White-bellied Heron and Hydropower Threat in Arunachal Pradesh

White-bellied Heron and Hydropower Threat in Arunachal Pradesh

#GS-3 #Environment #Wildlife #Biodiversity #Current Events #National

Why in News

  • A proposed 1,200 MW hydropower project on the Lohit River in Arunachal Pradesh threatens the survival of the White-bellied Heron.
  • This species is currently recognized as one of the rarest and most threatened birds in the world.

About the White-bellied Heron

  • The White-bellied Heron (Ardea insignis) is also known as the imperial heron or great white-bellied heron.
  • It belongs to the family Ardeidae and is the 2nd-largest heron in the world.
  • It relies strictly on fast-flowing eastern Himalayan rivers surrounded by undisturbed, mature riparian forests.
  • The bird feeds mainly on fish in shallow rapids up to elevations of 1,500 m above sea level.

Physical and Behavioural Traits

  • It has a flexible neck and a sharp serrated bill to catch fish in deep water.
  • Short legs and a compact body help it stay stable in swift currents, while long toes grip slippery rocks.
  • Standing up to 4 feet tall, it waits completely still and strikes rapidly when fish swim close.
  • It lives a solitary life, makes deep croaking sounds at dawn and dusk, and nests in tall trees.

Conservation Status and Distribution

  • The IUCN Red List classifies this bird as Critically Endangered, and India gives it top legal protection under Schedule-I of the Wildlife Protection Act, 1972.
  • Fewer than 60 individuals survive in the wild across Bhutan, India, Myanmar, China, and Bangladesh.
  • Bhutan holds ~45% of the global population with 3-5 active breeding pairs, serving as its final stronghold.
  • The species is already extinct in Nepal and is likely extinct in Bangladesh.
  • India shelters only 6-9 individuals, primarily in Arunachal Pradesh across the Noa-Dehing River, Lahm River, and Lohit River.
  • The Lahm River basin contains 70% of India's population, while Walong Cantonment near the project site serves as a breeding ground.

Ecological Significance and Threats

  • As a bio-indicator for Himalayan freshwater ecosystems, its presence shows good water quality and healthy fish stocks.
  • Hydropower dams disrupt river flows, fragment habitats, and alter water clarity, directly impacting the bird's survival.
  • Habitat loss, hunting, human disturbance, and a very small gene pool further increase its risk of extinction.

Way Forward

  • India needs to establish dedicated conservation breeding facilities to protect the remaining population.
  • India can adapt successful strategies from Bhutan, which operates the world's first captive facility for hatching and rearing this endangered species.