Crust
Grand Teton National Park
The crusty top on the deep snow is a mixed blessing to hunters like this red fox. It allows the fox to travel across the snow without expending huge energy sinking in. But it is also a crust that this fox must jump through when diving for rodents two or more feet below the surface. To do this, the fox must jump higher and enter vertically to reach the target. There is little room for error. Photo © copyright by Ed Fuhr.