Rock snot in a river in SpainWIKIMEDIA, DAVID PEREZThe not-so-affectionately named “rock snot,” a freshwater algae species that can carpet riverbeds with globular mats, is becoming more common around the globe because environmental conditions are favoring its growth, not because it is being introduced into new watersheds, according to US and Canadian researchers.
The algae, Didymosphenia geminata, or “didymo” for short, has been cropping up in rivers in New Zealand, South America, Canada, and the United States in recent decades, and researchers had previously thought that it was an invasive species hop-scotching around the globe, introduced into new watersheds by human hands (or, more likely, boots). But Dartmouth College ecologist Brad Taylor and Max Bothwell of Environment Canada suggested that the more likely explanation was that didymo is native to all those rivers and is just blooming because of changes in environmental conditions, such as the climate change-related nutrient paucity and decreased ice cover. In particular, Taylor and Bothwell wrote in a paper published Wednesday (May 7) in BioScience, decreased phosphorous could be promoting the excessive production of ...
