What Seaspiracy Gets Right About the Exploitative Fishing Industry



The slander against the Netflix documentary Seaspiracy says a lot about fishing industry influence in marine science. We have somehow allowed the fisheries industry’s own scientists to define sustainable fishing goals — it’s a disgrace leading to an ecological nightmare.

The upwelling scrutiny around Seaspiracy deflects from the greater issues it raises. (Valery Sharifulin / TASS via Getty Images)

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Ocean QAnon,” “eco-fascism,” “self-indulgent vegan propaganda” — fishing industry scientists are angry about Seaspiracy, the new Netflix special topping charts around the world, which details the impact of industrial fishing on marine life and the complicity of certification labels and even some ocean conservation groups. The controversy swirling around Seaspiracy seems to center around statistics, but beneath the surface lurk deeper questions about industry influence in marine science.

Seaspiracy is not without its faults. Its interview style is abrasive. It has excessive animation. It makes a couple of statistical misinterpretations and several oversimplifications. Yet the film is mainly accurate and devastatingly detailed, provoking viewers around the world to question the industry values that have become integral to marine science orthodoxy: Why do we call fish populations “stocks”? What does it mean to call them “under-fished”? How do they calculate maximum sustainable yield? Is it really sustainable?

The academy’s response to Seaspiracy was swift, stern, and sloppy. Although allegedly leaked documents show that groups like the National Fisheries Institute were preparing a media response for weeks, the industry-funded Sustainable Fisheries, University of Washington’s fact-check page falsely claimed that one of the film’s source studies — estimating 20-32 percent of marine life imported to the United States was caught illegally — had been retracted. Ironically, they had to retract the claim. Sustainable Fisheries UW correctly questioned a sea turtle bycatch statistic, for which Seaspiracy repeated a mistake made on a Sea Turtle Conservancy white paper. Even though fisheries scientists tracked down the source study, they didn’t seem to read the abstract, which revealed that the near-global figure was misattributed to the United States. Instead, they attacked its credibility, revealing the modus operandi of fishing industry public relations.

It’s fair to say that Seaspiracy cited some studies that can be considered dated or disputed, but it also left out some of the most harrowing statistics published in recent years. The most current worldwide analysis estimated the bycatch of at least 8.5 million sea turtles in a seventeen-year period. Catch reconstructions show total fish hauls as peaking in 1996 and declining ever since, despite exponential industrialization and permeation of fishing fleets. A global investigation of navigation patterns estimated up to a quarter of fishing vessels may have forced labor on deck.

The most controversial statistic in the film is the projection of global crashes in commercially exploited fish populations by 2048. What the industry doesn’t mention is that they generated the controversy. Since the 2006 publication of “Impacts of Biodiversity Loss on Ocean Ecosystem Services” in Science magazine, industry groups have doggedly scolded media outlets for citing it. Professor Ray Hilborn, who founded Sustainable Fisheries UW, emerged as this study’s most prominent critic. A decade later, he would be exposed for not only receiving millions of dollars in seafood industry funding but failing to disclose it as a conflict of interest. While he did work with the author of the 2048 projection on a subsequent paper, this research didn’t correct or disprove its conclusions but rather cited them.

The lead author on both studies is a conservation biologist named Boris Worm, who said fisheries scientists’ cooperation on the second made him “somewhat more optimistic” but explicitly stated that the work “did not revisit the original projections.” When he finally did so in 2016, he clarified that updated models were less ominous but remained “sobering.” Hilborn nevertheless continues to crusade on behalf of industrial fishing, publicly advocating against marine reserves and providing testimony to lawmakers on the dangers of “under-fishing.” His foundation’s Seaspiracy response disputes four statistics out of more than one hundred, all of them by downplaying the degree of the problem and criticizing colleagues’ research, begging the question: Is the film full of errors, or does it just upset the industry?In essence, we have allowed fisheries industry scientists to define sustainable fishing goals, somewhat like allowing petroleum geologists to set emissions targets.

The enduring controversy over the 2048 projection is emblematic of a much deeper rift in marine science, between those who view fish as wildlife to be protected versus resources to be extracted — namely conservation biology versus fisheries science. While conservation biologists aim to restore fish populations, the explicit goal of fisheries science is to repress their recovery. The simplistic modeling formulae upon which modern fisheries science is founded defines the population level of maximum sustainable yield as half of a fish population’s carrying capacity. In theory, this strikes a balance between reproducing individuals and limiting factors where maximum population growth — and, conveniently, maximum profitability — will occur.

This means that when the UN Food and Agriculture Organization says that two-thirds of “fish stocks [are] within biologically sustainable levels” (disputed in itself), this means that most of these populations are at approximately half their historical levels, with the remaining third lower yet. Below 40 percent, populations are classified as overfished — in the United States, however, the threshold is 25 percent. Anything above 60 percent carrying capacity is defined as “under-fished.” This philosophy is not only markedly errant from fishing practices sustained for millennia by indigenous cultures but has become one of the greatest threats to their subsistence. In essence, we have allowed fisheries industry scientists to define sustainable fishing goals, somewhat like allowing petroleum geologists to set emissions targets.

However, fisheries scientists weren’t the only academics to decry Seaspiracy. While received rather differently by marine biologists around the world, these industry paradigms run deep in American academia. Sylvia Earle and Callum Roberts, the marine biologists Seaspiracy consults, represent marginalized ideologies and receive criticism for valuing fish as wildlife, as Dr Earle puts it, arguing that our goal should be to minimize, not maximize, their extraction. This advocacy got her locked out of meetings as the first female chief scientist at the National Oceanic and Atmospheric Administration, advising the regulatory body formerly called the National Marine Fisheries Service — now NOAA Fisheries — of which she says the “primary purpose is to serve the interest of commercial fishing.”

While the pointed message of the film has inspired a reflection on these values among average viewers, it seems that academic institutions, in fisheries science and marine biology alike, may be some of the last to consider them. At least that’s how I felt after a summer researching at UW.

“Looks like we’ll have another urchin-cracking party,” my principal investigator chuckled, planning another student’s study on urchin gonad contents. My eyes widened as I realized she was talking about “my” urchins, whose feeding behavior I was studying in tanks down the road. They were wild-captured giant red sea urchins — Strongylocentrotus franciscanus — the biggest species in the world. They can grow to twenty-one inches from spine to spine and live for perhaps two hundred years. Some of these urchins may have walked the seafloor below the bustling canoe fleets of the precolonial Salish nations. Many were likely older than me. I wanted to set them free but was hesitant to object, as this research project was a critical opportunity for me to build connections and obtain references for grad school.

