KOLKATA: The Mamata Banerjee government has submitted a Dolphin Action Plan for the state to the Centre, proposing to have a dolphin census done in the Ganga and conduct an awareness campaign to prevent the endangered species, which was declared the National Aquatic Animal in 2010, from going into extinction.The state urban development department has written to the Centre with the proposal prepared by the state forest department under the ‘ National Mission for Clean Ganga ’. “The scheme proposes to conduct a dolphin census in the Ganga in West Bengal and conduct awareness programmes as part of the action plan,” said urban development secretary Debashis Sen.The number of dolphins has been dwindling alarmingly due to several factors, including river pollution. Only recently, the stretch of Ganga flowing within the state up to Sagar was included in Prime Minister Narendra Modi’s clean-Ganga mission.According to approximate estimates drawn from World Wide Fund for Nature (WWF) surveys, there are roughly 150 dolphins still living in the 34km stretch of Ganga from Farakka to Sagar. Experts feel that if not looked into immediately, the numbers will go down even further as their habitat is getting increasingly hazardous for dolphins. According to rough estimates, there are around 2,000 dolphins left in the entire Ganga, said experts.Dolphins are an endangered species, especially in the Ganga. Dolphins do not have eyes and find their way in the water through echolocation. If they get entangled in fishing nets, they can’t follow the echolocation and die soon as they need to come to the water surface every five to seven minutes for air. Barrages also pose a big threat as their natural environment becomes fragmented. Pollution in the Ganga is also a big problem for these marine mammals. Dolphin shows have already been banned in India.Sangita Mitra, one of the coordinators of the WWF who is supervising the dolphin project, said they have been working on the project since 2011. “We mainly check on the habitat of dolphins to see how far it is suitable for living,” she said.River expert Kalyan Rudra, who is also now chairman of the West Bengal Pollution Control Board , said preservation of dolphins is extremely important and an action plan is needed urgently for this purpose. He said the alarming drop in the number of dolphins in the Ganga is a “biological indicator of the pollution load in the river”.