Look away if you’re eating, because this is truly disgusting. Didymo (code name: rock snot) is an algae bloom that looks like barf mixed with mucus. When it first showed up in eastern Canada in 2006, people assumed it was an invasive species, BECAUSE IT IS SO TERRIFYING. (Conventional wisdom was that fishers were accidentally spreading it by tromping around with their dirty boots.)

Nope! Turns out it’s native — it was just sleeping all this time, and climate change woke it up!

The most severe didymo bloom ever recorded in eastern Canada, photographed in the Duval River in 2013.

Michel ChouinardThe most severe didymo bloom ever recorded in eastern Canada, photographed in the Duval River in 2013.

Writes CBC News:

Grist thanks its sponsors. Become one.

The algae is a concern for fish populations such as Atlantic salmon, as it lines river bottoms, hiding food and making it more difficult for some species to forage.

“It’s like a really bad seventies shag carpet,” said University of New Brunswick graduate student Michelle Lavery.

Rock snot is actually much older than everyone thought. It’s been found in soil samples as far back as 1896. But because lakes were cooler back then, nature’s boogers stayed up its nose (if you will). Now Canada needs one hell of a hanky.