Chinese white dolphin

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Not to be confused with the Baiji (Chinese River Dolphin).
Chinese white dolphin
Pink Dolphin.JPG
Conservation status
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Cetacea
Family: Delphinidae
Genus: Sousa
Species: S. chinensis
Binomial name
Sousa chinensis
(Osbeck, 1765)
Cetacea range map Pacific Humpback Dolphin.PNG
Chinese white dolphin range (blue area)
Tail with visible grey and pink colours

The Chinese white dolphin or Indo-Pacific humpback dolphin (Sousa chinensis; Chinese: 中華白海豚; pinyin: Zhōnghuá bái hǎitún)[2] is a humpback dolphin species. An adult is white or pink and may appear as an albino dolphin to some. Uniquely, the population along the Chinese coast has pink skin,[3] and the pink colour originates not from a pigment, but from blood vessels which were overdeveloped for thermoregulation. The body length is 2 to 3.5 m (6 ft 7 in to 11 ft 6 in) for adults 1 m (3 ft 3 in) for infants. An adult weighs 150 to 230 kg (330 to 510 lb). Chinese white dolphins live up to 40 years, as determined by the analysis of their teeth.

These dolphins inhabit the waters of Southeast Asia and breed from South Africa to Australia. There are two subspecies, with Sumatra, one of the Indonesian islands, as the dividing line between the Chinese and the Western subspecies, Sousa chinensis plumbea. The two subspecies differ in color and dorsal fin size. The subspecies found in Southeast Asia has pinkish white skin and a larger dorsal fin, but lacks the fatty hump of South African and Australian relations.



Chinese white dolphins rise to the water surface to breathe for 20 to 30 seconds and after that, they will dive into deep water again. A calf dolphin surfaces from the water twice as much as an adult, because calves have smaller lung capacities than adults. Adult dolphins can stay underwater for about two to eight minutes, but a calf can only stay underwater for one to three minutes. Adult dolphins rarely stay under water for more than four minutes. They sometimes leap completely out of the water. They may also rise up vertically from the water, exposing the dorsal half of their bodies. A pair of protruding eyes allows them to see clearly in both air and water.

Reproductive cycle[edit]


Humans and the environment[edit]


Dolphin watching[edit]


There have been some recent reports of dolphin watching practices that have further endangered the Chinese white dolphins, such as in Sanniang Bay in Qinzhou[5][6] and off Xiamen.[7] However, these generally are small, locally organised one-off tours or private pleasure boats that do not adhere to the Hong Kong Agricultural and Fisheries Department's voluntary code of conduct. The basic principles of these codes of conduct are to always observe the dolphins from a distance, and to not attempt to physically contact, feed or harm the dolphins. Additionally, boats should maintain a slow and steady speed, not exceeding 10 knots, and the boat should always maintain a parallel movement to the dolphin's course.[8]

Cantonese slang[edit]


Eastern Taiwan Strait (ETS) population[edit]

The Indo-Pacific humpback dolphins were first discovered along the west coast of Taiwan in 2002. Based on a survey done in 2002 and 2003, they are often found in waters <5m deep, and no evidence shows that they appear in water deeper than 15m.[9] A study in 2008 found that the population of humpback dolphins, which occupies a linear range of about 500 km^2 along the central west coast of Taiwan, is genetically distinct from all populations living in other areas.[10] And this population is called eastern Taiwan Strait (ETS) population.

Taiwan is a densely populated island and highly developed country, which has many industrial development projects, especially along the west coast, where the ETS populations of Indo-Pacific humpback dolphins live. Based on data collected between 2002 and 2005, the ETS population of humpback dolphins was less than 100 individuals.[9] Unfortunately, the newest data released in 2012 shows that only 62 individuals are left. It means during those 7 years, population of humpback dolphins is being destroyed constantly and severely. A preliminary examination revealed that the ETS humpback dolphin population meets the IUCN Red List criteria for “Critically Endangered”.[11] Without further protection and regulation, this population will go extinct quickly.

There are several facts that result in the decreasing number of ETS population of humpback dolphins. First, large-scale modification of the shoreline by industrial development including hydraulic filling for creating industrial or science parks, seawall construction and sand mining cause habitat fragmentation and diminish dolphin’s habitats. In addition, exploitation of shoreline also contributes to toxic contamination flows into dolphin’s habitats. The chemical pollution from industrial or agricultural and municipal discharge results in impaired health of dolphins, for instance, reproductive disorders, and compromised immune system.[12]






The Indo-Pacific humpback dolphin is listed on Appendix II[13] of the Convention on the Conservation of Migratory Species of Wild Animals (CMS). It is listed on Appendix II[13] as it has an unfavourable conservation status or would benefit significantly from international co-operation organised by tailored agreements. In the interim of 2003–2013, the number of these dolphins in the bay around Hong Kong has dwindled from a population of 159 to just 61 individuals, a population decline of 60% in the last decade. the population continues to be further threatened by pollution, vessel collision, overfishing, and underwater noise pollution.[14]


Timeline of main events[edit]

  • 1637: The Chinese white dolphin was first discovered in Hong Kong by the adventurer Peter Mundy near the Pearl River. The species are attracted to the Pearl River Estuary because of its brackish waters.
  • 1765: Pehr Osbeck gives the first scientific description of the species.[15]
  • 2014: Dr. Thomas Jefferson and Dr. Howard C. Rosenbaum revise the taxonomy of the humpback dolphins (Sousa spp.). They describe a new species, the Australian humpback dolphin and define the accepted common name for this species, the Indo-Pacific Humpback dolphin. [16]

See also[edit]


  1. ^ Reeves, R.R., Dalebout, M.L., Jefferson, T.A., Karczmarski, L., Laidre, K., O’Corry-Crowe, G., Rojas-Bracho, L., Secchi, E.R., Slooten, E., Smith, B.D., Wang, J.Y. & Zhou, K. (2008). Sousa chinensis. In: IUCN 2008. IUCN Red List of Threatened Species. Retrieved 24 March 2009.
  2. ^ "Sousa chinensis" in Mammal Species of the World.
  6. ^ Show China. Retrieved on 2014-05-15.
  16. ^ Jefferson and Rosenbaum (2014) Taxonomic revision of the humpback dolphins (Sousa spp.), and description of a new species from Australia.

External links[edit]