Critically endangered white-bellied heron records successful breeding in Arunachal

[ Dr Ngilyang Tam ]

The white-bellied heron (Ardea insignis) is a critically endangered species and is the second largest species of heron, standing approximately 127 cms tall and characterised by a large blackish bill measuring 15-18 cms in length.

Globally, the white-bellied heron has a small population of a few dozen individuals, occurring mainly on the southern side of the eastern Himalayas as a resident species in the landscape of central Bhutan, India and Myanmar. One of the biggest challenges is that the species occurs at low density, and the overall population is regarded as insufficient for future long-term survival of the species.

Considering its rarity, low population density, and it being most threatened, the bird is protected under Schedule I of the Wildlife (Protection) Act, 1972 (Amendment, 2022).

In India, the white-bellied heron occurs in Assam and Arunachal Pradesh. India may be host to the largest population of the white-bellied heron, but the population surveys have been very limited. The Namdapha National Park (NNP) in Arunachal has been noted as a stronghold of the species, where sightings of the species have been recorded since 2014. Further, only Arunachal holds a breeding population in India, particularly in the NNP, which has the highest population of white-bellied heron, as per available literature.

Due to lack of white-bellied heron-specific surveys in the known and unknown river basins in Arunachal, there has been no report of the white-bellied herons breeding record.

However, on 10 May this year, during monitoring of the elusive bird, a team from Gangtok (Sikkim)-based Ashoka Trust for Research in Ecology & Environment (ATREE), observed two nestlings covered with pin feathers. This is probably the first successful recorded white-bellied breeding in India.

On observation, the researchers could see two juveniles which had developed distinct feathers in the neck and the belly. The documentation of successful breeding of white-bellied heron in the NNP underscores the need for urgent conservation interventions. It is a species that is known to be very rare, and is reported to be extirpated from Sikkim, Bihar, West Bengal, Nepal and Bangladesh due to habitat destruction and anthropogenic activities,mainly related to development. Thus, there is a need for intensive surveys to identify further nests and ensure that the birds are not disturbed during the nesting season.

The white-bellied heron’s nesting records had been previously recorded in the NNP in 2014, and in Walong in Anjaw district in 2021. It was recorded in 2019 also in the Kamlang Wildlife Sanctuary at the confluence of the Tawai and the Lahm River, through camera trapping and direct sighting. However, there had been no successful breeding record documented in India, until now. This could be due to the lack of prioritising conservation effort for the species. Therefore, a state-level conservation action plan for the species is essential for effective conservation of the species and its habitats, reducing threats that endanger the survival of the species. This is especially essential as Arunachal has the potential to hold the largest population of this rare and critically endangered species. (The writer is Chief Wildlife Warden, Arunachal Pradesh.)