White-breasted Sea Eagle, White-bellied Sea Eagle (flight sequence)

Description:

Sequence of photos shot in rapid succession and presented in order. The wings are modified when gliding so that they rise from the body at an angle, but are closer to horizontal further along the wingspan. In silhouette, the comparatively long neck, head and beak stick out from the front almost as far as the tail does behind. For active flight, the white-bellied sea eagle alternates strong deep wing-beats with short periods of gliding. The white-bellied sea eagle (Haliaeetus leucogaster), also known as the white-breasted sea eagle, is a large diurnal bird of prey in the family Accipitridae. Originally described by Johann Friedrich Gmelin in 1788, it is closely related to Sanford's sea eagle of the Solomon Islands, and the two are considered a superspecies. A distinctive bird, the adult white-bellied sea eagle has a white head, breast, under-wing coverts and tail. The upper parts are grey and the black under-wing flight feathers contrast with the white coverts. The tail is short and wedge-shaped as in all Haliaeetus species. Like many raptors, the female is slightly larger than the male, and can measure up to 90 cm (35 in) long with a wingspan of up to 2.2 m (7.2 ft), and weigh 4.5 kg (9.9 lb). Immature birds have brown plumage, which is gradually replaced by white until the age of five or six years. The call is a loud goose-like honking. Resident from India and Sri Lanka through Southeast Asia to Australia on coasts and major waterways, the white-bellied sea eagle breeds and hunts near water, and fish form around half of its diet. Opportunistic, it consumes carrion and a wide variety of animals. Although rated as Least Concern globally, it has declined in parts of southeast Asia such as Thailand, and southeastern Australia. It is ranked as Threatened in Victoria and Vulnerable in South Australia and Tasmania. Human disturbance to its habitat is the main threat, both from direct human activity near nests which impacts on breeding success, and from removal of suitable trees for nesting. The white-bellied sea eagle is revered by indigenous people in many parts of Australia, and is the subject of various folk tales throughout its range. The white-bellied sea eagle has a white head, rump and underparts, and dark or slate-grey back and wings. In flight, the black flight feathers on the wings are easily seen when the bird is viewed from below. The large, hooked bill is a leaden blue-grey with a darker tip, and the irides are dark brown. The cere is also lead grey. The legs and feet are yellow or grey, with long black talons (claws). Unlike those of eagles of the genus Aquila, the legs are not feathered. The sexes are similar. Males are 66–80 cm (26–31 in) long and weigh 1.8–3 kg (4.0–6.6 lb). Females are slightly larger, at 80–90 cm (31–35 in) and 2.5–4.5 kg (5.5–9.9 lb). The wingspan ranges from 1.78 to 2.2 m (5.8 to 7.2 ft). A 2004 study on 37 birds from Australia and Papua New Guinea (3 °S to 50 °S) found that birds could be sexed reliably on size, and that birds from latitudes further south were larger than those from the north. There is no seasonal variation in plumage. The moulting pattern of the white-bellied sea eagle is poorly known. It appears to take longer than a year to complete, and can be interrupted and later resumed from the point of interruption.

Habitat:

Udawalawe National Park. The national park was created to provide a sanctuary for wild animals displaced by the construction of the Udawalawe Reservoir on the Walawe River, as well as to protect the catchment of the reservoir. The reserve covers 30,821 hectares (119.00 sq mi) of land area and was established on 30 June 1972. Udawalawe is an important habitat for water birds and Sri Lankan elephants. Udawalawe lies on the boundary of Sri Lanka's wet and dry zones. Plains dominate the topography, though there are also some mountainous areas. The Kalthota Range and Diyawini Falls are in the north of the park and the outcrops of Bambaragala and Reminikotha lie within it. The park has an annual rainfall of 1,500 millimetres (59 in), most of which falls during the months of October to January and March to May. The average annual temperature is about 27–28 °C (81–82 °F), while relative humidity varies from 70% to 83%. Well-drained reddish-brown soil is the predominant soil type, with poorly drained low humic grey soils found in the valley bottoms. Mainly alluvial soils form the beds of water courses. The habitat surrounding at the reservoir includes marshes, the Walawe river and its tributaries, forests and grasslands. Dead trees standing in the reservoir are visual reminders of the extent of forest cover before the construction of the Udawalawe Dam. Areas of open grassland are abundant as a result of former chena farming practices.