Once upon a time, all of the wisdom of the world was held in the body of one fish, the Salmon of Knowledge. It was an ordinary salmon that happened to eat nine hazelnuts that fell from nine hazel trees surrounding the Well of Wisdom. It was said that whoever ate this salmon would be unfailingly wise.
Irish legend has it that the giant Fionn Mac Cumhaill (Finn McCool) cooked that salmon, and burned his thumb on its skin. When he sucked his thumb, he became wise, and when he ate the salmon, he knew everything.
I don’t know why the salmon was thought to be so wise. I hope that it comes from the evolutionary genius that has enabled salmon to return to the rivers they were born to spawn, a place they haven’t been since they were born, navigating by their sense of smell, the earth’s magnetic field, and the pull of their own genetic inheritance.
Maybe this legend, like folklore around the world, was passed down because it transmitted essential ideas about group culture and survival. To eat salmon is essential, but these fish are also valuable, beyond their worth to people.
This story exists, in some form or another, in mythology from the British Isles and Scandinavia, where salmon were once plentiful and also a luxury.
In the ensuing centuries, it has become clear that either Fionn Mac Cumhaill stopped sucking his thumb or, unlike him, we have become unable to hold onto their wisdom. In the effort to transform salmon into money by domesticating and farming it, the aquaculture industry (and all of us who eat salmon), seem to have lost track of what makes the salmon actually valuable.
Why am I writing about this? Because I recently reviewed a book about the Norwegian and global farmed salmon industry, The New Fish: The Truth About Farmed Salmon and the Consequences We Can No Longer Ignore, by Simen Saetre and Kjetil Østli, trans. from the Norwegian by Sian Mackie, for the New York Times.
But I begin with this (admittedly kooky) detour into ancient Irish mythology because the book, and the lessons it offers, read almost like a parable about man’s hubris and the limits of innovation and intervention in the natural world. It prompted me to think again about the important question of what kinds of tradeoffs we are willing to accept.
I thought I knew at least something — or at least not nothing — about aquaculture in general and salmon farming in particular from research I did for my book: farmed fish are eating lots of corn and soy, some of which is grown in the Amazon, contributing to deforestation there; and they are also eating foraged fish (like anchovy and other small fin fish), made into meal and oil, contributing in some places, to overfishing of those fisheries. I knew antibiotics were a concern.
But the information in this book was really shocking to me, and I kind of can’t believe that I didn’t know or hadn’t thought more carefully about this: that in just a few decades, humanity has domesticated a wild animal, and turned it into the fastest-growing food production system in the world. And lots of corners have been cut along the way.
Just to get this out of the way: all farmed salmon is dyed — otherwise it would be gray, not the pinky orange color we now call “salmon.” That alone would have been enough!
But as I continued to read this book, it seemed like every problem that salmon farmers encountered didn’t give them pause and prompt them to put things on hold until they could figure out a better, less harmful way (to the fish themselves or the ecosystem) to get the results they wanted.
So when farmed salmon started escaping from their pens and people began to worry that they would interbreed with wild salmon, the response was to breed sterile salmon that wouldn’t be able to mate with the wild stock. So triploid salmon were bred (they had 3 copies of every chromosome instead of two). These salmon became so covered with ulcers or developed curved spines and other abnormalities that they died, numbering in the millions.
Sea lice are a parasite that sometimes affect wild salmon, hitching a ride to them as they swim by in the sea. But when salmon are in pens, they make easy prey for the lice, who infest the salmon, leaving them with bloody sores all over their skin or eating their skin clean off. And the lice are able to reproduce right at the mouth of the rivers, where wild salmon still come to spawn, infesting them as well. To deal with the lice, the farmers then dumped tons of hydrogen peroxide (bleach) into the fjords, which had the unintended effect of killing or harming the shrimp, lobster, and other fish that also lived in the fjords, causing them to be considered “near-threatened.” Norwegian wild salmon are also near-threatened, and, though not a consequence of farming, the only remaining populations of U.S. wild salmon are in a few rivers in Maine.
Overfeeding of fish also has caused build-ups of nitrogen in the fjords or the ocean, which created harmful algae blooms and subsequent low-oxygen zones, as the algae decayed.
