Life in the Valleys
From “Open House for Butterflies” by Ruth Kraus and Maurice Sendak
Whether or not they intended to, perhaps the beloved Kraus and Sendak offered important scientific advice. Ground-time in the field, particularly when logistics involve helicopters transport and unpredictable weather, is truly precious. We fill pages of notebooks in anticipation of our field work– detailed schedules, lists of goals, back-up plans. Then we step off the helicopter and the proverbial timer starts. We have 1 week, or maybe 5 days, or often 4 hours to make all those plans happen. Whatever the case, it’s difficult to escape the urgent pressure to make every second count. But one of many gifts in working with a partner in the field is that we may remind each other to stop for a moment, and dedicate some time to quietly observing our incredible surroundings. In this spirit, Ruth and I designated our first task to becoming “acquainted” with the valley.
Ruth sits perched on a hilltop in the center of the expansive valley, taking it all in.
Vibrant mats appear along streams, even a shallow trickle such as this one.
As we walk around, one of the most prominent features is the myriad of twisting little streams. Some are audible if you are very quiet, though often the wind drowns that out. We stumbled across tiny ones, requiring me to squint inches away to even tell it was moving, and others that were wide enough we were unable to cross. From the helicopter they are hardly visible. Yet they create an extensive network of interconnecting waterways, like arteries, weaving in and out of ponds and feeding vital resources to a desert landscape. As we get close, colors and textures began to stand out. Along the stream edges, colorful mats, and sometimes even moss patches, grow in thick clumps.
It seems strange at first- finding red, green, and orange life forms in a desert like this. But as water penetrates the ground underneath the stream bed (called the ‘hyporheic zone’), a damp area is formed adjacent to the stream. This allows for things like algae, cyanobacteria, and microbes to be active in these wetted areas. In this way, water bodies can be extremely influential on where, when, and what types of organisms thrive in the valley.
Black and orange growth at the shoreline of a pond reveals underwater bubbles, a sure sign of physiological activity.
Many of these streams are currently monitored by researchers in the LTER project, where they examine flow rates, sediment discharge, water chemistry, and composition of the biological communities.
A patch of moss grows in a spot perhaps moistened by melted snow
While Ruth sampled soils throughout the valley, I’ve been focusing on the water. Water bodies here are unique for many reasons. One of which is that many of them are frozen most of the year. These harsh conditions limit the underwater community to just the hardiest species, and many cyanobacteria excel at just this. With abilities such as withstanding freeze-thaw cycles, these organisms are of particular interest to me. So while I’m here I am collecting water from lakes, ponds, and streams, and when I return to Dartmouth I will analyze these samples, including things like who’s living there, in what abundances, and their potential for toxic metabolite production.
Even under the ice, layers upon layers of leafy mats are able to scavenge enough light and thrive.
Under the water of a small pond on Hjorth Hill reveals a productive world of algal and microbial mats.
For a frozen desert landscape, it’s incredible how much life persists here. We are back in McMurdo now, but eagerly await our next adventure. Hopefully this week! Until then, thanks for your interest!
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