White-bellied heron

The white-bellied heron (Ardea insignis) also known as the imperial heron or great white-bellied heron, is a large heron species living in the foothills of the eastern Himalayas in northeast India and Bhutan to northern Myanmar. It inhabits undisturbed rivers and wetlands. It has been listed as Critically Endangered on the IUCN Red List since 2007, because the global population is estimated at fewer than 250 mature individuals and threatened by habitat loss and human disturbance. It is mostly dark grey with a white throat and underparts.

The white-bellied heron has a uniform dark grey plumage, a whitish belly, and long silvery or whitish plumes on the rear crown and lower foreneck. In breeding plumage, it has a greyish-white nape plume and elongated grey breast feathers with white centers. The face is greenish grey and the 15.2–17.6 cm (6.0–6.9 in) long bill black, but greenish near the base and tip; the iris is yellow to ochre, and the legs and feet are dull grey. Juveniles are browner above and have a paler bill and paler legs. In flight, it has a uniform dark grey upperwing and white underwing covert feathers contrasting with dark grey flight feathers. The rump appears pale grey.

With a height of 127 cm (50 in), it is the second largest heron. A white-bellied heron killed by the upper Ayeyarwady River in 1903 had 61 cm (24 in) long wing bones, a wing spread of 100 cm (40 in) and a wingspan of 210 cm (84 in). Its mean weight is estimated at 3.2–3.4 kg (7.1–7.5 lb).