(Platanista minor)
Overview
Very similar in appearance to the Ganges River dolphin (Platanista gangetica). These two species are the sole survivors of an ancient and diverse family of cetaceans. The Indus River dolphin is generally found alone or in small groups in the deepest channel of the Indus River. Its range has drastically decreased over the past century as a result of the construction of irrigation barrages (low, gated diversion dams), which have fragmented the population, and reduced available habitat by depleting the volume of water flowing downstream. Concerted conservation action is needed if this species is to survive.
Urgent Conservation Actions
Efforts to ensure the Sindh Dolphin Reserve population remains well-protected are crucial, as is the creation of additional areas of protected habitat.
Distribution
Restricted to less than 700 km of the Indus River, Pakistan.
Fact
Until the late Pliocene, the present-day Indus, Ganges and Brahmaputra (except for the upper reach, the Yarlung Zangpo Jiang) rivers constituted a single westward-flowing river called the Indobrahm. Even up until historical times there was probably sporadic faunal exchange between the Indus and Ganges drainages by way of head-stream capture on the low Indo-Gangetic plains, between the Sutlej (Indus) and Yamuna (Ganges) rivers (Rice 1998).
Associated Blog Posts
14th Jan 08
Conservationists are delighted over the recent sighting of six rare Indus River dolphins (Platanista minor) in northwestern India, an area that traditionally...  Read

Media from ARKive
ARKive image - Ganges river dolphin swimming
ARKive video - Ganges river dolphin breaching
ARKive image - Ganges river dolphin swimming at water surface
ARKive image - Ganges river dolphin diving at water surface
Evolutionary Distinctiveness
Order: Cetacea
Family: Platanistidae
Traditionally all river dolphins were grouped together into the family Platanistidae. However, genetic studies have shown that they represent a convergent group of only distantly related species, which are superficially similar to one another – for example, having reduced eyes - because they have each evolved in similar riverine environments. The ancestors of the Ganges and Indus River dolphins are now thought to have represent one of the earliest divergences within the odontocete (toothed whale) clade, after it separated from the mysticetes (baleen whales) during the Oligocene (30-35 million years ago). Indian river dolphins diverged after the Physeteridae (sperm whales) but before the divergence of the beaked whales, Chinese and South American river dolphins, marine dolphins and porpoises. The platanistid lineage was highly successful over the past 30 million years; it diversified into many different species, the fossils of which are known from marine sediments around the world. Today, the Ganges and Indus River dolphins are the sole survivors of this once diverse cetacean group.
Description
Size: 
Length: 1.5-2.5 m
Weight: 80-90 kg
A stocky freshwater dolphin characterised by a long beak that widens at the tip. The beak can reach up to a fifth of the dolphin’s body length, and contains large visible teeth. The dorsal fin is undeveloped compared to other dolphins and looks like a low triangular hump. Both the flippers and the flukes (tail fins) are large and broad. The colouration is dark grey or grey-brown above and lighter, occasionally pinkish below. The forehead is steep and rises abruptly from the base of the snout. The eyes lack lenses, leaving the species unable to resolve images; the most the dolphins can do is perceive the presence or absence of light. Females are generally larger than males and may have longer rostrums. There is very little difference in appearance between the Ganges and Indus River dolphins.
Ecology
Individuals spend most of their time feeding and travelling alone, although groups of up to 30 are sometimes seen in areas presumed to be good habitat. Fish and invertebrates are the main prey species. Most feeding takes place at or near the bottom, with the dolphin swimming on one side and probing the substrate with its beak or flipper. Individuals use echolocation to detect food and navigate, and – to a very small extent – for communication. It has been suggested that before barrages restricted their movements, the dolphins migrated seasonally according to fluctuations in water levels. They are thought to have spent the dry season in deep pools or the main channels of the river systems, and then migrated upstream to the tributaries prior to the monsoon. Births may take place throughout the year, but appear to peak in December-January and March-May. A single calf is born every two years. Juveniles are weaned at around one year of age, but do not reach sexual maturity until around 10 years of age. This species is thought to live at least 28-30 years in the wild.
Habitat
This species is found in freshwater river systems. The dolphins generally occur in the deepest river channel and are less common in secondary channels. Reported habitat preferences include channel constrictions, confluences (where rivers or streams converge), and deep water.
Distribution
Formerly ranged throughout the 3,500 km Indus river system in Pakistan. Today the majority of the dolphins are restricted to less than 700 km of river. The majority of the remaining population is found in the mainstream between the Sukkur and Guddu barrages in Sind Province. There are two small additional subpopulations between the Chashma and Taunsa barrages and the Taunsa and Guddu barrages in Punjab and NWFP Provinces. A few individuals still remain above Chashma Barrage and below Sukkur Barrage.
Population Estimate
A 2001 survey resulted in a population estimate of approximately 1200 individuals.
Population Trend
Decreasing.
Status
Classified as Endangered (EN A2abcde; B1ab(i,ii,iii,iv); C1) on the 2006 IUCN Red List of Threatened Species.
Threats
The species is threatened primarily by the damming of rivers for irrigation and electricity generation, which degrades habitat, isolates populations and prevents seasonal migration. The construction of three irrigation barrages, completed at Sukkur in 1932, at Kotri in 1955, and at Guddu in 1969, has had a devastating effect on the species. They have severely fragmented the population and reduced the volume of water, particularly downstream of the Sukkur Barrage, causing the dolphins’ dry-season range to shrink. Subpopulations on either side of barrages are now isolated and thus are more vulnerable to extinction due to hunting or environmental change. It has been hypothesised that individuals may swim downstream through barrage gates during the wet season or during canal closure, but are unable to return due to strong downstream hydraulic forces within the barrage gates. Since the mid 1990s, there have been increasing reports of dolphins trapped in irrigation canals near Sukkur Barrage, many of which die when the canals are drained for annual de-silting and maintenance. Further declines are expected as more dams are planned upstream of the dolphins range, and increasing demands for water in Pakistan will likely further deplete dry season river flows. Other threats include accidental entanglement in fishing nets and entrapment in irrigation canals.
Conservation Underway
The species is legally protected throughout its range and is listed on Appendix I of CITES. The area between the Sukkur and Guddu Barrages was declared a dolphin reserve in 1974 (the Sindh Dolphin Reserve), and dolphin counts here show an apparently increasing trend from 1975 to 2001. Two additional sanctuaries, the Taunsa Wildlife Sanctuary (est. 1983) and the Chashma Wildlife Sanctuary (est. 1984) in Punjab Province also appear to be helping to arrest the rapid population declines. A programme sponsored by the United Nations Development Programme (UNDP) to rescue dolphins trapped in irrigation canals and return them to the Indus mainstream has had some success in reducing mortality.
Projects
Conservation Proposed
Efforts to ensure the Sindh Dolphin Reserve population remains well-protected are crucial, as is the creation of additional areas of protected habitat upstream of the Guddu Barrage. The International Whaling Committee (IWC) recommends that priority be given to monitoring the survival and movement of dolphins rescued from irrigation channels. Surveys should also be carried out to assess the current distribution and abundance of the species, and to assess the availability of suitable habitat. Further research into the main threats facing the species is required in order to implement effective conservation measures. In particular, the effects of barrages and canal gates on dolphin movements need to be determined. Finally, education and public awareness programmes are crucial to conservation efforts as many local people are unaware of the dolphin’s protected status and regulations.
Associated EDGE Community members

