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The website did have a "FACTS" link on its top banner which lead to a page saying that the facts page would be coming "this week". This link has now disappeared; thus there seems no indication of the film's sources.

Commentaries on the film

WishfulZoomer Reddit

There's a lot to unpack in the documentary that's for sure. Becoming a vegan is an option that is available. Eating fish is also something they people can still enjoy. This is a multifaceted issue. I may miss a few of the points here but this is what has been outlined in the film:

The killing of intelligent animals

The exploitation of workers

The polluting of our oceans

The, for lack of a better term at the moment, Deforestation of the ocean floor

Lack of government oversight

I've been reading the reviews of Seaspiracy and reviewers seem not to like the director, Ali Tabrizi. For the sake of arguement I would like to view the content of the documentary aside from the directors personal feelings. He and his wife are shooting firsthand. They are on the scene of these fishing operations. The killing of dolphins in Taiji or pilot whales in the faroe islands is a difficult thing to watch. They see a bluefin tuna operation. A man cutting the fins off of sharks. What most of the reviewers are missing is the blatant destruction of life. It is right in your face and there's really no way to explain out of the images being seen.

A quick google search reveals that the sea slavery is very much an ongoing problem.

Many of the slaves being taken onto these vessels are coming from Cambodia and Myanmar. So with the current instability in the region we should be watching to see if there is an influx in human trafficking through Thailand in the coming months.

The human equity problem is real. It's another issue that people are choosing to ignore. It is a far away issue that has consequences in your town, on your supermarket shelves. I believe people are misinformed not wholly ignorant.

The Seaspiracy website does not have its fact page up yet but im pretty sure I have tracked down one of the sources attributing to the claim 94% of ocean plastic is fishing related. Through a National geographic article published on March 22, 2018, they cite from the The Ocean Clean Up. The company published a research paper titled "The Exponential Increase of the Great Pacific Garbage Patch".

They concluded 94% of the individual pieces of plastic found in the GPGP were microplastics. Another damning statistic is they have found that 46% of the total mass was fishing gear. They previously thought before conducting research that fishing gear would account for around 20% of total mass. That is a very wide divide. As a world we must accelerate the phase out of plastics over all. The problem is vast. Plastic is involved in every business, every single car on the road, every household. The corporations try to pass these burdens and problems on to us the consumer. We collectively can take action to force change in all industries not just fishing.

There's research going on every day looking at the impact of trawling on marine life as well as the carbon intake of the ocean. This issue is especially messy. The destruction of coral reefs and sea plants, the unnecessary killing of bycatch, and the dredging up of the top soil into the upper levels of water. Through reading some research there was not a clear cut consensus.

I feel like the reason behind this is a hesitancy to go against the establishment. We know that we are destroying delicate ecosystems. That should be evidence enough. Silent Spring showed us the impact of encroaching haphazardly into ecosystems without first understanding what our impact would be.

These are a few things I read on trawling and the impact, the dates vary but theres useful information that can bring some better understanding to how complex of an issue we are dealing with.

I also did some reading on Marine Protected Areas. This is an umbrella term used by the government to designate activities within a nautical area. The National Oceanic and Atmospheric Administration is where I found data on MPAs. NOAA states the United States has established over 1000 MPAs. There is a term called a "no-take" region. This would be an area where no fishing or extractive practices can occur. The data is confusing and I will link the page that I found it on.

It is either 3% or 8% of United States MPAs are no-take zones. That honestly feels laughable. The information is on the second page it feels intentionally misleading. This will all be different country to country. Some may be doing a better job others worse.

It really does come down to just informing people. The documentary absolutely wants people to, at the very least, cut their consumption of fish down. I do not see this as a vegan issue, I do not see this as an attack on people who eat fish, meat, poultry or any other animal. I really see it as corporations greed spilling over into every facet of our lives. Countries politicians alway talk of not having outside countries jumping into their internal affairs. We are in a world economy now. We have been since the 1980s. Everything is so interconnected that the issue of a teenager in America very well may align with a teenager in China, Somolia, Thailand, or Spain. We should all be joining together to take on the companies that engage in extractive practices that take advantage of indigenous people across the globe.

Your local fisherman with his couple of crab pots and a couple of rods is not the problem here. It's big business, government sponsored encroachment into protected waters, unsustainable and non regenerative havoc wreaking practices.

