More than 5,600 birds were recorded during a count conducted at Santragachhi Jheel on Saturday.

The number of birds recorded at the water body this year is higher than the count over the past five years, said birdwatcher Prosenjit Dawn, who has been part of the census for more than 10 years.

The counting procedure is tedious and requires an experienced set of eyes.

Dawn said seven men and women spread around the water body in teams to count birds. The volunteers carried telescopes.

“It is quite tedious and we have to use telescopes as many birds hide in the water hyacinths and are difficult to spot. Drones cannot be used as birds fly away,” said Dawn.

Four Northern Pintails, trans-Himalayan migrants, were spotted on Sunday.

Only one was spotted on Saturday.

Northern Pintails fly from Siberia, Mongolia and northern China to spend the winter months in temperate zones.

This year, around 25 Gadwalls and one Ferruginous Pochard have been spotted at the jheel.

Gadwalls and Ferruginous Pochards breed in central Asia, China and Mongolia and fly thousands of miles to the subcontinent to escape the harsh winter there.

The Ferruginous Pochard, also called Ferruginous Duck, is listed as “near threatened” by the International Union for the Conservation of Nature (IUCN).

A Black Winged Stilt, another trans-Himalayan migrant that had never been known to have been sighted at Santragachhi, was seen at the water body in the first week of December, said Dawn. This year's count revealed that the overwhelming majority of birds are Lesser Whistling Ducks, which are found around water bodies in Bengal through the year but in far smaller numbers. The ducks numbered 5,536.

Among other birds, 25 Gadwalls, a couple of Bronze Winged Jacanas and three Barn Swallows were recorded.

V.K Yadav, the chief wildlife warden, said bird counts were on at every place where migratory birds roost.