Freshwater dolphins make comeback in Nepal

A pod of dolphins at the confluence of the Mohana and Karnali Rivers recently. The endangered mammals swim upstream from India to breed in Nepal every monsoon.

It is the annual monsoon season, and despite the rains this would be the time of year when tourists flocked to the tributaries of the Karnali River in Nepal for dolphin watching.

When the rivers are in spate is when the endangered Gangetic Freshwater Dolphin swim upstream from India to the mighty Karnali, Nepal’s longest river, to find mates on the still backwaters of the oxbow lakes.

But this year, due to the COVID-19 lockdown there is no one here to watch the nearly-blind aquatic mammals as they surface to exhale noisily through the blowholes on top of their heads.

Swimming upstream in the strong current is hard enough, but navigating through memory and echo-location could be even more difficult for the only cetacean species found in Nepal. But they follow mind maps that they have inherited from ancestors to travel to the same spot every year to breed and rear calves.

“When water levels begin to rise, they can be easily spotted,” says Bhoj Raj Dhungana of the Dolphin Aquatic and Biodiversity Conservation Nepal. “They swim all the way from the Ganges to breed and rear their young in safer, more shallow waters in Nepal.”

Dhungana says that although only a mother dolphin and her calf had been sighted till mid-June, in the past month five juveniles and 10 adults have been seen in the waters.

Locally referred to as ‘Susu’ after the sound they make while surfacing to breathe, these playful mammals are mostly found along the Karnali’s confluence with rivulets like the Mohana, Pathariya, and Kada in Kailali. As the monsoon tapers off, they swim back downstream into India.

After being red-listed as an endangered species by both the International Union for Conservation of Nature (IUCN) and the World Wildlife Fund (WWF), Gangetic Freshwater Dolphins are now actively protected in Nepal and India. Local conservation organisations in Tikapur and Bhajani municipalities whose communities benefit from dolphin tourism are also involved.

River dolphins are known to be accurate indicators of a river’s health. If their numbers decline, as they have been for decades, it means the rivers are polluted, there is overfishing, they are entangled in fishing nets, or new dams are preventing their migration for breeding.

Over the years, the total number of Gangetic dolphins have decreased from 5,000 to less than 2,500. They used to be present in all of Nepal’s big rivers like the Kosi, Gandaki and Karnali. But except for the Karnali the other two are both dammed at the Indian border for irrigation and flood control, and the numbers in Nepal have dramatically declined.

“Although Gangetic dolphins visit our rivers annually in the monsoon, increased pollution of the rivers and the poaching for food has seriously depleted their numbers,” says dolphin conservationist Vijay Raj Shrestha, who noticed that the dolphins appeared earlier than usual this year possibly because of heavy pre-monsoon rains and the lack of disturbance due to the COVID-19 lockdown.

The government is now trying to declare the confluence of the Mohana and Pathriya as a Dolphin Conservation Area, ban the use of fishing nets and prevent plastic garbage  dumping and use of fishing nets in the rivers.

Wildlife enthusiasts from all over the world used to flock to Kailali to watch dolphins, contributing to the local economy and spreading awareness among local people about the importance of conserving the rare mammals. However, visitors had to rough it because of the lack of standard hotels and difficult access through dirt tracks.

Freshwater dolphins are found in South America and Asia, and regarded as some of the oldest creatures on earth. They have lost their sense of sight because they live in such murky waters, instead they use ultrasonic clicks to navigate and find prey. They travel in pods with their calves.

The World Wildlife Fund (WWF) is helping Nepal and India to upgrade conservation efforts and to spread awareness about river pollution. In Nepal, WWF has supported a dolphin census and monitored their population, while also adivising the national and local governments about their conservation.