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Article Evaluation: South Asian River Dolphin

The article gives a neutral perspective to the South Asian River dolphin. Information in the article is relevant and reliable. It lacked some citations, which would better improve the article. The article gives a general physical and biological description, along with habitat background. It lacked in more detailed topics like diet and offspring care.

There was previously different pages for the Ganges River Dolphin and the Indus River Dolphin but it was recently merged to the general South Asian River Dolphin page. Because this is merged together there can be separate sections discussing the differences between the two subspecies.

Foraging Strategy and Diet

The Ganges subspecies (P. g. gangetica) relies on echolocation to find prey due to their poor eyesight. Their extended rostrum is advantageous in detecting hidden or hard to find prey items. The prey is held in their jaw and swallowed. Their teeth is used as a clamp rather than a chewing mechanism.

This carnivorous subspecies primarily feeds on crustaceans, freshwater sharks, and various species from the family Cyprinidae. [1]

  1. ^ "Ganges River Dolphin (Platanista gangetica gangetica) - Dolphin Facts and Information". www.dolphins-world.com. Retrieved 2018-06-05.

Distribution and habitat

The South Asian river dolphins are native to the freshwater river systems located in Nepal, India, Bangladesh, and Pakistan. They can be most commonly found in water with high abundance of prey and reduced flow. (Added info) They migrate seasonally—downstream in colder conditions with lower water levels and upstream in warmer conditions with higher water levels. [1]

The Ganges subspecies (P. g. gangetica) can be found along the Ganges-Brahmaputra-Meghna and Karnaphuli-Sangu river systems of Bangladesh and India, although its range formerly extended to Nepal. A small subpopulation can be still found on the Ghaghara River and possibly the Sapta Kosi River.

The Indus subspecies (P. g. minor) today only occurs in a 1,000 km stretch of the Indus River itself and several connecting channels between the Jinnah and Kotri barrages. In the past it was to be found along 3,400 km of the Indus, its tributaries and neighboring river systems. Its range has contracted by about 80% since 1870. Since the two originally inhabited river systems - between the Sukkur and Guddu barrage in Pakistan's Sind Province, and in the Punjab and Khyber Pakhtunkhwa Provinces - are not connected in any way, it remains unknown how they were colonized. It is improbable that the river dolphins made it from one river to another through the sea route since the two estuaries are very far apart. A possible explanation is that several north Indian rivers like the Sutlej and Yamunachanged their channels in ancient times while retaining their dolphin populations.

  1. ^ Sinha, Ravindra K.; Kannan, Kurunthachalam (2014-12). "Ganges River Dolphin: An Overview of Biology, Ecology, and Conservation Status in India". Ambio. 43 (8): 1029–1046. doi: 10.1007/s13280-014-0534-7. ISSN  0044-7447. PMC  4235892. PMID  24924188. {{ cite journal}}: Check date values in: |date= ( help)CS1 maint: PMC format ( link)
From Wikipedia, the free encyclopedia

Article Evaluation: South Asian River Dolphin

The article gives a neutral perspective to the South Asian River dolphin. Information in the article is relevant and reliable. It lacked some citations, which would better improve the article. The article gives a general physical and biological description, along with habitat background. It lacked in more detailed topics like diet and offspring care.

There was previously different pages for the Ganges River Dolphin and the Indus River Dolphin but it was recently merged to the general South Asian River Dolphin page. Because this is merged together there can be separate sections discussing the differences between the two subspecies.

Foraging Strategy and Diet

The Ganges subspecies (P. g. gangetica) relies on echolocation to find prey due to their poor eyesight. Their extended rostrum is advantageous in detecting hidden or hard to find prey items. The prey is held in their jaw and swallowed. Their teeth is used as a clamp rather than a chewing mechanism.

This carnivorous subspecies primarily feeds on crustaceans, freshwater sharks, and various species from the family Cyprinidae. [1]

  1. ^ "Ganges River Dolphin (Platanista gangetica gangetica) - Dolphin Facts and Information". www.dolphins-world.com. Retrieved 2018-06-05.

Distribution and habitat

The South Asian river dolphins are native to the freshwater river systems located in Nepal, India, Bangladesh, and Pakistan. They can be most commonly found in water with high abundance of prey and reduced flow. (Added info) They migrate seasonally—downstream in colder conditions with lower water levels and upstream in warmer conditions with higher water levels. [1]

The Ganges subspecies (P. g. gangetica) can be found along the Ganges-Brahmaputra-Meghna and Karnaphuli-Sangu river systems of Bangladesh and India, although its range formerly extended to Nepal. A small subpopulation can be still found on the Ghaghara River and possibly the Sapta Kosi River.

The Indus subspecies (P. g. minor) today only occurs in a 1,000 km stretch of the Indus River itself and several connecting channels between the Jinnah and Kotri barrages. In the past it was to be found along 3,400 km of the Indus, its tributaries and neighboring river systems. Its range has contracted by about 80% since 1870. Since the two originally inhabited river systems - between the Sukkur and Guddu barrage in Pakistan's Sind Province, and in the Punjab and Khyber Pakhtunkhwa Provinces - are not connected in any way, it remains unknown how they were colonized. It is improbable that the river dolphins made it from one river to another through the sea route since the two estuaries are very far apart. A possible explanation is that several north Indian rivers like the Sutlej and Yamunachanged their channels in ancient times while retaining their dolphin populations.

  1. ^ Sinha, Ravindra K.; Kannan, Kurunthachalam (2014-12). "Ganges River Dolphin: An Overview of Biology, Ecology, and Conservation Status in India". Ambio. 43 (8): 1029–1046. doi: 10.1007/s13280-014-0534-7. ISSN  0044-7447. PMC  4235892. PMID  24924188. {{ cite journal}}: Check date values in: |date= ( help)CS1 maint: PMC format ( link)

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