In Yellowstone National Park, bison are the most commonly seen form of wildlife. They are well suited for the harsh winter conditions in the park, which can reach extremely cold temperatures over long periods of time. The bison often will congregate near the rivers and geothermal features, which can provide some warming relief from the cold. On very cold mornings, this provides opportunities to capture what I have always believed was one of THE iconic images of Yellowstone, bison covered in frozen steam. Similarly, deep snow pack conditions provide opportunities for another iconic Yellowstone image, snow covered faces of bison searching for vegetation. To me, these images capture the essence of their struggle to survive in this wild and challenging landscape.