BULHAN The Incredible Indus River Dolphin

By Aftab Rana

Photographs credit: Sustainable Tourism Foundation Pakistan (STFP)

Dolphins and humans have been together for thousands of years. Ancient writings are full of stories about dolphins. They have helped one another at times, and they have even played together. 2500 years ago, the ancient Greek philosopher Aristotle wrote about dolphins talking to people. He noticed that dolphins sounded just like humans.

A 2000-year-old Greek coin shows a man riding a dolphin. An ancient wall painting found in a palace on the Island of Crete shows swimming dolphins. In ancient myths, dolphins were often mentioned for good luck and for being friendly to humans. They always appeared in the role of helping people.

The Dolphin Kingdom

There are 25 different kinds of saltwater dolphins and 4 kinds of freshwater dolphins, freshwater dolphins are only found in a few large rivers in Pakistan, India, China, and South America.

The Indus River Dolphin

The Indus River Dolphin (Platanista minor) is one of the world’s rarest mammals and most endangered cetaceans. Only about 1400 of this unique species exist today in the lower reaches of the Indus River in Pakistan.

Indus Dolphin (Platanista minor) or Bulhan, as it is known locally occurs only in the River Indus. It is ranked as one of the most intelligent living creatures after man. It lived here where it is now, as a sea animal about 70 million years ago. It managed to survive through its adaptations, and structural and functional transformations, the environmental pressures, and successfully changed from a marine to a freshwater habitat. Loss of vision due to living in the turbid and dark environment of Indus has been compensated by an extremely efficient sonar system to locate its path and even minute objects.

It now faces the threat of extinction at the hands of man, for its habitat has been reduced and fragmented due to a reduction in the quantity of water, fish, which is its food, and a constant increase in water toxicity.

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 disappeared around fifty million years ago. This dolphin adapted to the river habitat. Living in the turbid waters of the Indus in which underwater visibility was poor, a sophisticated sonar system known as echolocation gradually developed.

Did you know? The Indus River dolphin is one of the ‘world’s most endangered cetaceans.

It is estimated that there are between 1200 to 1400 blind dolphins remaining in Pakistan. The species is listed as “Endangered” by the World Conservation Union (IUCN). The largest population of approximately 700 exists in the Sindh provinces between the Sukkur and Guddu Barrages. Smaller populations of 465 and 96 occur further upstream between Guddu and Taunsa and Taunsa and Chasma Barrages. Historically the Dolphin existed from the Indus estuary up into the foothills of the Himalayas at Attack. They were also found in all major Indus Tributaries, including upstream in the River Ravi. Since the construction of the Indus irrigation System, the number of dolphins has 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. (The dolphin is now mainly confined to the range highlighted on the map).

The Appearance of the Indus Dolphin:

Take a close look at the Picture. When you see the Dolphins in the wild, they emerge momentarily so it is often difficult to see them clearly.

• Colour: Mostly Mid-gray-brown

• Eyes: the Indus dolphin is functionally blind and has no lens in its tiny eyes.

• Teeth: adults have between 30 and 36 sharp teeth on each side of the upper and lower jaws. The teeth at the end of the rostrum are longer and protruding.

• Rostrum: River dolphins have a much longer rostrum than oceanic dolphins. It can be up to one-fifth of the body length. The female usually has a longer rostrum than the male.

• Length and weight: the average length of an adult is 5 – 8 ½ feet and the weight of an adult is 70 to 90 Kg

• Blowhole: dolphins breathe through a blowhole located on the top of their head.

• Neck: the neck is relatively narrow and very flexible which helps the dolphins move in complicated river environments.

• Flippers: Bulhans have very broad flippers which stabilize them at slow speeds in fast-flowing water. Inside the flippers, dolphins have five fingers just like us.

• Life span: Scientists think that these dolphins can live for approximately 20 years.

• Diet: The Indus River dolphin eats crustaceans such as prawns, as well as fish such as gobies, catfish, and carp.

Why is it called the Blind Indus Dolphin?

The Indus Dolphin is functionally blind. However, this is not a disadvantage but an adaption to living in a turbid river environment where eyes are virtually useless. Instead of eyesight, the dolphin had developed a hightech 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. 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.

Why is the Indus River Dolphin Endangered?

• Lack of Freshwater: Extensive irrigation schemes mean that during winter months there is very little water left in

the Indus River for the Dolphin to live in.

• Drift in Irrigation Canals: sometimes dolphins drift into irrigation canals and become trapped in narrow channels where they die.

• Fish nets: Dolphins sometimes get entangled in fishing nets in the river and drown.

• Pollution: Chemicals in the Indus River such as pesticides and toxic industrial effluents. These enter the dolphin’s body and reduce their physical fitness making them more prone to illness and reproductive problems.

• Fragmented Habitat: Indus Dolphins have been split into several small populations separated by impassable barrages. The tiny populations may be too small to be viable and may suffer from inbreeding which can result in reduced fitness or physical deformities.

Where can we see Indus Dolphin?

Sustainable Tourism Foundation Pakistan has started a community-based ecotourism program in the area of Taunsa Barrage on the River Indus in south Punjab. Under this initiative, a local fishermen community social enterprise regularly runs boat safari trips for tourists who are interested in River Indus Dolphin watching.

About the Author

Aftab Rana is a Tourism Development Specialist. He is the President of Sustainable Tourism Foundation Pakistan and a Vice President of Adventure Foundation Pakistan. He is also presently serving as Honorary Managing Director of PTDC. He is also a Fellow of Leadership for Environment and Development.