Everyone saw the power held by traders of gamestop stock. Focus that energy on driving your cars less, on picking items that do not contain plastic waste. Support local farmers, see if there is a butcher or fisherman near you that can guarantee the animals they raise or catch are indeed raised and have their life ended with some decency. It is uncomfortable to change our lives drastically, but there is in fact only one Earth that we have. We have saved ourselves from the brink in the past, we can absolutely do it again.

Stay positive in light of the horrible things going on in this world because we can change things. We can make a better future for our children. We can protect the other lives that share this Earth with us. Each and every one of us can make a difference. Talk to your friends, your family, your communities. A societal tipping point can be reached and it's up to us to reach it.

View discussions in 10 other communities

Jean Utzurrum @jean8rum on Twitter

Because a lot of my non-scientific friends asked me to share my thoughts on Seaspiracy, I wrote a lengthy note about it shared on Facebook and set to public. Facebook post

OK, so I finally watched Seaspiracy on Netflix and it wasn't entirely terrible if you disregard all the factual inaccuracies, manipulation of interviews, overtones of anti-Asian racism, and grossly false retelling of Gerlie Alpajora's death (

The film raises valid issues about marine and coastal ecosystems, which can be a lot to take in all at once. Squeezing all these issues into a 90-minute film just didn't do any of these issues justice. So I'm going to try and break them down here. If you don't care about my detailed thoughts on this, feel free to skip to the end or ignore this [very lengthy] post entirely.

‼️ SPOILER ALERT ‼️ Story Time!

The film maker Ali Tabrizi goes down a rabbit hole discovering these issues for the first time in his self-absorbed life, asking "How come I didn't know this?". Most of us have been down this hole and understand such existential awakening is normal but can be overwhelming; Tabrizi's storytelling leans heavily on the latter. He falls deep into the hole and ends up obsessing over the broad issue of fisheries whilst skirting around relevant issues, bouncing from one problem (and country) to another, without ever discovering any viable solutions to those issues. To add to his frustration, he discovers that his favourite charities are all frauds contributing to all these problems and is intent to find out why. So he tries to interview a bunch of people; some of them cooperate, others don't. He tries to investigate covertly but - argh! - more problems, which further convinces him there's a global conspiracy among scientists, conservation charities, governments, and fishing operators. He eventually ends his journey in a sombre, reflective mood and concludes the best thing he can do for ocean conservation is to not eat fish.

"Film critic ka Gh0rL?"

Nope, but I'm going to share my thoughts anyway. IMHO, not taking into account the 4 major issues that make this film problematic (see v. top of post), this film is a bad rehash of other documentaries. From a journalism perspective, Tabrizi's theme of discovering different ocean issues for the very first time reveals he's a shoddy investigative filmmaker.

  • Taiji dolphin hunt? Watch The Cove.
  • Shark fishing and shark finning? Watch the Sharkwater films. [side note: the two do not mean the same thing and Tabrizi fails to make this distinction]
  • Dolphins in captivity? Blackfish.
  • Ocean plastic pollution? A Plastic Ocean.
  • Coral reefs dying? Chasing Coral.
  • Industrial fisheries? End of the Line.
  • Faroe Islands grind? Literally, a spinoff series of Whale Wars.

Also, for a self-proclaimed ocean lover who uses the internet a lot to "discover" these issues for the very first time in his life, I can't quite see how he could not have known about these issues. And while the films and series I mentioned above certainly had their own share of criticisms, I still think you'd learn a lot more about these individual issues from these documentaries than from some noob who researched his homework on Wikipedia.

"At least it raises awareness"' not necessarily helpful to conservation if a few truths are thrown into a sea of oversimplified interpretations - and worse, misinformation - on a broad topic that encompasses a series of complex, intersectional issues. I know the film wasn't intended for scientists but would non-scientific folks be able to differentiate between facts and falsehoods? 🤔 Would those not working in conservation be able to pick up on socio-economic context and cultural nuance of the issues presented?

Fisheries is a complex issue at any level - municipal, national, regional, transnational, and high seas. Moreover, science intersects with economics, governance, politics, anthropology, and social justice at each of these levels. And my goodness,😳 the science itself is multifaceted! There are different magnitudes of fishing (e.g. industrial, commercial, small-scale, artisanal) and types of fisheries (e.g. tuna, shrimp, salmon) that use a variety of gears (e.g. trawls, longlines, gillnets, pots). Tabrizi fails to make these distinctions, which is unsurprising, given his superficial investigative skills. Instead, he loosely refers to fishing and fisheries interchangeably and, without providing context and nuance, constantly points to this as the biggest threat our oceans are facing right now [📢NEWS FLASH: it's not 🙅🏽‍♀️ Global warming 🌏🌡 is still a much bigger threat]. The audience is then left to draw conclusions from a magician's hat or accept Tabrizi's film as fact.

