On a recent visit to Hong Kong, I made some time to go and see the near threatened Chinese White Dolphin (Sousa chinensis) which is the local name of the Indo-Pacific Humpback species, also known in Hong Kong as the Pink Dolphin, due to their unique colour. There are currently only 50 left in Hong Kong, with a rapid death rate of 10 per year. The pink dolphins will very sadly disappear completely if the government choose to do nothing to protect them.
The Hong Kong Dolphinwatch has been running trips in Hong Kong for 21 years and strictly adhere to the code of conduct to run their dolphin watching activities which are to always observe the dolphins from a distance, to not attempt to physically contact, feed or harm the dolphins. Additionally, boats must maintain a slow and steady speed, not exceed 10 knots, and maintain a parallel movement to the dolphin’s course. They put maximum efforts into raising dolphin awareness especially amongst the Hong Kong residents. The dolphins mainly live in the waters of Lantau North, Southeast Lantau, the Soko Islands and Peng Chau, but are mostly seen north of Lantau and around the Soko Islands.
The dolphins are born a very dark grey and it’s only after a few months that the babies start to fade to a light grey. Within the next few years, the grey begins to turn to pink or white, leaving grey spots behind that eventually disappear when the dolphins get older. The pink colour is not from a pigment, but from blood vessels that overdevelop by thermoregulation, which is the blood flushing to the outer layers of the skin, regulating the body temperature.
With so few of them known to be around, I was surprised to see them come so close to the boat and to see as many as we did in that area, it was very special. Although we saw no babies, we did see a couple of young, very light grey ones which enabled us to better understand the change of colour their skin goes through.
Babies are born about a metre long and stay with their mother until about 3 years old, during which time the mother will not have another baby. They give birth to only one baby at a time. Females reach sexual maturity around 10 years and males are thought to reach their sexual maturity at 13 years. Adults grow to 2.5-3 metres and life expectancy should reach 40 years except in Hong Kong where their lifespan is only expected to reach half of that due to the deterioration of the environment with all the new developments taking place.
There are so few left in the wild because of the destruction of habitat, over fishing, fishery by-catch, heavy sea traffic and pollution caused by the developments to the new airport extension, the Disneyland train station and the new 42km bridge being built to link Hong Kong, Macau and Zhuhai which sits right in the middle of the pink dolphins’ habitat in the Pearl River Delta. There is talk of a second bridge to be built to link the main bridge to Tuen Mun. With all the noise created from the construction work, dredging, reclamation, and the traffic of 20,000 vehicles expected to cross the bridge per day once finished, the dolphins’ echolocation is also greatly affected.
Sadly, the Hong Kong government is only interested in the new developments. If the dolphins are to survive, the governments in Hong Kong, Macau and China have to seriously address the pollution issues, fisheries management and marine conservation. The Dolphinwatch are encouraging people to write to the government and media, spread the message, support the research and check the “Save the Dolphins” page on their website.
Hong Kong Dolphinwatch Ltd.
1528A, Star House, Tsimshatsui, Kowloon, Hong Kong
Emial: info@hkdolphinwatch.com
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