Yangtze River fish stocks up 25.6% but still far from recovery

Fish stocks in the Yangtze River are up by 25.6% following the introduction of a 10-year fishing ban in 2021, China’s Ministry of Agriculture and Rural Affairs reports. Total stocks remain low, however, at just 36.8% of their historic highs.

The ban covers the river’s main stem, large lakes opening into it, major tributaries and parts of the Yangtze estuary. Scientific advice was that it takes three to four years for many of the river’s fish species to reach sexual maturity, so a decade allows two or three generations to breed. Fish stocks and biodiversity have begun to recover during the first three years of the ban, according to the ministry, though they remain far short of the historical highpoint. And while 15 additional species are now being monitored, “120 of the 443 species historically found in the river remain unmonitored”, an official said in a press statement.

The ministry also notes that the migration of the Yangtze’s tapertail anchovy now reaches Dongting Lake, as far upstream as this species was ever previously recorded. Migratory fish recovery is a controversial topic in the environmental community. Studies show that the extinction of the Chinese paddlefish, for example, was not solely due to overfishing, and that habitat fragmentation also played a significant role. The latter often results from major hydropower projects and similar large-scale works, so fishing bans on their own may not save threatened species. Experts have called for hydropower projects to include more fishways, enabling fish to proceed upstream. The first fishway on the main stem of the Yangtze (the Jinsha hydropower station fish passage) was commissioned in March 2021, but as yet no information is available for assessing its effectiveness.

Relatively mild marine disaster losses of 2.5 billion yuan in 2023

China suffered direct economic losses of nearly 2.51 billion yuan ($346 million) due to marine disasters in 2023, according to the 2023 Bulletin on Marine Disasters and Sea Level from the Ministry of Natural Resources.

Overall, 2023 was a relatively mild year for marine disasters in China, with economic losses around 44% of the average over the past 10 years, according to the bulletin, issued on 22 April.

The most destructive incidents involved storm surges and wave events, along with ecological hazards such as red tides and green tides.

Coastal sea levels were down by 22 mm compared with the year before, though they were still 72 mm higher than normal (defined as the 1993-2011 average). The general trend for sea levels around China remained upwards, as a consequence of climate change, and the rate of rise is increasing: from 3.5 mm per year since 1980, to 4 mm per year (compared with a global average of 3.4 mm per year) since 1993.

The bulletin also notes that four provinces experienced intensified coastal erosion in 2023 due to rising sea levels, with some areas suffering heavy seawater intrusion that reached several kilometres inland.

Bottom trawling dredges up more debate in Europe

Greece has promised to ban bottom trawling in all its marine protected areas, as debate over this fishing technique continues to rage. The Greek ban – unveiled at the Our Ocean meeting in Athens this month – came with a promise of two more marine parks. The government said banning bottom trawling was “the single most effective measure for the preservation of marine biodiversity, the restoration of marine ecosystems and the promotion of sustainable fishing practices”.

On the other side of Europe, the French government is taking the United Kingdom to court over the latter’s move to ban bottom trawling in protected areas in La Manche / the English Channel.

“A diplomatic showdown must be launched immediately. The survival of an entire profession depends on it,” the Financial Times reports a branch of France’s Rassemblement National saying.