Eastern Marsh Harrier
Encyclopedia
The Eastern Marsh Harrier (Circus spilonotus) 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
(Circus aeruginosus) but is now usually classified as a separate species. It has two subspecies
: C. s. spilonotus in eastern Asia
and C. s. spilothorax (Papuan Harrier
, perhaps a separate species) in New Guinea
.
is variable; typically the head, breast, back and wing-coverts are blackish with pale streaks. The rest of the wing is grey with black wingtips and a white front edge. The tail is grey, the rump is white and the underparts are mostly white. The female is dark brown with buff streaking on the head and underparts. The rump is often whitish and the tail has dark bars. Young birds are dark brown with buff on the head and a pale patch on the underwing.
It is usually silent but has a mewing call which is most often uttered at roost sites.
apart from the Papuan Harrier which is sedentary. The breeding range covers north-east China, Mongolia
and south-east Siberia
(as far west as Lake Baikal
) with small numbers in northern Japan
(Hokkaidō
and northern Honshū
). There is some overlap with Western Marsh Harrier around Lake Baikal and interbreeding has taken place.
The wintering range includes southern China, Taiwan
, Korea
, southern Japan, north-east India, Bangladesh
and South-east Asia as far south as the Philippines
, Borneo
and Sumatra
. Large numbers of birds migrate along the Chinese coast with thousands passing through sites like Beidaihe
during the autumn.
Its preferred habitat is open country including marshland, paddy field
s and grassland
.
The breeding season
begins in April. The nest is made of sticks and built on the ground, usually in a reedbed. Four to seven eggs are laid which are incubated for 33 to 48 days. The young birds fledge
after 35 to 40 days.
Bird of prey
Birds of prey are birds that hunt for food primarily on the wing, using their keen senses, especially vision. They are defined as birds that primarily hunt vertebrates, including other birds. Their talons and beaks tend to be relatively large, powerful and adapted for tearing and/or piercing flesh....
belonging to the marsh harrier
Marsh harrier
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...
group of harriers
Harrier (bird)
A harrier is any of the several species of diurnal hawks forming the Circinae sub-family of the Accipitridae family of birds of prey. Harriers characteristically hunt by flying low over open ground, feeding on small mammals, reptiles, or birds....
. It was previously considered to be conspecific with the Western Marsh Harrier
Western Marsh Harrier
The Western Marsh-harrier is a mid-sized harrier, a bird of prey from temperate and subtropical western Eurasia and adjacent Africa. It is also known as the Eurasian Marsh-harrier....
(Circus aeruginosus) but is now usually classified as a separate species. It has two subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
: C. s. spilonotus in eastern Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
and C. s. spilothorax (Papuan Harrier
Papuan Harrier
The Papuan Harrier is a bird of prey native to New Guinea which belongs to the harrier genus Circus. It is commonly classified as a subspecies of the Eastern Marsh Harrier of eastern Asia...
, perhaps a separate species) in New Guinea
New Guinea
New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...
.
Description
It is 48 to 58 cm long with a wingspan of 113 to 137 cm; like most birds of prey, the female is usually larger than the male. The male's plumagePlumage
Plumage refers both to the layer of feathers that cover a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage vary between species and subspecies and can also vary between different age classes, sexes, and season. Within species there can also be a...
is variable; typically the head, breast, back and wing-coverts are blackish with pale streaks. The rest of the wing is grey with black wingtips and a white front edge. The tail is grey, the rump is white and the underparts are mostly white. The female is dark brown with buff streaking on the head and underparts. The rump is often whitish and the tail has dark bars. Young birds are dark brown with buff on the head and a pale patch on the underwing.
It is usually silent but has a mewing call which is most often uttered at roost sites.
Distribution and habitat
Eastern Marsh Harriers are generally migratoryBird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
apart from the Papuan Harrier which is sedentary. The breeding range covers north-east China, Mongolia
Mongolia
Mongolia is a landlocked country in East and Central Asia. It is bordered by Russia to the north and China to the south, east and west. Although Mongolia does not share a border with Kazakhstan, its western-most point is only from Kazakhstan's eastern tip. Ulan Bator, the capital and largest...
and south-east Siberia
Siberia
Siberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...
