"One day, Plato defined humankind as the two-legged animal without feathers. The next day, they say, Diogenes dropped by at the Academy with a plucked chicken".
Known to locals as the bhulan, the Indus susu is today mainly confined to a 100-mile stretch of fresh water between two artificial constructions, the Guddu and the Sukkur barrages, across the lower Indus in the province of Sindh, Pakistan. The bhulan, even more than its neighbour in the Ganga, is threatened with imminent extinction. As is the case with the earth's other three river dolphin species, its fight for survival has not so much to do with adverse natural conditions as with problems manmade. Its diminishing numbers are a result of incidental and intentional exploitation by humans. A survey conducted jointly in 2001 by wwF-Pakistan, the Pakistan government wildlife departments and the Whale and Dolphin Conservation Society estimated that there are 1100 bhulans left in the Indus waters (see survey map). A total of 965 individuals were actually sighted.
Confined to the fresh-water river system of the Indus in Pakistan, the blind and side-swimming bhulan resembles the Indian susu in every respect, except that it is slightly smaller, as the specific name minor implies. Like other river dolphins, and unlike its ocean-going relatives, the bhulan has a bulbous forehead and a long rostrum, its skull has not undergone streamlining and the neck vertebrae are not fused, thereby allowing remarkable flexibility of the head, which may assist it in capturing prey, navigating in narrow waterways, and in scanning its surroundings. It too relies on echolocation to navigate and hunt. And, like the Ganga susu, the bhulan is a slow swimmer. Bhulans often swim on their right sides, nodding their heads continually, perhaps to maintain contact with the bottom of the river with their right flipper. Being quite blind, they appear to navigate through touch, the flipper serving much like a blind man's stick.
Up until the 1970s, the Indus bhulan (Platanista minor) was not distinguished from the Ganga susu (Platanista gangetica) as a separate species. But, noting other distinctive features, G Pilleri and M Gihr in their paper 'Zur Systematik der Gattung Platanista', Cetacea, 1971, argued that since no size difference has been systematically documented, it is more appropriate to call the dolphin of the Indus, Platanista indi.