China is the world’s top fish consumer and is spending billions on technology designed to restock the oceans. But will this expensive experiment actually work?
A short ferry ride from the port city of Yantai on China’s northeastern coast is Genghai No. 1, a 12,000-ton oil-rig-style ring of metal rigs, advertised as a hotel and entertainment complex. Upon arrival, guests hop on the docks and on to reach an offshore facility: components of a cruise ship, components of a high-tech laboratory, all arranged on approximately 800 meters of floating gangways. Their focus – the “sparkling diamond” on Genghai No. 1, according to China’s official news firm, is a seven-story guest center, designed to resemble a cartoon starfish.
Jack Klumpp, a YouTuber from Florida, became one of the first 20,000 tourists to explore Genghai’s visitor center following its opening in May 2023. In his series I’m in China with Jack, Klumpp strolls around a water park cutely decorated in Fisher-Price yellow and turquoise, and indoors, he is excited to spot the hull of China’s deep-sea submersible Jiaolong. In reality, the sea here is only about 10 meters deep, and the submersible is only a model. Its journey into the ocean’s depths is an immersive digital experience rather than real adventure, but the floor of the sub rocks and shakes under his feet like a theme park ride.
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Looking at Klumpp at the sumptuous Genghai Marine Hotel, it’s hard to see why anyone would build this tourist charm on a seaside platform, nearly a mile away on the Bohai Strait. But the answer lies at the other end of the alley in the tourist hub of Genghai, where, on a smaller, more practical platform, he learned to cast a worm thread over the edge and catch a large sea bream.
Genghai is a rare tourist destination, where 200,000 “high-quality marine fish” breed every year, according to a recent China Daily interview with Jin Haifeng, deputy general manager of Genghai Technology Company, a subsidiary of the company. public. shipbuilder Shandong Marine Group. Only a handful of them are caught among recreational fishermen like Klumpp. The vast majority is released into the ocean through a procedure known as marine farming.
Since 2015, China has built 169 “national demonstration ranches” – adding Genghai No. 1 – and dozens of smaller-scale facilities, which together have laid 67 million cubic meters of synthetic reefs and planted seagrass beds. in a domain across Manhattan, while releasing at least 167 billion juvenile fish and shellfish into the ocean.
The Chinese government sees these pictures as pressure and a reaction to the stark reality of the collapse of fisheries in China and around the world, with catches off China’s coasts having decreased by 18% in less than a decade. In the face of this decline, marine farms may be offering a win-win solution: a way to repair wild marine ecosystems while increasing fishery catches.
Genghai, which according to “Sea Harvest,” sits atop what Jin calls an “underwater ecological oasis” built by developers. In the middle of the circular walkway, synthetic marine habitats are home to shrimp, algae, and fish, in addition to the redfish with mind-blowing eyes and a fish with a parrot-like beak, known as a spotted knife jaw.
The facility is a next-generation showcase for the country’s ambitious plans, which call for 200 pilot projects by 2025. It’s a 5G-enabled, AI-equipped “ecological” ranch that features submarine robots for underwater patrols and “intelligent breeding cages” that collect environmental data in near-real time to optimize breeding by, for example, feeding fish automatically.
In a paper published through the Chinese Academy of Sciences, China’s largest clinical institute, a no-nonsense fisheries expert outlines plans for an attractive, technology-driven long-term in which production and conservation go hand in hand. hand: eco-ranches line the coast, seagrass meadows and coral reefs grow back around them, and autonomous robots sustainably harvest mature seafood.
But now, Chinese researchers say, is the time to take stock of lessons learned from the rapid rollout of ranching to date. Before the country invests billions more dollars into similar projects in the coming years, it must show it can get the basics right.
Developing nations have historically faced a trade-off between plundering marine resources for development and protecting ecosystems for future generations, says Cao Ling, a professor at Xiamen University in eastern China. When growing countries take more than natural ecosystems can replenish, measures like seasonal fishing bans have been the traditional way to allow fisheries to recover. Marine ranching offers an alternative to restricting fishing—a way to “really synergize environmental, economic, and social development goals,” says Cao—by actively increasing the ocean’s bounty.
