The annual three-day waterfowl estimation began on Tuesday at Pong Dam, one of the largest man-made wetlands in the foothills of the Himalayas, in the picturesque Kangra Valley of Himachal Pradesh, a wildlife official said.
An estimation of around 40,000 bar-headed geese, the world's highest-altitude migrant, is expected.
More than 150 bird watchers and staff of the state wildlife department are participating in the dawn-to-dusk exercise, Assistant Conservator of Forests (Pong wetlands) D.S. Dadwal, who is associated with the census, told IANS.
He said ornithologists of the Bombay Natural History Society (BNHS), the Wildlife Institute of India and the Zoological Survey of India are also participating and they would count both local and migratory waterfowl species (birds that depend on water bodies for roosting and feeding).
With the onset of winter, thousands of migratory birds from central and northern Asia start arriving for their annual sojourn in the Pong Dam reservoir, 250 km from state capital Shimla.
"As per our estimates, the largest influx this time again is of the bar-headed geese. Their number would be around 40,000," he said.
More From This Section
The other prominent species are the coot, common pochard, red-crested pochard, great cormorant, gadwall, northern pintail, river tern and the spotbill duck.
Another wildlife official said the influx of birds could be seen in the Nagrota Suriyan, Sathana, Sansarpur Terrace and Rancer Island areas.
The Pong wetlands are also home to many native birds like the red jungle fowl, large Indian parakeet, Indian cuckoo, bank myna, wood shrike, yellow-eyed babbler, black ibis, paradise flycatcher, crested lark and the crested bunting.
Over 130,000 birds of 93 species had been spotted last year in the Pong wetlands, among them the greater white-fronted geese, pied avocet, osprey, Sarus crane, black bellied tern, common shelduck, buff bellied pipit, water pipit and little gull - all of which are rare in other Indian wetlands.
The bar-headed goose is a regular and prominent winter visitor in the Pong Dam wetlands, spread over 307 sq km.
A staggering 71,800 bar-headed geese were recorded last year, a new mark so far.
The gregarious bar-headed goose, which start arriving in October and stay till March-end, feeds at night in grasslands on riverbanks and breeds in high-altitude lakes in Central Asia, was also in Tibet and Ladakh.
Listed under Schedule IV of the Wildlife Protection Act, 1972, the global population of the bar-headed geese is believed to be around 130,000, wildlife experts say.
The Pong wetlands occupy an area of at least 18,000 hectares and extend up to 30,000 hectares at the peak monsoon season. An area of about 20,000 hectares within a radius of five kilometres has been notified as a buffer zone dedicated to wildlife.
A total of 423 species of birds, 18 species of snakes, 90 species of butterflies, 24 species of mammals, 27 species of fish have so far been recorded in Pong Dam wildlife sanctuary.
(Vishal Gulati can be contacted at vishal.g@ians.in)