Ancient Chinese poems tell the story of how the charismatic river porpoise declined over the past 1,400 years

A close-up of a "smiling" Yangtze finless porpoise at the Baiji Dolphinarium of the Institute of Hydrobiology, Chinese Academy of Sciences. (Image Credit: Wang Chaoqun)

A creature once revered in ancient Chinese folklore and immortalized in poetry for its playful spirit and perpetual smile is now swimming against extinction. The Yangtze finless porpoise—Asia’s only freshwater porpoise—has lost over 65% of its habitat range in the past 1,400 years, with most of that decline occurring in just the last century, according to a groundbreaking study published May 5 in Current Biology.

But the revelation didn’t come from satellite imagery or sonar scans—it came from the verses of 724 ancient Chinese poems.

In a rare fusion of art and science, researchers from the Chinese Academy of Sciences, led by conservationist Zhigang Mei, sifted through centuries of classical literature to track the historical presence of the porpoise. The poems, dating as far back as the Tang Dynasty (618–907 CE), were drawn from across China and carefully analysed for clues about the animal’s former range.

“We’re connecting 2,000 years of Chinese culture with biodiversity,” says Mei, who grew up along the Yangtze River listening to village elders speak of the porpoises as weather-predicting spirits. “Our work fills the gap between fossil records and recent population surveys. It really shows how powerful it can be to combine art and biodiversity conservation.”

Once widespread throughout the 6,300-kilometre Yangtze and its tributaries, the porpoise is now largely confined to limited stretches of the main river. According to the study, the species’ range in the main river has shrunk by 33% since the Tang era. But the more startling figure comes from the tributaries and lakes, where habitat loss is as high as 91%.

The team’s poetic deep dive uncovered a pattern: the number of references to the porpoise peaked during the Qing Dynasty (1636–1912), with 477 poems, before plummeting in modern times. “Porpoises were often described chasing fish or leaping before storms—scenes too vivid for poets to ignore,” Mei explains.

To ensure accuracy, the researchers cross-referenced each poem with historical records, examining the poet’s life, geographical movements, and writing style. This allowed them to construct a timeline of sightings and habitat shifts with surprising precision.

The findings reinforce what modern ecological studies have long warned: hydraulic engineering—particularly dam constructions in the 1950s—has severed connections between the river and its wetlands, effectively choking off the porpoise’s access to vital feeding and breeding grounds. Similar changes likely led to the functional extinction of other Yangtze natives like the baiji dolphin and Chinese paddlefish.

But the study offers more than grim statistics—it offers a cultural lens for conservation. “Protecting nature isn’t just the responsibility of modern science; it’s deeply rooted in our history,” Mei says. “Art, like poetry, can help people feel the harmony that once existed between humans and nature.”

Looking ahead, the team hopes to use their poetic archive to uncover even more ecological insights—how the river once flowed, what the porpoise populations looked like, and how their behaviour may have changed over time.

For Mei, this project isn’t just about tracking an endangered species—it’s about bridging past and present. “Chinese poetry, this ancient art form, can be a serious scientific tool,” he says. “It’s not just research—it’s a conversation with the poets of the past.”