It’s now a “hot topic” in China, says Cao, who grew up on his family’s fish farm before studying at the University of Michigan and Stanford. In fact, “marine farming” has become such a buzzword that it can be tricky to say what it means, as it encompasses flagship services such as Genghai No. 1 (combining clinical studies with enclosures (industrial-scale aquaculture, recreational fishing services and marine energy). ) and a bewildering array of structures, including floating offshore wind farms with huge fish cages and 100,000-ton “mobile marine ranches”; In reality, there are even entire aircraft carriers for fish farms. islands, such as Wuzhizhou, in the shape of a butterfly, off the southern tropical coast of China, that have been designated as breeding areas.
To perceive what a seafaring ranch is, the easiest way is to go back to the roots of the practice. In the early 1970s, California, Oregon, Washington and Alaska passed laws allowing facilities to be built to replenish salmon populations after the rivers where they historically spawned were decimated by pollutants and hydroelectric dams. The concept was necessarily twofold: raising fish in captivity and introducing them to hatcheries in the Pacific. Since 1974, when the first marine ranches were built in the United States off the coasts of California and Oregon, ranchers have built synthetic habitats, typically concrete reef structures, that developers hoped could provide breeding spaces to house valuable reserves of publicity and threatened. marine species can simply be housed. restored.
Today, fish farming is a $200 billion industry that has had a catastrophic environmental impact, blighting coastal waters with streams of fish feces, pathogens, and parasites.
Marine ranching has rarely come close to fulfilling this potential. Eight of the 11 ranches that opened in the US in the 1970s were reportedly shuttered by 1990, their private investors having struggled to turn a profit. Meanwhile, European nations like Norway spent big on attempts to restock commercially valuable species like cod before abandoning the efforts because so few introduced fish survived in the wild. Japan, which has more ranches than any other country, made big profits with scallop ranching. But a long-term analysis of Japan’s policies estimated that all other schemes involving restocking the ocean were unprofitable. Worse, it found, releasing docile, lab-bred fish into the wild could introduce genetically damaging traits into the original population.
Today, marine fish farming is considered a strange branch of traditional fish farming, in which fish of a single species are intensively fed in small, closed enclosures. This type of feedlot-style aquaculture has grown enormously over the last half century. Today, it is a $200 billion industry that has had a catastrophic environmental impact, devastating coastal waters with floods of fish feces, pathogens and parasites.
However, coastal countries have not been discouraged by the poor effects of marine agriculture. Many governments, especially in East Asia, see the release of millions of young fish as a cheap way to show off to hard-hit fishing communities, whose livelihoods are disappearing as fisheries near collapse. At least 20 countries continue to experiment with various combinations of repopulation and habitat improvement, joining efforts to transplant corals, reforest mangroves and plant seagrass beds.
Every year, at least 26 billion juvenile fish and shellfish, from 180 species, are intentionally released into the world’s oceans, or 3 for every user on the planet. Taken together, those efforts constitute a vast, little-noticed, ongoing experiment in the wild marine biome.
China, with a population of 1.4 billion people, is the world’s undisputed fish superpower, home to the largest fishing fleet and more than half the planet’s fish farms. The country also overwhelms all others in fish consumption, using as much as the four next-largest consumers—the US, the European Union, Japan, and India—combined and then doubled. But decades of overfishing, compounded by runaway pollution from industry and marine aquaculture, have left its coastal fisheries depleted.
Around many Chinese coastal cities like Yantai, there is a feeling that things “could not be worse,” says Yong Chen, a professor at Stony Brook University in New York. In the temperate northern fishing grounds of the Bohai and Yellow Seas, stocks of wild fish such as the large yellow croaker—a species that’s critically endangered—have collapsed since the 1980s. By the turn of the millennium, the Bohai, a densely inhabited gulf 100 miles east of Beijing, had lost most of its large sea bass and croaker, leaving fishing communities to “fish down” the food chain. Fishing nets came up 91% lighter than they did in the 1950s, in no small part because heavy industry and this region’s petrochemical plants had left the waters too dirty to support healthy fish populations.
As a result, over the past three decades China has instituted some of the world’s strictest seasonal fishing bans; recently it has even encouraged fishermen to find other jobs. But fish populations continue to decline, and fishing communities worry for their future.
Marine agriculture has gained a great boost thanks to the levels of government; it is considered an ideal test case for President Xi Jinping’s “ecological civilization” agenda, a long-term environmentally sustainable expansion strategy. Since 2015, livestock farming has been included in successive five-year plans, in the country’s high-level plan documents, and the farm structure has been supported by an initial investment of 11. 9 billion yen ($1. 8 billion). China is now on track to release 30 billion juvenile fish and shellfish by 2025.
