Most long-established pairs of golden eagles use a range of different eyries. Some tend to alternate between two or three; others, particularly in areas with suitable crags around mature forestry, may have many more.
Disturbance from a previous season may force a pair to move to a different nest, particularly if they have failed to rear young.
On occasion, an eyrie may be occupied that is close to the boundary of a pair’s hunting area. If another young duo is trying to establish territory close by, this helps to ensure the newcomers are aware that the ground is already taken.
Alternating nest sites helps to minimise parasitic burden, given that many parasites can overwinter in our increasingly mild, wet climate. Severe storms leading to nest damage and partial collapse close to the laying period may also force a pair to relocate.
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Main image: Golden eagle. © Sylvain Cordier/Getty