Dolphins Population Dwindles in Gahirmatha Marine Sanctuary in Odisha

Feb 25,2020

Dolphin population is fast dwindling in the water bodies of Gahiramatha Marine Sanctuary and its nearby areas within Bhitarkanika National Park here.

Pivotal Points:

• Odisha’s recent annual census of dolphins shows their population declining from 469 in 2018 to 259 this year.
• The census was carried out by the state’s forest and environment department on January 19 2020.
•  The census report was released on February 14.2020.
• The census covered important aquatic ecosystems in the state including the Chilika lake, India’s largest brackish water lagoon, spread over the Puri, Khurda and Ganjam districts, the Gahirmatha Marine Sanctuary and its nearby areas within the Bhitarkanika National Park in Kendrapara district, Balasore district and the mouth of the Rushukulya river in Ganjam district.
• According to the 2019 dolphin census report  Gahirmatha is the home of the state’s largest dolphin population, having 126 animals. 
• After Gahirmatha, Chilika had the next largest population at 113, followed by the Rushukulya river in Ganjam district, with 15 dolphins and finally, Balasore, with 5 individuals.
• The dolphin species sighted during the state-wide census included the Irrawaddy, the Bottle Nose and the Humpback. The sighting of dolphins depended on the weather condition of the day the census was carried out. 

About Irrawady Dolphins:

• The Irrawaddy dolphin is not a true river dolphin, but an oceanic one that lives in brackish water near coasts, river mouths and in estuaries.
• Across Odisha, 130 Irrawaddy dolphins were sighted on January 19, 2019.
• Out of these, 113 were sighted in Chilika, where 162 animals had been sighted last year and 123 in 2017. In Gahirmatha, 14 Irrawaddy dolphins were sighted. In Balasore district, 3 animals were sighted.

About Bottle Nose Dolphins:

• A total of 16 Bottle Nose dolphins were seen in Odisha. Out of these, 2 were sighted in Balasore and 14 in Gahirmatha.

About Humpback Whale

• The third species, the Humpback, totalled around 113 animals of which 98 were sighted in Gahirmatha and 15 in Ganjam.

Conservation Status:

• Dolphins have been included in Schedule I of the Indian Wild Life (Protection) Act 1972, in Appendix I of the Convention on International Trade in Endangered Species (CITES), in Appendix II of the Convention on Migratory Species (CMS) and categorised as ‘Endangered’ on the
• International Union for the Conservation of Nature’s (IUCN) Red List Status: Endangered.

Reason for Dwindling Numbers:

• The reduction in the number of dolphins compared to last year could be due to the migration of species from the Chilika lake and other water bodies to the deep sea.
• Climate change and bad weather may be also the reasons for the dolphins to migrate towards the deep sea. 
•  According to forest officials, death may not the reason behind the decline in numbers. 
• Forest officials conduct dolphin censuses in the sea at a distance of only 10 kilometres from the coast as it is not possible for them to count dolphins in the deep sea.