"But Sylvia Earle was in it so it must be factual"

Scientists appearing in documentaries or interviews does not necessarily mean the piece is correct. While I have no doubt that Dr. Sylvia Earle's segment was as authentic as it could be, Dr. Christina Hicks has publicly said that she does not endorse the film's message ( and that she was not informed what the film was about at the time of the interview (, or that it was for a film. In my personal experiences and observations of other scientists engaging media, a 30-minute interview can easily be taken out of context by a 3-minute sound byte cherry picked to fit a narrative that's already been written by media executives. As scientists, we don't mind talking about our research especially when most have poured long hours and/or dedicated their lives to their work *BUT* manipulative journalism by the likes of Tabrizi builds a wall of distrust between scientists and media professionals. What really 👎🏽 sunk 👎🏽 Tabrizi's film when it came to ethical journalism and credibility were the blatant lies used to reimagine Gerlie Alpajora's work and consequent death. Contrary to the film's depiction, Gerlie Alpajora was an officer of the Sagnay Tuna Fishing Association and was instrumental in combatting illegal fishing in Lagonoy Gulf; authorities believed her murder was connected to her campaigns against illegal fishers (

"So can I still eat fish?"

Op kors! While it's true there's no absolute definition of "sustainable", fisheries generally can be managed to a level where environmental impacts are much lower than without management interventions. This can be through a number of management tools but in the Philippines, the most popular tool is Marine Protected Areas (unfortunately, another issue that Tabrizi glossed over). The success of MPAs in conservation depends on several factors such as MPA design (i.e. area of coverage, site suitability), purpose (i.e. species/habitat conservation, mixed use resource, tourism), and governance (i.e. enforcement, institutional support). The one time MPAs are discussed in the film is in reference to mixed use resource, wherein a part of the MPA can be designated for different uses like fishing. In the Philippines, fishing is allowed in most MPAs in recognition of the fact that coastal communities rely on fishing activities for subsistence. Take for instance, Apo Island Protected Landscape and Seascape: in it's entirety it is a protected area but people are allowed to live on the island and fish outside of designated no-take marine reserves.

Will not eating fish help oceans? Yes, to an extent. Will not eating fish stop fisheries? No, not without management interventions and institutionalised support from governmental and independent bodies, and certainly not in countries where fisheries support coastal communities.

"But no one's asking [poor] people to give up their food and livelihood"

I hate to break it to you folks but the Philippines exports fisheries products globally so when the film ends with three Westerners telling viewers to not eat fish, the film does exactly this, albeit unintentionally perhaps. Fisheries in the Philippines are far from perfect but a lot of work and progress has been made to ensure some measures of sustainability. Indeed, the Philippine Fisheries Code was amended in 2014 to address Illegal, Unreported, and Unregulated (IUU) fishing after the EU scored our tuna fisheries with a red card. Similarly, the Visayan Sea blue swimming crab fisheries was rated by Seafood Watch as red (avoid); a collaborative project led by University of the Philippines Visayas is currently undertaken to improve this fishery through various activities, including a workshop on bycatch risk assessment that I had the pleasure of joining earlier this week. If you're worried about slave labor in fisheries, I know that there are some human rights groups looking into these. There's still a lot of work to be done but the constant vilification of scientists, conservation groups, and fishers portrayed in this film does not help progress overall marine conservation. In fact, while the film damns Oceana as having corrupt ties to fishing industries, Oceana Philippines has been leading a strong campaign against a proposed bill that will allow commercial fishing into municipal waters (

I have a lot more to say on fisheries, MPAs, and fishes but to conclude this segment, my hot tip would be to learn more about what food choices are locally available to you, and how they were caught or harvested. If worth anything, Seaspiracy should inspire you to be more intentional about your food choices. 💚

Last thoughts

I really hadn't intended to critically watch this film and write a long-ass commentary but I've had multiple non-scientific friends message to ask me for my thoughts on this precisely because they didn't want to play Two Truths and A Lie on their own, so here we are. Notice that I deliberately steered away from discussing the film's factual inaccuracies that many scientists have already pointed out, including the claim that we will have empty oceans by 2048 which the authors of that paper retracted in 2009 ( [broken link]). So many other marine scientists have shared their thoughts on this; there are too many to link in here but this one from Dr. James Bell is a good place to start ( [broken link]). I also am too tired by now to even attempt to explain to you all how problematic the overtones of racism in this film are, constantly reinforced by this narrative of a Westerner discovering things for the first time. 🙄 The bottom line is that marine conservation issues are complex, multifaceted, and intersectional. Tabrizi's film oversimplifies all these issues to justify his choice to simply not eat seafood.

