Hong Kong's Rare Pink Dolphins at Higher Risk of Disappearing

The pink dolphins of Hong Kong are commonly known as the Indo-Pacific Humpback Dolphins, or Chinese White Dolphins. These species are already vulnerable, and now at even higher risk due to reclamation projects in Hong Kong.

These pink dolphins (Sousa Chinensis) are similar to bottlenose dolphins in terms of size. They are born black, and they change color to grey and then white as they grow older. Frequently, these dolphins appear a bright shade of pink. This color is attributed to the blood vessels found close to the animal's skin to help it stay cool.

These dolphins keep warm in colder ocean waters. However, in warm tropical waters, they need to lose heat. Their cooling mechanism functions through passing the blood through their blood vessels, particularly during hot weather.

Currently, the Chinese white dolphin is listed as one of the species with unfavorable conservation status. During the late 90s, their population was only around 200, and currently, their numbers have plummeted even further.

As of 2019, Ocean Park, a marine park owned by the Hong Kong government has found a total of six dead pink dolphins, and two of the deaths were near the reclamation site of a third runway. This figure accounts for only thirty-two (32) individuals left.

Hong Kong's pink dolphins are not migratory and tend to stay within inshore waters, often limiting themselves to a meager area of 100 square kilometers. This habit makes them especially vulnerable to human activities that happen around Hong Kong waters.

As one of the busiest ports in the world, Hong Kong has a lot of sea and seaport-related activities that endanger the population of the pink dolphins. The shrinking number of dolphins along the Chinese coast is due to enormous reclamation and infrastructure projects around the dolphins' marine habitat. The surrounding waters become so bustling with human activities that it becomes polluted and dangerous.

Mr. Taison Chang, chairman of the Hong Kong Dolphin Conservation Society, categorizes the threat into four: coastal development and reclamations, marine traffic, water pollution, and fishing.

Dolphin WL212 is an example of the tragic effect of marine traffic on the dolphins. In 2015, the dolphin was found with deep cuts that its tail was almost severed. It was presumed to have been hit by the blades of a boat turbine. The young male dolphin was only six years old.

Mr. Chang and his team observed the dolphin for three weeks. It was trying its best to survive and feed itself despite its injuries. After a media outcry, Ocean Park captured the dolphin for treatment. Unfortunately, the dolphin died from its injuries after four days in captivity.

The Airport Authority claims that with the third airport well on its way, it has been observing precautions to protect the dolphins. They keep speed limits for high-speed ferries, and they try to avoid percussive piling during construction. However, these are not the only battles the dolphins are facing. Contaminants in Hong Kong waters have also been found in high concentrations in the tissues of these pink dolphins and poses a considerable concern for their already-dwindling population.