Wildlife photography of a Red Fox slinking past an American Bison lying in snow in Yellowstone National Park

A Red Fox trots past an obviously annoyed bison as he searches for rodents the herd has displaced. While generally solitary, nocturnal, and rarely seen, foxes increase their daylight activity in Winter to find enough food. Bison displace snow with their massive heads in search of grass, where they disrupt tunnel systems that small rodents dig under the snow for protection, warmth and ready access to unfrozen grass, leaves, seeds, and insects.  When the tunnels are destroyed by foraging bison herds, mice and voles scamper across the top of the snow or die in collapsed tunnels. But to a daring red fox, either outcome means a badly needed Winter meal.