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35.5 percent. That’s how much of the world’s assessed fish stocks are now being overfished into collapse, according to the FAO’s most comprehensive marine assessment ever published — released in June 2025, analyzed by 650 experts in 90 countries. More than one in three. And rising by approximately 1 percent every year.
But the package said “Certified Sustainable.” There was a little blue oval. Three fish. The Marine Stewardship Council’s seal of approval, stamped on shrimp from trawlers dragging weighted steel doors across the seafloor, on tuna caught with nets that kill dolphins by the thousand, on salmon from fleets operating in regions where two-thirds of stocks are in freefall.
I used to believe it. I stood in supermarket aisles thinking I was making the smart choice. Fish, not factory-farmed chickens. A lighter footprint. The responsible option for someone who wasn’t ready to go all the way yet.
That was before I read the WWF report.
The World Wildlife Fund — which co-founded the MSC in 1997, which helped build the certification system it was about to dismantle — produced a document describing “troubling, systemic flaws” in the program. Leaked. Damning. The organization that created the standard was publicly doubting its own creation. And in February 2025, Greenpeace went further, declaring the MSC label “absolutely untrustworthy” for consumers.
Here’s why: the logo that’s supposed to tell you something is sustainable charges a licensing fee of 0.5 percent of wholesale value to every company that uses it. The MSC is financially dependent on certifying fisheries as sustainable. That’s not a technicality. That’s the whole story.
The Numbers They Don’t Lead With
In June 2025, the FAO — the United Nations Food and Agriculture Organization — released its most comprehensive assessment of global marine fish stocks ever produced. It analyzed 2,570 individual fish stocks, drawing on data from 650 experts in more than 90 countries. This was not a back-of-the-envelope estimate. This was the clearest picture of the ocean we’ve ever had.
Here’s what they found: 35.5% of all fish stocks are now overfished.
More than one in three. And that’s the assessed figure — stocks we actually monitor, in regions with functioning governance. The ones nobody’s watching are almost certainly worse.
In the Mediterranean and Black Sea, it’s not a third. It’s 65 percent of stocks being fished unsustainably. Two-thirds of all fisheries in one of the world’s oldest fishing regions. Along the northwest African coast — Morocco to the Gulf of Guinea — over half of all stocks are overfished, with little sign of recovery.
And overfishing globally has been rising by roughly 1 percent per year. That’s not a plateau. That’s a trend line pointing in one direction.
Our World in Data’s overview of global fish stocks shows clearly how decades of industry claims about “sustainable management” have coexisted with steady, measurable collapse. The data doesn’t require interpretation. It just requires looking.
What You’re Not Supposed to Think About at the Fish Counter
I want to talk about bycatch.
When someone tells me they “eat fish, not meat,” they’ve almost certainly never sat with the bycatch numbers. They’ve pictured a fishing boat, a net, some fish. Clean. Targeted. Efficient.
The reality: roughly 40 percent of everything pulled from the ocean in commercial fishing operations is bycatch — marine life that wasn’t the target. Dolphins. Sea turtles. Sharks. Seabirds that dive for fish and get entangled in gear. Juvenile fish that haven’t reproduced yet. According to NOAA, the global figure runs to approximately 38 million metric tons of bycatch every year. Some estimates put it at 63 billion pounds.
These animals aren’t carefully sorted and released. Many are dead by the time the net reaches the surface — crushed, drowned (yes, dolphins and sea turtles drown in fishing nets), or suffocated. Those that survive get thrown back overboard. The industry calls it “discards.”
More than 650,000 marine mammals are killed by bycatch every year.
This isn’t an edge case. This isn’t a niche problem with a specific fishery. This is structural — baked into how industrial commercial fishing works. The gear isn’t selective. The ocean doesn’t cooperate. And nobody putting a tuna can in their grocery basket is thinking about the sharks that died to fill it.
The Nets That Never Stop
Here’s the detail that moved me from concerned to genuinely angry.
Even when the boats go home. Even when the quota is met and the nets are supposed to be aboard, the killing doesn’t stop.
Between 500,000 and 1 million tons of fishing gear is lost or discarded in the ocean every single year. Nets. Lines. Traps. Ghost gear. It doesn’t decompose — or rather, it takes centuries to degrade. In the meantime, it keeps fishing. Entangling sea turtles. Drowning whales. Trapping seals.
A 2022 study published in Science Advances put specific numbers on it: nearly 2% of all fishing gear is lost annually — more than 25 million pots and traps, 739,000 km of longline mainlines, and thousands of square kilometers of nets now drifting through the ocean indefinitely.
Ghost gear is responsible for harming 66 percent of all marine mammal species. Half of all seabird species. Every single species of sea turtle. The WWF calls it an “immortal menace.”
And abandoned fishing nets make up approximately 46 percent of the Great Pacific Garbage Patch. The floating mass of debris you’ve seen in photos. The thing that launched a thousand anti-straw campaigns. Nearly half of it is fishing gear.
So when someone’s eating shrimp while telling you the real plastic crisis is straws — that’s the math they’re working with.
