Climate change is making it more dangerous to eat certain fish | Grist
And here’s where climate change comes into play: as waters warm, the researchers found, big fish like bluefin tuna have to expend more energy just to survive, so they end up eating more. Like humans after a workout, their metabolism shoots up, and they simply need more calories. So overheated fish are ending up with higher levels of mercury because they’re eating more mercury-containing food than usual.
So what will happen to seafood guidelines in the future if mercury emissions remain low but ocean temperatures and overfishing keep rising? Researchers say it depends on the fish. Fans of Atlantic bluefin tuna (the canned stuff), for example, should start lobbying for climate action ASAP. While mercury levels in the popular fish have indeed fallen thanks to reduced emissions, warming temperatures will almost entirely reverse those gains by 2030.