As I loaded up the urchins near the dock, the marine lab’s program director approached me. I waved nervously. “Thank you,” she said, in her thick Senegalese accent. She told me of prestigious urchin researchers she’d seen in her career simply leave captured urchins in stagnating tanks to die in the sun. “Of course,” I replied. She must not have heard that there were other plans for them. As I reached the other side of the channel and cut the engine, I pulled out a plastic drum brush and began tickling the urchins’ tube feet until they let go. I leaned over the gunwale, placing them carefully in the water and finally came to my favorite — Houdini. I was never quite able to design an enclosure capable of containing that one.

Watching the little urchin slowly disappear into the depths of Puget Sound, I couldn’t help but smile, rediscovering what I had always known yet learned to forget: marine life is wildlife.

The upwelling scrutiny around Seaspiracy deflects from the greater issues it raises. Life on Earth began in the sea, and human life has always been bound to it. We must protect our ocean, using all strategies at our disposal, and collectively reclaim the authority to govern how it is treated from those who profit from its exploitation.

Seaspiracy: What the Fishing Industry Doesn’t Want You to Know

ByMatthew ChalmersMarch 31, 2021

Adam Lau / Sea Shepherd Conservation Society


Several days before Seaspiracy was released on Netflix, a response made by the National Fisheries Institute was leaked. Before audiences had gotten a chance to see the documentary, the fishing industry was already dismissing it as “vegan propaganda.” Unfortunately, it is unlikely that their opinion of the film emerged from any genuine Delphic foresight. Indeed, “propaganda” seems quite a puzzling label to stick on a movie that unravels its story in such a deliberate and reasoned manner.

The facts in the documentary are nothing short of remarkable. A marine biologist explains that the Deepwater Horizon Disaster, which spilled thousands of gallons of oil into the sea and saw countless images of seabirds coated in black, dying on slimy beaches, killed fewer animals than commercial fishing in the Gulf of Mexico kills in a single day. Indeed, the disaster actually allowed fish stocks in the Gulf to bounce back because it interfered with normal fishing operations. Other numbers in the film are so big they really can’t be comprehended, like the fact that humanity kills five million fish every second.

Lex Rigby, the head of investigations at Viva!, explained the apathy most people feel towards fish. “Whenever we talk about fish, we talk about harvesting them like crops,” she said. “We talk about their slaughter number in tonnage rather than individuals.” Perhaps this is one place Seaspiracy is a touch lackluster; it doesn’t dwell for long on the evidence that each fish is an individual with a distinct psychology, no matter how remote their experience is from ours, which can feel pain.

However, the movie does illustrate the troubling ways in which commercial fishing has been sidelined as an issue, even by the environmentally-conscious. Plastic is the favored bogeyman when it comes to ocean pollution, and it certainly is a serious problem. Yet popular talking points, like the murderous flotillas of plastic straws, are more or less total canards. Plastic straws make up 0.03 percent of ocean plastics, and all plastics combined kill roughly 1,000 sea turtles a year. Fishing, on the other hand, kills 250,000 sea turtles a year. Similarly, the origin of the plastic is often imagined to be apathetic consumers who purchase thirty plastic bags every trip they make to Walmart, and yet 46 percent of the Great Pacific Garbage Patch is made up of fishing nets. These nets drift through the open ocean for miles, tangling and strangling thousands of animals as they go, and are far deadlier than plastic bags.

It is not an accident that fishing has been neglected in discussions about ocean conservation either. The issue has been obscured by specious labeling and a culture of omertà amongst governments and regulators. The Earth Island Institute relies on captains’ self-reporting when they hand out their dolphin-free labels, which is an obviously poor standard of evidence. Rigby described the way self-reporting is abused by fishing vessels, drawing from her time with Sea Shepherd off the coast of West Africa, “We counted one hundred and seventeen sharks in one net. They only reported four.”

The Marine Stewardship Council, whose ubiquitous blue tick assures millions of consumers that they are purchasing vetted and sustainable seafood, seem to have included the word ‘stewardship’ in their title as some sort of bad joke. The more blue ticks they hand out, the more money they make, and one of their founding members was the food (including seafood) giant Unilever. Additionally, the world’s sustainable fisheries are proved to be anything but, seeing as 90 percent of them continue to allow commercial fishing.

Those invested with the powers of stewardship neglect them. Citizens are left in the dark with misleading labels and glib talk about sustainable fishing for a comfort blanket, while the oceans are scraped and pillaged. Aquaculture, like salmon farming, is not a sustainable alternative to wild fishing, although it is promised to be. Salmon are fed wild fish, with 1.2 kilograms of wild fish producing 1 kilogram of salmon. The farms are teeming with lice which feed on the salmon while their accumulated waste creates zero-oxygen dead-zones.

Like all great explorations of ecology, Seaspiracy highlights the dramatic intersection between animal wellbeing, environmental health, and human prosperity. European and North American fishing fleets scouring the coasts of Africa drive local fishermen to bushmeat hunting, which causes pandemics like Ebola, or piracy, as happened in Somalia. Rigby described these local fishermen as “really the only sustainable fishing there is, just one man and his net pulling up enough to feed his family.” It is these sustainable communities which industrialized seafood has ruined; and they aren’t the only ones. Indeed, mangroves are cleared at the peril of locals, who are made vulnerable to tsunamis and typhoons, and the shrimp farms that replace them are often exploited by slave labor. 

The documentary finishes with a famous event on the relatively obscure Faroe Island archipelago. Communities there participate in whale hunts, called Grindadráp, where locals round up pilot whales on boats before harpooning them en masse in the shallows. It is a gory and relentless scene, and the sea sloshes in Biblical reds under grim and misty cliffs. Here, the movie sticks the landing. Sustainable fishing has been discredited and the severity of human pillaging of the oceans has been put beyond doubt. Yet, even if these things could be managed, the film begs us to question if it would be worth it. It questions if fish and chips are really worth killing for, if dead whales soaking in a Norse lagoon is an acceptable sight in a world where kinder, greener and healthier alternatives exist. Such disturbing spectacles are by no means unique to the Faroes; one articulate whaler in the documentary points out that suffering is universal in global meat and fish production. Rigby described disturbing scenes from her own experience, from endangered whale sharks scooped up in nets in Africa, to lice-ridden salmon suffering on Scottish farms.