Gill is an expert on river dolphins in Asia

Links

The Ministry of Environment’s Pakistan Wetlands Programme aims to promote the sustainable conservation of freshwater and marine wetlands and their associated globally important biodiversity in Pakistan. A key objective of the programme is to ensure that wetlands biodiversity is sustainably conserved in the Central Indus Wetlands Complex (CIWC) by designing and implementing a comprehensive Management Plan.
Key Contacts: Richard Garstang & Gill Braulik
Address: Pakistan Wetlands Programme/ House 3/ Street 4/ Sector F7/3/ Islamabad/ Pakistan/ +92 51 261 0880/5
Project Dates: 2006-2012

WWF
WWF – Conservation of the Endangered Indus River Dolphin WWF International and WWF Pakistan are currently working to conserve the Indus river dolphin in Pakistan as part of a larger regional initiative to conserve river dolphins and freshwater ecosystems.

Key contact: Uzma Khan
Address: WWF-Pakistan / PO Box 5180 Lahore 54600 / Pakistan / +92 42 5862360
Project dates: 1, Jan 2000 - 30, Jun 2007

Whale and Dolphin Conservation Society (WDCS)
This informative site provides background information on the Indus River dolphin and highlights conservation efforts for this species.
References
Braulik, G.T., 2006. Status assessment of the Indus River dolphin, Platanista gangetica minor, March-April 2001. Biological Conservation, 129: 579-590.

Convention on Migratory Species (CMS): Platanista gangetica, Ganges river dolphin

Nikaido, M., Matsuno, F., Hamilton, H., Brownell, R. L. Jr, Cao, Y., Ding, W., Zuoyani, Z., Shedlock, A. M., Fordyce, R. E., Hasegawa, M. and Okada, N. 2001. Retroposon analysis of major cetacean lineages: The monophyly of toothed whales and the paraphyly of river dolphins. Proceedings of the National Academy of Sciences of the United States of America 98(13): 7384-7389.

Nowak, R. M. 1999. Walker’s Mammals of the World. Sixth edition. The Johns Hopkins University Press, Baltimore and London.

Reeves, R. R., Smith, B. D., Crespo, E. A. and Notarbartolo di Sciara, G. 2003. Dolphins, Whales and Porpoises: 2002-2010 Conservation Action Plan for the World’s Cetaceans. IUCN: Gland, Switzerland.

Smith, B.D. & Braulik, G.T. 2004. Platanista gangetica. In: IUCN 2006. 2006 IUCN Red List of Threatened Species. Downloaded on 23 July 2006.

Distribution map based on data provided by the IUCN Global Mammal Assessment.

if you can provide new information to update this species account or to correct any errors, please email us at info@edgeofexistence.org


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