Pleased with more migratory birds flocking to the park, forest officials attributed the 'favourable environment at the park' for the rise in numbers. However, experts countered the claims, saying lower air pollution levels as compared to last year may have led to the spike in numbers.

While 25,000 migratory birds visited the park last season (2015-16), this season, the number has crossed the 30,000 mark, official figures reveal. Also, an increase has been reported in the number of species of migratory birds visiting the park. While as many as 74 species have visited the park so far this year, 69 species visited the park last year.

"We are glad that more birds have been visiting the park. Many rare species of resident birds have also been spotted this year. It definitely shows that environment in and around the park is becoming more favourable for the birds," said district forest officer (DFO) Shyam Sunder.

Over 300 Gadwall, common dabbling ducks, that come all the way from Siberia, six-seven flocks of common teal and over 15 flocks of Urasian Spoonbill, known for spoon-like shape of its beak, were spotted in the park.

According to bird watchers, however, lower air pollution levels contributed to the rise in the footfall.

"I have been visiting the park for the last two months. Definitely, there are more birds visiting the park than last year. However, the reason is not just the proper maintenance of the park, but also that levels of air pollution this winter remained lower than that of last year," said Vidhu Singh, an avid bird watcher.

A city-based ornithologist, Dr Karuna Singh, further mentioned, "Increase in the air pollution leads to many problems among birds, including choking and dizziness. Last year, birds moved to other wetlands as the city was very polluted."