Western Marsh Harrier

The western marsh harrier (Circus aeruginosus) is a large harrier, a bird of prey from temperate and subtropical western Eurasia and adjacent Africa. It is also known as the Eurasian marsh harrier. Formerly, a number of relatives were included in C. aeruginosus, which was then known as "marsh harrier". The related taxa are now generally considered to be separate species: the eastern marsh harrier (C. spilonotus), the Papuan harrier (C. spilothorax) of eastern Asia and the Wallacea, the swamp harrier (C. approximans) of Australasia and the Madagascar marsh harrier (C. maillardi) of the western Indian Ocean islands. The western marsh harrier is often divided into two subspecies, the widely migratory C. a. aeruginosus which is found across most of its range, and C. a. harterti which is resident all-year in north-west Africa. Taxonomy The western marsh harrier was formally described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae under the binomial name Falco aeruginosus. Linnaeus specified the locality as Europe but restricted this to Sweden in 1761. The western marsh harrier is now placed in the genus Circus that was introduced by the French naturalist Bernard Germain de Lacépède in 1799. The genus name Circus is derived from the Ancient Greek kirkos, referring to a bird of prey named for its circling flight (kirkos, "circle"), probably the hen harrier. The specific aeruginosus is Latin for "rusty". Two subspecies are recognised: C. a. aeruginosus (Linnaeus, 1758) – breeding in Europe and the Middle East to central Asia south Europe, Africa, south Asia; wintering in south Europe, Africa and south Asia C. a. harterti Zedlitz, 1914 – resident in northwest Africa