In January 2021, China did something almost without precedent in modern industrial history.
It shut down commercial fishing along the entire length of the Yangtze River — the world's third-longest river, 6,300 kilometres from the Tibetan Plateau to the sea — for a decade. Not a partial restriction. Not a seasonal closure. A total ban. Across the main stem, major tributaries, and connected lakes.
At the time, the river was collapsing. Fish populations had declined by over 70% since the 1950s. Pollution, dams, sand mining, overfishing, and habitat destruction had hollowed out what was once one of the most biodiverse freshwater ecosystems on Earth. The Yangtze river dolphin — the baiji — was already functionally extinct. The Yangtze finless porpoise, the river's last surviving freshwater mammal, was spiralling toward the same fate with just 445 individuals remaining.
Five years on, a new study published in the journal Science in February 2026 has revealed what happened next.
The results are extraordinary.
Fish biomass in the Yangtze has increased by 209% compared to pre-ban levels. Species richness rose by 13%. Larger-bodied fish species — the ones most sensitive to fishing pressure — showed the biggest comeback, with biomass gains of 232%. Between 2021 and 2025, 351 fish species were recorded in the basin — 43 more species than before the ban. The Chinese high fin banded shark — not seen reproducing naturally for over 20 years — was recorded spawning again in 2024 and 2025.
And the porpoises?
From 445 individuals in 2017, the Yangtze finless porpoise population rose to 595 in 2022. By 2025, it had surged to 1,426 — a 220% increase from the low point, and more than three times what it was eight years ago. Chinese authorities have set a target of 1,700 by 2030 and 2,000 by 2035.
The mechanism is almost beautifully simple: when you stop killing fish, fish come back. And when fish come back, the porpoises that depend on them come back too. With more food, less entanglement in fishing gear, and quieter waters, the river's ecosystem is beginning to breathe again.
The Chinese government invested over US$2.7 billion to resettle more than 231,000 fishers and decommission over 111,000 fishing vessels — a relocation programme on a scale rarely attempted anywhere in the world. Fishers were given retraining, new livelihoods, and compensation. The political will required to make this happen was immense.
The Guardian's reporting calls it 'a model for large-scale, politically driven conservation initiatives globally.'
Challenges remain. Illegal fishing continues. Industrial pollution from factories still enters the river. The impact of major hydropower dams — which block migratory species like the critically endangered Chinese sturgeon from reaching their spawning grounds — is real and ongoing. The restoration is not complete.
But the direction of travel is unmistakable.
The Yangtze is healing. The fish are coming back. The porpoises are multiplying. And five years into a ten-year experiment in letting nature recover, the data says: it's working.
Sometimes the most powerful thing we can do for nature is simply step back. 🐬