Local environmentalists say so.

Durga Sagor is a famous sanctuary for guest birds coming from Sibera and Europe to escape chilling cold.

In earlier years, the birds usually started flying into the spot from September and stayed till March.

But this year, no guest bird is still seen there.

Change in the environment and sound pollution is the main cause of absence of guest birds there this year, local environmentalists said.

Noise of the nearby airport, busy highway, mike of mosques create sound pollution in the area regularly.

Food of the birds is also becoming scarce due to increased use of pesticides and chemical fertiliser in agricultural lands.

Lack of awareness among people about preservation of guest bird sanctuaries could be another cause of the absence of migratory birds this year, they said.

Officials have also not taken any step in this regard, they said.

Nature-loving people and tourists are also gradually loosing attraction of the historic Durga Sagor as the bird sanctuary has now changed into a den of extortionists. No body feels safe here due to absence of security men, especially in early morning and late afternoon.