A Chinese white dolphin seen in the waters around Hong Kong.

Soon all of Hong Kong's dolphins will be dead

Updated 10:03 PM ET, Sun September 24, 2017

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Hong Kong (CNN)A near constant wind buffets the top deck of Boat 36826 as it patrols the seas north of Hong Kong's largest island, Lantau.

Sitting in a white plastic lawn chair, staring intently through a pair of large, black binoculars, Charlotte Lau pulls a multicolored scarf high over her face and zips up her grey hoodie.
Down a steep staircase in the boat's main cabin, her boss Taison Chang sorts through the supplies piled on seats and a wide, curved table -- maps and charts, a GPS tracker, snacks, waterproofs, two-expensive cameras with long lenses, and several bottles of suncream in defiance of the dreary skies overhead.
Next to Lau, holding a walkie-talkie and shivering in a blue t-shirt, Viena Mak writes on a clipboard as her co-worker says: "no sighting."
It's a phrase the trio are becoming depressingly used to. They work for the Hong Kong Dolphin Conservation Society (HKDCS), which sends researchers out almost every day, no matter the weather, to search the city's waters for an ever-shrinking population of dolphins.
Their relentless work matters, not just to keep a few individual animals alive, but as a test of whether Hong Kongers can have more of a say in how their city progresses, take a step back from the mega projects and uninhibited development that have characterized Hong Kong for decades, and act to preserve what made it special in the first place.
Charlotte Lau and Viena Mak from the Hong Kong Dolphin Conservation Society survey the waters near Lantau Island.

I. Ancient 'ruddy' residents

On a day in July 1637, British explorer and trader Peter Mundy sat at anchor aboard the ship "Planter," near what was then still the Portuguese colony of Macau.
Mundy -- who would go on to help introduce tea to the UK, forever changing British drinking habits and imperial priorities -- wrote in his diary, "the Porpoises here are as white as Milke, some of them Ruddy withall."
It was one of the first recorded mentions of the Chinese white dolphin, but would go largely unnoticed until another European, Swedish missionary and naturalist Pehr Osbeck wrote of "snow-white dolphins (which) tumbled about the ship" and suggested a scientific name for them: "delphinus chinensis."