In 90 minutes, the film provides helpful graphics, illustrations, anecdotes, filmed evidence, mountains of data, and the opinion of scientists and ethicists to make its point. It doesn’t shrink from violence, nor does it fetishize it. The arguments are concise and plainly presented. Yet all this can be waved away by the magic wand of the fishing industry and fellow travelers as “vegan propaganda,” and well before the movie is even released. Remind me again who the propagandists are?Read More

Corporate Corruption in Global Fishing Gets New Attention

Fish Farming Is Not As Sustainable As We Thought

Commercial Fishing: How Global Food Choices Negatively Impact the Oceans

Criticism of Seaspiracy is Much Ado About Nothing

It’s Time to Make a Big Deal About Something And That Something is the Dying Ocean..

By Captain Paul Watson.

Predictably, the successful release of Seaspiracy on Netflix is receiving some criticism from the usual subjects. That was expected, but it really is not all that important. Many documentaries that I have been involved with over the years have been met with similar negativity and vitriol. I remember the criticisms of Rob Stewart and his wonderful film Sharkwater. And The Cove also was belittled by some although the criticisms did not prevent the film from winning the Academy Award for best documentary of the year. Sea of Shadows was also belittled as was even my own film WATSON by Leslie Chicott and I do remember Lesley’s earlier film Inconvenient Truth and all the climate change denialists with their hired “scientist” apologists lambasting the credibility of Al Gore. And don’t even get me started on all the “experts” denouncing Greta Thunberg for being too dramatic, too, young, and too naïve for their taste. Seaspiracy as a film is what it is, a message transmitted by a medium to provoke discussion and to expose and illustrate a global problem and as such it is both powerful and influential and most importantly thanks to Netflix it is reaching millions and trending phenomenally. It was never meant to be some academic scientific dissertation filled with footnotes and boring references to peer reviewed papers. It’s a film, not some doctoral thesis to be picked apart in search of validation to justify a particular bias.

If we were to produce a 90-minute film with a purely objective scientific fact confirmed narrative as suggested, it would most likely not appeal to the general public and nothing would change. The corporations and those who work for them already know the facts. They just don’t care because they are motivated by profit.Film making is story telling. It’s meant to be emotive. It’s designed to captivate viewers and to entice discussion and controversy. If people are talking about it that means it’s a success. If people are criticizing it, that means it is having an impact. If some people are condemning it, that means that some people are threatened by it.Personally, I don’t care if there are scientists and industry people who dislike the film. I don’t need biostitutes and P.R. firms to lecture me on something I have seen and witnessed with my own eyes over the last 60 years. There is no such thing as a sustainable fishery. That is my considered observation based on 60 years of experience. Phytoplankton populations in the sea have been reduced by 40% since 1950 and that is probably the most important validated scientific fact to be concerned about. (Source: https://www.scientificamerican.com/…/phytoplankton…/

Life in the Ocean is being diminished and that diminishment is escalating. I’m not surprised that there are many who wish to deny this just as there have been many quick to deny climate change.Change comes about through stories and in today’s world, the most powerful communication medium is film. Lucy and Ali Tabrizi are telling an important story and it’s a great deal to tell in a mere 90 minutes. I would have liked to have seen more details, but more tends to be difficult when making a film because there always tends to be too much material and too little time. Seaspiracy is a hit and it is reaching millions and Ali and Lucy Tabrizi have done a wonderful job in a project that I have actively been involved with for the last few years and proud to be associated with as I’m sure Captain Peter Hammarstedt and Dr. Sylvia Earle are as well. Fisheries consultant Francisco Blaha amusingly generalized the filmmakers by stating that the film has a tendency to generalize. He tweeted, “I’m over the set up where the ‘bad guys’ are predominantly Asian, the ‘victims’ predominantly black/brown, and the ‘good guys’ talking about it and saving the ocean are predominantly white.”Blaha admits in a tweet that he actually did not see the entire film and his bias is apparent in his job title as “fisheries consultant” to industrialized fishing corporations. In the film the bad guys are not predominantly Asian. The film focus is on European as well as Asian fishermen and shows how artisanal fishing communities in Africa are being devastated by industrialized fishing. Industrialized fishing corporations are the bad guys. His assertion that those in the film are predominantly white males is also incorrect. The film was made by a man of Middle Eastern background and a woman – Lucy Tabrizi and features the voices of Dr. Sylvia Earle, Dr. Jane Hightower, Tamara Arenovich, Lori Marino and Lamya Essemlali amongst others. As for Sea Shepherd, we are working hand in hand with African and Latin American nations to oppose Asian AND European exploitation of the waters of these nations. We are in fact working with and for African and Central and South America nations. This means we are working in opposition to the industry that Blaha consults for. In 2019, Blaha was the winner of the 2019 World Seafood Champion Award which is all we need to know to understand his bias

This film by Ali and Lucy is their project, it is their voice and they have every right to tell their story the way they wish to tell their story. If the critics don’t like it they should take up the challenge and make their own film. In fact, that is the only valid response. All this chatter and pooh-poohing of a film they happen to not like is irrelevant and meaningless.If they want to make a film with what they consider to be “real” science they should do it. It’s easy to be a critic, easy to slam the work and creativity of others. If there is a film they would rather see produced, one that meets with their approval they should just shut up and make it.

Farley Mowat wrote and made a TV series Sea of Slaughter a few decades ago. Solid science it was indeed yet it was dismissed by industry and restricted to the limited audience of the CBC and he was also told that he was not delivering his message properly meaning he should be doing it by not offending anyone. He warned us years ago about what was happening yet nothing changed and things became much worse.

This film despite the naysayers and the critics is a critically acclaimed success and that is a fact. It is a weapon of revelation and it is influencing millions and it needs to be built upon and not dismissed or belittled, especially by people who profess to care about marine ecology. The Ocean does not have time for the justifiers, the appeasers and the complainers. Right now, the Ocean needs activists more than scientists.https://www.ecowatch.com/commercial-fishing-netflix…

The next frontier for animal welfare: Fish


Fish are farmed in higher numbers than any other animal, but they haven’t gotten much attention from the animal welfare movement — until now.By Kenny Torrella  Mar 2, 2021, 9:30am EST

Young salmon swim in a pool. Salmon are one of the most commonly farmed fish species.

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The way we eat now, and the food system that makes it possible, is so relentlessly grim for animals that it’s easy to forget that much progress has been made in the fight for their well-being.

In the early 2000s, no US states had laws on the books regulating the welfare of farmed animals. Now, a dozen do. Back then, fast food chains and grocers hardly considered the treatment of chickens and pigs in their supply chains. Now, hundreds have pledged to source higher-welfare meat and eggs. And it’s safe to say that the new generation of plant-based meat has been embraced by the mainstream.

