Life in a Cold Desert!
The Dry Valleys lack many of the higher organisms generally considered “interesting”. The mummified seal and penguin remains remind us that the occasional ill-fated visitor makes its way from the sea out to here, as six Adelie penguins did this season. Unfortunately, their attempts at colonizing the barren, frozen lakes have always ended tragically.
On first glance, the Dry Valleys appear to be devoid of life altogether. But after a little while, I came to realize that despite the desert climate and extreme cold, the Valleys are teeming with life. I compare wildlife viewing in the Dry Valleys to looking at one of those 3-D picture books: readjust your eyes and after a while you simply cannot avoid seeing life all around you. Microscopic creatures live in the soils, lichens grow on the rocks, mosses grow wherever the ground is moist, and algal mats line lake and stream beds with their orange-brown coats of accessory pigments.
Green and Orange mats dominate this stream.
Thick orange algal mats line the streambed.
I came here to study the algal mats, which grow in the streams during the austral summer and then manage to survive the winter in a freeze-dried state. These amazing algal communities consist of photosynthetic microbes including cyanobacteria and diatoms, and provide habitat for the lions of the Valleys, the nematodes. The individual organisms found within these mats vary depending on environmental conditions such as streamflow, and they seem to be sensitive to climatic changes, making them a potentially useful tool for gaging ecological impacts of climate change.
Mosses are abundant in seepage areas.
But they’re also just plain cool. They come in four basic colors: red, orange, green, and black, making the streams some of the most colorful places around. Their diversity and complexity never stops amazing me. Knowing that life can persist in such seemingly harsh conditions was always a source of comfort whenever I started to feel a bit isolated
Chlorophyll analysis reveals colored pigments of mats
University of Colorado