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For years, reports of illegal fishing activities have dogged China’s distant-water fishing fleet. Now, China is significantly tightening regulations governing these fishing vessels for the first time in 17 years, with a slew of new rules taking effect throughout 2020, including harsher penalties for captains and companies found to have broken the law.

Estimated at a minimum of 2,900 vessels, the country’s distant-water fleet, active outside its maritime borders, dwarfs that of other nations. Since 2003 it has grown by at least 1,000 boats and doubled its reported annual catch.

The rule changes from China include revisions to the Distant-Water Fishing Management Regulations, new Management Measures for High Seas Squid Fishery and a new Rule for High Seas Transshipment released earlier this year; as well as a revision to the Administrative Measures of the Vessel Monitoring System released in 2019. They all take effect between January 2020 and January 2021. Leaving less space for illegal activities, the changes are geared toward increasing transparency and promoting more sustainable practices.

“China is the country that will shape what the future of ocean health becomes,” said Douglas McCauley, professor of marine biology at the University of California, Santa Barbara. “No other nation has more say as to what will become of the future of our ocean.”

The country hauls in around 15% of the world’s reported wild fish catch, according to a 2020 U.N. Food and Agriculture Organization (FAO) report. Discrepancies in reported fish catches and lack of transparency over fleet sizes globally mean no one really knows how much seafood humans remove from the ocean. But studies indicate an alarming drop in marine fish and invertebrate populations over the past 50 years.

More than a third of the planet’s fish stocks are overfished to biologically unsustainable levels, the FAO report said, with a further 60% of stocks fished to the sustainable maximum. Those numbers have far-reaching implications not only for marine ecosystems but for humans: fisheries provide direct employment for almost 60 million people globally and around 20% of essential protein intake for more than 3 billion people, according to the report.

China has previously signalled its intent to promote sustainable fishing practices. In 2017, the country pledged to cap its distant-water fleet at 3,000 vessels by 2020 and outlined comprehensive intentions in its 13th Five-Year Plan for the Development of Distant-Water Fishery. However, it has taken little concrete action until now.

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china fishing regulations
Chinese and Guinean crewmembers sort fish on the Fu Yuang Yu 380, a Chinese fishing boat operating in Guinean waters in 2017. Image © Pierre Gleizes / Greenpeace.

The New Rules

Changes to the Distant-Water Fishing Management Regulations, which took effect April 1, include harsher punishment for those caught breaking the rules, a clamp-down on vessel monitoring, new port management procedures, stricter certification requirements, and clarification of penalties, responsibilities and enforcement measures, industry experts said. The country’s Wildlife Protection Law joined the list of acts that transgressions at sea are punishable under.

The revised regulation shifts the focus from “rational” to “sustainable” use of marine resources from the first paragraph. Prohibitions on illegal, unreported and unregulated (IUU) fishing activity, a term not mentioned in the previous version, are now prominent in four separate clauses, and references to protection and sustainability have doubled in frequency, according to a comparative translation provided by Tabitha Mallory, founder of the Seattle-based consulting firm China Ocean Institute.

The Port State Measures Agreement (PSMA) of 2016 is the first internationally binding agreement aimed at combatting IUU fishing. The idea is to prevent vessels engaging in IUU activity from landing catches by denying them entry to ports globally. While China committed to joining the PSMA in 2017, it has yet to follow through. However, the updated distant-water fishing regulations seem to pave the way for China to do so. Newly added Article 38 explicitly prohibits ships on IUU lists held by international fishery organizations from entering Chinese ports except in special circumstances. The new rules place responsibility for investigating and handling ships entering illegally or under special circumstances with Chinese authorities, in line with both Chinese law and international treaties agreed to by China.

Previously, punishment meted out to companies blacklisted for IUU fishing transgressions was limited, according to Pan Wenjing, a Beijing-based forest and ocean project manager with Greenpeace East Asia. “The company only needed to pay the fine then could head back to sea fishing again,” she said. Now, ship captains will lose their captain’s licence for five years and company managers will be stripped of their managerial role for three years.

Insurance companies, creditors and other fishing industry support businesses will likely be less willing to work with high-risk businesses such as those on China’s blacklist, said Philip Chou, an expert on distant-water fishing with international conservation group Oceana. That highlights how the country’s new rules have the potential to bring about real change at all levels of the industry, he said.

The new rules address the issue of ships committing transgressions while “going dark” by switching off their transponders so their locations can’t be identified. Hourly transponder reporting is now a legal requirement, up from every four hours before Jan. 1, 2020. Chou said this increases the potential to investigate suspicious activity, such as ships meeting up at sea or approaching marine protected areas, and provides clearer measures for frequent violators.

China hasn’t previously monitored high-seas transshipment — the practice of transferring cargo from one ship to another at sea, which fishers can use to hide the true origin or volume of their catch — at all. The new Rule for High Seas Transshipment introduces reporting and onboard independent observers for such transfers, and bans pollution during operations, Pan said.

