Delayed by cyclone, migratory birds begin to arrive in wetlands across state

With minimum temperatures across the state dipping even lower than 15 degrees Celsius, the condition is ideal for the arrival of such birds in the state in huge numbers, they added.

Arjan Basu Roy of Nature Mates Nature Club, an NGO that works for wildlife conservation and spreading awareness, said, “Generally, migratory birds start arriving in the state from mid-September. However, they arrive in flocks once the winter sets in. This year, the arrival of winter in West Bengal was delayed due to cyclone Michaung. Winter has finally set in. Therefore, we can expect migratory birds to fill the water bodies in droves by Christmas.”

According to him, so far about 90 to 100 species of migratory birds, including both aquatic and terrestrial birds, have arrived in the state but not in huge numbers.

“There are two types of migratory birds that come here. The first are trans-boundary migratory birds which are mostly trans-Himalayan species coming from Eurasian regions. The other are local migratory birds which come from the Himalayan region and other parts of the country. Another kind are the passage migrant birds. These birds stay here for a while before journeying to their destination country,” said Roy.

Most trans-boundary migratory birds found in West Bengal come from Eurasian regions such as Russia, China, Kazakhstan, Mongolia and surrounding areas. Some of them are: northern pintail, gadwall, ferruginous duck, common teal and garganey. Waders like curlew and the great knot are also spotted.

The local migratory birds spotted at different sanctuaries include whistling ducks, common moorhen, cotton pygmy goose and other water birds.

The majority of these migratory birds come from Eurasia and central Asia during the winter as water bodies in these regions freeze due to the cold and food becomes scarce.

They leave their natural habitats in northern areas during winter to relatively warmer areas in the south. Migratory birds are found in north Bengal wetlands like Gajoldoba, Gorumara; wetlands in Malda district and Murshidabad’s Farakka; Purbasthali in Purba Bardhaman district, Ballavpur in Paschim Medinipur district, sanctuaries in Purba Medinipur and Purulia districts and Sundarbans.

In and around Kolkata, such birds are sighted at Santragachi jheel in Howrah, Baruipur marshland, Rajarhat grassland, Nalban, Rabindra Sarobar and other water bodies. These birds return to their original habitat by early April. “Birds have started coming here but not in huge numbers. Over the next few days, they will come in droves. We cannot say the exact number of birds which have arrived. The exact number and species of birds arrived in the state are confirmed once the Asian Waterbird Census (AWC) is conducted. The census is conducted between mid-December to mid-February,” said Kanad Baidya, a member of Birdwatchers’ Society in West Bengal.

“The arrival of birds has started. It has been delayed due to late arrival of winter. In January, AWC will be conducted. We expect birds to come in large numbers by then,” said Sujan Chatterjee, conservationist and another member of the Birdwatchers’ Society.