The Chinese White Dolphin (Sousa chinensis)Introduction
Chinese White Dolphins are a Cetacean species. In
Southeast Asia, they are born with a black colour, they quickly change to grey and
gradually become white or pink. Chinese White Dolphins are found near coastlines, and
usually near the mouth of major rivers .The Pearl River near Hong Kong provides the
estuarine water which is comfortable for them. This population is usually found to the
north of Lantau Island and occasionally to the southwest, near the Soko Islands, and
the southeast, near Peng Chau. Population estimates range from fewer than 100 to around
150. Current studies are limited to Hong Kong Territorial waters, because Chinese
Authorities do not allow their water to be surveyed, so these estimates do not consider
the total population in the Pearl River Delta.
Behaviour:
Chinese White Dolphin can talk naturally to their
friends. They can bend the upper part of their body forward, slap, do head bobbing, swim
at a high speed and breach. As they grow up, they may develop a high level of movement
such as somersaulting. Those that we can see in a dolphin show are advanced ones. They can
do ball jumping, object pushing and finding an object then bringing it back.

Habitat and Distribution:
They require shallow, sheltered, estuarine waters.
Chinese White Dolphins are usually distributed in coastal areas of the Atlantic Indian and
South Pacific Oceans and the tropical sea of SE Asia. Places such as the Pearl River Delta
are the most suitable for them. They are usually seen around the rocky, reef seabed island
areas, mentioned above, where their prey occurs.
Threats
The Chinese White Dolphins were sighted 120 times in 1996 which is a low number. All
calves born in 1996 have died. The reason for this is because the project of the Chek Lap
Kok New Airport in Lantau Island. It is also because the building of the Tung Chung New
Town, North Lantau Expressway and the Tsing Ma Suspension Bridge. Water in these
construction areas are murky due to the fact that is too close to the Pearl River delta.
The construction causes extra reclamation silt and the water turns completely brown. They
also die because of the explosions and heavy boat traffic. These two factors produce high
noise level and polluted air. Humans have treated the Chinese White Dolphin cruelly
causing problems such as: loss of habitat. People have reclaimed land in Kowloon and dug
mud from the seabed. It has polluted the water and destroyed the environment. Also,
over-fishing has caused a reduction in food supplies. Finally, the construction of
the new airport and the increase in traffic between China and Hong Kong causes noise
pollution which affects dolphin's ability to communicate and find the direction.
Toxic material, chemical waste, bacteria and viruses have killed a lot of marine life.
Also, some sewage, which has not yet been treated sometimes flows into the sea. Oil also
sometimes flows into the sea and causes damage to their lung tissues. People hunt dolphins
for their blubber, baleen and the substances used for producing perfumes and perhaps
just for fun. Although fishermen do not wish to kill the dolphins, many of them are
trapped in fishing nets and are choked to death or drowned accidentally. Predators of the
sea such as sharks and large sea animals often kill and eat dolphins.
Protection Efforts
We should save the dolphins by
1) Giving places free from marine traffic for them to rest, nurse the young and find food.
Inside areas should have a limit of speed, sounds and make sure ships don't come into the
marine parks.
2) Make sure there are enough food in the marine park, fishing and dredging should not be
allowed. Fishing is only allowed at the places where it doesn't disturb the dolphins.
Young fish and prawns should be protected for the basic food of the dolphins.
3) Treat the sewage properly, don't use DDT, PCB and stop pumping contaminated sludge in
the sea to keep the ocean clean.
4) Use double hull tankers to make sure no oil is spilled out
5) Fishing practices need to be revised to make sure there is no trawling in coastal
waters.
6) Education should be given to the people, teaching them to reduce waste production,
recycle useless products, don't throw plastic products in wrong places.

Information researched from the
following sources:
Hong Kong Dolphin Watch (dolphins@hk.super.net)
WWF Hong Kong Factsheets - The Chinese White Dolphin - Sousa chinensis. 1994,
1997 WWF HK.
Hong Kong Institute of Education: www.crucial.ied.edu.hk
www.user.hk.linkage.net/~pulle/pint.htm
Contributors:
Class F3-147 |
Dutch translation follows asap Nederlandse vertaling volgt
zo spoedig mogelijk. |
Written by (geschreven door):
Helen Cheng, Duncan Cheung, Gary Law, Vinci Lee,
Kenneth Leung, Jerome So, Candy Tong, Jason Wan, Anita Nga |