(as far west as Lake Baikal
Lake Baikal
Lake Baikal is the world's oldest at 30 million years old and deepest lake with an average depth of 744.4 metres.Located in the south of the Russian region of Siberia, between Irkutsk Oblast to the northwest and the Buryat Republic to the southeast, it is the most voluminous freshwater lake in the...
) with small numbers in northern Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
(Hokkaidō
Hokkaido
, formerly known as Ezo, Yezo, Yeso, or Yesso, is Japan's second largest island; it is also the largest and northernmost of Japan's 47 prefectural-level subdivisions. The Tsugaru Strait separates Hokkaido from Honshu, although the two islands are connected by the underwater railway Seikan Tunnel...
and northern Honshū
Honshu
is the largest island of Japan. The nation's main island, it is south of Hokkaido across the Tsugaru Strait, north of Shikoku across the Inland Sea, and northeast of Kyushu across the Kanmon Strait...
). There is some overlap with Western Marsh Harrier around Lake Baikal and interbreeding has taken place.
The wintering range includes southern China, Taiwan
Taiwan
Taiwan , also known, especially in the past, as Formosa , is the largest island of the same-named island group of East Asia in the western Pacific Ocean and located off the southeastern coast of mainland China. The island forms over 99% of the current territory of the Republic of China following...
, Korea
Korea
Korea ) is an East Asian geographic region that is currently divided into two separate sovereign states — North Korea and South Korea. Located on the Korean Peninsula, Korea is bordered by the People's Republic of China to the northwest, Russia to the northeast, and is separated from Japan to the...
, southern Japan, north-east India, Bangladesh
Bangladesh
Bangladesh , officially the People's Republic of Bangladesh is a sovereign state located in South Asia. It is bordered by India on all sides except for a small border with Burma to the far southeast and by the Bay of Bengal to the south...
and South-east Asia as far south as the Philippines
Philippines
The Philippines , officially known as the Republic of the Philippines , is a country in Southeast Asia in the western Pacific Ocean. To its north across the Luzon Strait lies Taiwan. West across the South China Sea sits Vietnam...
, Borneo
Borneo
Borneo is the third largest island in the world and is located north of Java Island, Indonesia, at the geographic centre of Maritime Southeast Asia....
and Sumatra
Sumatra
Sumatra is an island in western Indonesia, westernmost of the Sunda Islands. It is the largest island entirely in Indonesia , and the sixth largest island in the world at 473,481 km2 with a population of 50,365,538...
. Large numbers of birds migrate along the Chinese coast with thousands passing through sites like Beidaihe
Beidaihe
Beidaihe District is a district in Qinhuangdao municipality, Hebei province on the coast of the Bohai Sea in North China. It has an area of 70.14 square kilometers and a population of 66,000. is also known as a birding haven. The Beidaihe Beach Resort stretches 10 km from east to west, from...
during the autumn.
Its preferred habitat is open country including marshland, paddy field
Paddy field
A paddy field is a flooded parcel of arable land used for growing rice and other semiaquatic crops. Paddy fields are a typical feature of rice farming in east, south and southeast Asia. Paddies can be built into steep hillsides as terraces and adjacent to depressed or steeply sloped features such...
s and grassland
Grassland
Grasslands are areas where the vegetation is dominated by grasses and other herbaceous plants . However, sedge and rush families can also be found. Grasslands occur naturally on all continents except Antarctica...
.
Diet and reproduction
While hunting it flies low over the ground with the wings held in a shallow V-shape. Its prey includes small mammals, birds and frogs.The breeding season
Breeding season
The breeding season is the most suitable season, usually with favourable conditions and abundant food and water, for breeding among some wild animals and birds . Species with a breeding season have naturally evolved to have sexual intercourse during a certain time of year in order to achieve the...
begins in April. The nest is made of sticks and built on the ground, usually in a reedbed. Four to seven eggs are laid which are incubated for 33 to 48 days. The young birds fledge
Fledge
Fledge is the stage in a young bird's life when the feathers and wing muscles are sufficiently developed for flight. It also describes the act of a chick's parents raising it to a fully grown state...
after 35 to 40 days.