Red Snow, Green Snow

Abstract

M icrobiologist Brian Duval hates this part, so let's just deal with the snickering up front. Yes, he studies yellow snow. He also studies red, green, and orange snow and would love to examine other colors if he were lucky enough to discover them. His palette comes from springtime blooms of algae that live only in deep, persistent snowfields. And yes, even a professional sometimes gets fooled. was outside a penguin rookery in Antarctica, and I thought I was collecting this greenish-yellow algae, recalls the microbiologist now at the Massachusetts Department of Environmental Protection in Worcester. was saying, 'Yeah, yeah, this looks like the stuff.' When he checked his treasures under a microscope, however, he diagnosed the obvious nonalgal origin. It gets embarrassing, he admits. Despite the yellow-snow raillery, Duval and his colleagues stay with their studies of snow algae because of the marvels of the chilly lifestyle. Somehow the 350 species of snow algae thrive in the near-freezing, nutrientpoor, acidic, sun-blasted slush of melting snowfields around the world. The algae support a food web in the snow-a world of tiny, wormy, crawly beings as odd as Spielberg-movie creatures. Algal life cycles combine the drama of salmon runs and the nightmare of icebound explorers. Snow-algae chemistry captivates biologists musing about life on other planets or prospecting for novelties on our own. These flashy algae are on their way to becoming glamour species in what Duval and like-minded specialists see as the dawning of a great era of snow ecology. Plus, snow algae can be gorgeous. In high Western snowfields, they blush red in footstep-size patches and meters-long streaks that hikers call watermelon snow. In northern New England, they give salmonorange sunset streaks to the last mounds of snow at the season's end. Fie on snickering. Such wonders deserve awe. They're amazing, Duval sums up. He doesn't say that they're cool. That's another one that he's heard too often. S now algae aren't ice algae. Many of the ice species tolerate salt water and survive in solid ice packs at the poles. They're completely different species, Duval says, sounding a little surprised that anyone would want to lump the groups together.