Golden eagle: profile of the most imposing bird of prey in the northern hemisphere

Few silhouettes in the sky are as striking as that of the golden eagle (Aquila chrysaetos). With a wingspan that can reach nearly 2.3 meters and a leisurely flight over slopes and rocky outcrops, it is one of the most widespread diurnal birds of prey on the planet and, for many ornithologists, the queen of the mountains of the northern hemisphere.

On the Iberian Peninsula it is a long-familiar presence in mountain ranges and steppes. Beyond our borders, you can find it from the deserts of Mongolia to the tundras of Alaska. This is its profile.

Identification: how to recognize a golden eagle

The golden eagle is a large bird of prey belonging to the family Accipitridae. Adults have a uniform dark brown plumage with a golden nape patch that gives it its name (chrysaetos means “golden eagle” in Greek).

Key features for identification:

• Body length: 66-102 cm.
• Wingspan: 180-234 cm, with females larger than males.
• Weight: 2.8-4.5 kg for males; 3.8-6.7 kg for females.
• Tail: long, with faint grey bands in adults and a dark terminal band.
• Legs feathered down to the toes, a trait that distinguishes it from other raptors such as the white-tailed eagle.

Juveniles are recognized by the white patches at the base of the tail and on the underside of the wings. This pattern gradually disappears until adult plumage is reached at around 5 years of age.

As for longevity, in the wild it frequently exceeds 20 years, and in captivity individuals over 40 years have been documented.

Habitat and distribution: a holarctic raptor

The golden eagle is a holarctic species: it occupies much of the northern hemisphere. Its range covers Europe, North Africa, much of Asia and North America, from Mexico to Alaska.

It prefers open or semi-open terrain with rugged relief: mountains, canyons, steppe plateaus and moorlands. It needs rocky cliffs or large trees for nesting and clear space for hunting in flight.

In Spain, whose population is one of the most important in western Europe, it is estimated at around 1,500-1,700 breeding pairs according to censuses coordinated by SEO/BirdLife. It is present in nearly all peninsular regions, with dense nuclei in Castile and León, Aragon, Castile-La Mancha and Andalusia.

It avoids dense forests and densely populated urban areas. Each pair defends a territory that can range from 20 to 200 km² depending on prey availability.

Feeding: a versatile hunter

It is an opportunistic predator with a very broad diet. Its typical prey are medium-sized mammals: rabbits, hares, marmots, young foxes and ungulate calves. It also hunts medium to large birds such as partridges, pigeons or corvids, and reptiles such as ocellated lizards and snakes.

In winter, when live prey is scarce, it does not reject carrion. This opportunistic behavior allows it to survive in areas where other raptors could not.

The most common hunting technique is a low- to mid-altitude searching flight, with rapid dives onto the prey. It can reach 240-320 km/h in a dive, a figure comparable to that of the peregrine falcon over short distances. Its talons exert an estimated pressure of more than 400 psi, enough to kill prey of up to 4-5 kg.

Reproduction: pairs faithful to their territory

Pairs are monogamous and territorial, and usually maintain the bond for years. They occupy several alternative nests within the same territory, called eyries, which they reuse and enlarge season after season. Some historic nests reach 2 meters in diameter and weigh more than 100 kg.

The typical breeding calendar on the Iberian Peninsula:

• Courtship and nest preparation: January-February.
• Laying: February-March, usually 2 eggs (rarely 1 or 3).
• Incubation: 41-45 days, mainly by the female.
• Time in the nest: 65-80 days.
• Independence: juveniles depend on the adults for up to 3-4 months after fledging.

Siblicide is common: the older chick kills the younger one in the first weeks, especially when food availability is low. That is why, even though two eggs are laid, usually only one chick survives per season.

Conservation status: least concern, but with local threats

The IUCN classifies the golden eagle as Least Concern (LC) on a global scale, with a world population estimated at more than 200,000 individuals. In Spain it is listed as “Of special interest” in the Spanish List of Wild Species under Special Protection of MITECO, with a favorable status in most of the territory.

The main threats are local but persistent:

• Electrocution and collision with power lines, one of the most frequent causes of unnatural mortality.
• Poisoning from illegal baits aimed at carnivores.
• Collision with wind turbines in poorly located wind farms.
• Human disturbance at the nest during breeding (climbing, drones, intrusive photography).
• Habitat loss due to urbanization and agricultural transformation.

Programs such as the correction of dangerous power lines promoted by MITECO and the autonomous communities have reduced mortality in pilot areas. If you are interested in the recovery of other Iberian raptors, there is the case of the bearded vulture and its return to the Pyrenees, another partial success story.

Verifiable curiosities

• It is the national bird of countries as different as Mexico, Germany, Austria and Kazakhstan.
• In Mongolia and Kyrgyzstan there is an age-old tradition of falconry with golden eagles, practiced by Kazakh hunters (the berkutchi), recognized by UNESCO as Intangible Cultural Heritage.
• It can spot a hare from more than 2 kilometers away thanks to a visual acuity estimated at 4-8 times that of humans.
• It is not a strictly migratory bird: Iberian populations are sedentary, while those of northern Europe and North America make seasonal movements.

Frequently asked questions

How long does a golden eagle live? In the wild, its average life expectancy exceeds 20 years once it reaches adulthood. In captivity, individuals of more than 40 years have been recorded.

Is it dangerous to people? No. There are no documented attacks with adult human victims. It may defend its nest with intimidating flights if you get too close, but avoid contact.

Can it carry off a lamb or a small dog? Occasionally it preys on newborn lambs or kids, especially in mountain areas. An adult in good health can carry about 2-3 kg in flight; larger prey it consumes on site.

Can you keep a golden eagle as a pet? No. It is a protected species in Spain and in most of its range. Keeping one is only legal within regulated falconry, with specific permits and specimens of certified origin.

How does it differ from the Spanish imperial eagle? The Spanish imperial eagle (Aquila adalberti) has very marked white shoulders in adults and lives in dehesas and plains. The golden eagle is darker, without white on the shoulders, and prefers mountainous areas.