Indus River Dolphin, also called Blind Dolphin is one of the world’s rarest mammals andthe second most endangered freshwater river dolphin. Approximately eleven hundred (1,100) individuals of this species now exist which is far less than their former number. The species is characterized by a long beak, rounded belly, very small dorgal fin and large flippers. These animals have a uniformly gray-colour pattern having a pale white or pinkish underside that gives a slight counter-shading effect. As this species matures, the melon becomes less rounded. The teeth are visible in both upper and lower jaws even when the mouth is closed. This species is called Blind Dolphins because their eyes are poorly-developed, they lack a crystalline eye lens but it still uses its eyes to differentiate between light and dark. The eyes are extremely small, resembling pinhole openings just above the mouth.
The Indus River Dolphin weighs 70-110 kilograms; maximum size is 2.5 meters (8.2feet). Their males are smaller then their females. A very unique feature of their swimming is their side swimming behavior. In its side swimming behavior, it enables itself to swim as shallow as thirty centimeters. As it swims, it trails a flipper along the bottom of the river. After thirty to sixty (30-60) seconds, when it needs to breath, it comes to the surface rotates upright to take in the breath and then as it swims back to bottom, it again rotates to ninety degree. This feature is not consistently seen in other dolphins except Ganges River Dolphin.
The Indus River Dolphin usually occurs in the deepest river channels and is less common in small channels and braids (animalinfo.org). Habitat preferences include channel constrictions, confluences and low-velocity deep water. It occurs in Indus River Delta and Rann of Kutch. It was apparently formerly distributed through thirty five hundred kilometers of the Indus River in Pakistan. It was present from the Himalayan foothills to the mouth of river Indus, and in the main tributaries from the Himalayan foothills to their junction with the Indus. By the early1970’s, its range sharply declined to less than seven hundred kilometers of the river length. The majority of the remaining population lived between Guddu and Sukhar barrage. The region still harbors the majority of the remaining population. As far as their social behaviour is concerned, they are usually encountered on their own or in loose aggregations; they do not form tight, obviously interacting groups.
The Indus River Dolphin usually feeds on different species of fish and invertebrates. It uses echolocation to find shrimp, fish and other prey in the bottom mud. It finds much of its prey at or near the bottom probing the river bottom with its snout and flipper.
This species is fighting a hard battle of its survival. The species is in a great danger. Its number has sharply declined for the past few years because of numerous factors. The river Indus is becoming more and more dirty and the water is being distributed into canals and dams which is giving this species a hard time for survival. The basic reason for the decline of Indus River Dolphin was the construction of numerous dams and barrages back in 1930’s, which have fragmented the population and reduced the amount of available habitat.
Another severe threat to its survival is probably the increasing withdrawl of water. Pakistan is an agricultural country and because of increasing population, there is a great demand for water. This is causing harm to the habitat of dolphins. Dolphins no longer exist in lower reaches of the river Indus because upstream water extraction leads downstream areas extremely dry for several months each year. Accidental capture in fishing nets and hunting for oil, meat and traditional medicines also had an impact.
Many initiatives have been taken for the protection of this species. In 1972, dolphins were protected by the government of Sindh under the wildlife act of Sindh and in 1974, the river between Sukhar and Guddu barrages was declared dolphin reserve. The government of Punjab prohibited the deliberate killing of dolphins in 1974 under Punjab Wildlife Protection Act and established the Taunsa Wildlife Sanctuary in 1983 and Chashma Wildlife Sanctuary in 1984 (iucnredlist.org). Moreover, many international programmes have also been initiated. Indus River Dolphin Conservation Project (IRDCP) is supported by WWF-Sweden, WWF-Switzerland, Engro Food limited and Ministry of Environment Pakistan Waterlands Program. It is working to protect innate biodiversity of the lower Indus river ecosystem, and reducing the losses of Indus river dolphins by canals stranding through rescue operations. Another one is Conservation of the Endangered Indus River Dolphin (CEIRD) by WWF.
Thus Indus River Dolphins are a great gift of nature for Pakistan, which is being harmed by our own activities. So we need to work for their survival and protection in order to save this species from being called extinct.
Written By: Nabeel Riaz Sandhu ( LUMS ).
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