Molecular Conservation Genetics of Golden Eagles in Western North America

The golden eagle Aquila chrysaetos is widely distributed throughout its historical range in the Northern Hemisphere. According to the International Union for the Conservation of Nature (IUCN) 2006 Red List, global populations are stable and the species is classified as ‘least concern.’ However, the Wildlife Research Institute has determined that eagle populations in San Diego County have decreased in number over the past 30 years due to habitat loss and hunting. These golden eagles appear to be more closely related to birds in Baja California, Mexico than to animals in the continental United States and Canada and contain a unique eye-color variant not found anywhere else in the species’ range.

In addition, a telemetry study conducted by Dr. Grainger Hunt at University of California, Santa Cruz showed that wind turbine blade strikes are the most frequent cause of eagle death, followed by electrocutions on utility lines. At least three-quarters of all eagle fatalities detected during his ongoing study in central California were human related.

These observations prompt the need to carry out population genetic studies using microsatellite DNA markers. A genomic library enriched for microsatellites will be made and screened at CRES. One hundred positive clones will be sequenced and assayed. Twenty-five highly polymorphic markers will be selected for genotyping. These analyses will be carried out on DNA from 200 animals collected from at least five localities in western North America, and the geographic patterns of genetic variation will be used to measure differentiation within and between populations and to assist in the definition of future conservation units.