The other first for China is seasonal closures of squid fishing. The new Management Measures for High Seas Squid Fishery bans Chinese vessels from fishing squid in the southwest Atlantic from July to September and in the eastern Pacific from September to November, in an effort to protect overfished stocks.

“These strong measures make the regulation a tiger with sharp teeth,” Pan said of the update to the distant water fishing management regulations from China. “But it still depends on whether it can be effectively enforced.”

China’s Ministry of Agriculture and Rural Affairs, which oversees the country’s fisheries, did not respond to Mongabay’s requests for comment.

Dodgy Fishing Practices

IUU fishing is so pervasive that one in five wild-caught fish is estimated to have been caught illegally, with a total annual value of up to $23.5 billion, according to a 2018 Pew Trust report. China’s distant-water fleet has been widely implicated in illegal practices, ranking worst out of 152 coastal states on a global IUU fishing index developed by U.K.-based Poseidon Aquatic Resource Management and the Geneva-based non-profit Global Initiative Against Transnational Organized Crime.

February 2019 saw 294 fishing boats making the most of peak squid season in the southwest Atlantic Ocean, just outside Argentina’s exclusive economic zone (EEZ). Of them, 256 turned off their vessel monitoring system, and 87% of the vessels that did so were flagged to China, according to a 2019 report by Washington, D.C.- based security analyst C4ADS. Dark fleets of Chinese squid boats have also been implicated in $440 million worth of flying squid (Todarodes pacificus) illegally taken from North Korean waters in 2017 and 2018, according to a recent study in the journal Science Advances.

While not always illegal, going dark is useful cover for fishing illegally inside protected areas or during seasonal closures, or simply for nipping into the EEZ of a country whose waters you have no permit to fish. China’s revised regulation prohibits this kind of intentional interference with vessel monitoring systems.

The Indonesian crew of a fleet of Chinese tuna longliners fishing the Western Pacific recently reported they had been illegally shark finning. Pictures they provided indicate they were targeting endangered species, such as oceanic whitetips (Carcharhinus longimanus) and hammerheads (Sphyrna spp.).

Four crew of one boat, the Long Xing 629, died of an unidentified illness while in service between December 2019 and April 2020. Three of their bodies were dumped at sea. Crewmates reported human rights abuses including forced labor.

“This incident clearly shows the need for policy change related to workers’ rights on board fishing vessels and for better monitoring, control, and surveillance measures,” Chou said. Regulations that took effect in April mean that going forward companies like the one that owns the Long Xing 629 and its sister ships, Dalian Ocean Fishing Co Ltd., should be publicly blacklisted. The company did not respond to Mongabay’s request for comment.

Another common practice among fleets of many nations is to hide the true owner of a fishing boat or fleet with a front, or shell company, a practice that causes huge transparency issues. For instance, Ghanaian law bans international companies from its commercial fishing sector and prohibits joint ownership of enterprises between Ghanaians and foreigners. Yet an estimated 90% of industrial trawl vessels plying Ghana’s waters have links to Chinese ownership, according to a 2018 report from the U.K.-based NGO Environmental Justice Foundation.

Public data from the Chinese Ministry of Agriculture and Rural Affairs confirms that several ships with previous sanctions and fines for IUU offenses that are registered to Ghanaian companies are in fact owned by a Chinese company, according to a 2019 investigation by China Dialogue Ocean.

China’s 13th Five-Year Plan for the Development of Distant Water Fishery included the intent to abide by regulations of countries where China ’s fleet operates, and the revised distant-water fishing regulations include measures to make the flagging of distant water vessels more transparent. Together these suggest that, as of April 1, China should be cooperating with countries like Ghana to police illegal shell companies.

Is it Enough?

“The current revisions are a commendable step to make China’s DWF management regime more in line with international norms and practices,” Chou said. He pointed out that resolving systemic issues of IUU fishing and sustainability globally would require international improvements to implementation of existing policy and further reform, and that China’s revisions are not a standalone panacea.

Even so, the increasing willingness of China to better manage its distant-water fishing, plus the new regulations, could substantially improve fishing and supply chain management globally because of the country’s position as the largest distant-water fishing power on the planet, Pan said. But that can happen only if China enforces its new rules.

If it does, and the country ranked worst in the world for IUU fishing can change course, the implications for the sustainability of global fisheries are huge, experts consulted for this story agreed.

“A solution waiting to happen,” is how McCauley referred to China’s potential to lead fishing reform. “If China elects to govern its fisheries more sustainably, not only does China benefit, the world benefits. China can act fast — when it wishes to do so.”

This article was originally published on Mongabay, written by Elizabeth Fitt, and is republished here as part of an editorial partnership with Earth.Org.