Animals do still have it awful on factory farms, but it’s fair to argue that over time, our moral circle has expanded.

But one animal raised and killed in higher numbers than any other hasn’t quite become encompassed in that growing moral circle: fish.

Manyanimal welfare advocates consider fish farms to essentially be “underwater factory farms,” where fish are overcrowded in tanks, generally grown in terrible conditions like factory-farmed chickens, increasing their stress and susceptibility to disease.

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It’s unsurprising that fish have been ignored. They live underwater, so we rarely interact with them. They can’t vocalize or make facial expressions, so it’s much harder to understand them than mammals and birds. And research has shown that the further animals are from us on the evolutionary chain, the less likely we are to try to protect them.

But as momentum grows for better treatment of farmed animals, we need to make sure that fish aren’t left behind. Continuing research into fish pain has given us greater insight into them than ever before — and has bolstered the moral case for caring about fish. Beyond the moral case, there’s an urgent environmental case to be made not just to improve fish welfare on farms but to scale back on fish farming altogether. That’s because over the course of their short lives, most farmed fish are fed anywhere from a few to over a hundred wild-caught fish — depleting fish species that play important roles in our oceans.

For advocates, the successes of the anti-industrial farming movement provide a road map. “We can learn from [the animal welfare movement’s] past successes and failures, and go from there,” Haven King-Nobles, a co-founder of Fish Welfare Initiative (FWI) — a new organization that advocates for higher animal welfare standards in the fishing industry — told me.

In January, FWI announced a project in India (ranked third in global fish farming) that could improve the welfare of several million farmed fish each year. The group plans to work with Indian farmers to improve water quality and set caps on how many fish can be kept in each tank or pond, among other changes. At the same time, investors are pouring millions into startups working to make plant-based and lab-grown, or cell-based, fish.

Industrial fish farming is a hugely consequential part of our food system. Yet it has received a fraction of the attention in our discussions on fixing the global food machinery. That needs to change.

Fish farming, explained

Industrial fish farming, or aquaculture, is relatively new. Humans have farmed fish for millennia, but it wasn’t until the mid-20th century that we saw industrial fish farming take shape, and it wasn’t until the 1990s that it really took off. Now we eat more farmed fish than wild-caught fish, and about 90 percent of them are farmed in Asia, primarily in China, Indonesia, India, and Vietnam.

In recent decades, fish farming has taken off as the fastest-growing sector of the food industry. We now eat more fish from farms than caught in the ocean.

We don’t have good data on how many fish are farmed or caught in the wild, since fish production is measured in weight, not the number of fish farmed or caught. Estimates of farmed and wild-caught fish vary, from hundreds of billions to trillions total, and there’s even a website dedicated to trying to figure this out. While the number of fish caught in the wild hasn’t changed much over the past few decades, fish farming has become one of the fastest-growing sectors of the food industry.

The rationale put forward for fish farming is simple: It’s a solution to overfishing. Populations or “stocks” of fish in the wild are thought to be overfished when so many are caught that their numbers plummet and they can’t recover fast enough. It can disrupt delicate marine ecosystems, not to mention decimate fish populations.

But some researchers think fish farming isn’t actuallydoing much to conserve wild fish populations, and may be perpetuating the problem it was supposed to solve, since farmed fish are fed a lot of small wild-caught fish (in the form of fishmeal and fish oil) — what anNPR report dubbed the “fish eat fish” chain.

The number of wild-caught fish needed to raise one farmed fish varies, depending on whether the species is carnivorous, omnivorous, or herbivorous. For example, farmed Atlantic salmon are fed about 147 “feed fish” throughout their lives, whereas Nile tilapia are fed about seven. There are efforts to ameliorate this problem by using less fishmeal and more plants in farmed fish diets and shifting production to more omnivorous and herbivorous species, but the problem persists: A 2019 report found that about one-fifth of all wild-caught fish are turned into fishmeal and fish oil to feed farmed fish.

Then there are the animal welfare problems associated with fish farming.

In commercial ocean fishing, the welfare concerns are mostly relegated to the final minutes or hours of a fish’s life — they’re typically left to suffocate to death on deck, which can take under an hour or up to several hours. (Dylan Matthews did a podcast on a more humane way to slaughter caught fish.)

In fish farms, a different fate awaits the animals.They suffer for months, and for some species over a year, before they’re slaughtered. Fish farms come in many setups — some are tanks that look like big aboveground swimming pools, some are in ponds, and others are set up as offshore cages. But whatever the type of farm, three of the biggest welfare problems are the same as those on factory farms on land: overcrowding, disease, and rapid growth.

To get as much meat as possible in as little space, farmers cram a lot of fish into their tanks and pens, just like chickens in a barn. Overcrowding in fish farms can lead to poor water quality (from fish waste and antibiotic usage), higher injury rates, increased aggression, and susceptibility to disease. (Here’s a good overview of welfare issues in fish farms.) GRID VIEW

1 of 5A sturgeon farm at the Da Mi hydroelectric resovoir lake in Tanh Linh district, Vietnam’s central southern province of Binh Thuan. Hoang Dinh Nam/AFP via Getty Images

Poor water quality can also compromise fishes’ immune systems, which means more fish will get sick or die when disease spreads. One common problem found on fish farms is sea lice infestation. Sea lice are parasites that cause painful lesions on fish and are typically treated with harsh chemicals that further degrade water quality and fish health. When sea lice infect fish farms set up in offshore pens, those chemicals can leach into larger bodies of water and kill off other marine life.

Chickens have been bred to grow so fast that they’re in constant pain, and similar breeding practices have been used to develop fish that grow much faster and bigger than they normally would, which can cause health problems like increased incidence of cataracts and abnormal heart shape and function.

Another problem wrought by breeding fish to grow faster and bigger is “genetic pollution.” Since the 1970s, tens of millions of farmed salmon have escaped into the wild, and when those farmed salmon breed with wild Atlantic salmon populations, they spawn new, “genetically polluted” fish that are less likely to survive in the wild and are reproductively inferior compared to wild salmon.

Other welfare issues include rough handling and the inability to express natural behaviors, like migration and nesting.

The fish pain debate

A big obstacle to fish welfare has been the question of whether fish feel pain. For decades, the thinking went that because fish lack a neocortex — the part of the mammalian brain that processes sensory perception, consciousness, spatial reasoning, language, and motor commands — they are not conscious, and thus can’t feel pain.

