Seaspiracy fact check: A marine scientist debunks the controversial Netflix doc

Seaspiracy has been making waves ever since Netflix released it on March 24.

The documentary from British filmmaker Ali Tabrizi broke into Netflix’s coveted “Top 10” for trending shows and movies due to its dramatic and sometimes nauseating portrayal of the modern fishing industry. It could make you give up your weekly sushi order for good.

The backlash to Seaspiracy came just as fast as the praise. Many of the people interviewed for the film say their quotes were taken out of context, while other scientists called out the documentary’s many overstatements and flat-out errors.

One of those scientists was Bryce D. Stewart, who wrote on Twitter that Seaspiracy “regularly exaggerates & makes links where there aren't any.”

Stewart is a marine ecologist and fisheries biologist at the University of York in England. He has spent 20 years researching the managing of fisheries and marine protected areas. So we reached out to Stewart to find out exactly what Seaspiracy gets wrong.

“The biggest error is to say that sustainable fisheries don’t exist,” he tells Inverse via email. “This is like saying that sustainable agriculture doesn’t exist.”

In the interview below, Stewart goes into detail on how Seaspiracy gets this basic concept so wrong and some of the other errors the film makes, along with a few things it gets right and his recommendation for the ocean documentary you need to watch instead (or at least as a palate cleanser right afterward).

Inverse: Seaspiracy gets a lot of things wrong, but what is the most egregious error in the documentary?

Dr. Bryce D. Stewart: The biggest error is to say that sustainable fisheries don’t exist. This is like saying that sustainable agriculture doesn’t exist. All food production systems have an impact on the natural world, but obviously some more than others. However, sustainable fisheries do indeed exist; in the most recent assessment by the United Nations Food and Agriculture Organisation it was calculated that almost two-thirds of fish stocks were being harvested sustainably (65.8 percent) and that 78.7 percent of all landings of marine fisheries come from biologically sustainable stocks. However, this doesn’t mean there are not problems; approximately 34 percent of fish stocks are now overfished and this proportion has increased from only 10 percent in 1990.

What's something important that the movie gets right?

The movie was right to highlight overfishing as the biggest current threat to marine biodiversity. This is widely accepted by scientists and the evidence for this is very strong. Overfishing is often driven by greed and the desire to maximize profits, but it is also driven by inequality, poverty, and poor management which leaves people with few other options. Overfishing also interacts with the many other threats to the ocean such as climate change, ocean acidification, and pollution. All of these threats need to be tackled simultaneously, it is ineffective to treat them in isolation.

“The movie was right to highlight overfishing as the biggest current threat to marine biodiversity.”

What's one lesson we should learn from Seaspiracy?

The ocean is indeed crucial to humanity. The movie didn’t get all of these facts right, but the ocean absorbs over 90 percent of the heat that enters the atmosphere, it provides over half of the oxygen we breathe, it supplies over 3 billion people with 20 percent of their daily protein needs, it enables global trade and transport, and it provides health and wellbeing benefits to millions, if not billions of people. Without the ocean, humans could not exist on Earth.

What's one thing you would change about the movie?

I can’t pick just one, but I will keep it to two. Firstly, it needed to be much more scientifically accurate. Many of the statements made were based on outdated studies, while other issues were grossly exaggerated and links were often made where they don’t exist. These errors make it very easy for decision-makers (e.g. governments) to ignore the messages in the film and for unsustainable fishers to dismiss the film entirely.

The second thing I would change is to bring in a diversity of views. Almost all of the interviewees were white and from the western world. We needed to hear from a range of ethnicities and cultures, we needed to hear from the seafood industry, from managers, and from NGOs in a non-selective way. Almost no fisheries scientists were interviewed for the film, which is a major omission in a film about overfishing.

If we want to save the ocean, do we need to stop eating fish?

If people want to stop eating fish, for whatever reason, that is fine, it’s a personal choice. But it is simply not necessary or an option for millions, if not billions, of people. As mentioned previously, over 3 billion people get 20 percent of their protein from aquatic food. Plus over 60 million people are directly employed in fisheries and aquaculture.

In many island nations and coastal areas, there are few if any other options for obtaining the nutrition that fish provides. Fish and fishing are also an integral part of the cultures of many places and nations. This is not just the case in the Global South; take Iceland for example where fishing-related activities provide approximately 25 percent of their GDP, or even the UK, where fish and chips are considered the national dish.

“Well-managed fisheries and aquaculture systems actually have a much lower impact than many other food production systems.”

Overfishing is indeed a problem, but we know sustainable fisheries are possible. If we turned entirely to the land for the nutrition that the world currently gains from the sea, the environmental impacts on land would be catastrophic and much more visible to humans. In terms of carbon footprint, well-managed fisheries and aquaculture systems actually have a much lower impact than many other food production systems.

Are farmed fish a solution to that problem?

Aquaculture currently provides about half of all of the fish or seafood in the world and its further expansion is necessary if we are to feed the growing global population. Even with improved fisheries management, we are unlikely to be able to sustainably produce much more seafood from wild capture fisheries.

However, there are certainly significant issues with the farming of species like salmon and prawns. The industry is starting to tackle these but is not moving fast enough and a lot of damage needs to be undone e.g. restoration of mangroves destroyed by prawn farms. But it is important to note that these are only some of the species produced by aquaculture. Farming of herbivorous species has a very low environmental impact, and farming shellfish such as oysters, mussels, and scallops has almost no impact.

These shellfish farms provide habitat for other species, they filter seawater and they absorb carbon. Multi-trophic aquaculture, where species like fish, shellfish, and seaweeds are farmed together, can make aquaculture much more sustainable. Likewise, moving salmon and prawn farming into closed circulation systems on land would also reduce many environmental impacts.

What's a documentary on this topic that you actually would recommend to people who want to learn more?

I think a new documentary needs to be made in response to this Seaspiracy! The 2009 film End of the Line is much more informative and meticulously put together, although that was 12 years ago now. Another much more scientifically accurate and balanced film is Troubled Waters available on YouTube. This was made as a student project by a former student of mine, Matthew Judge, on almost no budget. But it neatly highlights both the issues and the good news stories and demonstrates how individual actions can make a difference.