Pakistan’s wildlife authorities and the World Wildlife Fund (WWF) are combing the Indus River to assess the population, behavioural changes and other relevant data of one of the most ‘docile, rare and shy’ mammals, the Indus Blind Dolphin.
At the time of the first survey in 2001, the dolphins, which are endemic to Pakistan and already listed by the International Union for Conservation of Nature (IUCN) as a ‘most threatened’ species, numbered only 1,100.
These dolphins do not have a crystalline eye lens and so are blind. They navigate underwater entirely by a sophisticated ‘echo-location system’.
These mammals swim with only one side underwater, and one flipper trailing in the muddy riverbed. The physical touch gives them important information about their surroundings and helps them find food.
‘Our conservation efforts have definitely yielded some positive results as we have managed to control further decline in its population,’ said Richard Garstang, a Pakistan-based WWF dolphin conservation manager.
Around 14 volunteers, professional biologists and scientists are taking part in the second survey of a 1,500 km length of meandering Indus in North-western Punjab province, downstream to Sukkur Barrage in southern Sindh province.
‘So far the results have been very encouraging as we have spotted some baby dolphins, which means they are still thriving,’ said biologist Uzma Khan.
The dolphins, whose local name is Bhulan, thrived in the muddy waters of the Indus until the 1930s when the British rulers built a number of barrages to store water for irrigation of agricultural lands.
This split the dolphin’s population into small groups, degraded their habitat and impeded migration. By the 1970s, the mammal’s concentration was mainly reduced between Sukkur Barrage and Guddu Barrage on Sindh-Punjab border.
The regional Sindh government declared the area between these two barrages as the Indus River Dolphin Reserve in 1974. The Reserve continues to harbour the majority of the population.
The grey-brown coloured dolphins, measuring between 1.5 and 2.5 meters in length and weighing a maximum of 90 kg, have been hunted for meat, oil and fin. They are considered by locals to have aphrodisiac qualities.
As these are air-breathing mammals, they often get caught in fishing nets set up by locals and drown.
The WWF and Pakistani wildlife department officials are encouraging the local fishermen to opt for other means of livelihood to save the remaining population of the precious dolphins.
‘We have managed to convince a large number of fishermen who now run ‘dolphin safaris’ in waters, where they once used to fish, for local and foreign tourists,’ added Garstang.