9/13/20
Ganges River Dolphin
The Ganges River Dolphin is a freshwater dolphin that used to live in the Ganges-Brahmaputra-Meghna and Karnaphuli-Sangu river systems in India, Nepal, and Bangladesh. However, they are now mostly extinct in a lot of these areas. There are about 2000 animals left, divided almost equally into two almost identical subspecies. Dolphins are one of the oldest animals in the world along with turtles, crocodiles, and sharks, and the Ganges river dolphin is one of the first river dolphins. This dolphin can only survive in freshwaters. Because they live in very muddy waters, Ganges river dolphins do not rely much on eyesight. They are basically blind, and get around using echolocation, meaning they send out ultrasonic sounds that bounce off objects to create a picture, allowing dolphins to swim, move around, catch prey and occasionally communicate. Ganges river dolphins can often be found in small groups, such as a mother with a calf. Calves are brown skinned at birth, but adult Ganges river dolphins have grey skin. The Ganges river dolphins can usually be found in slow flowing rivers and in deep waters where they can find their prey of fish and invertebrates.
The main reason they are endangered are the effects of people and dolphins living in such close quarters. Ganges river dolphins live in one of the most densely populated areas in the world, which causes problems between people and the dolphins. For example, both dolphins and people are more likely to be around the places in the river with lots of fish and slow waters. This lowers the amount of fish that people can catch, and leads to dolphins dying because of bycatch, when dolphins accidentally get caught in fishing nets meant for other animals. Another reason the Ganges river dolphin is endangered is hunting. Dolphins are hunted for meat and oil, which can both be used medicinally, and the oil can also be used to attract catfish. Another problem facing the Ganges river dolphin is pollution. 6,009,000 tons of pesticides and fertilizers are used per year in and around the Ganges river, which can adversely affect prey, dolphins, and their habitats. Dolphins have often been found to have high levels of toxic chemicals in their bodies. Another problem is isolation of the dolphins. Because of dams and irrigation, many Ganges river dolphins are trapped and isolated in small groups. This exposes them to inbreeding and decreases genetic diversity. When dolphins are too close to dams they will also be threatened either by heavy pollution or poaching, depending on whether they're above or below the dams. The dams also disrupt the habitats and habits of fish, leaving less food for the dolphins.
Image courtesy of Elizabeth Fahrni Mansur
The Ganges river dolphin is important because it reliably shows how healthy the ecosystem is, as the health of the Ganges river dolphin is tied to the health of other animals and the river. Because of this, it was declared a National Aquatic Animal in 2009.
Organizations like the World Wildlife Fund are working on ways to reduce the damage caused by dams and irrigation, while not harming the people they help. It would also help, for people who live near the Ganges, to use natural fertilizers if possible. Organizations are also trying to reforest the riverbank and other ways to keep dolphins out of bycatch. You can also support policies that help dolphins and humans. You can help by donating to organizations helping dolphins.
Works Cited
“Ganges River Dolphin.” World Wildlife Fund. https://www.worldwildlife.org/species/ganges-river-dolphin. Accessed 24 August 2020.
“Ganges River Dolphin.” Edge of Existence. http://www.edgeofexistence.org/species/ganges-river-dolphin/. Accessed 24 August 2020.
Swinton, J. and W. Gomez 2009. "Platanista gangetica" (On-line), Animal Diversity Web. Accessed August 24, 2020 at https://animaldiversity.org/accounts/Platanista_gangetica/
*all pictures and videos used with permission, and/or taken from the sites above