Physical Description
The species is characterized by a long beak, rounded belly, stocky body, very small dorsal fin and large flippers. Although its eye hasn't developed a lens (this species is also referred to as the "blind dolphin"), the dolphin still uses its eyes to differentiate between light and dark. It relies on echolocation (sound sensors) to find fish, shrimp, and other prey in the bottom mud.
The Indus River dolphin swims on its side, at times enabling it to move in water as shallow as 30 cm. As it swims on its side, it trails a flipper along the bottom of the river. After 30 to 60 seconds, when it needs to breath, it swims to the surface, rotates upright to take in the air, and then rotates 90 degrees again as it swims back to the bottom. This unique side swimming behaviour is not consistently seen in any other dolphin, except the Ganges River dolphin.
The Indus River dolphin migrates upstream into the smaller tributaries during the monsoon rains and migrates downstream to the main channels in the dry season.
Size
The Indus River dolphin weighs 70-110 kg (155-245 lbs). The maximum size is 2.5m (8.2 ft), with males smaller than females.