Hen harriers are almost owl-like in their facial appearance, which distinguishes them from other hawks. The face shape helps the harriers to detect small mammals and birds concealed in vegetation, as they rely on sound as well as sight to pinpoint prey. During the breeding season, males perform a spectacular sky dance, with a series of steep climbs, twists and rolls. Hen harriers exhibit a degree of polygyny, nesting in loose colonies, with males simultaneously raising several broods with as many as seven females.

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