Several weeks ago I watched Seaspiracy on Netflix. The documentary manages to engage its viewers well, shocking them with its portrayal of fishing industry. But by the end of the documentary, which concludes that eating fish is unsustainable and advises us to stop doing so, I was already having doubts. What about the mussels we produce in The Netherlands for example? I know mussels are molluscs and not fish, but the documentary also covered shrimp, which are crustaceans. I just want to take care to avoid the word seafood, because that would also include seaweed, which is not under discussion here.
It turns out that mussels feed on plankton already present in seawater, so their production requires no feed and is very sustainable. I went on to read several responses to the film, such as those on the Wageningen University blog, the Sustainable Fisheries website of the University of Washington, Otter Strategies and one published on Inverse. I suggest you read those for yourself because it’s a lot of information to summarize here, but I’ll highlight some of the most important criticisms here.
It turns out that the seas won’t be empty by 2048 and many fisheries are sustainable. The Marine Stewardship Council (MSC) uses third-party assessors to certify fisheries rather than doing so itself. I still think it’s unfortunate that the MSC didn’t have an interview with the makers of the documentary though. Seaspiracy criticizes aquaculture for it’s use of fish meal as feed for the farmed fish. It turns out that the proportion of fish meal in the diet of farmed fish has already been strongly reduced over the years. Also, it can and likely will be replaced entirely by other more sustainable feed sources, such as insects. In some places in Southeast Asia, freshwater fish are already farmed sustainably without fish meal.
Perhaps the most unnerving image of the whole documentary was a salmon slowly being flayed and eaten alive by sea lice. It appears sea lice are indeed a problem, but they also affect wild salmon. Since a sea lice infection makes salmon unmarketable, fish farmers have a clear incentive to prevent that from happening. I felt Seaspiracy was weak at this point, because all it did was shock the viewer. There was no discussion on statistics or scientific studies on sea lice infections at all.
While the responses to Seaspiracy often point out errors in the ratio of discarded plastic fishing nets and plastic straws claimed in the documentary, they seem to ignore the core of the problem. Why is plastic being used in fishing nets in the first place, I wonder? Fishing nets have been made for thousands of years before the invention of plastic. Since it’s impossible for law enforcement to monitor the deliberate discarding or accidental loss of those fishing nets far out at sea, it seems easier to to make legislation for the production of fishing nets. I hope legislation will be made banning the use of any material which is not biodegradable in fishing nets, such as plastics.
Elsewhere on the Sustainable Fisheries website, there is an interesting comparison based on scientific literature which compares greenhouse gas emissions for several different foods. Beef and aquaculture catfish turn out to be the worst offenders, but the Impossible Burger 2.0 and aquaculture salmon create far less emissions. The winners in terms of emissions however, are captured small pelagic fish, captured whitefish and aquaculture mollusks. They also point out that fish are more nutritious than the Impossible Burger, which contains a large amount of saturated fat.
Small pelagic fish are apparently fish such as anchovies, sardines, mackerel and herring, exactly the kind of fish I like to eat. I also use tuna (with MSC certification), primarily on pizza. I only eat a small amount of fish once or twice a week and considering that these fish species can or could be caught or farmed sustainably, I see no reason to change my behavior.
I do think we should all consult the guides on which fish is sustainable, such as the VISwijzer for those in the Netherlands (also available in English). For example, what surprises me is that the capture critically endangered species like the European eel is still allowed. I know governments have taken some preservation for the eel already, but it looks like they’re not doing enough. This shows that not only our government has a responsibility, but that consumers should also educate themselves on what kind of fish they are buying as long as the government doesn’t get this right.