The Ganges river dolphin (also known as the south Asian river dolphin or Susu) is a freshwater dolphin that can be found swimming in the Ganges and Brahmaputra rivers of south Asia.
The Ganges river dolphin makes up one of two subspecies of dolphin within their group.
The other subspecies of dolphin is known as the Indus river dolphin, which can be found living in the Indus river.
Both dolphins belongs to the cetacean family and are part of the toothed whale suborder.
At birth the Ganges river dolphin appears to be a dark chocolate-brown color, however over time they begin to take on a grayish brown skin tone.
They have a long tapered body with a small fin located on the lower back and a long but narrow beak used for capturing food that may be hidden in narrow places or mud banks.
The Ganges river dolphin is blind.
In order to navigate the river and find food this dolphin uses echolocation which allows it to use echos to find objects in the environment and determine its size, distance, direction and density.
In terms of size the Ganges river dolphin may grow to an average of 7 1/2 – 9 ft in length and weigh between 330 – 380 pounds when fully matured.
At full maturity the female river dolphin will grow to be larger than their male counterparts.
The Ganges river dolphin can be found hunting a variety of freshwater fish and invertebrate such as catfish, clams and prawns.
Some researchers believe that these dolphins may also consume birds, small turtles and small freshwater sharks.
When it comes to hunting for food they generally hunt for prey living in shallow waters near the surface or in mud banks.
Although they have a large beak used for finding hidden and burrowed prey they are unable to chew the food they capture and only use their beak to grab onto their prey swallowing their food whole.
Due to their small population size the Ganges river dolphin can usually be found traveling alone or in small groups.
In order to communicate with one another these dolphins use a series of clicks and whistles and each dolphin produces a unique frequency allowing one dolphin to determine who is speaking in the group.
While not much is currently known about this species social structure in the past their species was much more abundant and affluent.
Before the rivers become largely populated by humans these dolphins could be found swimming together in large schools or pods, which appears to indicate that social hierarchy and family may have played an important role in their survival and day-to-day living.
The Ganges river dolphin is a non migratory species and is limited by the Ganges and Brahmaputra fresh water rivers they live in.
Unfortunately information regarding the Ganges river dolphins breeding habits is extremely limited.
It is estimated that female dolphins give birth to a single offspring once every two to three years and have an average lifespan of 20 – 30 years.
Like other species of dolphin the Ganges river dolphin may also feed their young by producing a thick milk out of their mammary glands, which the child suckles from its mothers nipple.
The thick paste like milk produced by many of the dolphin species allows the milk to travel through the water without breaking up, which allows the baby dolphin to capture the milk without fear of it being dissolved by the water.
In order to try to aid in the re-population of the Ganges river dolphin species some species have been held in captivity where they can be raised in an environment where they face very little threat, however even with these efforts it may not be enough to help these dolphins repopulate.
In the past the Ganges river dolphin was considered a very abundant species, however over the years their species has suffered significant losses in terms of population size and distribution.
Some of the threats these dolphins face include getting caught in fishing nets, the construction of dams, bridges and other foundations which limit their range and mobility, collisions with boats and other man-made transportation, overpopulation by humans, water pollution and occasional hunting (while hunting has been largely eliminated in most areas these dolphins still face threats from occasional poachers).
The Ganges river dolphin is an extremely endangered species with estimates of less than 2,000 dolphins currently in existence.