China’s Yangtze fish-rescue plan is a failure, study says
研究称，中国长江鱼类救援计划失败
Five fish species, including the iconic Chinese sturgeon, have gone extinct, or will soon be extinct, because of dams on the Yangtze River in China, according to a paper released on 10 May in Science Advances1. The findings have reignited a long-running debate among Chinese scientists about the best way to rescue the species in the Yangtze, with some saying that the analysis is flawed.
5月10日发表在《科学进展》杂志上的一篇论文称，由于中国长江上的大坝，包括标志性的中华鲟在内的五种鱼类已经灭绝，或即将灭绝。这些发现重新引发了中国科学家之间关于拯救长江物种的最佳方法的长期争论，一些人说分析是有缺陷的。
The Yangtze River is a mighty 6,300-kilometre-long waterway and a global biodiversity hotspot that runs through 11 Chinese provinces. But over the past 50 years, six major hydropower dams and more than 24,000 smaller hydropower stations have been built in the river’s main stream and branches — with even more on the drawing board.
长江是一条长达6300公里的强大水道，也是全球生物多样性热点，流经中国11个省。但在过去的50年里，六座大型水电站大坝和24000多座小型水电站已经在河流的干流和支流上建成，还有更多的水电站正在规划中。
The dams were built to help generate electricity, provide flood protection and make the river easier to navigate. But dams can block migratory fishes and damage their habitat. To mitigate the effects of the dams, fish-rescue programmes have been in place in various forms since 1982, when the first dam was being constructed.
这些大坝的建造是为了发电，防洪，使河流更容易航行。但是大坝会阻挡洄游鱼类，破坏它们的栖息地。为了减轻水坝的影响，自1982年建造第一座水坝以来，已经实施了各种形式的鱼类救援方案。
Huang Zhenli, the deputy engineer-in-chief at the China Institute of Water Resources and Hydropower Research in Beijing, and his colleague Li Haiying developed an analytical tool that models the impact of the Yangtze River dams on its fish populations.
北京中国水利水电科学研究院副总工程师黄振利和他的同事李海英开发了一种分析工具，可以模拟长江大坝对鱼类种群的影响。
They focused on five iconic species: the Chinese sturgeon (Acipenser sinensis), the Yangtze sturgeon (Acipenser dabryanus), the Chinese paddlefish (Psephurus gladius), the Chinese sucker (Myxocyprinus asiaticus) and the largemouth bronze gudgeon (Coreius guichenoti).
他们重点关注了五个标志性物种：中华鲟鱼（Acipenser sinensis）、长江鲟鱼（Acipenser dabryanus）、中国白鲟（Psephurus gladius）、中华胭脂鱼（Myxocyprinus asiaticus）和大口铜鱼（Coreius guichenoti）。
By the time of the analysis, the paddlefish was already extinct. The Yangtze sturgeons are being kept alive only through captive-breeding programmes. The Chinese sturgeon is critically endangered. The International Union for Conservation of Nature lists the sucker as vulnerable, and the gudgeon as endangered.
到分析的时候，白鲟已经灭绝了。长江鲟鱼只能通过人工繁殖的方式存活。中华鲟是极度濒危的物种。国际自然保护联盟将其列为易受伤害的物种，并将其列为濒危物种。
The researchers’ modelling found that all five species will be entirely extinct or extinct in the wild by 2030.
研究人员的模型发现，到2030年，这五个物种将完全灭绝或在野外灭绝。
David Dudgeon, a retired freshwater ecologist at the University of Hong Kong, says that the study is helpful in identifying the effect of the dams on the five species, particularly the understudied Chinese sucker. “There is nothing much that surprises me about the conclusions of the study,” he says. “It is good to see a well-integrated investigation of these five species.”
香港大学的退休淡水生态学家大卫杜金说，这项研究有助于确定大坝对五个物种的影响，特别是研究不足的中国吸盘。他说：“这项研究的结论没有什么让我感到惊讶的。”“很高兴看到对这五个物种进行了全面的调查。”
However, not all researchers are convinced by the study. Wei Qiwei, a conservation researcher at the Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, in Wuhan, says that the authors’ work “deserves to be encouraged”, but disagrees with their conclusions.
然而，并不是所有的研究人员都相信这项研究。位于武汉的中国水产科学研究院长江水产研究所的保护研究员魏启伟表示，作者的工作“值得鼓励”，但不同意他们的结论。
Wei — who co-authored a 2020 paper2 that declared the Chinese paddlefish extinct — says the predictions that all species will be extinct or near extinct in by 2030 can’t be relied on because the parameters in the analysis are uncertain and difficult to quantify.
