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{{Use dmy dates|date=December 2014}}
{{Use dmy dates|date=December 2014}}
{{merge from|Ganges river dolphin|date=April 2018}}
{{speciesbox
{{speciesbox


| fossil_range = {{Fossil range|20|0}}<small>Late [[Miocene]] – Recent<ref>{{cite web|title=Platanistidae fossilworks|url=http://fossilworks.org/ Platanistidae}}</ref>
| fossil_range = {{Fossil range|0.012|0}}<small>[[Quaternary]] – Recent<ref name=fossilworks>{{cite web|title=Platanista Wagler 1830 (toothed whale)|url=http://fossilworks.org/?a=taxonInfo&taxon_no=63564|website=Fossilworks}}</ref>
| name = South Asian river dolphin
| name = South Asian river dolphin
| status = EN
| status = EN
| status_system = IUCN3.1
| status_system = IUCN3.1
| status_ref = <ref name=iucn>{{cite journal | author = Smith, B.D. | author2 = Braulik, G.T. | title = ''Platanista gangetica'' | journal = [[IUCN Red List of Threatened Species]] | volume= 2012 | page = e.T41758A17355810 | publisher = [[IUCN]] | year = 2012 | url = http://www.iucnredlist.org/details/41758/0 | doi = 10.2305/IUCN.UK.2012.RLTS.T41758A17355810.en | accessdate = 29 August 2016}}</ref>
| status_ref = <ref name=iucn>{{cite journal | author = Smith, B.D. | author2 = Braulik, G.T. | title = ''Platanista gangetica'' | journal = [[IUCN Red List of Threatened Species]] | volume= 2017 | page = e.T41758A50383612 | publisher = [[IUCN]] | year = 2017 | url = http://dx.doi.org/10.2305/IUCN.UK.2017-3.RLTS.T41758A50383612.en| doi = 10.2305/IUCN.UK.2017-3.RLTS.T41758A50383612.en | accessdate = 29 May 2018}}</ref>
| image =Platanista gangetica noaa.jpg
| image =Platanista gangetica noaa.jpg
| image_caption = Ganges river dolphin leaping out of the water
| image_caption = Ganges river dolphin leaping out of the water
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}}
}}


The '''South Asian river dolphin''' (''Platanista gangetica'') is a freshwater or [[river dolphin]] found in the [[Indian subcontinent]] which is split into two subspecies, the [[Ganges river dolphin]] (1,200-1,800 individuals) (''P. g. gangetica'') and the [[Indus river dolphin]] (''P. g. minor'').<ref>{{cite book |url=https://books.google.com/books?id=5_G608B-zTwC&pg=PA8&dq=south+asian+river+dolphin#v=onepage&q=south%20asian%20river%20dolphin&f=false |title=Marine mammal biology: an evolutionary approach|author=A. Rus Hoelzel|page=8|publisher=Wiley-Blackwell, 2002 |accessdate=2011-02-10 }}</ref> The [[Ganges river dolphin]] is primarily found in the [[Ganges]] and [[Brahmaputra River|Brahmaputra]] Rivers and their tributaries in Bangladesh, India and Nepal, while the [[Indus river dolphin]] is found in the [[Indus River]] in [[Pakistan]] and its [[Beas River|Beas]] and [[Sutlej]] tributaries. From the 1970s until 1998, they were regarded as separate species; however, in 1998, their classification was changed from two separate species to subspecies of a single species (see taxonomy below). The [[Ganges river dolphin]] has been recognized by the government of [[India]] as its [[List of national animals|National Aquatic Animal]].<ref>{{Cite web|url=http://www.moef.nic.in/sites/default/files/dolphin-eng_0.pdf|title=Declaration of Gangetic Dolphin as National Aquatic Animal|last=|first=|date=10 May 2010|website=Government of India - Ministry of Environment, Forest and Climate Change|publisher=|access-date=23 October 2016}}</ref> The Indus river dolphin has been named as the [[List of national animals|National Mammal]] of Pakistan.<ref>{{Cite web|url=http://www.pakistan.gov.pk/national_symbols.html|title=The Official Web Gateway to Pakistan|website=www.pakistan.gov.pk|access-date=2016-10-23|deadurl=yes|archiveurl=https://web.archive.org/web/20161128073024/http://www.pakistan.gov.pk/national_symbols.html|archivedate=28 November 2016|df=dmy-all}}</ref> Further, the [[Ganges river dolphin]] is the official animal of the Indian city of [[Guwahati]].<ref>{{cite news |title=Gangetic river dolphin to be city animal of Guwahati |url=http://timesofindia.com/home/environment/flora-fauna/Gangetic-river-dolphin-to-be-city-animal-of-Guwahati/articleshow/52623206.cms |newspaper=The Times of India |date=6 June 2016}}</ref>
The '''South Asian river dolphin''' (''Platanista gangetica'') is a freshwater or [[river dolphin]] found in the [[Indian subcontinent]] which is split into two subspecies, the [[Ganges river dolphin]] (1,200-1,800 individuals) (''P. g. gangetica'') and the [[Indus river dolphin]] (''P. g. minor'').<ref>{{cite book |url=https://books.google.com/books?id=5_G608B-zTwC&pg=PA8&dq=south+asian+river+dolphin#v=onepage&q=south%20asian%20river%20dolphin&f=false |title=Marine mammal biology: an evolutionary approach|author=A. Rus Hoelzel|page=8|publisher=Wiley-Blackwell, 2002 |accessdate=2011-02-10 }}</ref> The [[Ganges river dolphin]] is primarily found in the [[Ganges]] and [[Brahmaputra River|Brahmaputra]] Rivers and their tributaries in Bangladesh, India and Nepal, while the [[Indus river dolphin]] is now found only in the main channel of the [[Indus River]] in [[Pakistan]] and active channels connected to it between the Jinnah and Kotri barrages. From the 1970s until 1998, they were regarded as separate species; however, in 1998, their classification was changed from two separate species to subspecies of a single species (see taxonomy below). The [[Ganges river dolphin]] has been recognized by the government of [[India]] as its [[List of national animals|National Aquatic Animal]].<ref>{{Cite web|url=http://www.moef.nic.in/sites/default/files/dolphin-eng_0.pdf|title=Declaration of Gangetic Dolphin as National Aquatic Animal|last=|first=|date=10 May 2010|website=Government of India - Ministry of Environment, Forest and Climate Change|publisher=|access-date=23 October 2016}}</ref> The Indus river dolphin has been named as the [[List of national animals|National Mammal]] of Pakistan.<ref>{{Cite web|url=http://www.pakistan.gov.pk/national_symbols.html|title=The Official Web Gateway to Pakistan|website=www.pakistan.gov.pk|access-date=2016-10-23|deadurl=yes|archiveurl=https://web.archive.org/web/20161128073024/http://www.pakistan.gov.pk/national_symbols.html|archivedate=28 November 2016|df=dmy-all}}</ref> Further, the [[Ganges river dolphin]] is the official animal of the Indian city of [[Guwahati]].<ref>{{cite news |title=Gangetic river dolphin to be city animal of Guwahati |url=http://timesofindia.com/home/environment/flora-fauna/Gangetic-river-dolphin-to-be-city-animal-of-Guwahati/articleshow/52623206.cms |newspaper=The Times of India |date=6 June 2016}}</ref>


