Identification | Breeding | Feeding | Range & Habitat | Migration | Facts
In the east and west, studies of golden eagle populations have found that the number is higher than once believed. In the east, golden eagles use forested areas more frequently and in greater numbers. Young eagles, which were previously unaccounted for, spend the summer in northern Alaska’s remote regions where food is abundant. Read on for more facts about the golden eagle.
- The plumage of the golden eagle explained
- It is usually the largest bird of prey throughout its range
- The golden eagle has a worldwide distribution
- Most golden eagles occur in western North America
- Golden eagles feed on small to medium-sized life mammals
- A golden eagle is often considered a mute bird
- Nest sites are rather variable
- The golden eagle has a long lifespan
- How many golden eagles are there?
- Golden eagle's function in the ecosystem
- Threats to golden eagles
- Is the golden eagle endangered from extinction?
- How does the law protect the golden eagle?
The plumage of the golden eagle explained
Golden eagles get their name from the golden-brown feathers on the nape and sides of their necks. Adult eagles have golden-brown to buffy-brown feathers composed of feathers of varying ages.
Golden eagles continuously molt their plumages. They only replace some feathers of their plumage at a time. Therefore, a bird normally has feathers that are 2 to 3 years old (fading buffy brown) and fresh, newly replaced feathers that are dark to blackish-brown.
It is usually the largest bird of prey throughout its range
Indeed, the golden eagle is usually the largest bird of prey within its range. In terms of size, it is second in size to the huge California condor, with which it overlaps in the condor’s limited range.
Adult golden eagles are most similar in size and appearance to juvenile bald eagles. After the California condor, these two eagles are America’s largest birds of prey.
The bald and golden eagle favor different habitat types. The bald eagle is closely associated with water, while golden eagles are birds of mountainous open arid and semi-arid country in the west. Golden eagles in the east inhabit semi-open mountainous forests interspersed with rocky hillsides.
Both eagle species overlap in many parts of their huge ranges.
Young golden eagles are less confusing as no other large raptor has white wing patches and white on the base of the tail.
The golden eagle has a worldwide distribution
Golden eagles are found in temperate regions of all continents.
They are considered a single species composed of 6 recognized subspecies.
The subspecies in the Americas is known as Aquila chrysoaetus canadensis. It is known as the American golden eagle.
Its worldwide distribution and popularity are evidenced by the fact that the golden eagle is an official national bird in countries such as Albania, Germany, Austria, Mexico, and Kazakhstan.
Most golden eagles occur in western North America
The golden eagle stronghold is in the western half of North America.
There is a separate and small population of golden eagles in eastern North America.
Golden eagles in the west have migratory and year-round resident populations, while all eagles in the east are migratory.
It is estimated that there are 63,000 golden eagles in Canada, the United States, and Mexico. Approximately 5,000 of those occur in the eastern United States and Canada.
Golden eagles feed on small to medium-sized life mammals
The main prey of golden eagles are rabbits, ground squirrels, marmots, and prairie dogs. Occasionally they prey upon larger prey such as wild turkeys, geese, young wild ungulates, and young sheep and goats.
On even more rare occasions, golden eagles have attacked prey much larger than the eagles themselves. Attacking larger prey than usual is perhaps more common in falconry, where eagles are assisted soon after they catch the target prey.
They can also hunt various small prey such as mice, small lizards, and fish in shallow waters.
A golden eagle is often considered a mute bird
The golden eagle is generally silent, giving vocalizations on only a few occasions. Adults vocalize when they meet in the air or in the nest when one bird brings food.
Young birds in the nest are more vocal, giving begging calls when they are hungry and spot one of the parents bringing food.
Nest sites are rather variable
Golden eagles nest in tall trees, cliff ledges, and manmade structures. Nest sites are placed on the substrate more readily available.
In an open country with plenty of cliffs, golden eagles nest on cliffs almost exclusively. The same is true for tall trees.
Communication towers and utility poles have been used by golden eagles for nesting.
When no cliff or other tall structures are available, and prey is abundant, golden eagles nest on the ground on predator-free lake islands or other places inaccessible to land predators.
The golden eagle has a long lifespan
Golden eagles have long lifespans. The oldest individual on record died at the age of 31 years and eight months. It was banded in the State of Utah and later found dead in the same state, according to “Longevity Records of North American Birds,” compiled by the U.S. Geological Survey’s Patuxent Wildlife Research Center in Maryland.
How many golden eagles are there?