But in the early 2000s, a group of researchers at the University of Edinburgh — Lynne Sneddon, Victoria Braithwaite, and Michael J. Gentle — set up a research program to test that assumption.

In one of their experiments with rainbow trout, the researchers dropped Lego blocks into a tank to see how the fish would react. Normally, trout would avoid novel objects like Lego blocks out of fear. But when injected with a shot of acetic acid, the trout were less likely to avoid the Legos, as they were focused more on their own pain than avoiding a potential threat. When injected with both the acid and morphine, the trout avoided the blocks as they typically would.

In another experiment, the researchers found that when they injected the lips of rainbow trout with acetic acid, the trout would rub their lips against gravel rocks or the side of the tank, the way we might rub a toe when we stub it.

Their early work on fish pain inspired others, and there are now labs around the world that have built up a large body of research concluding that fish do in fact feel pain. One of the bigger findings of the past two decades has been that fish have nociceptors, sensory neurons that detect and respond to damaging or threatening stimuli — a strong indicator they experience pain. Sneddon, one of those early fish pain researchers, says the biology of the nociceptive system of fish is “strikingly similar” to that of mammals.

There are still some skeptics. One of the more outspoken is Brian Key, a professor of biomedical sciences at the University of Queensland in Australia. In an email, Key told me that “fish just don’t have the brains for pain.” He says that in experiments that supposedly demonstrate fishes’ capacity for pain, fish are just automatically reacting to harmful stimuli but that their brains don’t register it as pain the way ours do.

But Key is an outlier on this question. Dozens of researchers responded to his 2016 paper “Why fish don’t feel pain,” most of them in disagreement with his conclusion.

“We now know that fish have changes in brain activity in relation to potentially painful events that are different from non-painful events,” Sneddon told me when I asked her about fish pain skeptics. “In my opinion, research shows beyond a reasonable doubt that fish experience pain.” She also pointed out that the skeptics have only published reviews and opinion pieces — they haven’t conducted experimental research.

Much of the debate comes down to the simple fact that we can’t ask a fish — or a dog, or a chicken — how they’re feeling. But just like with other species, researchers have repeatedly demonstrated that fish behave differently in adverse conditions (for example, they limit eating and activity) and stop these behaviors when pain relief is given.

The emerging fish welfare movement

This consensus among scientists has begun to trickle into policymaking. The World Organization for Animal Health, an intergovernmental agency that sets minimum (though non-enforceable) animal welfare standards for member nations, published recommendations on fish slaughter in 2015. A couple of UK supermarket chains have set modest animal welfare standards for the fish they sell. And last year, the European Union’s Platform on Animal Welfare set fish welfare standards for the European Commission to consider.

These largely modest and symbolic developments are setting the floor for fish welfare, but aren’t as far along as the animal welfare standards for farmed birds and mammals (which are also far from perfect).

One reason for this delay in protections is the sheer complexity of fish production.

The factory farming of land animals is pretty uniform; a few kinds of animals are farmed, and an egg factory farm in the US is going to look pretty similar to an egg factory farm in India, or just about anywhere.

But there’s much more diversity in fish farming — many more species (and thus different welfare and dietary needs) and many more types of farming setups.

Despite these challenges, in the past two years, some older animal welfare organizations have made efforts to change things and have begun to document conditions inside US fish farms. And two new groups have formed to take up the issue — the aforementioned FWI, and the Aquatic Life Institute.

FWI plans to keep building relationships with farmers in India and other countries that farm a lot of fish, and hopes to work more collaboratively with the fishing industry, compared to the mostly combative relationship between the animal welfare movement and the egg, pork, dairy, and chicken sectors. “We have a blank slate for this movement, and I see potential for us to start on a good note with industry,” King-Nobles of FWI told me. “There’s talk about welfare in the industry already, and it’s not even demanded or fought for by people like us.”

Fish Welfare Initiative’s managing director, Karthik Pulugurtha, visits a fish farm in Andhra Pradesh, India.

Aquatic Life Institute (ALI) looks to fill other gaps. One area where it sees a lot of promise is in working with seafood certification programs, most of which look at environmental concerns and not animal welfare. ALI scored its first win in late 2020 when Global GAP, a seafood certifier with 2 percent market share, agreed to adopt some of its recommendations to improve fish welfare.

ALI also sees opportunity in working with researchers and industry to change the composition of fish feed. As noted earlier, much of the food fed to farmed fish is actually wild-caught fish, and ALI wants to make more fish feed fully or partially plant-based in order to reduce the overall number of fish caught in the wild.

Animal welfare advocates in Asia are also beginning to address fish welfare, though the movements there are still relatively small.

Last month, the Federation of Indian Animal Protection Organizations released the results of its investigation into 241 fish and shrimp farms and reported high levels of lead and cadmium in fish farms, high use of antibiotics, and poor animal welfare. Varda Mehrotra, the group’s executive director, told me in an email that the group plans to use its extensive findings to push for changes in the nascent and largely unregulated Indian fish farming industry.

The Environmental & Animal Society of Taiwan has campaigned for fish, too, and organizations across Europe have started to investigate fish farms.

Growing interest in plant-based and cell-based fish

If the fish welfare movement is coming on a bit late, especially compared to other animal welfare campaigns, it’s not quite as behind when it comes to producing plant-based fish meat.

At present, there are more than two dozen startups developing plant-based or cell-based fish with a lot of investor interest. Last month, BlueNalu, a California-based startup growing fish from cells, raised $60 million (the biggest funding round yet for cell-based fish) to advance its regulatory review with the Food and Drug Administration and open a pilot production facility.

Close-up of BlueNalu’s whole-muscle, cell-based yellowtail, beer-battered and deep-fried for fish tacos.

There’s still a long way to go. Beyond Meat and Impossible Foods are getting pretty close to making plant-based beef that tastes like the real thing, but plant-based fish startups are still far from nailing the taste of fish.

However, there is a lot of interest from the traditional seafood industry to narrow this gap. Thai Union, a major global seafood producer, was an investor in that recent round of funding for BlueNalu, and the company also plans to sell its own plant-based shrimp this year. Bumble Bee Foods, an iconic US seafood brand, has a distribution partnership with Good Catch, a plant-based fish startup. And VHC, another major fish company, has formed partnerships with a lab-grown fish company (Avant Meats) and a plant-based fish company (New Wave).

