Golden Eagle

The golden eagle (Aquila chrysaetos) is the largest diurnal bird of prey found year-round in the Alps, with a range extending across much of the Northern Hemisphere. In the Aosta Valley, it inhabits almost every valley and is the flagship species amongst the large mountain birds of prey.

The golden eagle is one of the largest diurnal birds of prey in the Northern Hemisphere: its wingspan reaches 200–240 cm, and its weight varies between 3 kg and 7 kg, with marked sexual dimorphism favouring the female, which is significantly larger than the male. The adult’s plumage is dark brown, lighter and more golden on the nape — hence its common name — whilst juveniles have large white patches at the base of the wings and tail, visible even from a distance, which gradually disappear over the first 4–6 years of life until they develop their adult plumage. In flight, it is recognised by its silhouette, with broad wings and primary flight feathers spread ‘like fingers’, a relatively long and slightly rounded tail, and a head that is proportionally small compared to the body.

The species’ range covers much of the Northern Hemisphere, from North America through Eurasia to north-western Africa; in Italy, it is found in all the main mountain ranges (the Alps, the Apennines, and the mountains of Sardinia and Sicily). In the Aosta Valley, the species occupies almost the entire suitable habitat: only the most heavily developed areas and the high-altitude snowfields are unsuitable. The sources consulted regarding regional population numbers do not agree: one recent source mentions around twenty breeding pairs in the Aosta ValleyAosta, whilst another estimates at least 35 permanently occupied territories, with a hypothetical maximum of 40 — a significant discrepancy (almost double), which cannot be resolved using the available sources and is noted here without resolving the contradiction. A more reliable, specific figure – as it relates to a defined area monitored continuously – comes from the Gran Paradiso National Park: 27 pairs recorded, distributed across all the park’s valleys, with 141 alternative nests identified by park rangers’ monitoring.

A pair’s territory comprises a nesting area on rock faces and a series of hunting grounds with little or no woodland, situated on the periphery of the nests; the average size is 50–80 km² in the Aosta ValleyAosta. Contrary to popular belief, which would have them near the summits, the nests are typically found at altitudes of between 1,700 m and 2,200 m; record altitudes of 2,500–2,700 m, reported in the past in the Aosta ValleyAosta, are likely the result of repeated persecution of the more accessible nests, which has driven the species towards more inaccessible sites.

The pair is monogamous and remains stable throughout the individuals’ lives, with long-term fidelity to the same territory; the two partners build and maintain several alternative nests, choosing the most suitable one from year to year. Hunting is opportunistic and often carried out in pairs: the main prey in the Alps are marmots, mountain hares, rock partridges, black grouse and young or weakened chamois and ibex; in winter, when live prey is scarce, the eagle adapts to scavenging on the carcasses of ungulates that have died from the cold or in avalanches. Breeding success is generally low: a single brood per year, almost always with only one fledgling per pair even when more than one egg is laid; in the Aosta ValleyAosta, the average number of young reared by monitored pairs has been rather low in recent years, a figure consistent with observations in other Alpine areas with high population densities.

Globally, the species is classified as “Least Concern” (IUCN Red List, most recent assessment 2021–2022), with a stable or increasing population across most of its range. However, the global picture does not correspond to the legal protection regime applied in Italy, where the golden eagle is a specially protected species under Article 2 of Law 157/1992, listed inAnnex I of the Birds Directive 2009/147/EC and Annex II of the Bern Convention: the law prohibits the killing, capture, possession and deliberate damage to nests and eggs. These two levels — a global conservation status of ‘not at risk’ and strict national legal protection — reflect different situations: the former concerns the health of the species on a global scale, whilst the latter reflects the historical vulnerability of Italian populations, which are now recovering after a long period of direct persecution.

Direct observation is relatively easier than with other mountain birds of prey, thanks to the large, stable territories occupied for decades by the same pair: the rocky cliffs above the tree line, during the middle of the day when thermal currents favour gliding flight, remain the most favourable setting. The Gran Paradiso National Park, with the highest density of breeding pairs amongst Italy’s protected areas, is a key location for observation in the Aosta Valley and Piedmont. The species also features as wildlife to be observed along various routes already published on inalto.org, including the route to the Barmasse Refuge from Maen.

The greatest risk of confusion is with the bearded vulture (Gypaetus barbatus) in juvenile plumage, which is of a comparable size: the most reliable distinguishing feature in flight is the shape of the tail, which is rhomboid and wedge-shaped in the bearded vulture, whilst it is rounded in the golden eagle; furthermore, the golden eagle has a proportionally smaller head and less rectangular wings. With the common buzzard (Buteo buteo), which is much more common and widespread even at low altitudes, confusion is only possible at a great distance: thegolden eagle are significantly larger, and its gliding flight is more powerful and less ‘butterfly-like’.

Fact sheet

Common name: Golden Eagle
Scientific name: Aquila chrysaetos (Linnaeus, 1758)
Species: diurnal bird of prey
Family: Accipitridae (order Accipitriformes)
Distribution: Holarctic — North America, Europe, northern and central Asia, north-western Africa
Habitat: open or semi-wooded mountain environments, tundra and steppe; nests on rock faces or, more rarely, on isolated trees
Diet: carnivorous — small and medium-sized mammals and birds, occasionally reptiles; seasonal scavenging on carrion