Wild caught bluefin tuna is one of the most unsustainable seafood dishes in Hong Kong, with the Pacific bluefin tuna listed as vulnerable, Atlantic bluefin tuna listed as endangered and the southern bluefin tuna listed as critically endangered on the IUCN Red List. So what about farmed bluefin tuna? Is this a more sustainable option? While bluefin tuna farms, mainly located in Australia, the Mediterranean and Japan, might at first glance seem to be an acceptable replacement to the wild-caught alternative, closer examination shows otherwise.

Bluefin tuna is a carnivorous species that sits at the top of the food chain. In aquaculture, it has a high Fish In Fish Out ratio (FIFO). FIFO is an environmental performance benchmark used to measure the efficiency at which the aquaculture converts a weight-equivalent unit of wild fish into a unit of cultured fish. Bluefin tuna has an average FIFO ratio of 15:1. In other words, for every tonne of farmed bluefin tuna, a total of 15 tons of feed is required. By comparison, farmed salmon and trout have a FIFO ratio of 0.82:1, while species in the Cyprinidae family such as grass carp only has a FIFO rate of 0.02:1. In 2015, the average aquaculture FIFO ratio was 0.22:1.

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Bluefin tuna commands one of the most expensive per pound prices on the global seafood market, so it is in the interest of farmers to increase their size. By feeding bluefin tuna a mixture of sardine, sand eel, saury, chub mackerel, Japanese horse mackerel, and cuttlefish, aquaculture farmers can increase the weight of a single fish by 10-20kg. This makes farmed bluefin tuna environmentally inefficient and unsustainable.

In the WWF Seafood Guide, which covers over 70 of the most familiar seafood items in the city, both farmed and wild-caught bluefin tuna fall into the “avoid” category. The guide has three categories: green – recommended; yellow – think twice; red – avoid. The green category indicates well-managed fisheries where seafood is caught or farmed in an ecologically-friendly manner. The yellow category indicated fisheries that are at risk of becoming unsustainable. The red category indicates fisheries that are over-exploited, or seafood that is caught or farmed in an ecologically-unfriendly manner.

Sustainable replacements to bluefin tuna include yellowfin tuna caught with handlines in Indonesia and the Philippines. Handline fishing is highly selective and therefore has a low bycatch rate. Additionally, these yellowfin fisheries have a more solid management framework that prevents fishing during certain seasons, giving fish stocks a chance to recover.

Featured image by: Wikimedia Commons

This article was originally published on WWF-Hong Kong, and is republished here as part of an editorial partnership with Earth.Org.

Shark fin soup is said to be the food of emperors, but a new study finds this “luxury” dish may not be so favorable to the person who eats it. A team of international researchers discovered that shark fin soup contains high levels of mercury and other heavy metals- in most cases, much higher than what’s legally considered safe for human consumption.

Shark fin soup has a long history in Chinese culture. Emperor Taizu of the Northern Song, who ruled China between 960 and 976, apparently ate shark fin soup to display his power and wealth. From that point on, the dish became a status symbol and much-sought-after food item in China, served throughout the Song dynasty (960-1279), the Ming Dynasty (1368-1644), and the Qing Dynasty (1644-1912). While it briefly disappeared from the menu when the Chinese Communist Party assumed power in 1949, it reemerged in the 1980s as a dish to signify prosperity and good fortune.

Even today, shark fin soup continues to be a popular food choice in China and Hong Kong, and there’s even a growing demand in other Asian countries like Thailand, Vietnam and Indonesia. In Hong Kong, it’s frequently served as a delicacy at weddings and New Year’s banquets, but you can also find “everyday” versions of the soup at most restaurants.

To feed the insatiable demand for shark fin soup, about 100 million sharks are killed every year, according to one study. While it’s legal to trade the fins of many shark species, other sharks are protected under CITES Appendix II, which only allows trade when special permits have been granted. But CITES regulations have not managed to stop the many illegal parts of the global shark fin trade.

While previous studies have investigated mercury levels in the fins of wild sharks, this study looked at mercury levels in shark fins that have been processed and prepared for sale in China and Hong Kong.

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shark fin soup metals
Shark fin soup. A new study shows that shark fin soup contains levels of mercury not safe for human consumption (Source: Mongabay via Wikipedia Commons).

“The processing sharks fins undergo to be ready to be used in shark fin soup is very secretive and involves different chemicals that might affect mercury concentrations,” Laura García Barcia, a doctoral candidate at Florida International University and the study’s lead author, told Mongabay. “We wanted to assess the mercury present in the final product that goes straight to the consumer. Only one study before us had looked at mercury in processed shark fins but unfortunately, they did not have the resources to analyze the fins at the species level. Ours is the first study on processed shark fins that gives information on mercury levels by species.”