==Taxonomy==
==Taxonomy==
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The South Asian river dolphins are native to the freshwater river systems located in [[Nepal]], [[India]], [[Bangladesh]], and [[Pakistan]].<ref name=iucn /> They can be most commonly found in water with high abundance of prey and reduced flow.<ref name=EDGE>{{cite web|title=South Asian river dolphin (Platanista gangetica)|url=http://www.edgeofexistence.org/mammals/species_info.php?id=65|publisher=EDGE|accessdate=26 July 2011}}</ref>
The South Asian river dolphins are native to the freshwater river systems located in [[Nepal]], [[India]], [[Bangladesh]], and [[Pakistan]].<ref name=iucn /> They can be most commonly found in water with high abundance of prey and reduced flow.<ref name=EDGE>{{cite web|title=South Asian river dolphin (Platanista gangetica)|url=http://www.edgeofexistence.org/mammals/species_info.php?id=65|publisher=EDGE|accessdate=26 July 2011}}</ref>


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.<ref name=EDGE /> A small subpopulation can be still found on the [[Ghaghara River]] and possibly the Sapta Kosi River. The majority of the Indus subspecies (''P. g. minor'') is located between the Sukkur and Guddu barrage in the [[Sindh|Sind Province]] of Pakistan.<ref name=EDGE /> Two smaller subpopulations have also been recorded in the [[Punjab Province (Pakistan)|Punjab]] and [[Khyber Pakhtunkhwa]] Provinces. Since the two river systems are not connected in any way, it is a mystery how these sub-species ended up in the two rivers. 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. According to ''Land of the Seven Rivers: A Brief History of India's Geography'' by [[Sanjeev Sanyal]], a likely explanation is that several north Indian rivers like the Sutlej and Yamuna changed their path in ancient times and carried the dolphins with them.<ref>{{cite book|last=Sanyal|first=Sanjeev|title=Land of the Seven Rivers: A Brief History of India's Geography|year=2012|publisher=Penguin}}</ref>
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.<ref name=EDGE /> 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&nbsp;km stretch of the Indus River itself and several connecting channels between the Jinnah and Kotri barrages.<ref>{{cite web|url=http://www.wwfpak.org/species/indus_dolphin.php|title=Indus River Dolphin|publisher=WWF Pakistan}}</ref> In the past it was to be found along 3,400&nbsp;km of the Indus, its tributaries and neighboring river systems. Its range has contracted by about 80% since 1870.<ref name=Braulik/> 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 [[Yamuna]] changed their channels in ancient times while retaining their dolphin populations.<ref>{{cite book|last=Sanyal|first=Sanjeev|title=Land of the Seven Rivers: A Brief History of India's Geography|year=2012|publisher=Penguin}}</ref>


