The population of dolphins in Chilika, India’s largest brackish water lake, and along the Odisha coast has doubled this year compared with last year.
The wildlife wing of the State Forest and Environment Department released the final data on the dolphin census conducted in January and February this year, indicating a spectacular growth in numbers.
Divided into 41 units, wildlife activists, academicians, Forest Department officials, NGO members, boat operators and researchers from the Bombay Natural History Society, Mumbai, participated in the estimation exercise.
The population estimation exercise for dolphins and other cetacean species covered almost the entire coast of Odisha.
Three species were recorded during the census, with 544 Irrawaddy, bottle-nose and humpback dolphins sighted this year, compared with 233 last year.
Wildlife activists are elated over the sizeable growth in the population of endangered Irrawaddy dolphins, which are mostly found in Chilika lake, jumping from 146 in 2020 to 162 this year. Apart from Chilika, 39 Irrawaddy dolphins were sighted in the Rajnagar mangrove division, though their number has come down from 60 in 2020.
The highest growth has been noticed in the case of humpback dolphins. Only two humpbacks were sighted in the Rajnagar mangrove in 2020. In 2021, however, this population grew astronomically to 281.
“In 2020, the weather conditions were really bad.This year, our teams came across some large groups of humpback dolphins near Ekakula and Habelikhati areas, close to the Gahirmatha Olive Ridley nesting ground,” said Bikash Das, Divisional Forest Officer, Rajanagar (Mangrove) Division.
“These humpback dolphins were not part of any riverine systems, so they cannot be identified as residential mammals. They were spotted travelling along the Odisha coast and the number is likely to fluctuate in the next census,” Mr. Das added.
The number of bottle-nose dolphins grew from 23 in 2020 to 54 this year.
“The rise in the Irrawaddy [dolphin] population in Chilika can be attributed to the eviction of illegal fish enclosures. After thousands of hectares of Chilika water were made encroachment-free, Irrawaddy dolphins found unobstructed area for movement. Moreover, due to the COVID-19 lockdown last year, there were comparatively fewer tourist boats on Chilika lake, which made it conducive for dolphins to move from one part [of the lake] to another,” said Susanta Nanda, Chief Executive of Chilika Development Authority.
