Are Hong Kong’s pink dolphins about to disappear?

Hong Kong’s pink dolphins are actually Indo-Pacific Humpback Dolphins, or Chinese White Dolphins. And their skin isn’t pink; the animals live in murky waters with little sun penetration so it simply lacks pigmentation. It is warm blood pumping through vessels close to the skin’s surface that gives the dolphins their bubblegum pink appearance.

The first recorded mention of these unusual creatures was by a British man called Peter Mundy in 1637. Mundy, a merchant who helped introduce tea to the UK, described the dolphins as "sword fish", not realising they were mammals. He wrote in his journal: “The porpoises here are as white as milk, some of them ruddy withal.”

Hong Kong’s fishermen have known about the creatures for centuries. They call the dolphins Hak Kei (the Black Taboo) or Pak Kei (the White Taboo). "Once they are here, all the fishes will be gone!" says Uncle Wai, a fisherman in Tai O, a major fishing village in the western edge of the territory.

Catching a glimpse is not easy but dolphin-watching tours have become popular with tourists. When people see the dolphins for the first time, their joy is obvious.

“I’ve had some striking moments,” says Janet Walker, a senior guide with the DolphinWatch tour. "You know, amazing aerial displays and things… or like the dolphins that come and swim under your feet! Or, you know, look you in the eye.”

But Janet is worried. She’s noticed the dolphins are disappearing. "You know we are still seeing a few calves, but not that many, and the number’s still plummeting."

Outside of the tourism and fishing industries, pink dolphins aren’t a part of daily life for the 7.4 million people that live in the dense and bustling port of Hong Kong.

"To be frank, like many Hong Kongers, I knew little about the dolphins until I picked up this job,” says Taison Chang, chairman of the Hong Kong Dolphin Conservation Society.

"And that's the problem. Many of us were aware of them, but all we knew was the superficial stuff. We need to know about the problems they are facing before we can conserve them.”

In 2017, the population looked like it was low but stabilising. When the latest figure of 32 dolphins was released last summer, a 32% drop on the 2017-2018 period, it was a shock to conservationists like Mr Chang.

Chinese White Dolphins can be found off the west coast of Taiwan, as well as Vietnam, Thailand, and as far as Java in Indonesia in the South, and Tamil Nadu in India in the West, according to the International Union for Conservation of Nature (IUCN). While this explains why the species as a whole is not yet classified as endangered, what is clear is that their habitat along the Chinese coast has been rapidly shrinking as huge infrastructure projects reclaim marine habitat and the surrounding water becomes busy and polluted. Populations like the one in Hong Kong could disappear within a generation.

The story of dolphin WL212 is a tragic example of the threat dense marine traffic poses to the pink dolphins. In 2015, it was found with cuts so deep that its tail was almost severed. It was thought the young six-year-old male was hit by the blades of a boat turbine.

Hong Kong is one of the busiest ports in the world. For the pink dolphins not only is there less space but the habitat available to them is crisscrossed 24 hours a day with thousands of boats.

Taison Chang worked with Daphne Wong, a Hong Kong-born filmmaker, to document what happened to the dolphins. He provided her with video records of Dolphin WL212's final days.

"Back then our team kept tracking it for three weeks. We saw it doing its best to survive despite those heavy injuries, to feed itself," Mr Chang recalls.

After a media outcry, Ocean Park, a marine park owned by the government, captured the struggling dolphin for treatment. They named him Hope. But after four days in captivity, Hope died from his injuries.

The incident left a lasting impression on Mr Chang.

"I’ve been thinking, why was this dolphin hurt so badly? Have we done something wrong? I’ve been thinking a lot about this. How could we protect them? Conserve them?"

“I was editing the film and I was about to cry,” said Daphne.

The Hong Kong-Zhuhai-Macao Bridge Authority, an agency jointly set up by Hong Kong, Macau and Guangdong province governments to build and manage the bridge, claims 945 Chinese White Dolphins lived in Hong Kong and the wider Pearl River Estuary in the 2017-2018 period.

But Angel Lam, an Oceans Conservation Manager with WWF-Hong Kong, says they’ve been unable to secure a copy of the full report to assess its reliability.

"It’s hard for academics up there to carry out their work. Would the government ever let them tell the true, downward figures?" questions Taison Chang.

The BBC asked the Bridge Authority for a copy of the report but they refused to release it.

"There’s very much an attitude of 'the dolphins will go somewhere else!' They can’t!” says Janet Walker of DolphinWatch.

"They don’t have anywhere else to go. And I don’t think many people appreciate or understand that."

For the dolphins, water to the north lacks salinity and water to the south is too salty.

"Because of what they eat, they are stuck in the area where freshwater meets sea water, and so that means river estuaries," explains Mr Chang. "They would not leave river estuaries for the open water. It’s the same for all humpback dolphins around the world."