The Indus is among the great rivers of the world. It originates from the mountains of Tibet and flows through Ladakh and Pakistan before entering the Arabian Sea near Karachi. On its 2000-mile journey it passes through the Himalayan and Karakoram mountain ranges, the fertile plains of the Punjab and vast desert of Sind, encountering a rich variety of wildlife during its journey. Among these species are resident and migratory birds, mammals, reptiles and fish, and particularly the Indus Dolphin (Platanista minor) or Bulhan, as it is known locally. It is a unique river cetacean that only occurs in Pakistan and one of most endangered Cetacean species of the world. Most dolphins and whales are found only in the sea, but the Indus River dolphin survives only in freshwater. Other river dolphin species occur in the Yangtze River in China, the Amazon & Orinoco in South America and the Ganges, Brahmaputra and Meghna River System in India, Bangladesh and Nepal.

What Makes the Indus Dolphin Unique?

The Indus River dolphin is a very unusual kind of cetacean. It is thought to have its origin in the ancient Tethys Sea, which dried up around fifty million years ago forcing the dolphin to adapt to its only remaining habitat - the rivers. Living in the turbid waters of the Indus for millions of years has meant that its sight has been replaced by a sophisticated sonar system known as echolocation, which it uses to steer and hunt underwater. This species represents a unique genome, an irreplaceable part of the biodiversity of life on earth. The Ganges dolphin, a similar relative of the Indus River dolphin, is a distinct species.

How many Indus Dolphins remain and where they live?

It is estimated that there are between 950 to 1000 Indus dolphins remaining in Pakistan. The species is listed as 'Endangered' by the World Conservation Union (IUCN). The largest population of approximately 600 exists in the Sindh Province between the Sukkur and Guddu barrages. Smaller populations occur further upstream between Guddu and Taunsa and Taunsa and Chasma Barrages.

Historically the dolphins existed from the Indus estuary up into the foothills of the Himalayas at Attock. They were also found in all major Indus tributaries, including upstream in the River Ravi. Since the construction of the Indus irrigation system, the dolphins have declined dramatically. Now they remain only in a short stretch of the main Indus River in small populations, which have been separated by impassable irrigation weirs or barrages across the Indus River.

Why it is called the Blind Indus Dolphin?

The Indus dolphin is functionally blind. However, this is not a disadvantage but an adaptation to living in a turbid river environment where eyes are virtually useless. Instead of eyesight, the dolphin has developed a high-tech echolocation or sonar system to 'see' and judge its environment. Sound pulses are emitted into the water through the 'melon' or bulge at the front of the dolphin's head. These sound pulses are reflected back to the dolphin to give it details of its surroundings. The Indus River dolphin can navigate and locate objects using this echolocation system. What remains of its eyes are now no bigger than a pinprick.

Mammal or fish?Although the Indus Dolphin looks like a fish, it is a mammal. Like humans it breathes air and gives birth to live young that feed on the mother's milk for up to two months.

The Appearance of the Indus Dolphin:

Take a close look at this picture. When you see the dolphins in the wild they swim so quickly that it is often difficult to see them clearly.

• Colour: Grey-brown

• Size: Maximum size 5.6 to 6.6 ft. Males are smaller than females.

• Eyes: The dolphin is a blind and ahs no lens in its tiny eyes.

• Teeth: Adults have between 30 and 36 sharp teeth on each side of the beak-like rostrum. The teeth at the end of the rostrum are very long, thin and protruding.

• Rostrum: River dolphins have a much longer rostrum than marine dolphins. It can be upto one fifth of the total body length.

• Blowhole: Dolphins breathe through a blowhole located on top of their heads.

• Neck:Unlike other dolphins, the Indus Dolphin's neck is relatively less thick and is more flexible. This aids movement in a complicated river environment.

• Flippers: The Bulhan has very broad flippers which it uses to man oeuvre and to stabilize it self in fast flowing water.

How does the Indus dolphin swim?

The Indus River dolphin swims on its side. As it swims it trails a side flipper along the bottom of the river and moves its tail form side to side like a fish. This behaviour enables the dolphin to swim in water as shallow as 30cm deep. The dolphin needs to breathe after every 60 to 160 seconds. It swims to the surface, rotates upright to take in air through its blowhole, and then rotates 90 again as it swims back to the bottom. This unique swimming behaviour it not seen in any other dolphin except the Ganges River Dolphin.

Why is the dolphin endangered?

Lack of Freshwater: Pakistan's huge irrigation scheme leaves very little water in the Indus River, particularly in winter, for the dolphins to live in.

Entrapment in Irrigation Canals: Dolphins are sometimes trapped in narrow irrigation canals where they eventually die.

Fishing: Over and irregulate fishing can reduce the dolphin's food. Also dolphins can become entangled in fishing nets in the river and drown.

Pollution: Chemicals in the Indus River System such as pesticides, organochlorines and industrial effluents penetrate the dolphin's body. This reduces their physical fitness making them more prone to illness and also causes reproductive problems.

Fragmented Habits: The Indus Blind dolphins have been split into several small populations separated by impassable barrages large dam-like structures across the Indus. These populations may be too small to survive and may suffer from inbreeding that can result in reduced health or physical deformities.

Hunting: In some places dolphin oil and body parts are sold and used as traditional medicine.