The Himalayan forest thrush (scientific name Zoothera salimalii) is the fourth bird species to be discovered in India since 1947.
It is the first Indian bird named after late Salim Ali, who was closely associated with the Bombay Natural History Society-India, the BNHS statement said. Sálim Ali (November 12, 1896 – June 20, 1987) is also referred to as the ‘Birdman of India’.
Researchers Per Alstrom and Shashank Dalvi first discovered the species in May-June 2009 while studying birds at high elevations in western Arunachal Pradesh.
It was found that instead of a single species – plain-backed thrush (Zoothera mollissima) – as believed till now, there existed two different species in the eastern Himalayas.
The Himalayan forest thrush was overlooked till now due to its close similarity in appearance to the plain-based thrush, renamed now as alpine thrush.
New bird species are rarely discovered nowadays when most natural habitats are shrinking, it said. Since 2000, an average of five new species have been discovered globally every year, mostly in South America.
“It’s a remarkable discovery and shows how much more we have to do in the field of ornithology in India. It also proves that north-eastern India is a treasure trove of biodiversity that needs protection,” said senior scientific adviser and former BNHS director Asad Rahmani.
Studies of specimens stored in 15 museums across seven countries revealed there were differences in plumage and structure of the Himalayan forest thrush and the alpine thrush.
It was found that the Himalayan forest thrush breeding in coniferous and mixed forests of eastern Himalayas was not classified separately till now.
Scientists found that Himalayan forest thrush found in forests had a rather musical call, whereas alpine thrush found in the same region on bare rocky habitats above the treeline had a much harsher, scratchier and unmusical call.
Further analyses of plumage, structure, call, DNA and ecology throughout the range revealed the presence of a third species – Sichuan forest thrush – in central China, the BNHS said. It has an even more musical call than that of the Himalayan forest thrush.
This third species, about which information was already known, was earlier treated as a sub-species of the plain-backed/alpine thrush.
A fourth species from China remains unnamed. Future field studies are required to confirm it, the statement added.