Salmon are fatty (one of the reasons we like to eat them) and harmful chemicals accumulate in fatty tissue. Farmed salmon are fattier than wild salmon, given how fast they grow and how little they move, so they contain higher amounts of toxins like PCBs than wild salmon.
I could go on, and in previous drafts of this, I did! But I don’t want to load up too much on evidence on one side without hearing from others, who see the issue differently and also make compelling points about salmon farming and food production more generally.
Over the decades, though, improvements have been made, according to our old friend Ben Halpern, a professor of marine biology and ocean conservation at University of California Santa Barbara, who studies the environmental impact of food production.
“There are definitely some issues and bad actors but the salmon farming industry as a whole has done a truly amazing job of improving things dramatically,” he said. “A lot of the issues that were quite problematic in the ’80s and ’90s have been addressed substantially,” he said, referring in particular to the overfeeding issue that creates nitrogen pollution, and a dramatic decline in the use of antibiotics for disease control.
One of the other common narratives — the one I was familiar with, about using forage fish to feed fish — he said is a “red herring.” Before the growth of the aquaculture industry, he said, all of the foraged fish went to feed pigs and chickens. Now that number is down to about 20 percent, with the rest going to aquaculture but also things like the production of fish oil and meal for supplements and pet food.
“If you’re angry about foraged fish” for those reasons, he said, you should know that “the efficiency of turning that foraged fish into salmon meat is really high, with nearly a 1:1 ratio” down from 8:1 previously, which holds for all of the industrial scale salmon farms in Norway, British Columbia, Atlantic Canada, Scotland and Iceland. So whether you are talking about forage fisheries or animal welfare, Ben said, if you’re concerned, you should stop eating industrially produced meat and not worry so much about farmed salmon. And most of that foraged fish — about 90 percent — could just be eaten directly by people.
But among the biggest reasons to keep farming salmon, he said. “We have nearly 8.5 billion people on the planet, and we have to feed them, and domesticated animals are really necessary in order to be able to do that,” including farmed fish.
“The environmental footprint of fish farming across many categories” (greenhouse gas emissions, environmental disturbance, nutrient pollution, and water use) “is way better – in terms of a way to feed high quality nutritious protein to humans. Mussels and clams and oysters are much better for the environment, but we’re never going to get the global population to only eat shellfish.”
Most importantly, “there’s no way to grow food without having some environmental harm, but fish farming is one of the best ways to do it.”
And that brings us back to the earlier question: what are the tradeoffs we’re willing to make to eat something, including salmon? Sure, fish farming is better than other kinds of industrial agriculture, but that doesn’t make it good. And many of the people who are eating farmed salmon (wealthy people all around the world, but particularly in the Western hemisphere) aren’t necessarily the people who are in desperate need of protein. In fact, in the U.S., we eat way more protein than we need!
In general, we don’t know what is being traded away on our behalf so that we can have the salmon (or whatever else) we want at the prices we want. But I suspect that many of us wouldn’t be okay with these compromises if we actually knew about them, and now we do. But it shouldn’t be that we have to read a long book to find out about the serious environmental hazards created by just one industry. Producers need to be more transparent, and we need to be more clear-eyed about what we are eating (and doing), rather than burying our head in the fjords so we don’t have to think about it.
When I told Ben that I thought this was a parable about the perils of human intervention, he said, “I would try to divorce it from salmon,” and think about these issues more broadly: “How do we do this in way that is sustainable? For example, with climate change, where people are rushing to technological solution and we need all hands on deck in order to address this, we also need to think about sustainable solutions with lower consumption, engage technology, and adjust behavior.
“I wouldn’t throw out the technological solutions as part of what we need to do.”
I agree with that, but I also hope that, as these issues continue to arise, we keep asking ourselves these questions, and pause every so often to learn and to think before taking on major risks. Fionn Mac Cumhaill did not eat the Salmon of Knowledge only to forget what he’d learned.
This was originally posted on Tatiana’s Substack News from a Changing Planet, a free twice-monthly newsletter about what on Earth is happening, with articles and essays about climate change and the environment.