==Biology==
==Biology==
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Births may take place year round, but appear to be concentrated between December to January and March to May.<ref name=CMS>{{cite web|author=Boris Culik|title=Platanista gangetica (Roxburgh, 1801)|url=http://www.cms.int/reports/small_cetaceans/data/P_gangetica/p_gangetica.htm|publisher=CMS Report|accessdate=24 July 2011|deadurl=yes|archiveurl=https://web.archive.org/web/20110611110231/http://www.cms.int/reports/small_cetaceans/data/P_gangetica/p_gangetica.htm|archivedate=11 June 2011|df=dmy-all}}</ref> Gestation is thought to be approximately 9–10 months. After around one year, juveniles are weaned and they reach sexual maturity at about 10 years of age.<ref>{{cite web|title=Platanista gangetica|url=http://animaldiversity.ummz.umich.edu/site/accounts/information/Platanista_gangetica.html|publisher=Animal Diversity Web|accessdate=24 July 2011|author=Swinton, J.|author2=W. Gomez|author3=P. Myer|last-author-amp=yes}}</ref> During the monsoon, South Asian river dolphins tend to migrate to [[tributaries]] of the main river systems.<ref name=CMS /> Occasionally, individuals swim along with their beaks emerging from the water,<ref name=wdcs>{{cite web|title=The Whale and Dolphin Conservation Society|url=http://www.wdcs.org/|accessdate=24 July 2011}}</ref> and they may "breach"; jumping partly or completely clear of the water and landing on their sides.<ref name=wdcs />
Births may take place year round, but appear to be concentrated between December to January and March to May.<ref name=CMS>{{cite web|author=Boris Culik|title=Platanista gangetica (Roxburgh, 1801)|url=http://www.cms.int/reports/small_cetaceans/data/P_gangetica/p_gangetica.htm|publisher=CMS Report|accessdate=24 July 2011|deadurl=yes|archiveurl=https://web.archive.org/web/20110611110231/http://www.cms.int/reports/small_cetaceans/data/P_gangetica/p_gangetica.htm|archivedate=11 June 2011|df=dmy-all}}</ref> Gestation is thought to be approximately 9–10 months. After around one year, juveniles are weaned and they reach sexual maturity at about 10 years of age.<ref>{{cite web|title=Platanista gangetica|url=http://animaldiversity.ummz.umich.edu/site/accounts/information/Platanista_gangetica.html|publisher=Animal Diversity Web|accessdate=24 July 2011|author=Swinton, J.|author2=W. Gomez|author3=P. Myer|last-author-amp=yes}}</ref> During the monsoon, South Asian river dolphins tend to migrate to [[tributaries]] of the main river systems.<ref name=CMS /> Occasionally, individuals swim along with their beaks emerging from the water,<ref name=wdcs>{{cite web|title=The Whale and Dolphin Conservation Society|url=http://www.wdcs.org/|accessdate=24 July 2011}}</ref> and they may "breach"; jumping partly or completely clear of the water and landing on their sides.<ref name=wdcs />


The South Asian river dolphin feeds on a variety of [[shrimp]] and fish, including [[carp]] and [[catfish]]. They are usually encountered on their own or in loose aggregations; the dolphins do not form tight interacting groups.
The South Asian river dolphin feeds on a variety of [[shrimp]] and fish, including [[carp]] and [[catfish]]. The Ganges subspecies may take birds and turtles. They are usually encountered on their own or in loose aggregations; the dolphins do not form tight interacting groups.<ref>{{cite web|url=https://www.dolphins-world.com/indus-river-dolphin/|title=Indus River Dolphin (Platanista gangetica minor)|publisher=Dolphins-World|access-date=29 May 2018}}</ref><ref>{{cite web|url=https://www.dolphins-world.com/ganges-river-dolphin/|title=Ganges River Dolphin (Platanista gangetica gangetica)|website=Dolphins-World|access-date=29 May 2018}}</ref>


==Conservation==
==Conservation==
{{see also|Vikramshila Gangetic Dolphin Sanctuary}}
{{see also|Vikramshila Gangetic Dolphin Sanctuary}}
⚫
International trade is prohibited by the listing of the South Asian river dolphin on Appendix I of the [[Convention on International Trade in Endangered Species]] (CITES).<ref>{{cite web|title=CITES|url=http://www.cites.org/|publisher=CITES|accessdate=24 July 2011}}</ref> It is protected under the Indian Wildlife Act, although these legislations require stricter enforcement.<ref name=CMS />


A 2017 population assessment estimated less than 5,000 individuals for the species as a whole, of which about 2,000 belong to the Indus subspecies. However, the underlying surveys are temporally pathcy and believed to contain a large amount of uncertainty. Current population trends are unclear. A demonstrable increase in the main river population of the Indus subspecies between 1974 and 2008 may have been driven by permanent immigration from upstream tributaries, where the species no longer occurs.<ref name=iucn/>
Both subspecies are listed by the [[IUCN]] as endangered on their [[Red List of Threatened Species]].<ref name=iucn/> The Indus river dolphin is listed as endangered by the US government [[National Marine Fisheries Service]] under the [[Endangered Species Act]]. On a positive note, in recent years, the population of blind Indus dolphins in Pakistan has increased.<ref>{{cite web|title=Blind Indus dolphins' population increasing|url=http://www.dawn.com/news/622216/blind-indus-dolphins-population-increasin|publisher=Dawn metropolitan|author=Bhagwandas}}</ref>


