Habitat specialists — particularly birds of grasslands and other open habitats like bustards and coursers, wetlands, and woodlands — are declining rapidly while in terms of diet, carnivores, insectivores, and granivores are on the wane more rapidly than omnivores or fruit-and-nectar eaters.
Also, migratory bird species appear to be under greater threat than non-migrants while species endemic to the Western Ghats–Sri Lanka region are faring worse than others. These are some of the disturbing findings revealed in a recently released report ‘State of India’s birds.’
Overall, of the 338 bird species studied in India for changes in numbers over the last 30 years, 60 per cent have experienced a decline, as per the data based on observation of about 30,000 birdwatchers across the country.
The scenario is not encouraging in the short-term as well, with the report stating that 40 per cent (142) of the 359 species evaluated for change over the last seven years have declined. The assessments rely on three indices: two are related to the change in abundance -- long-term trend (change over 30 years) and current annual trend (change over the past seven years) -- and the third is a measure of distribution range size within India.
Of the total of 942 species evaluated, long-term trends could be determined for 338 species. Of these, 204 species have declined, 98 are stable and 36 have increased, says the report published by a group of 13 government and non-government institutions, including the Bombay Natural History Society (BNHS), Wildlife Institute of India (WII), and Zoological Survey of India (ZSI).
Current annual trends could be determined for 359 species, of which 142 have declined (64 rapidly), 189 are stable, and 28 have increased. The report classifies 178 species, including Northern Shoveler, Northern Pintail, Common Teal, Tufted Duck, Greater Flamingo, Sarus Crane, Indian Courser and Andaman Serpent Eagle, as "high conservation priority".