Hope Spots

There's so much more that can be done for the oceans and there are so many engaging scientists on digital platforms that can help you understand how you can help; a personal fave of mine is the Speak Up For Blue podcast ([]). After the tough year we've all been having we really could've have used more good ocean news instead of a 90-minute mood fest. And there's a lot of good news out there 💙 like a new paper my colleagues and I published last week on the first sightings of 🐋 blue whales in the Philippines since the 19th century (! Shameless plug to end this but you're welcome 😂

I still have a lot of words about this film that I may need to get out of my system so I can start the week fresh.

Lemme just be clear --

I explicitly said those were *my* thoughts. If you didn't pick up on things I observed, that's fine. But I shouldn't have to explain why you didn't notice them, especially if you're not a POC.

Seaspiracy fact check: What Netflix documentary is about, and why its accuracy has faced questions Joanna Whitehead; i; 1 April 2021

Further reading & related

Dead Loss report

Dead Loss: the high cost of poor salmon farming practices Just Economics
Report | local copy (pdf)

This economic analysis of salmon farming reveals that the industry has produced negative externalities worth in the region of USD$47 billion since 2013. It shows how poor fish husbandry, including measures such as high stocking densities, are a false economy as they have led to increasing mortalities on salmon farms. These represent high opportunity costs for salmon farmers. In addition, unsustainable practices such as the use of fish in feed, local pollution and poor fish welfare create social and environmental costs that are not generally accounted for.

Salmon aquaculture is dominated by a small number of multinational producers operating in just four farming regions – Chile, Norway, Canada, and Scotland. Not only is it already the fastest growing food production sector in the world, but a continued global growth in demand is expected. However, it also generates considerable controversy, which has seen demand growth slow in developed countries, not least due to negative consumer perceptions of farmed salmon. Although promoted as a healthy and sustainable product, behind the marketing discourse, we find that transparency and accountability are extremely weak by comparison with land-based farming. Data are often absent on important phenomena such as mortalities, escapes and environmental impacts.

A combination of growing environmental impacts, consumer demand for ethical and environmentally-friendly products and direct losses from poor fish husbandry are creating long run economic risks to the industry, that can only be mitigated by investing in better farming practices and reduction of environmentally harmful aspects, such as use of wild-caught fish. Our recommendations focus on the four most significant stakeholders in salmon farming: governments, investors, farmers and consumers, each of which has a role to play in transitioning to a more sustainable aquaculture and food system.

Global salmon farming harming marine life and costing billions in damage Fiona Harvey; The Guardian; 11 Feb 2021

Report says pollution, parasites and fish mortality rates cost an estimated $50bn globally from 2013 to 2019 Salmon farming is wreaking ruin on marine ecosystems, through pollution, parasites and high fish mortality rates which are causing billions of pounds a year in damage, a new assessment of the global salmon farming industry has found.

Taken together, these costs amounted to about $50bn globally from 2013 to 2019, according to a report published on Thursday.

Fish mortality has more than quadrupled, from 3% in 2002 to about 13.5% in 2019, in Scottish salmon farms alone. About a fifth of these deaths are recorded as being due to sea lice infestations, but about two thirds are unaccounted for so the real mortality owing to sea lice – which feed on salmon skin and mucus, effectively eating the fish alive – could be much higher.

Scotland is one of the biggest producers of farmed salmon in the world, with the industry worth an estimated £2bn a year to the Scottish economy. But the costs in environmental terms alone were reckoned to be £1.4bn from 2013 to 2019, by Just Economics, which carried out the research for the report, entitled Dead Loss, for the Changing Markets Foundation campaigning organisation.

The sheer quantity of wild fish used in salmon farms is also a growing concern. About a fifth of the world’s annual wild fish catch, amounting to about 18m tonnes of wild fish a year, is used to make fishmeal and fish oil, of which about 70% goes to fish farms. This is causing problems for fishers in developing countries, who are seeing their stocks depleted in order to feed western consumption of farmed fish, according to the report.

Key species such as sardines in west Africa are now heavily overfished for this purpose, and this situation is likely to deteriorate further as fish farmers plan substantial expansion in the coming years. Scotland alone plans to double its farming capacity by 2030, while Norway expects a fivefold increase by 2050, according to the report.

