). Behaviour of bats at wind turbines. Proc. Natl. Acad. Sci. USA 111, 15126–15131.

6. Kunz, T.H., Arnett, E.B., Erickson, W.P., Hoar, A.R., Johnson, G.D., Larkin, R.P., Strickland, M.D., Thresher, R.W., and Tuttle, M.D. (2007). Ecological impacts of wind energy development on bats: questions, research needs, and hypotheses. Front. Ecol. Environ. 5, 315–324.

7. Glasson, J., Therivel, R. and Chadwick, A. (2013). Introduction of Environmental Impact Assessment: Fourth Edition. (Routledge: New York).

8. Valença, R.B., and Bernard, E., (2015). Another blown in the wind: bats and the licensing of wind farms in Brazil. Natureza & Conservação 13, 117–122.

9. Behr, O., Brinkmann, R., Niermann, I., and Korner-Nievergelt. F. (2011). Fledermausfreundliche Betreibsalgorithm fur Windenergieanlagen. In Entwicklung von Methoden zur Untersuchung und Reduktion des Kollsionsrisikos van Fledermäusen an Onshore- Windenergieanlagen. Umwelt und Raum, eds R. Brinkmann., O. Behr., I. Niermann and M. Reich, eds. (Cuvillier Verlag: Göttingen), pp. 354–383.

Download original document: “Ecological impact assessments fail to reduce risk of bat casualties at wind farms”

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Date added:  October 27, 2016
Environment, U.S., WildlifePrint storyE-mail story

This Land Was Your Land: A Closer Look at 80 by 50

Author:  Bryce, Robert

Politicians from federal to local levels have joined in a pledge known as 80 by 50, an effort to cut carbon-dioxide emissions 80% by 2050. The pledges are long on fanfare but short on details. There is, however, a published literature that determines how to achieve so-called deep carbonization, and it involves a massive increase of renewable-energy sources, primarily wind and solar.

This report analyzes the extraordinary amount of land that would be needed to achieve 80 by 50 through wind and solar, the amount of additional high-voltage transmission capacity, and the growing resistance to local wind-energy projects. It also looks at what all this means for the populations of birds and bats, including endangered species.

Key Findings

Download original document: “This Land Was Your Land: A Closer Look at 80 by 50”

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Date added:  October 1, 2016
Environment, Law, Washington, WildlifePrint storyE-mail story

Reply Brief of Petitioners Friends of the Columbia Gorge and Save Our Scenic Area v. Bonneville Power Administration

Author:  Friends of the Columbia Gorge

To try to justify its violations of NEPA (including a failure to consider any alternatives besides the Applicant’s proposal and a failure to take a hard look at the Project’s environmental impacts), BPA leans upon the slender reed of lacking direct siting authority over the Project’s wind turbines. But the inescapable reality is that BPA evaluated the proposed wind turbines and the requested interconnection to its power grid together as components of the single action alternative in the FEIS. Moreover, BPA has conceded that if it were to deny the interconnection the turbines would not be built. Accordingly, BPA was required to comply fully with NEPA to inform its decision whether to approve or deny the interconnection.

Ultimately, BPA has authority to say “no”—to the interconnection, and thereby to the entire Project—and NEPA requires it to make an informed decision and thus potentially avoid or minimize harm to the environment. BPA’s litigation position posits an alternative reality in which the agency did not evaluate the wind turbines and interconnection together as a single action, and did not admit that the interconnection is a necessary element of the Project without which the wind turbines cannot be built. The analyses adopted in the FEIS—not the agency’s current litigation position—must be the focus of this Court’s review.

BPA’s arguments rely almost entirely on cases in which federal actions were completely distinct from non-federal actions—rather than intertwined, as the proposed wind turbines and interconnection are here—and on knocking down straw-man arguments that Friends does not make. The fact that BPA can cite no case where a court upheld an EIS that considered only a single action alternative involving several undefined variables underscores the unprecedented way BPA evaded NEPA’s express requirements.

Although BPA may “believe[] that the Project will be implemented in an environmentally responsible manner,” it failed to follow the procedures NEPA requires to draw an informed conclusion about likely harm from the proposed Project as compared to reasonable alternatives. BPA asks this Court to condone a NEPA analysis that in essence evaluated only a single, worst-case alternative and that lacked any evaluation whether the proposed mitigation measures could effectively reduce or eliminate harm.

Where an agency could prevent environmental harm, as BPA could do here by denying the requested interconnection, NEPA and this Court’s precedents require the agency’s decision to be fully informed and to include a complete understanding of the effects of reasonable alternatives—even alternatives not within BPA’s jurisdiction. An evaluation showing that changes to the number, locations, capacities, heights, or other details of the proposed wind turbines would cause significantly less harm to birds, bats, or scenic values might have led BPA to deny the requested interconnection. BPA’s uninformed decision violates NEPA and its procedures for ensuring informed, democratic decisionmaking.

Sept. 26, 2016, Docket No. 15-72788, United States Court of Appeals for the Ninth Circuit

Download original document: “Reply Brief of Petitioners Friends of the Columbia Gorge and Save Our Scenic Area v. Bonneville Power Administration”

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