⚫
International trade is prohibited by the listing of the South Asian river dolphin on Appendix I of the [[Convention on International Trade in Endangered Species]] (CITES).<ref>{{cite web|title=CITES|url=http://www.cites.org/|publisher=CITES|accessdate=24 July 2011}}</ref> It is protected under the Indian Wildlife Act, although these legislations require stricter enforcement.<ref name=CMS /> Both subspecies are listed by the [[IUCN]] as endangered on their [[Red List of Threatened Species]].<ref name=iucn/> The Indus river dolphin is listed as endangered by the US government [[National Marine Fisheries Service]] under the [[Endangered Species Act]].
The immediate danger for the resident population of ''P. gangeticus'' in [[National Chambal Sanctuary]] is the decrease in river depth and appearance of sand bars dividing the river course into smaller segments.<ref name=Sing>{{cite journal | author1 = Singh, L.A.K. | author2 = R.K. Sharma | lastauthoramp = yes | year = 1985 | title = Gangetic dolphin, ''Platanista gangetica'': Observations on habits and distribution pattern in National Chambal Sanctuary | url = http://www.geocities.com/laksingh33/ch_dol.PDF | journal = Journal of the Bombay Natural History Society | volume = 82 | pages = 648–653 | publisher = Bombay Natural History Society | archive-url = https://www.webcitation.org/query?url=http://www.geocities.com/laksingh33/ch_dol.PDF&date=2009-10-26+01:37:44 | archive-date = 26 October 2009 | deadurl = yes | df = dmy-all }}</ref> The proposed conservation measures include designated dolphin sanctuaries and the creation of additional habitat.


⚫
The species is listed on Appendix I<ref name="Appendices">"[http://www.cms.int/documents/appendix/Appendices_COP9_E.pdf Appendix I and Appendix II] {{webarchive |url=https://web.archive.org/web/20110611112003/http://www.cms.int/documents/appendix/Appendices_COP9_E.pdf |date=11 June 2011 }}" of the Convention on the Conservation of Migratory Species of Wild Animals (CMS). As amended by the Conference of the Parties in 1985, 1988, 1991, 1994, 1997, 1999, 2002, 2005 and 2008. Effective: 5 March 2009.</ref> and Appendix II<ref name="Appendices" /> of the [[Convention on Migratory Species|Convention on the Conservation of Migratory Species of Wild Animals]] (CMS).
⚫
The Ministry of Environment and Forest declared the Gangetic dolphin as national aquatic animal of India. Also, a stretch of Ganges river between Sultanganj and Kahlgaon in Bihar has been declared as dolphin sanctuary and named Vikramshila Gangetic Dolphin Sanctuary (VGDS). It is the world's first dolphin sanctuary for the conservation of Gangetic Dolphin P. Gangeticus.


⚫
The Ministry of Environment and Forest declared the Gangetic dolphin the national aquatic animal of India. A stretch of the Ganges River between Sultanganj and Kahlgaon in Bihar has been declared a dolphin sanctuary and named [[Vikramshila Gangetic Dolphin Sanctuary]] (VGDS), the first such protected area.
⚫
The species is listed on Appendix I<ref name="Appendices">"[http://www.cms.int/documents/appendix/Appendices_COP9_E.pdf Appendix I and Appendix II] {{webarchive |url=https://web.archive.org/web/20110611112003/http://www.cms.int/documents/appendix/Appendices_COP9_E.pdf |date=11 June 2011 }}" of the Convention on the Conservation of Migratory Species of Wild Animals (CMS). As amended by the Conference of the Parties in 1985, 1988, 1991, 1994, 1997, 1999, 2002, 2005 and 2008. Effective: 5 March 2009.</ref> and Appendix II<ref name="Appendices" /> of the [[Convention on Migratory Species|Convention on the Conservation of Migratory Species of Wild Animals]] (CMS). It is listed on Appendix I<ref name="Appendices" /> as this species has been categorized as being in danger of extinction throughout all or a significant proportion of their range and CMS Parties strive towards strictly protecting these animals, conserving or restoring the places where they live, mitigating obstacles to migration and controlling other factors that might endanger them. It is listed on Appendix II<ref name="Appendices" /> as it has an unfavourable conservation status or would benefit significantly from international co-operation organised by tailored agreements.


