Platanista minor
As with most river dolphins, this species is highly endangered.
Indus river dolphins look identical to Ganges river dolphins.
They inhabit the Indus river and tributaries.
Indus river dolphins feed on small fish and crustaceans.
They live singly or in pairs.
Unknown.
Indus river dolphins have a body length of 1.5-2.5m and weigh
70-90kg.
Indus river dolphins are classified as Endangered by the 2000
Red Data List, and there are only about 400 left. They are
probably one of the top ten most endangered mammals.
Ganges river dolphins are almost identical to Indus river
dolphins but are separated from them by land. They have some
internal differences to the Indus river dolphin, but look
the same on the outside and have similar habits. They are
the only cetaceans that don't have a crystalline eye lens,
which means that they are blind! So, to get around, they use
their well-developed echolocation system. It is so murky in
the water where they live, that good eyesight would be pretty
useless anyway! Their most striking feature is a long beak
which thickens towards the end. They don't have any patches
of colour on their stocky bodies but the colour of the animals
can range from greyish-blue, to blue or even chocolate brown.
They have round bellies.
The Ganges river dolphin ranges from 2.3 to 2.6 meters in
length. The tail fluke is on average 46cm in width. Females
are larger than males. The rostrum is 18 to 21cm in length
and the forehead is steep and rises abruptly from the base
of the snout. The dorsal fin is rudimentary and ridge-like,
and the ends of the pectoral fins are squared instead of tapered.
The neck is visibly constricted and the blowhole is a longitudinal
slit. There are 28 to 29 teeth on either side of the jaw.
The eye and optic nerve of the Ganges river dolphin are degenerate.
The eye lacks a lens and is therefore incapable of forming
images on the retina. However, it functions in light-detection.
It is believed that the lack of a true visual apparatus in
the river dolphin is related to its habitat; the water in
which it lives is so muddied that vision in essentially useless.
The Ganges River Dolphin is an endemic species of the Ganges,
Brahmaputra, and Meghna river systems, extending from the
foot of the Himalayas to the tidal zone in India, Bangladesh,
Nepal and Bhutan, and is an extremely docile and graceful
creature.
Commonly known as susu the Ganges River Dolphin are among
the four freshwater dolphin found in the world - the other
three are the baiji found in the Yangtze river in China, the
bhulan of the Indus in Pakistan and the buto of the river
Amazon in Latin America.
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