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Golden eagle nesting territory distribution in wind energy landscapes of the southern Great Plains

D.W. Stahlecker·Z.P. Wallace·D.G. Mikesic·Clint W. Boal·R.K. Murphy·W.H. Howe·M.B. Ruehmann
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Abstract

Deaths of four Golden Eagles ( Aquila chrysaetos ) due to collision trauma at a new wind energy facility in east-central New Mexico during 2004–2005 prompted concerns about the species' population status in the encompassing Southern Great Plains region, primarily because its breeding distribution there was poorly documented and wind energy development was expanding rapidly. Therefore, we conducted aerial searches for Golden Eagle nests across northeastern New Mexico, northwestern Texas, western Oklahoma, and adjacent portions of Colorado and Kansas during 2006–2009 and 2015–2020. We delineated five Golden Eagle Nest Search Areas (NSAs) with unique physiographic/geological origins. Individual NSAs were searched partially or entirely for up to 8 yr. Collectively, we identified 123 nesting territories (NTs) occupied by Golden Eagles ≥ 1 yr, of which 94 (76%) were in northeastern New Mexico. The most NTs (40) were in the 11,720-km 2 Highlands NSA. Greatest NT density (126.6 km 2 /NT) and shortest NT nearest neighbor distance (7.4 km) were in the 3533-km 2 Northern Caprock NSA. Wind turbines existed near (within 3.2 km) eight nests distributed among five of 28 NTs in the Northern Caprock and were planned for sites in two occupied NTs. Elsewhere, only potential turbines were near nests and only within six NTs. The number of nesting territories we found underscores the importance of the Southern Great Plains to Golden Eagles, even though this region lies at the eastern margin of the species' western North American breeding range. Our data provide strong support for protecting breeding habitat from potential threats, particularly those posed by wind energy development, and are also a foundation for long-term population monitoring.

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Journal of Raptor ResearchArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 34° to 38.1° latitude; -106° to -100° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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D.W. Stahlecker, Z.P. Wallace, D.G. Mikesic, Clint W. Boal, R.K. Murphy, W.H. Howe, M.B. Ruehmann. 2022. Golden eagle nesting territory distribution in wind energy landscapes of the southern Great Plains. https://doi.org/10.3356/jrr-21-68

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