George Monbiot, a columnist for the Guardian, penned an OpEd titled "Stop eating fish. It’s the only way to save the life in our seas" that described the dangerous effects that a nearly unregulated fishing industry has caused catastrophic damage to our seas.
When people think of fishermen, they think of "someone who looks like Captain Birdseye: white beard, twinkly eyes, sitting on a little red boat chugging merrily across a sparkling sea?" But the reality is that the vast majority of fishing fleets are controlled by five wealty families. They own massive armadas of ships and use huge nets to essentially sweep the seas clean of all fish.
The oceans are bearing the brunt of climate change and they're 70% of the world's surface area. Plastics and other manmade waste are changing the very chemical composition of the water, but the fishing industry is doing tremendous damage as well. The industry has a lot of lobbying power, enough to keep the negative effects of their practices out of environmental documentaries like David Attenborough's Blue Planet Live series. Meanwhile, these shipping fleets are picking the ocean clean and depriving the waters around poor nations of their major source of protein, while wiping out sharks, tuna, turtles, albatrosses, dolphins and much of the rest of the life of the seas. Coastal fish farming has even greater impacts, as fish and prawns are often fed on entire marine ecosystems: indiscriminate trawlers dredge up everything and mash it into fishmeal.
In international waters, the lengths that industrialized fishing operations go border on tragic, with 75-mile long hooks that sweep the fish and predators clean from the waters, but even national waters, which are supposed to be better regulated, suffer from bad oversight.
The government claims that 36% of England’s waters are “safeguarded as marine protected areas” (MPAs), but in reality it's a meaningless term. Commercial fishing is excluded from less than 0.1% of these fake reserves. What's worse, a recent paper in the Science journal found that the trawling intensity in European protected areas is higher than in unprotected places. So if you're a fish, you're better off being off the reservation. In the meantime, these fake laws exist to look like something is being done about the problem.
The weird thing about this all is that there's a real chance that if commercial fishing in the high seas were banned or deeply regulated, the actual amount of fish caught in the world might well be bigger. Without the ocean-scouring effects that these industrial fleets have, stocks could replenish and bigger fish populations would move inland towards national waters. Without it, the relentless drive to keep our fish and chip restaurants filled will do tremendous damage to the ocean.
So until sensible regulation is passed, you have to think carefully about the fish you consume.