The effects of climate change aren’t always massive storms and never-ending drought. Sometimes they happen quietly, over many years, before finally surfacing in all their disgusting, stomach-turning glory. Case in point? Rock snot. Since 2006, folks in Canada have been noticing a thick, mucous-like substance spreading across the bottom of rivers and streams. Like the common name suggests, this nasty mass of sliminess looks exactly like what might happen if a rock caught a nasty cold and then sneezed without a tissue. For a long time, scientists assumed it was an invasive species, but it turns out it’s actually a type of algae that’s kicked into high gear thanks to changing weather patterns.

The scientific name for “rock snot” is actually Didymosphenia geminata, or ‘didymo’ for short. It’s a species of diatom that grows in freshwater rivers and streams with consistently cold water temperatures. For a long time, wildlife experts thought it was an invasive species spread through contaminated fishing gear.

However, it’s recently been confirmed that rock snot didn’t migrate to North American via a dirty fishing boot. Instead, “it appears to be a native species that was once subdued by cooler temperatures, but is now proliferating because of global warming,” reports CBS News. It’s been known in Canada since the late 1800s, but didn’t begin to cause problems until the early 1990’s (hmm, just about the time we started hearing about climate change).

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When left to its own devices, rock snot can alter stream ecology by forming dense algal blooms that can cover up to 100 percent of stream bottoms. “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,” explains CBS.

It’s thought that because the average temperature of the planet (and thus the waterways) was cooler back in the 1800s, rock snot rarely caused enough commotion to be noticed. But now, thanks to all those fossil fuels wrapping the Earth up in a warm, fuzzy blanket, there’s nothing to keep the nasty algae from taking over. Scattered populations exist throughout the United States, including New England, the Mid-Atlantic Region, and the Western U.S., and have even been found in New Zealand and South America.

Via Grist

Images David Perez, teresatrimm, USGS

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