The team took 267 samples of shark fin trimmings — pieces of cartilage, muscle and skin cut off from the main part of a shark’s fin — from nine of the most common shark species that end up in soup bowls, which they distinguished through DNA testing. These included blue sharks (Prionace glauca), silky sharks (Carcharhinus falciformis), scalloped hammerheads (Sphyrna lewini), smooth hammerheads (Sphyrna zygaena), bull sharks (Carcharhinus leucas), shortfin mako sharks (Isurus oxyrinchus), great hammerheads (Sphyrna mokarran), oceanic whitetips (Carcharhinus longimanus), and several species of blacktip sharks, which they grouped together in what they called the “blacktip complex.” Using nitric acid and a spectrometer, they tested the fin trimmings for mercury and methyl-mercury, an organic, highly toxic form of mercury.

Most shark fins turned out to have five to 10 times more mercury the legal maximum amount of 0.5 parts per million, as indicated by the Hong Kong government’s Centre for Food Safety (CFS), which is similar to the Food and Drug Administration (FDA) in the United States. The highest amount was found in great hammerheads, which had mercury levels of 55.52 parts per million.

“Hammerheads are very large sharks and they are also at the top of the trophic chain,” García Barcia said. “They are sharks that can eat very large prey, and the larger prey you eat, the higher the mercury is. If we had actually looked at great white shark fins, you would have probably seen very high mercury levels also, but for us, the highest predator in our study was the great hammerhead.”

In Hong Kong, great hammerhead fins are considered to be premium products, and sold at prices equivalent to $500 to $1,000 per kilo, according to Demian Chapman, a shark researcher and one of the study’s authors.

Hammerheads “represent the most expensive and most sought after fins in the trade,” Chapman told Mongabay. “Therefore, the most expensive fins on the market also carry the highest risk of mercury toxicity. Banquet hosts often purchase these premium fins or order to honor their guests, which is ironic in light of their particular toxicity.”

Mercury enters the ocean, and into sharks’ bodies, in a variety of ways. It can come from natural sources like volcanoes, and from human activities such as gold mining, inadequate waste management, and the burning of coal, wood and oil, García Barcia said.

“Mercury in surface ocean waters has roughly tripled in the last century,” García Barcia said in an email. “Methyl-mercury biomagnifies through the food web, resulting in top predators accumulating high concentrations of this pollutant.”

“The species in our study are all large-bodied, top predators so we expected to find high amounts of mercury in the tissue samples,” she added. “Mercury concentrations depend on a long list of factors including the diet of the shark, its region of origin and the size at which it was caught.”

Right now, little is known about what mercury levels do to sharks themselves, but some studies show negative impacts of mercury on certain fish species.

“Fish can have problems with swimming performance, it affects their reproduction, the survival of the offspring is greatly reduced,” García Barcia told Mongabay. “But for now, we actually don’t know what the effects are in sharks. We think they are very similar [to other fish species], but sharks have been around for 400 million years, so maybe they just have a way to excrete it.”

While a single bowl of shark fin soup probably wouldn’t seriously affect your health, García Barcia said that prolonged consumption of shark fin soup, and other mercury-rich foods like tuna and swordfish, could lead to brain damage and changes in the central nervous system. If pregnant women consume too much mercury, their babies are more at risk of neurocognitive deficits and neuromotor disabilities.

The Hong Kong CFS website carries information about mercury in shark products, but it’s limited. For instance, there’s a warning that a shark’s tail skin contains mercury levels of 4.16 parts per million, but another page says that “mercury levels in all shark fin samples tested by the Centre for Food Safety were satisfactory” and not above the legal levels.

Gary Stokes, director of operations at Oceans Asia, a Hong Kong-based NGO, has been investigating the shark trade for 20 years, and he said that most consumers don’t realize the health risks attached to shark fins.

“The average person has no idea of the high mercury levels in shark fins,” Stokes told Mongabay. “In fact, very few have any idea of where the dish in front of them came from at all. The barbaric slaughter, the illegal vessel it was likely caught by, most crewed by slaves. Many don’t even connect that it came from an actual shark.”

Besides being high in heavy metals, shark fins tend to be processed with peroxide or bleach, Stokes said. Then they’re laid out to dry on dirty streets, sidewalks, back alleys and rooftops.

“Shark fin traders are laughing and making fools of those who dine on this ‘luxury dish,’” Stokes said. “They know the filthy path these fins have taken to the final ‘fancy bowl of soup.’ In a germaphobic Hong Kong, it baffles me how clueless some people can be. They walk past these fins in the gutter, covered in flies and bacteria, then enter a restaurant and pay US$100 a bowl because they saw a beautiful picture of a golden bowl of shark fin soup.”

Chapman says he believes that once consumers have accurate information about mercury levels in shark fins, demand for the product may go down. “Not everybody’s worried about threatened species, but everybody’s worried about their health,” he said.

The team recently sent the results from the study to Hong Kong’s CFS, although they’re still waiting on a response.

“My expectation is that the government will ramp up its own testing for things that they see in the market right now,” Chapman said. “I believe that they would find the same results that we found in our study, and my expectation is that they will start issuing advisories against eating shark fin soup.”

