Guiding conservation of golden eagle populations in light of expanding renewable energy development: a demographic and habitat-based approach

• Main Author: Tack, Jason Duane
• Other Authors: Noon, Barry, Fedy, Brad, Bailey, Larissa, Boone, Randall, Bowen, Zachary
• Format: Text
• Language: English
• Published: Colorado State University. Libraries 2016
• Subjects: demography; golden eagle; wind energy; Aquila chrysaetos
• Online Access: http://hdl.handle.net/10217/170394

Includes bibliographical references. 2015 Fall. Golden eagles (Aquila chrysaetoes) are an iconic wide-ranging predator distributed across the Northern Hemisphere. In western North America, populations are considered to be stable, though there is a mounting concern that an anticipated increase in renewable wind energy development will threaten populations. Wind turbines are a known source of mortality for many avian species including golden eagles, thus there is a pressing need to offer land managers conservation planning guidance in light of future development. Working with several collaborators, I aimed to develop applied research in support of golden eagle conservation, while thoroughly testing the analytical rigor of methods we employed to address such questions. In chapter 1, I developed a stochastic population model for golden eagles with coauthors Zack Bowen, Brad Fedy, and Barry Noon. We sought to develop a model that faithfully captured the population dynamics of a non-migratory golden eagle population in western North America, while accounting for the demographic and environmental (process) variation inherent in vital rates. Using data from multiple long-term studies, we parameterized a stage-based matrix projection model and evaluated the contribution of vital rates to asymptotic population growth rates within a life-stage simulation analysis (LSA) framework. With a life history that is characterized by long-lived individuals with relatively low reproductive output, breeding adult survival dominates population dynamics for golden eagles. Thus it is unfortunate that breeding adult survival is the least-represented vital rate estimated in published literature. Simulating reduced survival across stage-classes revealed that a relatively minor (4%) reduction in survival resulted in a growing population to decline. Furthermore, targeting management at bolstering reproductive output is unlikely to compensate for reduced survival. Productivity rates (young fledged per pair) necessary to produce stable ...