Industrial fish farming has become a dominant force in the food industry in just a few decades, recreating some of the environmental problems it was supposed to solve and creating a whole new set of animal welfare issues. But considering the progress made for farmed mammals and birds, there’s every reason to think the fight for fish welfare will become part of the anti-industrial farming movement. It’s the obvious next expansion in humanity’s moral circle, and it will gain even more momentum as the next generation of meatless substitutes gain purchase with consumers the world over.

Episode 21: Fish, the Forgotten “Food” Animal with Mary Finelli of Fish Feel

26 February 2021

Banner with Hope Bohanec holding a chicken
Mary Finelli

Just as United Poultry Concerns was the first farmed animal advocacy organization to focus on chickens, Fish Feel was the first organization to focus on fishes. In Episode 21 we have a special interview with Mary Finelli, founder and president of Fish Feel. Hope and Mary discuss how fishes are caught and killed in the ocean by the trillions every year and how the fishing industry is also notorious for human slavery.

Mary talks about aquaculture and the cruelties to the fish in this industry as well as the ecological damage caused by fish farms. She shares her insights into the killing and eating of other marine life such as lobsters, crabs, oysters, and clams and also educates us on the fish oil supplement industry, the caviar industry, and the exciting new trend in advocacy of fish rescue. Listen in for a breadth of knowledge about our underwater relatives and share this episode with those who need to hear it.


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United Poultry Concerns


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Machipongo, VA 23405 USA

Will Live Fish Be Left to Suffocate and Die in Blair County, Pennsylvania?


Concerned Blair County, Pennsylvania, residents have contacted PETA regarding the fates of fish and other aquatic animals whose lives hang in the balance as the lake at Lakemont Park, reportedly owned by Blair County, is drained so that sediment can be removed. According to news reports and eyewitnesses, the water level has already been dramatically lowered and the fish who remain are struggling to survive in the shallow water. Many other aquatic animals also call the pond home, including large turtles. All these animals face a horrifying death by suffocation or desiccation if they are not rescued. A group of local residents have banded together and appear willing to undertake all the work and expense necessary to relocate the animals to private ponds (state law prohibits relocation to state-owned waterways), but the agencies in charge have apparently refused to grant permission for the rescue to take place.

PETA contacted the Blair County Conservation District, whose representative claims that a plan is in place to remove the fish, but the representative refused to elaborate further regarding this plan or to explain whether a plan existed to help the turtles and other species. This is especially concerning since Pennsylvania Fish and Boat Commission officials apparently feel that allowing the fish to die and rot on site—or throwing the animals into a “dead hole”—is an acceptable plan!

These animals desperately need your voice now! Please contact decisionmakers and urge them to take immediate steps to ensure that the fish and other aquatic animals in the lake at Lakemont Park are treated humanely. Let them know that under no circumstance is it acceptable to allow these sentient animals to suffocate or desiccate, particularly when humane alternatives exist.

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Dramatic double discovery of a fish on the brink of extinction


Dramatic double discovery of a fish on the brink of extinction
River phoenix – A precious juvenile ship sturgeon, risen from the depths. Credit: Irakli Tsulaia

Within the space of less than a month, two specimens of a vanishingly rare fish have been plucked from the waters of the Rioni River in Georgia.

Before these two juveniles were caught, conservationists had expressed fears that the critically endangered ship  might have already sunk without trace. This extraordinary, other-worldly fish—whose evolution dates back hundreds of millions of years—had not been seen alive in the wild for many years.

A lack of solid scientific research on the species means that very little is known about the ecology and distribution of the ship sturgeon, but no one disputes that it is in deep trouble. In that context, the capture of two juvenile fish in quick succession, each estimated to be less than three years old, is extremely exciting news, raising the prospect that this elusive and gravely imperiled species might still be reproducing in the Rioni.

Sturgeons were once widespread throughout Europe, but have been virtually wiped out by a lethal combination of overharvesting, poaching and the loss of traditional spawning grounds to habitat destruction. The Rioni is one of the last three remaining refuges of these dwindling denizens of the Danube and the continent’s other great river systems. Remarkably, it still harbors breeding populations of several sturgeon species.

Georgia on our minds

The first evidence of recent reproductive success came in 2018, when a tiny —tentatively identified as a stellate sturgeon—was caught by two female students working  for Fauna & Flora International (FFI) on a  launched earlier that year in an effort to safeguard Rioni’s remaining riches.

Dramatic double discovery of a fish on the brink of extinction
Sturgeon spawning grounds in Georgia’s Rioni River. Credit: Fleur Scheele/FFI

Since conducting what were the very first baseline studies for sturgeons in Georgia, FFI and our in-country partners have set about combating the threats to their survival, in particular poaching and illegal trade. We have established monitoring teams comprising ‘citizen inspectors’ drawn from communities along the river, whose role is to inform governmental agencies about incidences of poaching. FFI works closely with these communities—from schoolchildren to fish traders—to raise awareness of the plight of the sturgeons in the Rioni—and their global importance.

The FFI research team continues to work on the river from early spring to autumn, gathering vital data on sturgeon recruitment and genetic diversity in Georgia’s territorial waters. In collaboration with Ilia State University, we collect samples from any captured sturgeons for genetic analysis, in order to aid identification and shed light on which species still survive in the Rioni.

Hook, line and sturgeon

Ironically, both ship sturgeons were accidentally captured by surprised anglers, the first in mid-March, and the second just three weeks later. All sturgeon species in Georgia are officially protected, and commercial fishing on the Rioni is severely restricted, but sport fishing with rod and line is permitted, provided that anglers release any sturgeons they catch.

The fact that both anglers contacted one of FFI’s citizen inspectors immediately after catching the juvenile sturgeons—thereby enabling photographs and samples to be taken before the fish were returned to the river—is a success story in itself, vindicating FFI’s efforts to engage with nearby communities and engender local support for the project.

A week after the second ship sturgeon was caught, the river yielded a third juvenile, this time captured by the FFI team and provisionally labeled as a Colchic sturgeon—although hybrids are known to occur and can be difficult to differentiate from the real deal without detailed analysis.

While the ichthyologists may be agonizing over the idiosyncrasies of sturgeon subcategories, one thing is certain: the latest revelations provide further irrefutable evidence that the Rioni is an absolutely crucial sanctuary—and possibly the last hope—for these armor-plated icons of the fish world.

Dramatic double discovery of a fish on the brink of extinction
Another juvenile – believed to be a Colchic sturgeon – completed the trio of young fish caught within the space of a few weeks. Credit: Tamar Edisherashvili/FFI

Dammed to extinction?

