Bangladesh to create sanctuary for Irrawaddy Dolphins

Bangladesh Wildlife authorities are declaring three areas in the Sundarbans mangrove forest as dolphin sanctuaries to protect an endangered species of freshwater dolphins from extinction.

The forestry department took the decision after studies found three areas in the UNESCO-listed Sundarbans mangrove forest, which straddles Bangladesh and India, were home to large populations of Irrawaddy and Ganges river dolphins.

“We have decided to declare river channels at Dhangmari, Chandpai and Dudhmukhi areas in the eastern Sundarbans as dolphin sanctuaries. This will help in promoting eco-tourism as well,” Tapan Kumar Dey, senior wildlife conservation official at the forest department, said.

The dolphins, known as Irrawaddy Dolphins or locally as Sushuk, live in the southern mangrove forest, the main habitat of the endangered mammal.

Began in 2002, around 6,000 river dolphins live in the area stretching from the Irrawaddy River to southern region of Bangladesh. There are only 100 Irrawaddy dolphins in the world living outside this area, near Southeast Asia’s Mekong delta.

According to conservationists, this intricate network of rivers- Ganges, Brahmaputra and Meghna is currently the only place in the world where both the Ganges River and Irrawaddy dolphins are found. Ganges river dolphins are found largely in the northern regions, and the Irrawaddy dolphins in the south.

The Bangladesh ministry of the environment will shortly issue official notification on the establishment of the sanctuaries and the waterways in these areas will be ‘clearly demarcated’ with signs to prevent local fishermen straying into the restricted areas. Although the animals are not targeted directly by fishermen, they often get entangled in fishing nets and die in dozens every year. They are also threatened by rising salinity and pollution.

What are Irrawaddy Dolphins?

Irrawaddy dolphins are found in the Indo-Pacific, from northeastern Australia in the south, north to the Philippines, and west to northeastern India.

The Irrawaddy dolphin is identified by a bulging forehead, a short beak, and 12-19 teeth on each side of each jaw. The pectoral fin is broadly triangular. There is a small dorsal fin, on the posterior end of the back.

When diving, this dolphin breathes at intervals of 70-150 seconds; the head appears first and then disappears, and then the back emerges, but the tail is rarely seen. Head and body length is 180-275 cm. Irrawaddy dolphins are slaty blue to slaty gray throughout, with the under parts slightly paler.

Irrawaddy Dolphins – Unexploited but vulnerable

Although the Irrawaddy dolphin is not directly exploited, it is exposed to incidental mortality in fisheries, the principal cause of depletion. Habitat degradation due to development of dams, deforestation and mining also continue to undermine the species to a lesser extent.

Conservation of this enigmatic mammal, which lives in both river and marine environments, will depend on devising and implementing sound solutions for replacing harmful fishing practices and halting or mitigating the impacts of habitat loss on Bangladesh ecology.