The country has indicated that it is in a position to retaliate even harsher, in a way that may just inflict serious economic hardship on its biggest economic rival.
So far, this practice has led to an unlikely model: the sea cucumber. It is a spiny animal that lives on the seabed and, like Japanese scallops, does not stray far from release sites and requires little effort to be captured by herders. In northern China, sea cucumbers are incredibly valuable. They are one of the most beloved dishes on Yantai menus, where they are served chopped and stewed with green onions.
Some ranches have experimented with raising multiple species, including profitable fish like sea bass and shellfish like shrimp and scallops, alongside the cucumber, which thrives in the waste that other species produce. In the northern areas of China, such as the Bohai, where the top priority is helping fishing communities recover, “a very popular [mix] is sea cucumbers, abalone, and sea urchin,” says Tian Tao, chief scientific research officer of the Liaoning Center for Marine Ranching Engineering and Science Research at Dalian Ocean University.
Today, most ranches are geared toward enhancing fishing catches and have done little to deliver on ecological promises. According to Yang Hongsheng, a leading marine scientist at the Chinese Academy of Sciences, the mix of species that has so far been introduced has been “too simple” to produce a stable ecosystem, and ranch builders have paid “inadequate attention” to that goal.
The construction of sea ranches is funded by grants of around 20 million yen ($2. 8 million) from the Chinese government, but the ranches are operated through personal corporations. These corporations make their income by generating seafood, but increasingly grow other revenue streams, such as tourism and recreational fishing, which have seen a boom in recent years. So far, this owner-operator style has provided little incentive to look beyond tried-and-true strategies that closely resemble aquaculture (such as Genghai No. 1’s closed offshore fishing cages) and has done little to inspire contributions to the oceans. fitness beyond the ranch footprint. “Many corporations just need to get cash from the government,” says Zhongxin Wu, an associate professor at Dalian Ocean University who works with Tian Tao.
Making ranches more sustainable and environmentally friendly will require an immediate expansion of the knowledge base on understudied marine species, says Stony Brook’s Yong Chen. “For a sea cucumber, the first thing you want to know is its life cycle, right? How they reproduce, how they live, how they die,” he says. “For many key marine species, we have little idea of the temperature or the situations in which they prefer to reproduce and grow. ”
Chinese universities are world leaders in applied sciences, from agricultural research to materials science. But fundamental questions aren’t always easy to answer in China’s “quite unique” research and development environment, says Neil Loneragan, president of the Malaysia-based Asian Fisheries Society and a professor emeritus of marine science at Murdoch University in Australia.
According to Loneragan, the central government’s dominant influence over livestock progress means that researchers have to walk a tightrope between their two bosses: the university principal and the party leader. Marine biologists need to understand the basics, “but researchers would need to do so in a future way that demonstrates the economic benefits to the industry and therefore the benefits of the investment to the government,” he says.
Many efforts aim to address known problems in the life cycles of captive-bred fish, such as inadequate breeding rates or the tough survival odds for young fish when they reach the ocean. Studies have shown that fish in these early life stages are particularly vulnerable to environmental fluctuations like storms and recent ocean heat waves.
One of the most radical solutions, tested by Zhongxin Wu, would be their physical condition before being released from hatcheries into the wild. Currently, Wu says, fish are simply collected in oxygenated plastic bags and released into ocean nurseries, but it is clear that many of them are weak or lack survival skills. In response, his team is coming up with a “wild training” toolkit. “The main focus is swim training,” he says. In fact, the juveniles are forced to swim against the current, in a kind of aquatic ribbon, to help them acclimatize to the demands of nature. Another strategy, he says, is to increase water temperatures and introduce other species to prepare them for the seagrasses and kelp forests they may encounter in the outside world.
Wu says that greater habitat improvement strategies have greater potential to increase the potency of marine agriculture. Today, most ranches create underwater environments by employing prefabricated concrete structures installed under 20 meters of water, with a rough surface to stimulate coral or algae growth. The typical Chinese ranch aspires to 30,000 cubic meters of synthetic reefs; In the conservation-oriented breeding area around Wuzhizhou Island, for example, 1,000 cast concrete reef structures were placed around the tropical island’s shores. Fish stocks have increased tenfold in the last decade.
