On the way home from Old Faithful today, my co-workers and I witnessed a lengthy line of cars that stretched nearly five miles past the Madison junction; in Yellowstone this is referred to as the infamous “bison jam.” A large herd of bison marched confidently on the paved road, some peering curiously through our car windows as they passed. The calves--some just beginning to sprout the first sign of horns--trotted and played among the adults.
It’s been fun watching the once small calves develop these past few months. The small buds of horns are now showing, and they are developing muscles, most notable in the shoulder region. According to the NPS’s publication Yellowstone Resources and Issues 2008, the bison’s “massive hump supports strong muscles that allow the bison to use its head as a snowplow in winter, swinging side to side to sweep aside the snow.”