The Uttar Pradesh government in India is bringing up ancient Hindu texts in hopes of raising the community support to save the dolphins from disappearing. One of the lines being versed from Valimiki’s Ramayan, highlighted the force by which the Ganges emerged from Lord Shivji’s locks and along with this force came many species such as animals, fish and the Shishumaar—the dolphin.<ref>{{cite web|title=How Hinduism Continues to Save Dolphins in India|url=http://www.chakranews.com/how-hinduism-continues-to-save-dolphins-in-india/964|publisher=The Chakra News}}</ref>
The Uttar Pradesh government in India is propagating ancient Hindu texts in hopes of raising the community support to save the dolphins from disappearing. One of the lines being versed from Valimiki’s Ramayan, highlighted the force by which the Ganges emerged from Lord Shivji’s locks and along with this force came many species such as animals, fish and the Shishumaar—the dolphin.<ref>{{cite web|title=How Hinduism Continues to Save Dolphins in India|url=http://www.chakranews.com/how-hinduism-continues-to-save-dolphins-in-india/964|publisher=The Chakra News}}</ref>


==Human interaction==
==Human interaction==
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[[File:GangeticDolphin.jpg|thumb|Gangetic dolphin, 1894 book illustration]]
[[File:GangeticDolphin.jpg|thumb|Gangetic dolphin, 1894 book illustration]]


Both subspecies have been very adversely affected by human use of the river systems in the subcontinent. Entanglement in fishing nets can cause significant damage to local population numbers. Some individuals are still taken each year and their oil and meat used as a liniment, as an [[aphrodisiac]], and as bait for [[catfish]]. Irrigation has lowered water levels throughout both subspecies' ranges. Poisoning of the water supply from industrial and agricultural chemicals may have also contributed to population decline. Perhaps the most significant issue is the building of more than 50 dams along many rivers, causing the segregation of populations and a narrowed [[gene pool]] in which dolphins can breed. Currently, three subpopulations of Indus dolphins are considered capable of long-term survival if protected.<ref name=Braulik>{{cite journal | author = Braulik, G. T. | year = 2006 | title = Status assessment of the Indus river dolphin, ''Platanista minor minor'', March–April 2001 | journal = Biological Conservation | volume = 129 | pages = 579–590 | doi = 10.1016/j.biocon.2005.11.026}}</ref>
Both subspecies have been very adversely affected by human use of the river systems in the subcontinent. Entanglement in fishing nets can cause significant damage to local population numbers. Some individuals are still taken each year and their oil and meat used as a liniment, as an [[aphrodisiac]], and as bait for [[catfish]]. Irrigation has lowered water levels throughout both subspecies' ranges. Poisoning of the water supply from industrial and agricultural chemicals may have also contributed to population decline. Perhaps the most significant issue is the building of more than 50 dams along many rivers, causing the segregation of populations and a narrowed [[gene pool]] in which dolphins can breed.<ref name=Braulik>{{cite journal | author = Braulik, G. T. | year = 2006 | title = Status assessment of the Indus river dolphin, ''Platanista minor minor'', March–April 2001 | journal = Biological Conservation | volume = 129 | pages = 579–590 | doi = 10.1016/j.biocon.2005.11.026}}</ref> An immediate danger for the Ganges subspecies in [[National Chambal Sanctuary]] is the decrease in river depth and appearance of sand bars dividing the river course into smaller segments.<ref name=Sing>{{cite journal | author1 = Singh, L.A.K. | author2 = R.K. Sharma | lastauthoramp = yes | year = 1985 | title = Gangetic dolphin, ''Platanista gangetica'': Observations on habits and distribution pattern in National Chambal Sanctuary | url = http://www.geocities.com/laksingh33/ch_dol.PDF | journal = Journal of the Bombay Natural History Society | volume = 82 | pages = 648–653 | publisher = Bombay Natural History Society | archive-url = https://www.webcitation.org/query?url=http://www.geocities.com/laksingh33/ch_dol.PDF&date=2009-10-26+01:37:44 | archive-date = 26 October 2009 | deadurl = yes | df = dmy-all }}</ref>


== Non-human personhood ==
=== Non-human personhood ===
On 20 May 2013 India’s Ministry of Environment and Forests declared dolphins as ‘non-human persons’ and as such has forbidden their captivity for entertainment purposes.<ref>{{Cite news|url=http://www.thehindu.com/features/kids/dolphins-get-their-due/article6119256.ece|title=Dolphins get their due|last=Gautama|first=Madhulika|date=2014-06-16|newspaper=The Hindu|language=en-IN|issn=0971-751X|access-date=2016-11-27}}</ref> Some scientists postulate that dolphins and whales are sufficiently intelligent to justify the same ethical considerations as humans.<ref>{{Cite news|url=http://www.bbc.com/news/world-17116882|title=Dolphins deserve same rights as humans, say scientists|date=2012-02-21|newspaper=BBC News|language=en-GB|access-date=2016-11-27}}</ref> As a consequence in order to keep dolphins in captivity one must provide a legally sufficient reason for their captivity.
On 20 May 2013 India’s Ministry of Environment and Forests declared dolphins ‘non-human persons’ and as such has forbidden their captivity for entertainment purposes; keeping dolphins in captivity must satisfy certain legal prerequisites.<ref>{{Cite news|url=http://www.thehindu.com/features/kids/dolphins-get-their-due/article6119256.ece|title=Dolphins get their due|last=Gautama|first=Madhulika|date=2014-06-16|newspaper=The Hindu|language=en-IN|issn=0971-751X|access-date=2016-11-27}}</ref>


