Habitat and distribution

The Golden Eagle is a generalist species, a bird of prey that occurs throughout the entire northern hemisphere. The species has been able to adapt to a spectrum of different environmental conditions and today inhabits various open and semi-open landscapes . These landscapes range from the higher areas of the European and Asian mountains to the tundra landscapes of northern Asia to steppelands and to the almost desert like landscapes of California, Mexiko and North Africa.

The present densities of Golden Eagle populations vary greatly, depending on the locality. Persecution by humans has caused local extinctions in previously inhabited areas. In earlier times the species was more widely distributed throughout Europe. Continuous heavy persecution, together with significant changes to the landscape, have caused the Golden Eagle to disappear from many of it is former haunts in Middle Europe. This is true even for the Alps, where populations suffered major losses until the beginning of the 20th Century, sometimes bringing them to the border of extinction.

 



Golden Eagles are not very particular in their habitat demands. They are dependent mainly upon a need for undisturbed nesting sites and the presence of sufficient open or semi-open landscape that can provide a good supply of prey animals. The eagles are territorial, their breeding territories covering between 30 and 100 km². The size of the territory is largely dependent upon the structure of the landscape and the availability of prey, so it varies considerably according to the habitat type.

Over the major part of its distribution, the Golden Eagles maintain their territory throughout the year. Only in the far northern corners of their range (eg NE Finland or Alaska) do they leave their normal territories to travel further south for the winter. In contrast to the breeding adults, non-breeding birds frequently undertake long migrations, particularly in the earliest years of their lives. However, even these individuals tend to return eventually to the area where they were born, as evidenced by sigtings of ringed birds.

 

The distribution of the Golden Eagle is after del Hoyo et al. (1991), digitised as part of the Project "Global Register of Migrating Species - GROMS"
(with kind permission of Klaus Riede).



Nesting sites

Golden Eagles build very large, very robust nests designed to last more than one year. Thus they need to find good nesting sites, such as spacious cliff ledges or strong old trees. In the Alps, most of the nests are built on rock ledges. However, in situations of increasing population size, for example in Swizerland, there is a tendency towards more tree nests.

Deciding factors in determining the nest site include, on the one hand, the relation of the site to sources of food, and, on the other hand, the dynamics of the surrounding air currents. In the Alps, nests are usually built on cliffs below the tree line. This makes return with a heavy prey item, usually caught higher up, much more manageable. For successful breeding, a relatively undisturbed nesting site is desirable. Any disturbance that occurs at a nest site can mean that the nest will be avoided in future years.

 

FGolden Eagles nesting on cliffs use spacious, sheltered sites (Foto: © NPS K. Bliem)
Golden Eagle nests in trees require old trees with strong branches (Foto © NPS K. Bliem)


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