Animal spotlight: 7 facts about North American eagles

From Bald Eagle Appreciation Days in Wisconsin to soaring Golden Eagles as a tradition at Auburn University, North American eagles are viewed as stately and powerful creatures. However, these two resident eagles of North America have not survived without a struggle.

Officials removed Bald Eagles from the US federal list of threatened and endangered species in 2007 after years of illegal hunting and habitat and food destruction diminished the population.  Though Golden Eagles are not currently on a watch list, human impact causes an estimated 70 percent of Golden Eagle deaths. Fortunately, the Bald and Golden Eagle Protection Act of 1940 protects both eagles.

Learn more about the Golden Eagle and Bald Eagle in our factsheet.

1. Room to roam 

Golden Eagles living in eastern North America have home ranges two to ten times the size of Golden Eagles elsewhere. Scientists think this is because habitat in eastern North America is lower quality, with less prey and fewer nesting and roosting sites, forcing eagle to range over larger areas to find enough resources. Climate change and energy development are expected to hit eagles in this region especially hard.

2. Help from the public

Analysis of “citizen science” data shows that approximately 1,300 Golden Eagles migrate along a single ridge in Pennsylvania every year. Because Golden Eagles tend to be spread out across large areas, occurring at low densities, counts like this can be crucial for monitoring how their populations are doing.

3. Weather advisory 

Researchers studying the effects of weather on Golden Eagle migration were surprised to learn that older eagles did not cover more ground than younger eagles, despite their greater experience. Instead, older eagles migrated in poorer weather conditions and traveled more slowly. Young eagles typically aren’t breeding yet, while older birds need to start heading north in time to reclaim their territories on their breeding grounds and start nesting, so they can’t be as picky about when they start out.

4. Peaceful coexistence 

Golden Eagles are sensitive to human recreation near their nest sites, and a study showed that it isn’t only the volume of people passing through that affects them — the overall density of the trail network near their nests matters, too. Land managers need to take both of these factors into account to make sure that hikers and eagles can coexist.

5.  California conservation

Bald Eagles were extirpated from California’s Channel Islands in the 1960s but have been reintroduced there in recent decades. Knowing what the reintroduced eagles are eating is key to helping them thrive, and analysis of prey remains from eagle nests and isotope ratios in eagle feathers showed that their diet includes a lot of seabirds such as gulls and terns. It appears that seabird conservation efforts in the Channel Islands are benefiting the entire food chain.

6. Aquatic birds

When hunting for fish, Bald Eagles can swim by paddling their wings in powerful strokes after landing in the water. This type of wing paddling, along with plunge diving and hint feet paddling in other types of birds, developed from ancestors of airborne birds as the species learned to adapt to aquatic habits.

7. National animal

The Bald Eagle in the United States was once threatened with extinction as a result of hunting and poisoning. Due to its protection the Bald and Golden Eagle Protection Act of 1940, their population has abundantly increased. Only 16% of national animals are receiving protection within the country where they are the national symbol. If population trends persist, over half of these symbols may face future extinction.

Featured image credit: Bald Eagle Perched Raptor by skeeze, CC0 via Pixabay.