It was nearing sunset in Grand Teton National Park. I was photographing a string of old barns known as Mormon Row, when a small herd of bison wandered through the prairie. Bison seem to live much of their lives without grace; they grunt and plod and smell and glare. But there are times when their mere presence is transcendent, when they blend with the sagebrush and the hills to become a thing of beauty.

When I photographed these bison, the Grand Tetons were dangerously dry; in fact, the day before I arrived, a thousand acre wildfire had nearly incinerated the campground where I subsequently stayed, and the smell of burnt sage lingered in the air. In this dryness, every step these animals took sent up a cloud of dust. Often, the animal enjoyed a bison spa - rolling around on their backs in the dust.

For photography, the lingering dust hanging in the air was exquisite - especially when backlit by the setting sun.

Lee Rentz