== See also ==
== See also ==
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{{refbegin}}
{{refbegin}}
* {{RefAudubonMarineMammals}}
* {{RefAudubonMarineMammals}}
* {{IUCN2008|assessor=Smith, B. D.|assessor2=G. T. Braulik|assessor3=R. K. Sinha|last-assessor-amp=yes|year=2004|id=41756|title=Platanista gangetica gangetica|downloaded=14 November 2008}}
* {{IUCN2008|assessor=Smith, B. D.|assessor2=G. T. Braulik|assessor3=A. A. Chaudhry|last-assessor-amp=yes|year=2004|id=41757|title=Platanista gangetica minor|downloaded=14 November 2008}}
* [https://web.archive.org/web/20120316003657/http://www.nation.com.pk/pakistan-news-newspaper-daily-english-online/karachi/09-Mar-2012/blind-dolphins-need-space-to-breath Blind dolphins need space to breath] - [[The Nation (Pakistan)]]
* [https://web.archive.org/web/20120316003657/http://www.nation.com.pk/pakistan-news-newspaper-daily-english-online/karachi/09-Mar-2012/blind-dolphins-need-space-to-breath Blind dolphins need space to breath] - [[The Nation (Pakistan)]]
{{refend}}
{{refend}}
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* [http://www.press.jhu.edu/books/walkers_mammals_of_the_world/cetacea/cetacea.platanistidae.platanista.html Walker's Mammals of the World Online - Ganges River Dolphin]
* [http://www.press.jhu.edu/books/walkers_mammals_of_the_world/cetacea/cetacea.platanistidae.platanista.html Walker's Mammals of the World Online - Ganges River Dolphin]
* [http://wwf.panda.org/what_we_do/endangered_species/cetaceans/about/river_dolphins/ganges_river_dolphin/ World Wide Fund for Nature (WWF) - species profile for the Ganges River dolphin]
* [http://wwf.panda.org/what_we_do/endangered_species/cetaceans/about/river_dolphins/ganges_river_dolphin/ World Wide Fund for Nature (WWF) - species profile for the Ganges River dolphin]
* [https://www.youtube.com/watch?v=8_m6RyncoA4 Ganges River dolphin footage on YouTube]


{{Cetacea|O.1}}
{{Cetacea|O.1}}

Revision as of 15:02, 29 May 2018

South Asian river dolphin
Temporal range: 0.012–0 Ma
↓
Quaternary – Recent[1]
File:Platanista gangetica noaa.jpg
Ganges river dolphin leaping out of the water
Size compared to an average human
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Infraorder: Cetacea
Family: Platanistidae
Gray, 1846
Genus: Platanista
Wagler, 1830
Species:
P. gangetica
Binomial name
Platanista gangetica
(Lebeck, 1801); (Roxburgh, 1801)
Subspecies

Platanista gangetica gangetica
Platanista gangetica minor

Ranges of the Ganges river dolphin and of the Indus river dolphin

The South Asian river dolphin (Platanista gangetica) is a freshwater or river dolphin found in the Indian subcontinent which is split into two subspecies, the Ganges river dolphin (1,200-1,800 individuals) (P. g. gangetica) and the Indus river dolphin (P. g. minor).[3] The Ganges river dolphin is primarily found in the Ganges and Brahmaputra Rivers and their tributaries in Bangladesh, India and Nepal, while the Indus river dolphin is now found only in the main channel of the Indus River in Pakistan and active channels connected to it between the Jinnah and Kotri barrages. From the 1970s until 1998, they were regarded as separate species; however, in 1998, their classification was changed from two separate species to subspecies of a single species (see taxonomy below). The Ganges river dolphin has been recognized by the government of India as its National Aquatic Animal.[4] The Indus river dolphin has been named as the National Mammal of Pakistan.[5] Further, the Ganges river dolphin is the official animal of the Indian city of Guwahati.[6]

Taxonomy

The species was described by two separate authors, Lebeck and Roxburgh, in 1801, and it is unclear to whom the original description should be ascribed.[7] Until the 1970s, the South Asian river dolphin was regarded as a single species. The two subspecies are geographically separate and have not interbred for many hundreds if not thousands of years. Based on differences in skull structure, vertebrae and lipid composition scientists declared the two populations as separate species in the early 1970s.[8] In 1998, the results of these studies were questioned and the classification reverted to the pre-1970 consensus of a single species containing two subspecies until the taxonomy could be resolved using modern techniques such as molecular sequencing. The latest analyses of mitochondrial DNA of the two populations did not display the variances needed to support their classification as separate species.[9] Thus, at present, a single species with two subspecies is recognized in the genus Platanista, P. g. gangetica (Ganges river dolphin) and P. g. minor (Indus river dolphin).[10]

Synonyms
  • blind river dolphin, side-swimming dolphin
  • Ganges subspecies: Gangetic dolphin, Ganges susu,[11] shushuk
  • Indus subspecies: bhulan, Indus dolphin, Indus blind dolphin

Description

Indus river dolphin, 1927 illustration

The South Asian river dolphin has the long, pointed nose characteristic of all river dolphins. Their teeth are visible in both the upper and lower jaws even when the mouth is closed. The teeth of young animals are almost an inch long, thin and curved; however, as animals age, the teeth undergo considerable changes and in mature adults become square, bony, flat disks. The snout thickens towards its end. The species does not have a crystalline eye lens, rendering it effectively blind, although it may still be able to detect the intensity and direction of light. Navigation and hunting are carried out using echolocation.[12] They are unique among cetaceans in that they swim on their sides.[13] The body is a brownish color and stocky at the middle. The species has only a small, triangular lump in the place of a dorsal fin. The flippers and tail are thin and large in relation to the body size, which is about 2-2.2 meters in males and 2.4-2.6 m in females. The oldest recorded animal was a 28-year-old male, 199 cm in length.[14] Mature females are larger than males. Sexual dimorphism is expressed after females reach about 150 cm (59 in); the female rostrum continues to grow after the male rostrum stops growing, eventually reaching approximately 20 cm (7.9 in) longer.

