The marsh harriers are birds of prey of the harrier subfamily. They are medium-sized raptors and the largest and broadest-winged harriers. Most of them are associated with marshland and dense reedbeds. They are found almost worldwide, excluding only the Americas.
Until recently two species were generally recognized: the marsh harrier (Circus aeruginosus) and the African marsh harrier (C. ranivorus). The marsh harrier is now usually split into several species, sometimes as many as six. These are the western marsh harrier (C. aeruginosus), eastern marsh harrier (C. spilonotus), Papuan harrier (C. spilonotus spilothorax or C. spilothorax), swamp harrier (C. approximans), Réunion harrier (C. maillardi maillardi or C. maillardi) and Madagascar marsh harrier (C. maillardi macrosceles or C. macrosceles).
At the beginning of the 20th century, the marsh harrier was hunted to extinction in the United Kingdom. [1] After being reintroduced from other regions, its population steadily increased until DDT threatened it, along with other raptors, in the 1950s and 1960s. Since, the population has slowly and steadily increased.
The western marsh harrier (Circus aeruginosus), often simply called the marsh harrier, breeds widely across Europe and Asia. It is migratory except in the mildest regions, and winters mainly in Africa. It hunts small mammals, frogs, fish, insects and birds, surprising them as it drifts low over fields and reedbeds. Its long legs allow it to pluck frogs and fish from the water mid-swoop. The western marsh harrier is a typical harrier, with long wings held in a shallow V in its low flight. It also resembles other harriers in having distinct male and female plumages, but its plumages are quite different from those of its relatives. The male has wings with grey and brown sections and black wingtips. Its head, tail and underparts are greyish, except for the chestnut belly. The female is mainly brown with a cream crown and cream leading edge to her wings. It is 19–22 inches long and weighs 1–2 lbs. [1]
The eastern marsh harrier (C. spilonotus) breeds in the grasslands and wetlands of southern Siberia, northern Mongolia, north-east China, Manchuria and Japan, and migrates for the northern winter to South-east Asia, the Philippines and northern Borneo.
Like all marsh harriers, it favours open, wet environments, and is frequently seen drifting low over rice fields, interspersing long, watchful circling glides with two or three slow, powerful wingbeats. Two subspecies are recognised: C. s. spilonotus of east Asia, and C. s. spilothorax, of New Guinea and the islands nearby, which is sometimes thought to be a separate species and is often called the Papuan harrier .
The swamp harrier (C. approximans) at about 50 to 58 cm is slightly larger than C. spilonotus, often a little darker, and has less heavily barred wings and tail. It is commonly found in suitable habitat anywhere in Australasia, particularly in the higher rainfall areas to the east, south-east, and south-west, of Australia and throughout New Zealand, but also in the tropical north of Australia and the island groups of New Caledonia, Vanuatu, Fiji, Tonga and the Society Islands. It is also known as the Australasian harrier or Pacific marsh harrier.
The Madagascar marsh harrier or Madagascar harrier (C. maillardi) is found on the Indian Ocean islands of Madagascar, Réunion and the Comoros. It is sometimes split into two species: Madagascar harrier (Circus macrosceles) and Réunion harrier (C. maillardi).
The African marsh harrier (C. ranivorus) is a distinct non-migratory species that has not usually been included as a subspecies of C. aeruginosus. It inhabits southern and eastern Africa.
A harrier is any of the several species of diurnal hawks sometimes placed in the subfamily Circinae of the bird of prey family Accipitridae. Harriers characteristically hunt by flying low over open ground, feeding on small mammals, reptiles, or birds. The young of the species are sometimes referred to as ring-tail harriers. They are distinctive with long wings, a long narrow tail, the slow and low flight over grasslands and skull peculiarities. The harriers are thought to have diversified with the expansion of grasslands and the emergence of C4 grasses about 6 to 8 million years ago during the Late Miocene and Pliocene.
The hen harrier is a bird of prey. It breeds in Eurasia. The term "hen harrier" refers to its former habit of preying on free-ranging fowl.
Montagu's harrier (Circus pygargus) is a migratory bird of prey of the harrier family. Its common name commemorates the British naturalist George Montagu.
The pallid harrier is a migratory bird of prey of the harrier subfamily. The scientific name is derived from the Ancient Greek. Circus is from kirkos (circle), referring to a bird of prey named for its circling flight, and macrourus is "long-tailed", from makros (long) and -ouros (-tailed).
The northern harrier, also known as the marsh hawk or ring-tailed hawk, is a bird of prey. It breeds throughout the northern parts of the northern hemisphere in Canada and the northernmost USA.
The western marsh harrier 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, the Papuan harrier of eastern Asia and the Wallacea, the swamp harrier of Australasia and the Madagascar marsh harrier of the western Indian Ocean islands.
The eastern marsh harrier is a bird of prey belonging to the marsh harrier group of harriers. It was previously considered to be conspecific with the western marsh harrier but is now usually classified as a separate species. It has two subspecies: C. s. spilonotus in eastern Asia and C. s. spilothorax in New Guinea.
The swamp harrier, also known as the Australasian marsh harrier or Australasian harrier, is a large, slim bird of prey widely distributed across Australasia. In New Zealand, it is also known by the Māori name kāhu. It arrived in New Zealand within the last 700 years, replacing the larger species, the extinct New Zealand endemic Eyles's harrier.
The little bittern or common little bittern is a wading bird in the heron family, Ardeidae. Ixobrychus is from Ancient Greek ixias, a reed-like plant and brukhomai 'to bellow', and minutus is Latin for 'small'.
Eyles's harrier is an extinct bird of prey that was endemic to New Zealand.
The Malagasy harrier is a bird of prey belonging to the marsh harrier group of harriers. It inhabits Madagascar and the Comoro Islands in the Indian Ocean. It was formerly regarded as a subspecies of the Réunion harrier but is increasingly treated as a separate species. It is also known as the Madagascar harrier, Madagascar marsh harrier or Malagasy marsh harrier.
The Réunion harrier, also known as Réunion marsh harrier, is a species of bird of prey belonging to the marsh harrier group of harriers. It is now found only on the Indian Ocean island of Réunion, although fossil material from Mauritius has been referred to this species. It is known locally as the papangue or pied jaune. The Malagasy harrier of Madagascar and the Comoro Islands was previously treated as a subspecies of this bird but is increasingly regarded as a separate species. The Réunion harrier appears to be declining in numbers and it is classed as an endangered species.
The African marsh harrier is a bird of prey belonging to the harrier genus Circus. It is largely resident in wetland habitats in southern, central and eastern Africa from South Africa north to South Sudan.
The Malagasy coucal or Madagascar coucal is a species of cuckoo in the family Cuculidae. It is found in Madagascar and in the Seychelles, where it occurs on Aldabra and was formerly present on Assumption Island and Cosmoledo. Its natural habitats are dense vegetation in subtropical or tropical moist lowland forests, mangrove forests, rough grassland, marshes and reedbeds.
David John Baker-Gabb is a New Zealand and Australian ornithologist. He is best known for his work on Australian birds of prey and the birds of Australia, New Zealand and Oceania. He also served from 1993 to 1997 as director of the Royal Australasian Ornithologists Union.