García Barcia also said the team is working with NGOs in Hong Kong to help spread the word about mercury levels in shark fins.

“Previous campaigns … have focused on the importance of sharks in the ecosystems or how shark populations are declining worldwide,” García Barcia said. “That’s a message that has resonated within younger audiences in Hong Kong, but not necessarily with older people that actually have the purchasing power to drive the demand for shark fin soup. So we think that a health-based approach could actually help resonate with people that … care about their own personal health, and we hope that helps further reduce the demand.”

Featured image by: Nicholas Wang

This article was originally published on Mongabay, written by Elizabeth Claire Alberts , and is republished here as part of an editorial partnership with Earth.Org. 

Ecuador has sounded the alarm after its navy discovered around 260 mostly Chinese-flagged fishing vessels in the ocean surrounding the Galápagos islands. The fleet, found just outside a protected zone, raises the prospect of damage to the protected region’s diverse ecosystem and marine life.

Chinese Fishing Fleets in the Galápagos

The fleet was spotted with satellite imaging on the borders of the Galápagos Protection Zone. The fleet was found between the boundaries of the zone and Ecuador’s territorial waters, an area that serves as a major migration route for sea creatures, including many endangered species.

Former environment minister Yolanda Kakabadse says, “This fleets’s size and aggressiveness against marine species is a big threat to the balance of species in the Galápagos.” Kakabadse and Roque Sevilla, ex-mayor of Quito, have been put in charge of designing a ‘protection strategy’ for the islands. Sevilla says that diplomatic requests would be made to request the fleet’s withdrawal. “Unchecked Chinese fishing just on the edge of the protected zone is ruining Ecuador’s efforts to protect marine life in the Galápagos,” he says. He added that the team would also seek to enforce international agreements that protect migratory species. 

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chinese vessels Galápagos
A Marine Traffic image showing the fishing fleets, represented by the orange arrows at the bottom left, as of July 27 2020 (Source: Hong Kong Free Press).

Chinese fishing vessels come every year to the seas surrounding the Galápagos islands, a UNESCO Heritage Site, but this year’s fleet is one of the largest seen in recent years. The Galápagos Marine Reserve has one of the world’s largest concentrations of shark species, including the endangered whale and hammerhead sharks. UNESCO describes the islands as a ‘living museum and a showcase for evolution’. 

Ecuador is trying to establish a corridor of marine reserves between Costa Rica, Panama and Colombia to seal off important areas of marine diversity. Kakabadse says that efforts will also be made to extend the exclusive economic zone to a 560km circumference around the islands. 

The Ecuadorean navy has been monitoring the fleet since it was first spotted in the week of July 20. The country’s defence minister Oswaldo Jarrín says, “We are on alert, conducting surveillance, patrolling to avoid an incident such as what happened in 2017.”

The incident in question refers to the capture by the navy within the Marine Reserve of a Chinese vessel, which was found to be carrying 300 tons of marine wildlife, mostly sharks. 

UPDATE AUGUST 11: Ecuador’s navy is conducting surveillance of the Chinese fishing fleet, which has grown to 340 vessels. China has promised a “zero tolerance” approach to illegal fishing and has proposed a moratorium on fishing in the area between September and November. The fishing fleets usually leave the area before that period.’

UPDATE SEPTEMBER 18: According to environmental protection NGO Oceana, the fleet are mainly fishing for squid, a vital part of the diet of endemic creatures including hammerhead sharks, as well as tuna. It has also been determined that the vessels disabled their public tracking devices, typically done to hide illegal activities.

This is a developing story. Follow Earth.Org for more updates. 

According to a study published in the journal Science, approximately 60% of fish species will struggle to reproduce in their current habitats by 2100 under the escalating pressures of the climate crisis. The study highlights how previous investigations, analysing the reproductive nature of adult fish, have underestimated the effects of the climate crisis on economically and ecologically important species. How will this impact global fish stocks, and what role does overfishing play in accelerating the reduction of fish populations? 


The study found that the rise in the Earth’s core temperature will have a significant impact on fish stocks worldwide. The researchers investigated whether saltwater or freshwater fish are more sensitive to heat across all climate zones. They examined 694 fish species’ tolerance to various temperatures, followed by an analysis on which of the species in particular are more resilient to temperature fluctuations. 

It was noted that the temperature of the water largely determines the success of reproduction, demonstrating that fish species are particularly attuned to changes in their environment- be it oceans, lakes, ponds or rivers. The researchers attributed this finding to the oxygen-limitation hypothesis, which postulates a mechanistic link between the physical development of an organism in aerobic capacity and tolerance to temperature extremes. Oxygen is a huge factor to consider when discussing energy expenditure as the warmer the climate, the more oxygen is required to function. If failure to adapt to this rise in temperature occurs, fish species are at risk of experiencing adverse health effects, such as cardiovascular collapse. 