According to the “Partners in Flight Science Committee (2021)”, there are approximately 63,000 mature golden eagles living in Canada, the U.S., and Mexico.
Most birds occur in the western half of North America. The golden eagle population in eastern North America is about 5,000 individuals or less.
These population estimates are approximations for landbirds breeding in the U.S. and Canada. The estimates are based on data from the Breeding Bird Survey, which was designed to derive indices of population trend, not measures of population density. (Thogmartin et al. 2006).
Golden eagle’s function in the ecosystem
Golden eagles are top predators that influence the structure and balance of the ecosystem by controlling the abundance, distribution, and diversity of their prey.
Controlling the abundance and diversity of the prey golden eagles regularly feed on has a cascading effect on the food chain.
They feed on other animals or plants that are also maintained in balance by keeping the right type and number of individuals in the ecosystem.
Other top predators have a similar effect helping to maintain a balance in the food chain.
Threats to golden eagles
Shooting, legal and illegal, has been one of the main sources of golden eagle mortality. The main reason for the prosecution was the perceived damage that golden eagles cause to livestock.
Another reason was the demand for feathers and other eagle parts for native American cultural and religious traditions.
In the 1900s, it is estimated that as many as 25,000 golden eagles were legally shot in California and other western states. More recently, in 1971, sheep ranchers hired hunters to eliminate golden eagles where as many as 500 eagles are suspected of having been shot.
The golden eagle is currently protected by law, but illegal hunting continues to be one of the main sources of golden eagle mortality.
Lead poisoning appears to be a considerable source of golden eagle mortality. Eagles consume unrecovered game animals shot with lead ammunition. In some cases, lead sickens the eagle but in others, poisons and kills the bird.
It is estimated that lead poisoning causes about 2–3% of golden eagle deaths in the United States. Low levels of lead poisoning that are not lethal are widespread among golden eagles, but its long-term effect on the eagles is unknown.
Collisions with utility wires, fences, moving cars, and wind turbines are a significant cause of golden eagle injury and death.
Interestingly, collisions with moving vehicles are among the most significant types of collisions. For reference, nearly 100 golden eagles were killed on highways in Wyoming in the winter of 1984–1985.
Collisions with wind turbines are gradually becoming a more significant cause of golden eagle injury and death.
Information on golden eagle collisions collected in 10 wind turbine facilities resulted in 79 individuals killed in a period of 15 years. A disproportionately high number of collisions occurred towards the end of the study period as more turbines were erected.
The 79 eagles killed in the 15-year study is likely an underestimated number because the report of dead eagles depended on incidental finds and voluntary reporting from personnel in these facilities.
A more recent 4-year study from the Altamont Pass Wind Resource area in California revealed that 67 golden eagles were killed each year.
Electrocution has always been a cause of golden eagle mortality. Young birds are disproportionately electrocuted in greater numbers than adults. The reason for this is that young birds are clumsier and are more likely to make contact with two wires and form a circuit at landing or take off.
Wet and windy conditions appear to exacerbate the problem as wet conditions increase electric conductivity and windy conditions often lead to unbalanced landings.
Electrocution also appears more frequent in open habitats with few elevated perches where golden eagles often use utility poles.
In states where golden eagles live, efforts are being made to reduce golden eagles and other large birds’ mortality to electrocution.
Power fixtures are being retrofitted, and new designs are being installed. The results are evident as the number of electrocutions decreased where these measures were implemented.
Is the golden eagle endangered from extinction?
The golden eagle populations are presumably stable. In the United States, the species is not listed as threatened or endangered of extinction at the federal level. Some states list the eagle under various categories of threat.
For instance, Washington and Montana list it as a species of special concern, while Maine, New Hampshire, and New York recognize it as an endangered species.
Canada does not list the golden eagle under any category of threat.
How does the law protect the golden eagle?
In the United States, the golden eagle is protected by the Bald and Golden Eagle Protection Act. Further protection is granted by the Migratory Bird Treaty Act.
At the state level, the golden eagle is protected by specific laws or included on lists of endangered, threatened, or special concern species.
The protection granted by states varies depending on the presence, abundance, or whether the golden eagle nests in the state. Eastern states do not have protection laws because the golden eagle is there only part of the year, during the winter.
In Mexico, federal environmental law monitors and protects more than a thousand different species of birds, of which more than 300 are in some category of protection, including the golden eagle.
In Canada, the golden eagle is not protected by federal law. However, individual provinces provide protection to the golden eagle.