Distribution and habitat

The South Asian river dolphins are native to the freshwater river systems located in Nepal, India, Bangladesh, and Pakistan.[2] They can be most commonly found in water with high abundance of prey and reduced flow.[12]

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.[12] 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.[15] 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.[16] 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 Yamuna changed their channels in ancient times while retaining their dolphin populations.[17]

Biology

Skull cast
Ganges river dolphin skeleton specimen exhibited in Museo di storia naturale e del territorio dell'Università di Pisa

Births may take place year round, but appear to be concentrated between December to January and March to May.[18] Gestation is thought to be approximately 9–10 months. After around one year, juveniles are weaned and they reach sexual maturity at about 10 years of age.[19] During the monsoon, South Asian river dolphins tend to migrate to tributaries of the main river systems.[18] Occasionally, individuals swim along with their beaks emerging from the water,[20] and they may "breach"; jumping partly or completely clear of the water and landing on their sides.[20]

The South Asian river dolphin feeds on a variety of shrimp and fish, including carp and catfish. The Ganges subspecies may take birds and turtles. They are usually encountered on their own or in loose aggregations; the dolphins do not form tight interacting groups.[21][22]

Conservation

See also: Vikramshila Gangetic Dolphin Sanctuary

A 2017 population assessment estimated less than 5,000 individuals for the species as a whole, of which about 2,000 belong to the Indus subspecies. However, the underlying surveys are temporally pathcy and believed to contain a large amount of uncertainty. Current population trends are unclear. A demonstrable increase in the main river population of the Indus subspecies between 1974 and 2008 may have been driven by permanent immigration from upstream tributaries, where the species no longer occurs.[2]

International trade is prohibited by the listing of the South Asian river dolphin on Appendix I of the Convention on International Trade in Endangered Species (CITES).[23] It is protected under the Indian Wildlife Act, although these legislations require stricter enforcement.[18] Both subspecies are listed by the IUCN as endangered on their Red List of Threatened Species.[2] The Indus river dolphin is listed as endangered by the US government National Marine Fisheries Service under the Endangered Species Act.

The species is listed on Appendix I[24] and Appendix II[24] of the Convention on the Conservation of Migratory Species of Wild Animals (CMS).

The Ministry of Environment and Forest declared the Gangetic dolphin the national aquatic animal of India. A stretch of the Ganges River between Sultanganj and Kahlgaon in Bihar has been declared a dolphin sanctuary and named Vikramshila Gangetic Dolphin Sanctuary (VGDS), the first such protected area.

The Uttar Pradesh government in India is propagating ancient Hindu texts in hopes of raising the community support to save the dolphins from disappearing. One of the lines being versed from Valimiki’s Ramayan, highlighted the force by which the Ganges emerged from Lord Shivji’s locks and along with this force came many species such as animals, fish and the Shishumaar—the dolphin.[25]

Human interaction

See also: Pollution of the Ganges and 2014 oil spill on Sundarbans
Gangetic dolphin, 1894 book illustration

Both subspecies have been very adversely affected by human use of the river systems in the subcontinent. Entanglement in fishing nets can cause significant damage to local population numbers. Some individuals are still taken each year and their oil and meat used as a liniment, as an aphrodisiac, and as bait for catfish. Irrigation has lowered water levels throughout both subspecies' ranges. Poisoning of the water supply from industrial and agricultural chemicals may have also contributed to population decline. Perhaps the most significant issue is the building of more than 50 dams along many rivers, causing the segregation of populations and a narrowed gene pool in which dolphins can breed.[16] An immediate danger for the Ganges subspecies in National Chambal Sanctuary is the decrease in river depth and appearance of sand bars dividing the river course into smaller segments.[26]

Non-human personhood

On 20 May 2013 India’s Ministry of Environment and Forests declared dolphins ‘non-human persons’ and as such has forbidden their captivity for entertainment purposes; keeping dolphins in captivity must satisfy certain legal prerequisites.[27]

See also

References

This article incorporates text from the ARKive fact-file ""Ganges river dolphin"" under the Creative Commons Attribution-ShareAlike 3.0 Unported License and the GFDL.

