Climate change may push Assam's state bird to extinction, study warns

The study stated that 436.61 square kilometers of highly potential habitat would be lost by 2070

Assam's state bird, the white winged wood duck, locally called as Deo Hanh or divine bird could be pushed to extinction due to climate change impact and other worsening anthropogenic pressures in the Indian Eastern Himalayan (IEH) region, a study conducted by a team of researchers have warned.

The IEH region, particularly Assam, Arunachal Pradesh, and Manipur, houses more than half (450) of the 800 global population of white winged wood duck, declared an endangered species by the International Union for Conservation of Nature (IUCN) in 1994. The bird species is found in India and some other nations sharing a border with the Northeast. It was declared as Assam's state bird in 2003.

The study on the impacts of climate change on Assam's state bird has stated that 436.61 square kilometers of highly potential habitat would be lost by 2070.

"Tropical forests support the population of the white winged wood duck. It is projected that climate change will have a significant impact on tropical forest ecosystems around the globe. Under the influence of global climate change, a major portion of the natural habitat of the WWWD is likely to be lost by 2050 and 2070," said the study.

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The report was recently published in the Journal of Nature Conservation. The research team included Jyotish Ranjan Deka and Syed Ainul Hussain of Wildlife Institute of India, Dehradun, Animesh Hazarika of Assam University, Silchar, Abhijit Boruah, Jyoti Prasad Das and Rubul Tanti of Aaranyak, a biodiversity conservation group in Assam.

The study said that area with an annual average temperature range of 22 degrees Celsius − 30 degrees Celsius and annual precipitation of 1,000–1,200 mm has the highest probability of occurrence of the bird species. But the potential distribution would likely decline in every state due to climate change, except in Meghalaya.

Changes in the annual temperature range, precipitation in the wettest month (June to September), and precipitation decrease in the warmest quarter (October to December) will be the key bioclimatic variables to lead to a substantial loss of high potential habitats, said the report.

The potential of areas located at the Bhutan and Assam border would increase for supporting the white winged wood duck as this species’ requires the average annual precipitation of about 1,000–1,200 mm, it said.

The study further said that anthropogenic threats such as habitat loss, forest fragmentation, habitat degradation, water pollution and drying up of water bodies due to climate change have reduced the population of the bird species in their natural habitats. Hunting and collecting eggs for food have further threatened their existence. In the tropical forests of Assam, a decline in the population of white winged wood duck has been observed mainly because of the destruction of forest habitats and the clearing of forests near water bodies," it said.

Another study conducted by Wildlife Trust of India between 2018-2020 had stated that the white winged wood duck was facing the threat of extinction due to widespread loss of forest habitat and hunting across its distribution range.