Climate change is ruining beer, maple syrup, chocolate — even your favorite Cosby sweater. Now we can add fish to the list. SWELL.

Basically, warming waters make killifish hungrier, according to new research. Then these bitty fish at the bottom of the food chain eat more mercury-tainted food than usual, storing lots of metal in their tissue as a present for everyone up the food chain, from tuna to humans. Mercury: The gift that keeps on giving! (Did we mention it’s increasingly in bird eggs too?)

Quoth the Washington Post:

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[K]illifish at the bottom of the food chain will probably absorb higher levels of methylmercury in an era of global warming and pass it on to larger predator fish, such as the tuna stacked in shiny little cans in the cupboards of Americans and other people the world over.

“The implication is this could play out in larger fish…because their metabolic rate is also increasing,” said Celia Chen, a professor at Dartmouth College in New Hampshire and one of six authors of the study. “Methylmercury isn’t easily excreted, so it stays. It suggests that there will be higher methylmercury concentrations in the fish humans eat as well.”

Lest you think the Minamata Convention on Mercury last week was just scientists in lab coats breaking open thermometers and cackling wildly, that’s where this research was discussed. Oh yeah, they also signed a massively important treaty:

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Delegates from 130 nations at the three-day convention that ended Friday met to sign a treaty that seeks to greatly limit emissions from coal-fired power plants from industrial nations, mining operations in Africa and other sources that pollute oceans.

Good thing no Americans were there because of the government shutdown! (Le sigh.) Who wants a tuna sandwich?

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