Salmon farmers could use oils from algae as a source of Omega 3 for their farmed fish, to replace fish oil from wild fish, but few do so, according to the report. Natasha Hurley, campaigns manager at the Changing Markets Foundation, told the Guardian: “Moving away from using wild caught fish in food would make salmon farming more sustainable, as it is having a huge impact on wild fish.”

Report claims salmon farming costing economies, society, and the environment billions Jason Holland; Sea Food Source; 17 Feb 2021

The short-term pursuit of profits by salmon producers is creating significant unaccounted environmental and social costs – such as growing mortality rates, damage to local ecosystems, pressure on wild fish stocks, and poor fish welfare – a new report from research organization Just Economics claims.

Commissioned by the Changing Markets Foundation – an organization that “supports NGOs to drive change” – as part of its Fishing the Feed campaign, the “Dead Loss” report calculates the cumulative costs to economies, society, and the environment resulting from the negative impacts of salmon farming at almost USD 50 billion (EUR 41.2 billion) since 2013.

In the top four salmon-producing countries of Norway, Scotland, Canada, and Chile, which collectively account for 96 percent of the world’s 2.6 million metric tons (MT) of farmed salmon, more than half these costs are falling to producers (USD 28 billion, EUR 23.1 billion), with the remaining USD 19 billion (EUR 15.7 billion) being passed on to society.

Fish oil alternatives

[ Microbial and genetically engineered oils as replacements for fish oil in aquaculture feeds M. Sprague, M. B. Betancor, D. R. Tocher; Biotechnology Letters; July 2017


As the global population grows more of our fish and seafood are being farmed. Fish are the main dietary source of the omega-3 (n-3) long-chain polyunsaturated fatty acids (LC-PUFA), eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids, but these cannot be produced in sufficient quantities as are now required for human health. Farmed fish have traditionally been fed a diet consisting of fishmeal and fish oil, rich in n-3 LC-PUFA. However, the increase in global aquaculture production has resulted in these finite and limited marine ingredients being replaced with sustainable alternatives of terrestrial origin that are devoid of n-3 LC-PUFA. Consequently, the nutritional value of the final product has been partially compromised with EPA and DHA levels both falling. Recent calls from the salmon industry for new sources of n-3 LC-PUFA have received significant commercial interest. Thus, this review explores the technologies being applied to produce de novo n-3 LC-PUFA sources, namely microalgae and genetically engineered oilseed crops, and how they may be used in aquafeeds to ensure that farmed fish remain a healthy component of the human diet.


One criticism that has been made of the film is that it displays racist attitudes to those in the developing world shown in the film. An article "Seaspiracy- Why as an Asian ocean activist it was so harmful" by Kaelyn Maehara in Medium (around 6th April 2021) articulates why:

I love the oceans. I’ve built my entire life around ocean advocacy and working to protect marine life. I’ve even spent time crewing for Sea Shepherd campaigns in Antarctica and Mexico fighting against illegal fishing and have worked on nature documentaries trying to show the oceans’ wonders to the world. I also don’t eat meat or fish and I do not encourage many people to do so. So when Seaspiracy came out on Netflix, I was excited to see a film aimed at tackling the oceans problems, one that included hard-hitting facts about overfishing and reached a wide audience with its strong environmental messaging. I was excited to watch it but as I watched I found myself more upset than anything else. I was appalled at the ignorance, the racist portrayal (and complete absence) of communities of color, the white savior narrative, and the oversimplification of an immense and complex issue that just hands the burden onto consumers.

First of all, I’d like to say that I support the message that privileged people from rich nations who get their food at grocery stores should think twice about buying seafood because indeed industrial fishing is linked to a whole host of environmental and social issues. I agree with that statement. However, while this message applies to some, it does not apply to everyone around the globe equally. It is not so simple. The solutions to fixing our seas are more complicated and nuanced. We must consider the economic, environmental, and social factors which mean giving up fish is not a viable solution for everyone. We must remember, not all people have the same exploitative relationship with the oceans. Millions of small-scale indigenous fishers are an integral part of their ecosystems and have been natural custodians for the oceans for millennia and they too are struggling under the weight of industrial fishing. We cannot make blanket statements that all people must stop eating fish without understanding the reality of that statement and the vulnerable communities it affects the most. For a wealthy and privileged audience, the films’ message resonates, but the way in which that point is made, could not have been more harmful.