Further studies will be required before we can confirm categorically that the ship sturgeon is still spawning in Georgia’s mightiest river, but it seems that there could be light at the end of the tunnel. Unfortunately, that glimmer of hope is in imminent danger of being snuffed out.

A significant new threat to the survival of Georgia’s sturgeons has recently surfaced. The proposed development of several hydropower plants upstream from our project site could have a potentially disastrous impact on the Rioni—and put paid to the recovery prospects of its flagship  species.

We risk having to bear witness to the tragedy of a rediscovered species being pulled back from the brink of extinction by conservationists only to be knowingly pushed over the precipice in the name of economic progress. Let’s hope that day never arrives.

Explore further

Little fish, big deal – Baby sturgeon offers hope for the future

This fish is ‘king of the reef.’ But high-end diners may change that.

The luxury live reef fish market threatens the humphead wrasse. Could its unique “eyelashes” help save it?
7 Minute Read
By Danielle Beurteaux

PUBLISHED March 20, 2020

It’s the king of the coral reefs. The humphead wrasse, fittingly named for the bump on its head, can grow to six feet long, weigh up to 400 pounds, and live for 30 years.

Also known as Napoleon wrasses, these giants are things of beauty, with diamond patterning, varying green, blue, and yellow scales, and distinctive “eyelashes”—black diagonal lines behind each eye. The fish live in tropical waters of nearly 50 countries, from the coast of East Africa to the Pacific Ocean.

But they’re disappearing because of their reputation for being delicious. They’re considered a luxury food in Hong Kong, where per capita fish consumption is among the highest in the world, according to the marine environmental nonprofit Bloom Hong Kong.

Fishing for humphead wrasses has intensified in recent years. In 2004, the International Union for Conservation of Nature (IUCN), which sets the conservation status of species, upgraded the fish from vulnerable to endangered. Also that year, the Convention on International Trade in Endangered Species of Fauna and Flora (CITES), the body that regulates cross-border commerce in wildlife, set more stringent regulations to protect the species from overexploitation. Many countries where humpheads are found have banned their trade, but Indonesia—whose waters encompass about a fifth of the humphead’s range—allows 2,000 to be exported each year, a number some experts worry is too high.
© NGP, Content may not reflect National Geographic’s current map policy.

Humphead wrasse can be found in the Coral Triangle, as well as on coral reefs throughout much of the Indian and Pacific Oceans.

Yvonne Sadovy, a professor at the University of Hong Kong’s Swire Institute of Marine Sciences and co-chair of the IUCN’s grouper and wrasse specialist group, says it’s unknown how many humpheads remain in the seas or what their rate of decline has been. What is well known is that the ecologically important Coral Triangle, encompassing a significant part of the humphead’s range, is threatened by overfishing.

Unlike elephants, humphead wrasses don’t get a lot of publicity, but they’re “in probably a worse state of trouble,” says Colman O’Criodain, the World Wildlife Fund’s policy manager for wildlife. Sadovy, who led recent humphead wrasse population surveys, says the fish were so scarce that “we were really quite shocked.” She also hears from divers and biologists that they no longer see mature humpheads in the wild.
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The fact that humpheads are scarce in the wild, despite protections, is evidence of illegal fishing and trading, but ascertaining the scale of the illegal trade is very difficult. Online trading platforms such as the Chinese ecommerce sites TMall and Taobao can facilitate illicit trade, Sadovy says. Social media, chat rooms, and WhatsApp groups, make it “much harder to detect,” O’Criodain says.

The lack of tracking for humpheads motivated Sadovy to create a tool that could be used by both authorities and the public. In what would be a first for fish, facial recognition technology uses the fish’s unique eye marks to determine if a humphead was imported legally. Working with a developer, she created Saving Face, a smartphone app that would enable diners, restaurateurs, and endangered species enforcement officers to compare a photo of a humphead wrasse for sale at a restaurant or market to photos in a database of legally imported humpheads.

The app is still in the testing phase, Sadovy says. She hopes Hong Kong will help promote the app and that it will empower people to be consumer watchdogs and help stop the selling of illegal fish. She says a growing number of restaurants in Hong Kong are intent on offering only legally sourced species that aren’t compromised in the wild, while consumers themselves are becoming more aware of beleaguered species they should avoid eating.

For the app to have a real impact on the illegal trade, Hong Kong would need to have enough inspectors at its ports to photograph each imported live wrasse to register in the app’s database. Further, there would need to be widespread adoption of the app by restaurateurs who buy the fish from wholesalers and restaurant diners. Then if the app does raise questions about the legality of a fish, app users would need to take it upon themselves to report the lack of facial matches to endangered species enforcement officers, who would need to prioritize following up on those reports.

The Hong Kong government needs to make more effort to educate and raise awareness among the public, the hospitality industry, and seafood traders, Sadovy says. “I think there’s a real need for education.”
From Indonesia to Hong Kong

Indonesia not only exports wild-caught humpheads but also ones raised in captivity, in the remote Anambas Islands and Natuna Islands. In 2018, for the first time, the country established an annual export quota of
40,000 for ranched humpheads. These are fish taken from the wild as juveniles and raised in pens. As with the wild fish, they’re shipped live, mostly to Hong Kong, to be kept in tanks in markets and restaurants until they’re sold for a meal (or die of other causes). This flood of humpheads into the market has made enforcement even more difficult, both because of the sheer number of fish and because there’s no way to distinguish between wild and ranched humpheads.

O’Criodain is worried that ranching may worsen the plight of these endangered fish. He says removing pre-reproductive-age wrasses from diminished wild populations may compromise their ability to rebound and that Indonesia doesn’t fulfill the CITES rule that trade in ranched humpheads is permissible only if it won’t undermine wild populations.
“There’s nothing about the overall size of the population and whether the take of these juveniles is sustainable in relation to that overall size,” he says. CITES also requires that a certain number of ranched fish be returned to the wild to bolster diminishing populations, but according to O’Criodain, Indonesia hasn’t declared its intent to do that.
Picture of a humphead wrasse swimming over coral reef

A facial recognition app is being developed that uses the humpheads’ eye markings to help distinguish between legally and illegally traded fish.
Photograph by David Doubilet, Nat Geo Image Collection

The Indonesian Ministry of Marine Affairs and Fisheries, which oversees the trade in humphead wrasses, did not respond to requests for comment.

