What America Lost When It Lost the Bison
By migrating in huge herds, bison behave like a force of nature, engineering and intensifying waves of spring greenery that other grazers rely on
By Ed Yong
Chris Geremia was surprised. After considerable effort, and substantial risk to life and limb, he and his colleagues finally had the results from their decade-long experiment, and those results were both clear and unexpected: Bison do not surf.
Specifically, bison (or buffalo) don’t follow the waves of new shoots that burst from the ground every spring. This phenomenon, known as surfing the green wave, allows animals to eat plants at their most nutritious, when they’re full of nitrogen and proteins and low in indigestible matter. Such freshness is fleeting, and so grazers undertake large migrations to track the new greenery as it crests across the landscape. Over the past decade, scientists have shown that mule deer, barnacle geese, elk, elephants, Mongolian gazelles, and a dozen other species all do this. Geremia wanted to see whether bison, which once formed the largest grazing herds in North America, follow the same pattern.
Beginning in 2005, he and his colleagues started putting GPS collars on bison in Yellowstone National Park, home to the…