The film centers itself around a very limited middle-class western perspective which is something we see in conservation time and time again. Frankly, I am tired of listening to mostly white middle-class people touting solutions to save the oceans that do not include or consider colonial/imperialist history, geopolitical, or cultural context and portray people of color according to stereotypes and without allowing them a voice. There were very few non-white people in this film and of the few groups that were, they were portrayed as the evil ocean plunderers or the helpless victims- neither were given any control over their own stories and the rest of the non-western world seemed to not exist at all. This blatant use of racism and erasure in service of a white-centered narrative and the use of stereotypes and othering to “make a point” is something we can no longer tolerate.

As an Asian woman, I found the portrayal of Asians in this film as a homogenous group of ocean villains deeply upsetting and downright irresponsible at a time when anti-Asian hate is skyrocketing worldwide and we know that negative Asian stereotypes are what’s behind these attacks. This narrative not only does great harm to our communities, but cumulative insensitive rhetoric emboldens people to attack us in the streets in the name of the environment.

I have personally been a victim of this. I was berated by someone who hated Japanese whalers and looked at me and saw the enemy. Never mind I have nothing to do with whaling, or that I was actually part of an anti-whaling campaign to Antarctica to save whales from slaughter- none of that mattered. This individual felt it was okay to say horribly racist things to me because they did not see me as an ocean activist or even as a human being- instead all they saw was an evil Asian stereotype who should be blamed for killing the oceans.

This film, seen by millions, will further strengthen those dangerous stereotypes and will leave an entire community vulnerable and left without a voice at the worst time possible. Demonizing Asians is not the only way to tell this story. Factually, Norway kills more whales than any other country in the world, more than Japan and Iceland combined. But the Norwegian whaler stereotype (or lack thereof) just doesn’t evoke that same visceral and emotional response (alarm bells ringing) filmmakers need to sell a story. Ergo, the role of the villain is placed on the “foreign-looking” Japanese.

read more


Net loss: the high price of salmon farming Mark Kurlansky; The Guardian; 15 Sep 2020

The salmon has always been a barometer for the health of the planet. Now industrial-scale farming is bringing pollution, plagues of sea lice and threatening the future of wild salmon

There is a growing realisation, greatly promoted by the United Nations Food and Agriculture Organization (FAO), that we have to start producing much more protein to sustain a growing world population. The FAO believes that we cannot afford to plough up more land for agriculture and we need to derive more protein from the sea. This is clearly not going to be accomplished with wild fish, already struggling under the effects of climate change. One way to make the sea productive is fish farming. But fish farming currently creates as many problems as it solves.

Atourist viewing the dramatic sheer mountain fjords of Norway and the island-strewn mouths of the rivers or passing the lochs of Scotland might easily never notice the presence of fish farms. They might see an unobtrusive area with metal poles sticking about a metre out of the water and perhaps some netting over the top of floating wooden walkways; it doesn’t look like much. Invisible from across the loch are a million salmon below. A visitor looking closely might see a few salmon leaping, because salmon always leap.

But passersby see very little because most of the farm – other than a few tubes to a feeder, the top rim of a fish pen that goes down some 50 metres (164ft), and usually a barge – is below the surface of the water. The pen needs to be placed in deep water because it cannot rest on the bottom and should have more than 30 metres of swiftly moving ocean current rushing under it. The pen is large enough for about 200,000 fish – as some opponents point out, packed in tightly. But fish generally don’t mind a crowd, believing there is safety in numbers. Even in these packed pens, there is open water as well as crowded areas.

In Norway, where fish farming is big business, a farm might have eight or 10 pens, which would hold more fish than the wild Atlantic salmon population of the entire world. Originally fish farms in Norway were not this large. Salmon farming started in Norway in the 70s as an extension of normal agriculture, and a farmer would get a licence for one pen that would be placed in the sea as close as possible to the farm. But farmers discovered that fish farming required a great deal of capital and most gave up. At the same time, they found that if you had the capital and could farm on a large scale, it was enormously profitable. So large companies started buying up licences from failing farms, meaning it was soon a large-scale industry. A few one-licence farms still exist, but most salmon farming operations are owned by large multinational companies.

The first complaint against salmon farming is that it is polluting. A pen with 200,000 fish produces an enormous amount of waste. In nature, animal waste is not harmful; in fact it is often beneficial. But large concentrations of it can be destructive. The waste of wild fish swimming around is not harmful, but the waste of hundreds of thousands staying in the same spot is.