By David Spector Gazette Contributing Writer
Many people seem to consider the observation of changing states of matter synonymous with boredom. “Waiting for water to boil” or “watching snow melt” are comparisons made to the least interesting events in life, but naturalists view these events differently. At this time of year, snow melt provides me with many fascinating episodes of nature-watching.
The pattern of snow melt varies from year to year and from snow event to snow event within a season, depending on air temperature, the density of the snow and its history. As drainage increases beneath the crusted surface, furrows start to collapse, often forming a quilted pattern. Warm tree trunks produce circles of bare ground around them, and areas rich in decay (natural piles of leaves or artificial compost) melt snow with the release of stored solar energy from previous growing seasons.
I especially enjoy the diverse and odd signs of life revealed deep in melting snow that has accumulated evidence for weeks or months. Footprints commonly enlarge as they serve as foci for snow melt, and deer and fox tracks can easily come to resemble moose and coyote tracks with such enlargement.
At the end of a recent winter, my lawn was dotted with patterns of little snow mesas: steep-sided pillars that remained as the surrounding snow melted. These were the tracks of a red fox that had hunted across a layer of then-fresh snow, compacting and slightly melting the surface. That snow then re-froze into thin sheets of ice, more resistant to melt and erosion than the surrounding pack. These miniature mesas were produced by the same process that produces more imposing rock formations in western landscapes: the erosion of surrounding softer material leaves behind islands protected by harder caps.
The fox that left the footprints that became mesas offered its own illustration of the phenomenon of differential wear. When I saw this individual it lacked the white tail tip typical of its species. The dark pigment called melanin not only colors hair, but strengthens it, so white hairs are more susceptible to abrasion than dark hairs. A winter of hunting through snow and ice had worn down the more vulnerable white hairs at the tail’s end, leaving this individual marked with a record of its travels.
The hunting fox was also indirect evidence of the presence of small mammal prey on the lawn. More evidence comes with snow melt, which often shows a marbling of squiggly tunnels along the retreating snow line, a sign that voles and other small’ mammals had thrived beneath the snow (or to use the fancy term, in the subnivean habitat).
At the end of winters with long periods of snow cover, the trampled trails of these rodents remain apparent even after the snow is entirely gone. At those times I sometimes find the softball-sized balls of dead grass—vole nests constructed beneath the protective layer of snow. These nests, now vulnerable to foxes, squirrels, crows and other predators, are probably abandoned as soon as they are exposed and replaced with better sheltered abodes. All in all, this is a perilous time to be a small mammal: snow cover is reduced or gone, food supplies are depleted, and new growth isn’t yet providing much food or shelter,
Watching water boil in nature can also be far from boring, as witnessed by the many people who travel to Yellowstone to watch geysers erupt or to Hawaii to watch water sizzle as lava flows into the ocean. The annual drama of snow melt, though, is something I can watch in my own front yard.
Each year is different, with a different history of snow cover and temperature, with conditions that often differ dramatically over a few miles. The differences in snow melt never fail to captivate me as I watch the unfolding of short histories, miniature versions of the long fossil record.
David Spector is a former board president of the Hitchcock Center for the Environment and teaches biology at Central Connecticut State University.
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