  1. ^ "Platanista Wagler 1830 (toothed whale)". Fossilworks.
  2. ^ a b c d Smith, B.D.; Braulik, G.T. (2017). "Platanista gangetica". IUCN Red List of Threatened Species. 2017. IUCN: e.T41758A50383612. doi:10.2305/IUCN.UK.2017-3.RLTS.T41758A50383612.en. Retrieved 29 May 2018.
  3. ^ A. Rus Hoelzel. Marine mammal biology: an evolutionary approach. Wiley-Blackwell, 2002. p. 8. Retrieved 10 February 2011.
  4. ^ "Declaration of Gangetic Dolphin as National Aquatic Animal" (PDF). Government of India - Ministry of Environment, Forest and Climate Change. 10 May 2010. Retrieved 23 October 2016.
  5. ^ "The Official Web Gateway to Pakistan". www.pakistan.gov.pk. Archived from the original on 28 November 2016. Retrieved 23 October 2016. {{cite web}}: Unknown parameter |deadurl= ignored (|url-status= suggested) (help)
  6. ^ "Gangetic river dolphin to be city animal of Guwahati". The Times of India. 6 June 2016.
  7. ^ Kinze, C.C. (2000). "Rehabilitation of Platanista gangetica (Lebeck, 1801) as the valid scientific name of the Ganges dolphin". Zoologische Mededelingen. 74. National Museum of Natural History: 193–203.
  8. ^ Pilleri, G.; G. Marcuzzi; O. Pilleri (1982). "Speciation in the Platanistoidea, systematic, zoogeographical and ecological observations on recent species". Investigations on Cetacea. 14: 15–46. {{cite journal}}: Unknown parameter |last-author-amp= ignored (|name-list-style= suggested) (help)
  9. ^ "One Species or Two? Vicariance, Lineage Divergence and Low mtDNA Diversity in Geographically Isolated Populations of South Asian River Dolphin" (PDF). Journal of Mammalian Evolution. 22 (1). 2015. doi:10.1007/s10914-014-9265-6.
  10. ^ Rice, DW (1998). Marine mammals of the world: Systematics and distribution. Society for Marine Mammalogy. ISBN 978-1-891276-03-3.
  11. ^ "Susu, the blind purpoise ... in the Ganges River, blind porpoise of Asia". The New Book of Knowledge, Grolier Incorporated. 1977., page 451 [letter A] and page 568 [letter S].
  12. ^ a b c "South Asian river dolphin (Platanista gangetica)". EDGE. Retrieved 26 July 2011.
  13. ^ "Blind River Dolphin: First Side-Swimming Cetacean". Science. New Series. 166 (3911): 1408–1410. 12 December 1969.
  14. ^ Kasuya, T., 1972. Some information on the growth of the Ganges dolphin with a comment on the Indus dolphin. Sci. Rep. Whales Res. Inst., 24: 87-108
  15. ^ "Indus River Dolphin". WWF Pakistan.
  16. ^ a b Braulik, G. T. (2006). "Status assessment of the Indus river dolphin, Platanista minor minor, March–April 2001". Biological Conservation. 129: 579–590. doi:10.1016/j.biocon.2005.11.026.
  17. ^ Sanyal, Sanjeev (2012). Land of the Seven Rivers: A Brief History of India's Geography. Penguin.
  18. ^ a b c Boris Culik. "Platanista gangetica (Roxburgh, 1801)". CMS Report. Archived from the original on 11 June 2011. Retrieved 24 July 2011. {{cite web}}: Unknown parameter |deadurl= ignored (|url-status= suggested) (help)
  19. ^ Swinton, J.; W. Gomez; P. Myer. "Platanista gangetica". Animal Diversity Web. Retrieved 24 July 2011. {{cite web}}: Unknown parameter |last-author-amp= ignored (|name-list-style= suggested) (help)
  20. ^ a b "The Whale and Dolphin Conservation Society". Retrieved 24 July 2011.
  21. ^ "Indus River Dolphin (Platanista gangetica minor)". Dolphins-World. Retrieved 29 May 2018.
  22. ^ "Ganges River Dolphin (Platanista gangetica gangetica)". Dolphins-World. Retrieved 29 May 2018.
  23. ^ "CITES". CITES. Retrieved 24 July 2011.
  24. ^ a b "Appendix I and Appendix II Archived 11 June 2011 at the Wayback Machine" of the Convention on the Conservation of Migratory Species of Wild Animals (CMS). As amended by the Conference of the Parties in 1985, 1988, 1991, 1994, 1997, 1999, 2002, 2005 and 2008. Effective: 5 March 2009.
  25. ^ "How Hinduism Continues to Save Dolphins in India". The Chakra News.
  26. ^ Singh, L.A.K.; R.K. Sharma (1985). "Gangetic dolphin, Platanista gangetica: Observations on habits and distribution pattern in National Chambal Sanctuary". Journal of the Bombay Natural History Society. 82. Bombay Natural History Society: 648–653. Archived from the original (PDF) on 26 October 2009. {{cite journal}}: Unknown parameter |deadurl= ignored (|url-status= suggested) (help); Unknown parameter |lastauthoramp= ignored (|name-list-style= suggested) (help)
  27. ^ Gautama, Madhulika (16 June 2014). "Dolphins get their due". The Hindu. ISSN 0971-751X. Retrieved 27 November 2016.

Further reading

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