Hooded crane (Grus monacha)
|Spanish:||Grulla Monje, Grulla Monjita|
|Size||Length: 100 cm (2)|
|Weight||3.75 kg (3)|
The hooded crane is classified as Vulnerable (VU) on the IUCN Red List 2007 (1) and is listed on Appendix I of CITES (4). It is also listed on Appendices I and II of the Convention on Migratory Species (5).
Bulky-looking compared to other, more elegant cranes, the hooded crane has a slate grey body with a white head and upper neck (2). The primaries, secondaries and tail are black and the legs and feet are nearly black. Its most noticeable feature is the bald, red crown of adults, which has black bristles protruding from it. The crown of juveniles is covered with black and white feathers throughout the first year of life (3).
The hooded crane is known to breed in south-central and southwestern Siberia, and is thought to also breed in north Mongolia. The species migrates to wintering grounds in China, South Korea and Japan, with over 80 percent of the population wintering in Izumi in southern Japan, where an artificial feeding station is funded by the Japanese government (2).
During winter, the hooded crane can be found on wetlands, including marshes, coastal tidal flats, and farmland. During summer, the hooded crane breeds in remote, wooded, upland bogs on hills and river terraces (2), or, in Mongolia, can be found in river valleys and wetlands, gathering in wheat fields in autumn (6) (7).
Maturing at three to four years, hooded cranes move to the breeding grounds in pairs or small flocks between April and May (8). Here, they perform a courtship display, throwing back the head and lifting the beak vertically. Males initiate the display, holding their wings above their backs. Males and females call in unison for some time, with males calling just once for every two female calls. Many crane species engage in the display simultaneously, during which new pairs are formed and old bonds strengthened. Pairs then construct a nest of damp moss, peat, branches, and sedge stalks and leaves. Two eggs are laid by the female and incubated by both sexes for 27 to 30 days. The male defends the nest throughout this time when not incubating. The chicks fledge after 75 days (3) and by August the hooded cranes leave the breeding grounds in family groups. In some areas the hooded crane produces hybrids with the common crane (Grus grus) (8).
The hooded crane eats plants, berries, insects, frogs, roots, seeds and grass. During the winter, 80 percent of the population feeds at the special artificial feeding station in Izumi, Japan, where they are fed cereal grains. As in all cranes species, the white-naped crane is active and is often seen ‘dancing’: flapping the wings, tossing grass and sticks, jumping, running and bowing. As well as being involved in courtship, this is thought to reduce aggression and relieve tension (3).
As with many wetland habitats, the wetlands of South Korea and China are being drained for development and dam-building. Many paddy fields are being converted into cotton fields, which are less suitable as a wintering habitat for the hooded crane. In China, pollution of coastal waters, pesticide poisoning, human disturbance and over-fishing are all threatening this species, but the most serious potential threat comes as a result of the feeding station in Izumi, Japan. Because such high concentrations of hooded crane are found in one area, the species is at risk of disease which could potentially affect up to 80 percent of the population. Some hunting of the hooded crane also occurs, particularly at the breeding grounds (2). In addition, the number of birds in Mongolia during the summer has decreased over the last few years due to fire, overgrazing and drought (6) (7).
There are many protected areas that cover key sites for this bird, including the Mongol Daguur and Numrug Strictly Protected Areas in Mongolia (6) (7), but more protected areas in the Bikin river basin in Russia and in Sucheon Bay in South Korea would be of benefit (2). In addition, this species is listed in the Hunting Law and Red Data Book of Mongolia as a rare species, and therefore hunting of the hooded crane is prohibited in Mongolia (6) (7).
Since the early 1950s, the government of Japan has provided funding to feed cranes in Izumi. At the start there were several hundreds of hooded cranes, but this figure has risen to 8,000 (3). It has been proposed to try to increase the wintering area across Japan, thereby lessening the risk of the whole population being lost to disease should it break out. It is also important to reduce the threats that arise from the Three Gorges Dam across the Yangtze in China. It has caused changes in water flow which alter the surrounding land and prevent migratory fish from spawning (2). A new wintering population was discovered in South Korea in 1996 and the area has since been protected as a Special Nature Reserve (3).
For further information on the hooded crane see:
- BirdLife International. (2001) Threatened Birds of Asia: the BirdLife International Red Data Book. BirdLife International, Cambridge, UK.
Authenticated (20/05/08) by Dr. Sundev Gombobaatar, Associate Professor, Zoology Department, National University of Mongolia. Vice President, Mongolian Ornithological Society.
- Hybridisation: cross-breeding with a different species.
- Primaries: in birds, the outer flight feathers.
- Secondaries: the shorter flight feathers projecting along the inner edge of a bird's wing.
IUCN Red List (July, 2014)