BHUBANESWAR: The latest dolphin survey has found the endangered Irrawaddy dolphins, the flagship species of Chilika lagoon, in multiple habitats, pointing at the possibility that the species may be colonising areas beyond its known range.
The marine species inhabiting the Chilika lake is protected under the Wildlife (Protection) Act 1972, CITES (Appendix-l), and IUCN Red List. Over the years, the 1,100 sq km brackish water lagoon has evolved as a safer home for these dolphins whose distribution range is now mostly limited to Asia - from Chilika to Indonesia.
The Rajnagar Mangrove wildlife division too holds a very smaller population of this aquatic mammal. However, conservationists have also found that it has started inhabiting coastal range of Berhampur forest division as well as Puri and Balasore wildlife divisions.
The annual population estimation of dolphins and cetaceans 2025-26 carried out last month pegged the total number of Irrawaddy dolphins in the state at 208. Of this, 159 have been spotted in Chilika while another nine have been spotted in Rajnagar.
However, beyond these two ranges, around 15 Irrawaddy dolphins were sighted in Balasore wildlife division, while 13 were found in the marine waters of Berhampur forest division. Puri wildlife division too reported 12 Irrawaddy dolphins during this year’s enumeration.
RCCF Berhampur circle Vishwanath Neelannavar said the Irrawaddy dolphins have been sighted in Berhampur division for the second year in a row, while sources said the mammals were sighted in Puri for the first time in three years. The division had recorded four Irrawaddy dolphins in 2023.
PCCF (wildlife) Prem Kumar Jha said dolphins beyond Chilika is a good sign. He, however, said it is difficult to conclude if they are colonising new areas in absence of a recurring sequence.
Jha said the sighting of less number of Irrawaddys in mangrove wildlife division and their higher count in other divisions this year signals towards a migration. “We will institute a study to find if any such migration is taking place and determine the areas these dolphins are colonising beyond Chilika and Rajnagar,” Jha told TNIE.
Currently, the population of Irrawaddy has remained almost stable in Odisha coast including Chilika in the last five years. In 2020-21 and 2021-2022, the population of the species had been pegged at 209 and 208 respectively.
Former PCCF and wetland specialist Ajit Patnaik said Irrawaddy dolphin has a unique adaptation mechanism and the species can survive in both sea water and brackish water and to some extent in fresh water.
He suggested that a transect survey be introduced for a robust enumeration of the Irrawaddy dolphins.