Golden Eagles in Coastal Southern California

Science Center Objects

The status of the golden eagle (Aquila chrysaetos) in coastal southern California is unclear. To address this knowledge gap, Dr. Robert Fisher in collaboration with local, State and other Federal agencies begin a multi-year survey and tracking program of golden eagles to address questions regarding habitat use, movement behavior, nest occupancy, genetic population structure, and human impacts on eagles. Results from this study will help provide managers with information on the location and status of important nesting and foraging areas.

Populations of golden eagles in California are typically comprised of resident or migratory breeders, resident or migratory non-breeders (for example, adult floaters or subadults), and seasonal itinerants. A better understanding of the current distribution, status, foraging requirements, and population characteristics of golden eagles is needed to identify and effectively manage golden eagle habitat and threats/stressors to each nesting territory in coastal southern California.

Threats such as urban development, recreational activity, fire, or wind energy production may impact eagles differently depending upon habitat selection, the behaviors in which they engage in different parts of the landscape, and the vertical component of space use associated with these behaviors.

Using a combination of population surveys, biotelemetry methods, genetic sampling and nest camera monitoring, this study will examine the relationships between human use and territory occupancy, nesting success, and movements of golden eagles in coastal southern California. We will also explore the genetic distinctiveness of the populations relative to other sampled populations in western North America.

We intend to conduct our research with these specific questions in mind:

  1. What are the population dynamics of golden eagles in coastal southern California?
  2. Is the local breeding population sustained by locally produced eagles or immigrants from other areas?
  3. How does human use (e.g., land-use, renewables development, recreational activity) influence occupancy of nesting territories, nesting success, and movements?
  4. What are the primary foraging areas used by resident eagles in areas designated for future development?