A full-grown Russell's viper (Daboia russelii), trapped in a fishing net near the Damodar in Howrah's Bagnan, was freed and released in a suitable habitat on Sunday.

Russell’s vipers — called Chandrobora in Bengali for lunar marks all over its body — are among the four most poisonous groups of snakes, the other three being Indian cobra, saw-scaled viper and Indian common krait.

Russell's viper accounts for the highest number of snakebites in India.

The snake was first spotted by villagers who alerted Chitrak Pramanik, a local wildlife conservationist and a trained snake catcher.

Pramanik and Sumonta Das, both members of a platform that works for wildlife conservation in Howrah, reached the spot, near Gopalpur village on the banks of the Damodar in Bagnan, around 60km from the heart of Calcutta, around 1.30pm on Sunday.

As Pramanik held the snake with a tong, Das used a stick and scissors to cut the net. They maintained a safe distance from the reptile all along the operation.

"The snake was first freed from the net and then carried into a bag. We later released it into a suitable habitat," said Pramanik, who became a certified snake rescuer in 2022, after five years of training.

"The villagers must be thanked for informing us in time. The scare that the sight of a snake causes often prompts people to beat it to death. But snakes play a very important role in maintaining the ecological balance," said Pramanik.

Pramanik's group, which goes by the name of Howrah Jela Joutho Paribesh Mancha, conducts regular awareness campaigns on snakes and other conflict-prone animals in the district.

On October 3, Pramanik and his colleagues had rescued two baby snakes, one a monocled cobra (Naja kaouthia) and the other a common krait (Bungarus caeruleus), from a village in Bagnan.