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This is by far the most expensive part of China’s ranching program. According to a national evaluation coauthored by Cao Ling, 87% of China’s first $1 billion investment has gone to construct artificial reefs, with a further 5% spent on seagrass and seaweed restoration. These costs have brought both questions about the effectiveness of the efforts and a drive for innovation. Across China, some initial signs suggest that the enhancements are making a difference: Sites with artificial reefs were found to have a richer mix of commercially important species and higher biomass than adjacent sites. But Tian and Wu are investigating new approaches, including custom 3D-printed structures for endangered fish. On trial are bungalow-size steel ziggurats with wide openings for yellowtail kingfish—a large, predatory fish that’s prized for sashimi—and arcs of barrel-vaulted concrete, about waist height, for sea cucumbers. In recent years, structures have been specifically designed in the shape of pyramids, to divert ocean currents into oceanic “upwellings.” Nutrients that typically settle on the seafloor are instead ejected back up toward the surface. “That attracts prey for high-level predators,” says Loneragan, including giant tuna-like species that fetch high prices at restaurants.
So will China soon rely on marine farms to fill the seas? We don’t have enough knowledge yet to say that. The Qingdao Marine Conservation Society, an environmental NGO, is one of the few independent organizations that systematically evaluates farm backgrounds and, according to founder Songlin Wang, “has failed to locate enough independent and data-based survey locations. ” science that can measurably determine maximum marine ranges.
One answer to the lack of knowledge may simply be the kind of new generation on display at Genghai No. 1, where robotic patrols and underwater sensors promptly feed a huge dashboard that measures water quality, changes in the ocean environment and the behavior of fish. After decades of being a relatively low-tech business, livestock farming in China has embraced those new technologies since the start of the latest five-year plan in 2021. The inventions promise efficiency, reducing costs and making ranches more resistant to the elements. time. herbal fluctuations and disasters, according to the Chinese Academy of Sciences.
But Yong Chen, whose lab at Stony Brook is partnered with Chinese researchers, is skeptical that the researchers are collecting and sharing the right data. “The challenge is that yes, there is this visualization. So what? ” said. “[Marine farming companies] are willing to invest cash in this type of infrastructure, create this type of big display, and other people will walk in and say ‘Wow, look at that!’ »”, he adds. “Yes, it is beautiful. In fact, this will impress leaders. Significant others will give you cash for this. But as a scientist, my question is: How can this influence decision-making next year? »
Will China soon be relying on marine ranches to restock the seas? We still don’t have anywhere near enough data to say.
“Sharing data is complicated in China,” Cao explains Ling. La most of the knowledge produced through personal corporations remains on its servers. But Cao and Chen say that governments — local or central — could simply facilitate a more open exchange of knowledge in order to guide ranch design and policy.
But the Chinese central government is convinced by what it has observed and plans to increase its investments. Tian, who heads the government committee on marine agriculture, says he recently learned that the next 10-year plan will aim to increase the number of pilot farms from two hundred to 350 by 2035. Each of them is expected to receive support. through two hundred million yen. ($28 million): 10 times the typical existing investment. Specific policies will be announced next year, but he hopes the ranches will no longer be funded as stand-alone facilities. Instead, subsidies will most likely be given to cities like Dalian and Yantai, which can plan on land and sea and find tactics to link advertising fishing with power generation and tourism, while reducing advertising pollutants. .
Tian has an illustration that aims to visualize the coming tech-driven ecological ranching system, a sort of “marine ranching 3.0”: a sea cove monitored by satellites and restored to such good health that orcas have returned to its fish-filled waters. It’s a near-utopian image seemingly ripped from a 1960s issue of Popular Science. There’s even stranger research that aims to see if red sea bream like the one Jack Klumpp caught can be conditioned like Pavlov’s dogs—in this case to flock to the sound of a horn, so the ocean’s harvest would literally swim into nets at the press of a button.
So far, China’s marine farming program falls far short of those goals, despite some remote signs of success. But in the end the most important thing is to find a “balance point” between industry and sustainability, Cao believes. Take Genghai No. 1 as an example: “It’s very beautiful!” » he said laughing. “And it’s expensive for the initial investment. ” If such ranches want to contribute to China’s “ecological civilization” in the long term, they will want to demonstrate that they are generating genuine profits and not simply gobbling up more resources in a disappearing ocean.
Matthew Ponsford is a freelance journalist in London.
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