“Our findings show that, both as embryos in eggs and as adults ready to mate, fish are far more sensitive to heat than in their larval stage or sexually mature adults outside the mating season,” explains Flemming Dahlke, a marine biologist at the Alfred Wegener Institute and lead contributor of the study. The explanation behind such variability lies in the anatomy of the fish during different respective life stages: fish embryos do not have the facilities, such as gills, to allow for greater oxygen intake, and are therefore put at a significant disadvantage when it comes to survival; mating fish require more oxygen to accommodate for the increase in body mass and energy required to successfully reproduce. The strain such requirements have on the fish pose significant health risks that their bodies are essentially unable to manage. 

Furthermore, the researchers explained that if the rise in temperatures is limited to 1.5 degrees Celsius by 2100, 10% of fish species would struggle with reproduction, or would be forced to migrate to cooler climates. However, if the Earth’s core temperature increases by 5 degrees or more, up to 60% of fish species would be affected. The current projection is a global rise in 3 degrees by the end of the century.

Although some fish species may be able to adapt, the majority would not be as fortunate- particularly where size or geographical location might inhibit locomotion or spawning abilities. 

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The Effects of Overfishing on Marine Ecosystems 

According to the Food and Agriculture Organisation of the United Nations (FAO), 33% of fisheries are overfished, and, collectively, 90% of the world’s fisheries are either overfished or fully exploited. This poses a significant threat to the infrastructure and efficiency of marine ecosystems. 

A decrease in fish diversity as a result of overfishing alters nutrient recycling in marine ecosystems, ultimately having a cascading effect on species situated lower in the food chain. Fish species contribute to this process in varying degrees depending on the rates at which they excrete essential nutrients, such as nitrogen and phosphorus, which affects other marine organisms. Once excreted, these nutrients are readily available to primary producers, such as plankton and algae, who depend on nitrogen and phosphorus to grow. Disturbances to the process of nutrient cycling affects the growth of primary producers and of other organisms who depend on these producers for food and therefore survival. This vicious cycle, starting from the top-down, further emphasises the importance of fish species and their need to reproduce. 

Illegal Fishing 

According to a study published in the journal PLoS One, illegal fishing accounts for up to US$23.5 billion worth of seafood every year. The PEW Charitable Trusts notes that, ‘by volume, illegal and unreported fishing accounts for 11 to 26 million tons of fish every year; that means up to 1 800 pounds of seafood are stolen from the seas every second’.   

Another study found that ‘Illegal and unreported catches represented 20–32% by weight of wild-caught seafood imported to the USA in 2011’. Illegal, unreported and unregulated (IUU) fishing pillages the ocean, depletes fish stocks and negatively impacts conservation efforts. In addition to affecting fish species worldwide, IUU fishing also represents a major loss of revenue, particularly to some of the poorest countries in the world where dependency on fisheries for food, livelihoods and revenues is high. 

Future Investigations 

The above data demonstrates the many downfalls overfishing and IUU fishing has on the environment, economy, and ecosystems across the world. The investigation demonstrates a deeper understanding on how fish species are being affected by the pressures of the climate crisis and the extent to which habitat loss is determined by climate-induced changes of ecosystems. The analysis will assist in improving projections on the future of worldwide fish stocks- painting a clearer picture for reports like the Special Report on the Ocean and Cryosphere in a Changing Climate produced by the IPCC

The assessment is conservative, and does not factor in the many other impacts the climate crisis has on marine life, such as ocean acidification that will impact vulnerable aquatic species.  Expanding on the investigation would therefore provide worthwhile findings that will serve to benefit the maintenance of marine ecosystems worldwide, as well as enhance what is currently understood about the dual relationship between fish species and how they reproduce amid rising temperatures.  

Climate change is doing something unusual to the fish in our oceans: As water temperatures rise, this causes fish to morph in size. Some shrink, but others grow.

How Does Climate Change Affect Fish?

In a new study published in Nature Ecology & Evolution, researchers analyzed data from more than 10 million visual survey records to understand the phenomenon of fish shrinking and growing in size in response to climate change, and to consider the effects on the marine environment and the management of fisheries.

Similar studies have tended to look at species that are commercially fished, mainly because there’s plenty of data on them. This investigation, however, looks at a wide range of fish living in the waters all around Australia.

“We looked at all species,” Asta Audzijonyte, research fellow at Australia’s Institute for Marine and Antarctic Studies and lead author of the study, told Mongabay. “The beauty of this study is that we didn’t choose any species selectively. We looked at 335 species, which were all of the species that we had enough data on, so I had that criterion as some kind of filter.

“That included tiny species … to giant fish and sharks, included species that are fished, but mostly species that are not fished, like puffer fish.”

The researchers were able to gather a large amount of data thanks to a reef monitoring program that has run for three decades, as well as a rigorous citizen science program.

