Why do the Chinese White Dolphins are endangered?? 10Marks!

1. Risks facing the dolphins

Loss of home:

Over the past decade, the home range of dolphins in Hong Kong has shrunk substantially because of the construction of the new airport at Chek Lap Kok Island and the associated land reclamation. The accumulative detrimental effects coastal development projects have on the dolphins is significant. Reclamation devastates coastal and benthic ecology, reduces the amount of fish available to the dolphins to feed on.

Dredging worsens water quality:

The dredging may also unearth pollutants that have settled on the seafloor causing water quality to further deteriorate. Now that a number of coastal and marine projects, including the well-known Hong Kong-Zhuhai-Macau Bridge and Container Terminal No. 10, are planned, it is worrying that our dolphins will have to continue to cope with all sorts of threats in the future.

Vessel collision :

Hong Kong is a busy harbour with numerous vessels travelling to and fro. North-western and Southern Lantau waters, the home of Chinese white dolphins, are no exceptions. High-speed ferry is by far the biggest threats to dolphins. Urmston Road waterway next to Sha Chau and Lung Kwu Chau Marine Parks is a main route connecting Hong Kong and Nansha of Mainland China. And the waterway south of Lantau Island is the major route for high-speed ferries travelling between Hong Kong and Macau. Dolphins frequent both of these waterways and researchers have witnessed many times how the ferries came close to striking dolphins. We have found some dolphins bearing scars likely to have been caused by vessel propellers. These were lucky to survive, but our guess is that others would have been less fortunate and were killed.

Dolphin watching boat disturbance:

Ecotourism has become more popular in Hong Kong in recent years. More and more tour companies, green groups and schools are holding Chinese white dolphin watching tours.

Allowing people to see and appreciate wild dolphins at sea is a good thing but because the activity is not regulated in any way, any type of boats can take visitors out and sometimes they disrupt the dolphins. For example, many dolphin-watching boats chase after the dolphins when they appear and sometimes several boats would encircle one pod of dolphins at once. Research shows dolphins stay away from these irresponsible boats, or choose to dive for longer. In the long term, the dolphins may abandon the area where they have been harassed.

In the last few years, dolphin watching operators have appeared around Tai O. Knowing nothing about dolphins, the skippers of these boats have been chasing the animals at even higher speeds than the other operators. It is likely that the greater the speed the boats chase the dolphins at, the great threat they pose to the dolphins.

Water pollution:

There is still no concrete proof that water pollution impinges directly on dolphins' health. Yet samples collected from dolphin carcasses in Hong Kong reveal high concentrations of organochlorine and heavy metals suggesting that these pollutants are harmful. ..........................................................

Too much words, please visit the following link:

http://www.hkdcs.org/QnA/HKdolp_cwd_en.htm#bm_cwdthrt