On a cool, wet July morning at the Rocky Mountain Biological Lab in Gothic, Colorado, thick clouds erased the hulking mountains from view. The former mining town is a working summer camp for scientists. Brad Taylor, a Dartmouth professor, met his wife here. She studies bees, and he studies fish, the bugs they eat and the algae that set the bug buffet.
These days, he’s especially preoccupied with one kind of algae — an enigma that haunts wild rivers worldwide. Wearing a blue rain jacket and an orange baseball cap over salt-and-pepper hair, Taylor stood in a bubbling stream on lab property, his eyes searching the rocks for Didymosphenia geminata. Didymo (pronounced “Did-i-mo”) is a single-celled algae or “diatom.” Diatoms are among Earth’s most common life forms and the foundation of aquatic food webs. They’re only visible through microscopes, but if you’ve ever slipped on a slimy river rock, you’ve encountered them.
Less than a decade ago, however, Didymo became much easier to spot here. The cells began sprouting stalks about the thickness of human hairs that coalesced into sprawling underwater manes, which felt like wet, dirty wool. They did the same in Colorado, Idaho, Wyoming, Montana, South Dakota, Connecticut, West Virgina, Canada, Chile, New Zealand, Poland. The algal mats smothered streambeds for miles. They were inconvenient, threatening and gross — described, in scientific journals, as “mucilaginous.” In the popular press, Didymo was dubbed “rock snot.”
View original article at: The case of the snotty streams