魏——他与人合着了2020年的论文 2 ，宣布中国白鲟灭绝——他说，到2030年所有物种都将灭绝或接近灭绝的预测是不可靠的，因为分析中的参数是不确定的，难以量化。
Xie Ping, a freshwater ecologist at the Institute of Hydrobiology (IHB) of the Chinese Academy of Sciences in Wuhan, agrees that it might be too soon to draw definitive conclusions from the models’ findings. “More needs to be done to cover more fish species in more geographic regions, so as to validate the effectiveness of the models and to optimize their parameters,” Xie says.
武汉中国科学院水生生物研究所的淡水生态学家谢平（音译）也认为，从模型的发现中得出明确的结论可能还为时过早。“需要做更多的工作来覆盖更多地理区域的更多鱼类物种，以验证模型的有效性并优化其参数，”谢说。
‘Six misjudgements’ “六个错误判断”
The authors blame the dams, and the lack of specialized passageways for migratory fish to bypass the dams — known as fish-ladders — for the five species’ collapse.
作者将这五个物种的灭绝归咎于大坝，以及缺乏专门的通道让洄游鱼类绕过大坝–被称为鱼梯。
“To prevent more migratory fishes from going extinct in China, [its] dam-related fish-rescue programmes must undergo fundamental changes,” Huang says.
“为了防止更多的洄游鱼类在中国灭绝，与大坝有关的鱼类救助计划必须进行根本性的改革，”黄说。
As fish numbers continued to decline from the 1980s onwards, China stepped up its efforts to safeguard the ecology and environment of the Yangtze.
自20世纪80年代以来，由于鱼类数量持续下降，中国加大了保护长江生态和环境的力度。
In 2021, it commenced a ten-year fishing ban and increased its restocking of the river with young, captive-bred fish.
于二零二一年，该公司开始实施为期十年的禁渔令，并增加投放人工繁殖的幼鱼。
位于长江上游金沙江上的乌东德水电站于2020年投入运营–此前中国白鲟被宣布灭绝。图片来源：CFOTO/Future Publishing via Getty
However, the authors say that it was not enough. They describe “six misjudgements” of these fish-conservation campaigns, including that overfishing is the primary cause of the population declines; and that restocking is a “viable strategy” for mitigating the effects of the dams.
然而，作者说这还不够。他们描述了这些鱼类保护运动的“六个错误判断”，包括过度捕捞是种群下降的主要原因；以及重新放养是减轻大坝影响的“可行策略”。
Wei and his team lead the scientific research behind the current conservation plan. He says that the dams’ impacts on fishes exist, but “one cannot ignore other factors”, such as overfishing.
魏和他的团队领导着目前保护计划背后的科学研究。他说，大坝对鱼类的影响是存在的，但“人们不能忽视其他因素”，如过度捕捞。
“I believe if the 10-year fishing ban had been introduced to the Yangtze River 30 years earlier, the Chinese paddlefish would not be extinct. Nor would the Chinese sturgeon, the Yangtze sturgeon and the Chinese sucker get so close to extinction,” Wei notes.
“我相信，如果早30年在长江实行10年禁渔期，中国白鲟就不会灭绝。「中华鲟、长江鲟、中华白鲟也不会濒临灭绝」，魏文哲指出。
As for restocking from captive-bred populations, he describes it as “the most important protection and restoration task” for the Chinese sturgeon and Yangtze sturgeon.
对于人工养殖种群的放流，他形容这是中华鲟和长江鲟”最重要的保护和恢复任务”。
A 2023 study led by IHB researchers3 found that a 2017 pilot fishing ban introduced to the Chishui River — an upstream tributary of the Yangtze — was “an effective measure to facilitate fish resources recovery”.
由IHB研究人员 3 领导的2023年研究发现，2017年在长江上游支流赤水河引入的试点禁渔令是“促进鱼类资源恢复的有效措施”。
Steven Cooke, a biologist specializing in fish ecology and conservation at the Carleton University in Ottawa, says that science-based restocking can work “quite well” in cases such as the white sturgeon (Acipenser transmontanus) in North America. “But if the habitat is degraded and fish can’t complete their life cycles, then stocked fish may not survive,” Cooke says.
渥太华卡尔顿大学专门研究鱼类生态和保护的生物学家史蒂文·库克说，以科学为基础的放养在北美的白色鲟鱼（Acipenser transmontanus）等情况下可以“相当好”。库克说：“但是，如果栖息地退化，鱼类无法完成它们的生命周期，那么放养的鱼类可能无法生存。”
Dudgeon, meanwhile, regards the paper’s criticism of restocking of the Yangtze as being “well-founded”.
与此同时，杜金认为该报对长江恢复放养的批评是“有根据的”。
“There is absolutely no evidence that sturgeon restocking has enhanced wild populations, despite the release of millions of cultured juveniles … [and] the fact that the practice has continued for many years,” he says.
“绝对没有证据表明鲟鱼放养增加了野生种群，尽管数百万的养殖幼鱼被释放…… [和]这种做法已经持续多年，”他说。