Your Dinner Just Released More Carbon Than a Transatlantic Flight
Bottom trawling. If you want one image for the destructive machinery of commercial fishing, this is it.
A heavy net, weighted with steel doors, dragged across the seafloor at scale. It scrapes up everything — ancient corals, sponge ecosystems, seabed habitats that took centuries to form. Flattened in minutes. Researchers have documented habitat destruction from bottom trawling for decades. What’s been calculated more recently is the carbon.
The seafloor is a carbon sink. It stores enormous quantities of CO2 that accumulated over millennia — stable, sequestered, out of the atmosphere. Bottom trawling disturbs that carbon store, releasing it back into the water column and eventually the air.
A study cited by National Geographic, Scientific American, and Smithsonian Magazine, with researchers including those from NASA’s Goddard Institute for Space Studies, estimated that bottom trawling releases approximately 340 to 370 million metric tons of CO2 annually — with 55 to 60 percent making it into the atmosphere within nine years.
That’s more than the total annual emissions of Spain. More than Italy. Every year.
This happens in fisheries that carry the MSC blue label. Industrial trawlers certified “sustainable” by an organization that collects half a percent of every sale.
The Pescatarian Escape Hatch (Doesn’t Work)
I’ll say it plainly: pescatarianism isn’t a meaningful ethical position. It’s a negotiation. A way of maintaining most of the comforts of an animal-based diet while signaling concern.
I get why people land there. Giving up chicken and beef feels significant. Fish feels lighter. The animals are underwater, cold-blooded, silent. The suffering is easier to abstract away. They don’t look at you.
But the nutritional argument — that fish are necessary for omega-3s — doesn’t survive examination. Fish don’t produce omega-3 fatty acids. They accumulate them from algae. You can go straight to the algae. You get everything the fish would give you without the bycatch, the ghost nets, the collapsed stocks.
And the environmental logic for fish over beef? The “at least it’s better than factory farming” position? I’d push you toward what I wrote about the corporations running the fishing industry — same playbook, same regulatory capture, same externalization of costs onto public ecosystems and future generations. These aren’t personal choices operating in a free market. As I laid out in the piece on how the meat industry buys its political cover, industries that can dump their environmental costs onto everyone else aren’t competing fairly — they’re subsidized by collapse.
Fishing is no different. The subsidy is just paid in dead ocean floors.
What “Sustainable” Would Actually Require
Here’s where I’ll give the nuance its due, because I think it matters: some fishing, in some conditions, with some methods, can operate within ecologically sustainable limits. Long-line artisanal fishing in well-managed regional fisheries. Certain shellfish aquaculture that doesn’t require wild feed. The FAO data itself shows the Northeast Pacific reaching 92.7% sustainability rates — not because fish are inherently limitless, but because of decades of strict management investment.
Those are the exceptions. They are not what is feeding 8 billion people. They are not what is on supermarket shelves at scale. They are not what the MSC is certifying in volume.
What is feeding people at scale is industrial commercial fishing, operating with gear that kills indiscriminately, certifications that are financially compromised, and an ocean that’s been absorbing the costs — in carbon, in collapsed stocks, in ghost gear, in dead zones — for generations.
No logo fixes that math. No blue oval changes what’s in the net.
So ask yourself this: if fishing were genuinely sustainable — if the certification actually meant something, if the bycatch didn’t happen, if the ghost nets didn’t exist — what would that world look like? It wouldn’t look like a $100 billion global industry operating with self-reported catch data, financially compromised labels, and gear that keeps killing for centuries after the boat goes home.
The next time someone tells you they eat fish “instead of meat,” think about 38 million metric tons of bycatch. Think about 650,000 dead marine mammals per year. Think about a million tons of gear rotating through the ocean for centuries. Think about 35.5 percent of assessed fish stocks in collapse, and that number rising by 1 percent every year.
Then go read what actually happens when you stop eating animals entirely. Not as a purity exercise. Not as an identity. As the only position that’s consistent with “I don’t want to cause unnecessary harm.”
The ocean doesn’t care about your certification. The ghost nets don’t check the quota before they kill.
Share this with the person in your life who eats fish “instead of meat.” They deserve to know what’s actually in the net.
References
- FAO (2025). State of World Marine Fishery Resources 2025 — 35.5% of assessed stocks overfished; Mediterranean at 65%
- Our World in Data. Fish and Overfishing — global fish stock trends and historical context
- NOAA Fisheries. Bycatch — official US government data on bycatch volumes and species impact
- WWF. Ghost Fishing Gear: Ocean’s Silent Killer — ghost gear scope and marine mammal mortality
- Richardson, K. et al. (2022). Global estimates of fishing gear lost to the ocean each year. Science Advances
- National Geographic. Bottom trawling is huge source of carbon emissions, new study reveals
- Greenpeace (2025). MSC and RSPO Absolutely Untrustworthy for Consumers
- SeafoodSource. Leaked WWF report levels harsh criticism of MSC — co-founder’s internal critique of its own creation
- Blue Planet Society. Bycatch crisis: millions of tonnes of marine life slaughtered ‘accidentally’