What happens to eagles after rehab?

There are many ways for an eagle to suffer a human-caused death. Electrocution, lead poisoning, vehicle collisions, or being shot, to name a few. Some of these deaths are “offset” through a provision within the Bald and Golden Eagle Protection Act of 1962 (BGEPA) that requires eagles to be replaced when they are removed from the population by certain human actions. A recent study published in the Journal of Raptor Research, titled “Post-release Survival of Golden Eagles in Western North America Following Clinical Rehabilitation from Injury and Disease,” found that releasing rehabilitated Golden Eagles (Aquila chrysaetos) back into the wild could be an effective means of compensating for eagle deaths that occur as a result of otherwise legal actions, such as those associated with energy infrastructure. These results are part of a continuous effort to try and stabilize Golden Eagle populations throughout their range and understand the efficacy of rehabilitation efforts for the species in general.  

A key provision within the BGEPA refers to what is called “incidental take.” This acknowledges that injury, death, or disturbance of eagles may result from technically legal human activities. Such “take” is accepted as a matter of practicality, up to a point. For example, electrical companies must develop and implement formal protection plans to limit take to the greatest extent possible in order to avoid persecution if eagles suffer electrocutions from their equipment. With such a plan, a utility company can obtain a permit from the U.S. Fish and Wildlife Service that allows limited incidental take. However, these takes must be offset, which is where rehabilitation could come in. 

Lead author on the paper, Robert Murphy, in collaboration with many dedicated wildlife rehabilitators and biologists from several western wildlife agencies and conservation organizations, aimed to determine whether releasing rehabilitated Golden Eagles can indeed offset wild eagle deaths. The team fitted 27 rehabilitated Golden Eagles with satellite transmitters just before releasing the eagles near where they had been found in several western states. 

Fifteen of the 27 eagles died within the first year of release. Fates of three were unknown. The cause of death was confirmed for most of these eagles, and included electrocution, vehicle collision, wind turbine collision, shooting, lead poisoning, rodenticide poisoning, and starvation. None of the 10 breeding-age eagles that survived multiple years exhibited signs of inhabiting nesting territories while being monitored by the research team, except for one, although only for part of a season. Two other eagles struck out on bizarre journeys, moving up to 5,300 miles in atypical directions during a time of year that most North American Golden Eagles stay put. Both eagles died. Head trauma was the suspected reason for these movements, as both birds were brought to rehabilitation centers after being hit by cars. Although starvation was the most frequent mortality factor for the released eagles, it is not a common cause of death among wild Golden Eagles.

Based on analysis of their data to estimate eagle survival, the team reported that 3.5 rehabilitated individuals would need to be released to amount to one wild individual, to match parameters for ideal population health. Rehabilitated eagles may have a lower chance of survival for many reasons. Following release, the eagles could still be physically compromised to a degree that is not apparent to rehabilitators or veterinarians. In addition to reduced likelihood of survival, this might hamper their ability to locate and capture prey, find and breed with mates, defend nesting territories, migrate, or otherwise succeed as fit participants of the population. 

The results of this study provide needed insight into the fate of rehabilitated Golden Eagles. In Murphy’s opinion this research is important because “substantial effort and money is invested in rehabilitation, and these centers want to know the fate of the raptors they’ve worked hard to save.” He urges more research on the breeding success of rehabilitated eagles, to better understand how these individuals participate in population growth. Golden Eagle populations are likely to decline in western North America as causes of death become more prevalent in tandem with human development. Golden Eagles are top predators, and their continued presence on the landscape impacts holistic ecosystem health. Finding a way to replace the eagles that die from anthropogenic causes is about more than making up for what we’ve done — it’s about developing wildlife-friendly infrastructure, continuing to invest in education and policy to reduce eagle shootings, restricting poison usage, and prioritizing research that investigates the long-term outcomes of these efforts. 


 

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Paper:

Murphy et al. (2025). Post-release Survival of Golden Eagles in Western North America Following Clinical Rehabilitation from Injury and Disease. Journal of Raptor Research, 59(4):1-10. 
DOI: 10.3356/jrr2469

Notes to Editor:

1. The Journal of Raptor Research (JRR) is an international scientific journal dedicated entirely to the dissemination of information about birds of prey. Established in 1967, JRR has published peer-reviewed research on raptor ecology, behavior, life history, conservation, and techniques. JRR is available quarterly to members in electronic and paper format.

2. The Raptor Research Foundation (RRF) is the world’s largest professional society for raptor researchers and conservationists. Founded in 1966 as a non-profit organization, our primary goal is the accumulation and dissemination of scientific information about raptors. The Foundation organizes annual scientific conferences and provides competitive grants & awards for student researchers & conservationists. The Foundation also provides support & networking opportunities for students & early career raptor researchers.