White-bellied Heron

The White-bellied Heron, also known as the Imperial Heron or Great White-bellied Heron, is a majestic bird species that graces the eastern Himalayan foothills. With its impressive stature, it stands as the second-largest heron, exhibiting a predominantly dark grey plumage contrasted by a white throat and underparts. The heron's regal presence is further accentuated by long, silvery or whitish plumes that adorn the rear crown and lower foreneck.

Identification Tips

To identify this heron, look for its uniform dark grey upperparts and white underwing coverts, which starkly contrast with the dark grey flight feathers when in flight. The rump appears pale grey, and the bird's face is greenish-grey. Its bill, measuring between 15.2 and 17.6 cm, is black with greenish hues near the base and tip. The legs and feet are a dull grey, and the iris ranges from yellow to ochre. Juveniles can be distinguished by their browner upperparts and paler bill and legs.

Habitat

The White-bellied Heron favors the undisturbed rivers and wetlands nestled within the tropical and subtropical forests of the eastern Himalayas. It is particularly drawn to the low elevation riparian environments below 1,700 meters, where it can be found in the Sankosh River basin and its tributaries.

Distribution

This heron's range extends from northeast India and Bhutan to northern Myanmar. Notable refuges and breeding sites include Bhutan's Sankosh and Mangdechhu river basins, Kaziranga National Park in Assam, Pobitora Wildlife Sanctuary, and Namdapha National Park in Arunachal Pradesh. Sightings have also been reported along streams in the Hkakabo Razi landscape of northern Myanmar.

Behaviour

The White-bellied Heron exhibits a deep croak when disturbed and is known to call during the early morning and late night hours, particularly before sunrise. It roosts for extended periods during the day on various substrates, such as sandy patches, rocks, logs, and trees. At night, it adopts a sleeping posture with its head pressed against its breast. Adults typically roost alone, while juveniles may roost in pairs.

Song & Calls

The heron's call is a distinctive deep croak, described as "ock ock ock ock urrrrrr," which resonates most frequently before dawn and occasionally late at night.

Breeding

Breeding occurs in the Sankosh and Mangdechhu river basins, with nests constructed in trees like chir pine, champak, and bayur at elevations ranging from 400 to 1,430 meters.

Diet and Feeding

The diet of the White-bellied Heron consists primarily of Schizothorax carps throughout the year, supplemented by brown trout in spring and Garra fish species in summer. It prefers foraging in shallow river sections, ponds, pools, and island edges.

Conservation status

The White-bellied Heron is classified as Critically Endangered, with a global population estimated at fewer than 300 mature individuals. It faces threats from habitat loss, human disturbance, and habitat degradation due to agricultural expansion, settlement growth, resource harvesting, and poaching. Conservation efforts include legal protection in India and Myanmar, and the successful captive hatching and release of a heron in Bhutan's Punakha District.