“The citizen science component is the most exciting part,” Audzijonyte said. “About 100 divers … volunteered their time to collect all of this information. There was a standard method to how they do these underwater surveys: they dived and they had a transect of 50 meters [164 feet] … and they recorded all of the species they saw” within this span.

The researchers investigated size in two main ways. First, they looked at fish of the same species living in different locations around Australia, and analyzed how warmer or cooler waters in the species’ natural distribution affected their size. Second, they examined how fish species living in one location would be affected by climate change-induced warming over time.

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climate change fish size
An infographic showing differences in fish size throughout a species’ distribution. Image by Asta Audzijonyte.

Why Are Fish Shrinking in Sizes?

Changes in temperature through time, in response to climate change, had much stronger impacts on size than changes of temperatures in space, throughout the species’ natural distribution, Audzijonyte said.

“Different populations living (for a long time) at warmer or cooler parts of species natural distribution were about 4% different in body length for each degree of temperature change,” she said. “However, when water temperature changed through time in one place due to global warming, a population experiencing this warming was changing by nearly 20% for 0.5 degree [Celsius, or 0.9° Fahrenheit] of warming, observed over the last two decades.”

To Audzijonyte, one of the most surprising findings was that some fish grew, instead of shrank, in response to warming waters.

“If you looked at my earlier papers, they basically said that we expect species to get smaller with warming because that’s the generally accepted belief, and what we saw from commercially fished species,” she said.

What she and her colleagues ultimately found was that 45% of species grew in response to climate change, while 55% got smaller. Moreover, it was the bigger fish that tended to get bigger, and the smaller fish that usually got smaller.

“One of the reasons this study is important is that it shows the complexity of species’ responses to warming in our oceans,” Nicholas Payne, assistant professor in zoology at Trinity College Dublin’s School of Natural Sciences and co-author of the study, said in a statement. “Much of our understanding of the temperature-size relationship comes from the laboratory; taking our predictions to the wild shows us there is a lot we still need to learn about this hugely important phenomenon.”

The implications for these size changes are not fully understood, but these fluctuations would certainly have an impact on the marine food web, Audzijonyte said.

“As fish get smaller, they’re more vulnerable to predation,” she said. “It means that they will have a higher mortality from predators. All of these sized-based interactions will be changing quite a lot, and we don’t know what that means. We need to study that.”

This article was originally published on Mongabay, written by Elizabeth Claire Alberts, and is republished here as part of an editorial partnership with Earth.Org. 

As people around the globe stock their pantries for long stretches at home during the COVID-19 pandemic, sales of tinned tuna are going through the roof. In the U.S., consumption has increased 142% compared to the same time last year. But a new report released last month by environmental NGO Greenpeace highlights concerns about the ethical and legal credentials of many top tuna brands. The report is based on interviews with migrant fishers on three vessels operating in the Atlantic Ocean that are flagged or linked with Taiwan, including two longliners and a carrier that transports crew and fish to and from longliners. It suggests that forced labor and illegal, unreported and unregulated (IUU) fishing continue to occur within major tuna supply chains, despite efforts by companies and governments to stamp them out.

One of the vessels that interviewees accused of these practices supplies tuna to the Taiwan-based Fong Chun Formosa Fishery Company (FCF), one of the world’s largest tuna traders and the new owner of major U.S. canned-tuna brand Bumble Bee. Another of the accused vessels supplies tuna to a refrigerated cargo ship that FCF works with.

The fishers’ allegations included deception, physical violence, wage deductions, debt bondage, passport confiscation, and excessive working hours. For example, several fishers reported working 18-hour days, on average, and as many as 34 hours straight: “We only got to sleep for five hours if and when we caught some fish,” said one interviewee. “If we didn’t catch anything, we’d just have to keep working.” Crew were also transferred illegally between vessels.

The fishers also provided evidence that the vessels took part in unlawful fishing practices, such as shark finning and transferring shark fins between vessels.

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illegal tuna fishing
Tuna fish (Source: Pixabay).

Systemic Issues

Reports of human rights abuses and IUU fishing have plagued the tuna industry in recent years, and several investigations have identified the practices of Taiwanese distant-water longliner vessels as particularly problematic. In 2015, the European Commission (the executive arm of the European Union) gave Taiwan a “yellow card” for insufficient cooperation in combatting IUU fishing, warning the country that if it did not improve, it would not be able to export products from its vessels to the EU. Recently, the Taiwanese government has implemented new controls to prevent IUU fishing and reformed its fisheries legal framework in an effort to improve its products’ traceability. In June 2019, the European Commission lifted Taiwan’s yellow card in acknowledgment of these efforts.

FCF did not respond to Mongabay’s requests for comment. The company has also made considerable effort to improve its track record in recent years, including releasing a new corporate social responsibility policy and participating in two Fishery Improvement Projects (FIPs), which are multi-stakeholder efforts to improve the environmental sustainability of particular fisheries.