Hong Kong’s Agriculture, Fisheries, and Conservation Department issues fish import permits, manages trade in CITES-listed species, and carries out shipment inspections. Every Hong Kong humphead wrasse retailer must have a possession license, and it’s prohibited for vendors to buy and sell the fish from each other. But if humpheads are smuggled in with shipments of other fish they resemble—groupers, for example—they’re not officially documented.

As detailed in a 2016 report Sadovy cowrote for Traffic, a nonprofit that tracks the wildlife trade, the number of humpheads offered in Hong Kong’s markets and restaurants exceeds the official, legal number.
Additionally, CITES records show that thousands of ranched Indonesian humphead wrasses are simply disappearing. In one instance, 8,000 ranched fish (with the proper CITES export permits) left Indonesia but never showed up anywhere else. “That disappearance means, because Hong Kong is quite good at reporting imports, that they’re going straight into mainland China and not being reported,” Sadovy says.

At present, the Hong Kong Customs and Excise Department is more intent on checking vessels suspected of carrying drugs or goods such as cigarettes, smuggled in to avoid customs duties, than illegal wildlife, says Sophie le Clue, environment director with the Hong Kong-based nonprofit ADM Capital Foundation. She says inspectors generally search for illegal wildlife only if they’ve been tipped off ahead of time; then they call in the Endangered Species division of the Agriculture, Fisheries, and Conservation Department for law enforcement action.

Officials from the department declined requests for an interview but sent an extended statement. Among other things, they said that “Hong Kong is committed to the protection of endangered species [and] takes vigorous enforcement actions together with the Customs and Excise Department in combating smuggling of Humphead wrasse to ensure that the trade in Humphead wrasse is in accordance with CITES and local legislation [and] conducts inspection on local market from time to time and appropriate enforcement action would be taken if any irregularity is spotted.”

The Endangered Species division itself doesn’t have an investigative body. Neither it nor Customs and Excise likely has enough staff or resources to inspect and track all shipments of live fish, says Stanley Shea, Bloom Hong Kong’s marine director.
’Saving Face’ for saving fish

Sadovy says the Saving Face app will be available at no cost. Here’s how authorities and the public will be able to use it: When legally imported fish with proper documentation arrive in Hong Kong, Endangered Species division personnel will photograph them and upload the photos to a database connected to the app. When enforcement officers or diners want to check the legality of a humphead, they can take a photo of the fish and, using the app, ascertain whether it matches one recorded in the database. If it doesn’t, they can use the Endangered Species division’s public reporting phone line to alert authorities.

According to Sadovy, a pilot project tested in the spring of 2019 showed that the app had a 70 percent match accuracy rate. She and the developer are now working on improving the accuracy rate, as well as enabling a desktop and cloud version that would make the system useful for high-volume import inspections. They plan to launch this in June.

Despite the limited number of Endangered Species division inspectors, Sadovy says the Agriculture, Fisheries, and Conservation Department has committed to using the app to process all labeled imports of live wild humphead wrasses. Ranched wrasses, however, make up the majority of imports, and it’s far from clear whether Hong Kong would have the staff to process those as well in the future.

Anil Jain, professor of computer science and engineering at Michigan State University, in East Lansing, whose biometrics lab developed a facial recognition system for primates, says the tool is promising but imperfect. Environmental factors such as cloudy water or bad lighting can affect image quality and compromise accuracy.

Eventually, with sufficient data, Sadovy envisions that the app could be used as a tool to combat trafficking of other wildlife besides humphead wrasses. “If there’s enough sample data,” she says, “enforcers could use this for all sorts of imports.”


Climate change: Oceans running out of oxygen as temperatures rise

  • 8 hours ago
Related Topics

sharkImage copyrightIUCN

Climate change and nutrient pollution are driving the oxygen from our oceans, and threatening many species of fish.

That’s the conclusion of the biggest study of its kind, undertaken by conservation group IUCN.

While nutrient run-off has been known for decades, researchers say that climate change is making the lack of oxygen worse.

Around 700 ocean sites are now suffering from low oxygen, compared with 45 in the 1960s.

Researchers say the depletion is threatening species including tuna, marlin and sharks.

The threat to oceans from nutrient run-off of chemicals such as nitrogen and phosphorus from farms and industry has long been known to impact the levels of oxygen in the sea waters and still remains the primary factor, especially closer to coasts.

However, in recent years the threat from climate change has increased.

As more carbon dioxide is released enhancing the greenhouse effect, much of the heat is absorbed by the oceans. In turn, this warmer water can hold less oxygen. The scientists estimate that between 1960 and 2010, the amount of the gas dissolved in the oceans de

Media captionClimate change: How 1.5C could change the world

That may not seem like much as it is a global average, but in some tropical locations the loss can range up to 40%.

Even small changes can impact marine life in a significant way. So waters with less oxygen favour species such as jellyfish, but not so good for bigger, fast-swimming species like tuna.

OxygenImage copyrightIUCN

“We have known about de-oxygenation but we haven’t known the linkages to climate change and this is really worrying,” said Minna Epps from IUCN.

“Not only has the decline of oxygen quadrupled in the past 50 years but even in the best case emissions scenario, oxygen is still going to decline in the oceans.”

For species like tuna, marlin and some sharks that are particularly sensitive to lack of oxygen – this is bad news.

Bigger fish like these have greater energy needs. According to the authors, these animals are starting to move to the shallow surface layers of the seas where there is more of the gas dissolved. However, this make the species much more vulnerable to over-fishing.

If countries continue with a business-as-usual approach to emissions, the world’s oceans are expected to lose 3-4% of their oxygen by the year 2100.

This is likely to be worse in the tropical regions of the world. Much of the loss is expected in the top 1,000m of the water column, which is richest in biodiversity.

TunaImage copyrightIUCN
Image captionTuna are suffering from lack of oxygen, says IUCN

Low levels of oxygen are also bad for basic processes like the cycling of elements crucial for life on Earth, including nitrogen and phosphorous.

“If we run out of oxygen it will mean habitat loss and biodiversity loss and a slippery slope down to slime and more jellyfish,” said Minna Epps.

“It will also change the energy and the biochemical cycling in the oceans and we don’t know what these biological and chemical shifts in the oceans can actually do.”

Changing the outcomes for the oceans is down to the world’s political leaders which is why the report has been launched here at COP25.

“Ocean oxygen depletion is menacing marine ecosystems already under stress from ocean warming and acidification,” said Dan Laffoley, also from IUCN and the report’s co-editor.

“To stop the worrying expansion of oxygen-poor areas, we need to decisively curb greenhouse gas emissions as well as nutrient pollution from agriculture and other sources.”