But Greenpeace East Asia campaigner Pearl Chen told Mongabay in an email that FCF’s efforts are insufficient and out of step with national and international standards. For example, she said the company’s policy fails to specify a guaranteed amount of rest time for crew, which is not compatible with either Taiwan’s domestic regulations or the International Labour Organization’s Work in Fishing convention. Chen also pointed out that the FIPs that FCF participates in cover only a fifth of the longliners the company sources from, so its environmental commitments don’t apply to most of its supply.

In response to a 2018 report from Greenpeace that also linked FCF to human rights abuses on longliner vessels, a company statement said, “we are … disappointed that they are implicating FCF in old incidents and cases that have since been in all instances addressed in coordination with the Taiwanese Fisheries Department.”

But the cases the new report cites are from 2019, Greenpeace senior oceans adviser Andy Shen told Mongabay. “These are fresh cases,” he said. “That’s why we wanted to let the public know — and let FCF know that we know — that this is still occurring, and it’s occurring because there are systemic issues with the Taiwanese industry.”

Lost at Sea

The distant-water fishing industry is difficult to regulate because the vessels spend long stretches in remote parts of the ocean. Instead of returning to port when they’ve fished to capacity, many longliners offload their catch onto other boats that deliver it to shore, a practice known as transhipment at sea. “So they can stay out for months or years at a time,” Shen said. “And there’s no way to check on the real conditions of workers when they’re at sea.” Greenpeace and other prominent environmental and human rights organizations have called for transhipment at sea to be banned so companies and authorities can keep better track of the fishing and labor practices on distant-water vessels. In its latest report, Greenpeace also asks companies to ensure their suppliers commit to maximum periods of time at sea and to returning to ports that have labor inspection systems in place.

According to independent fisheries consultant Francisco Blaha, a former longline tuna fisher and fisheries observer, many island countries have been pushing for a ban on transhipment at sea for years, but China, South Korea, Japan and Taiwan have consistently opposed the move. “So this is not an issue of FCF per se,” he said. “It’s an issue that goes beyond the company and it goes to the level of politics, of flag states’ relationships.”

Labor conditions are further obscured by the international nature of the workforce, Blaha said. “In the past, the flag of the vessel and the crew of the vessel were the same [nationality],” he said, “but that’s not the case anymore.” Taiwanese vessel owners often contract crew agents to recruit workers from neighboring countries, such as Indonesia, the Philippines and Myanmar. Theoretically, Taiwanese labor laws, which include a minimum monthly wage, apply to anyone working on a Taiwanese-flagged vessel. “But if [those crew agents] offer less pay than what the law says, it’s quite difficult for Taiwan to put pressure on them,” Blaha said, “especially because Indonesia doesn’t recognize Taiwan as a country.”

Shen said he would like to see companies like FCF enact policies ensuring that each vessel supplying the company is assessed for human rights violations, that each violation is addressed and measures put in place to prevent future occurrences, and that the companies publicly report on their findings to ensure transparency. “That’s a system that a lot of companies just don’t have in place, but it’s something that makes sense, and it ultimately will protect the workers and it will protect their business,” he said.

But Blaha said he thought Greenpeace’s focus on FCF was misguided. “The issue of work conditions on vessels is massive, but it’s not exclusive to one company. Of course the company has influence, because it’s a big company, but there is a limit to the influence it can have,” he said. “It’s the responsibility of the whole fisheries spectrum, from regulators, to industry, to civil society and consumers. If you point fingers at just one element you’ll just antagonize them, and nothing gets solved.”

Pandemic Planning

Shen and Blaha agreed on one thing: now is a particularly important time to spotlight the tuna industry’s fishers and factory workers’ conditions. Because food production is deemed an essential service in many countries, these employees will be under pressure to continue working as the COVID-19 pandemic spreads. “Companies need to really ensure they’re putting measures in place, including occupational safety and health measures and special protective equipment: measures to really help prevent the spread of the virus within these facilities,” Shen said.

But it will be challenging for the industry to keep up with demand in this context, Blaha said. “If you need to do social distancing in the factories, production will go down, because people there are normally working shoulder to shoulder,” he said. “And if people are getting sick, that’s fewer people on the front lines.” If production slows down, lots of fish will be lost, he said, because there’s not enough freezer capacity to store it while it’s waiting to be processed.

Fishers may also be reluctant to take observers and inspectors on board their vessels for fear of catching the virus from them, Blaha said. In fact, the requirement for purse seiner tuna boats to have 100% observer coverage has just been suspended in parts of the Pacific Ocean, in light of crews’ concerns. It’s an understandable move, but one that works against the advance of transparency in an industry that operates far beyond the horizon.

Featured image by: Daniel Case

This article was originally published on Mongabay, written by Monica Evans, and is republished here as part of an editorial partnership with Earth.Org. 


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