Modern day cowboys drive cattle in Colorado
Cowboy David Thompson walks with his dog, Fang, to catch horses that he will use for a day of gathering cattle near Ignacio, Colorado, June 11, 2014. The land where the cattle graze is leased from the Forest Service by third-generation rancher Steve Pargin. Several times a year, he and a crew led by his head cowboy, David Thompson, spend a week or more herding cattle from mountain range to mountain range to prevent them from causing damage to fragile ecosystems by staying in a single area too long.
Grazing on federal land
Rancher Steve Pargin, left, holds a young border collie that cowboy David Thompson had brought while they prepare to gather cattle near Ignacio, Colorado, June 10, 2014.
Grazing on federal land
Cowboy David Thompson carries the reigns of a horse's headstall while preparing to gather cattle near Ignacio, Colorado, June 10, 2014.
Grazing on federal land
Cowboy David Thompson puts a horseshoe on a horse's hoof as he prepares for a week of gathering cattle near Ignacio, Colorado, June 9, 2014.
Grazing on federal land
Cowboy David Thompson drives his truck to join with a group of other cowboys to gather cattle near Ignacio, Colorado, June 10, 2014.
Grazing on federal land
Cowboys ride their horses after eating lunch near Ignacio, Colorado, June 11, 2014.
Grazing on federal land
A rodeo champion buckle adorns the belt of cowboy Stetson Mackey as he waits to begin a day of gathering cattle near Ignacio, Colorado, June 11, 2014.
Grazing on federal land
Cowboys, from left: Grant Gunn, Jody Mangus, Mead Gonzalez, and Georgie Dittmar push cattle through a gate after pushing them across Highway 160 near Ignacio, Colorado, June 12, 2014.
Grazing on federal land
Cowboys Rollo Mangus, left, and David Thompson work to move a large group of calves up a trail during a week-long operation to gather cattle near Ignacio, Colorado, June 11, 2014.
Grazing on federal land
Rancher Steve Pargin and cowboy David Thompson, right, talk with the rest of the crew during a cattle drive near Ignacio, Colorado, June 12, 2014. The land where the cattle graze is leased from the Forest Service by third-generation rancher Steve Pargin. Several times a year, he and a crew led by his head cowboy, David Thompson, spend a week or more herding cattle from mountain range to mountain range to prevent them from causing damage to fragile ecosystems by staying in a single area too long.
Grazing on federal land
A horse bucks as it tries to run from a saddle that had become loose during preparations to gather cattle near Ignacio, Colorado, June 12, 2014.
Grazing on federal land
Cattle cool down and drink water at a man-made reservoir in the mountains near Ignacio, Colorado, June 11, 2014.
Grazing on federal land
Cowboys, from left: Stetson Mackey, Wyatt Williams, and David Thompson rest in the shade of a pine tree after lunch near Ignacio, Colorado, June 11, 2014.
Grazing on federal land
David Thompson uses a rope and stick as he moves a large group of calves up a trail near Ignacio, Colorado, June 11, 2014.
Grazing on federal land
Cowboys David Thompson and Wyatt Williams release a calf after giving it medicine near Ignacio, Colorado, June 12, 2014.
Grazing on federal land
Cowboy David Thompson separates cattle from each other in a pen near Ignacio, Colorado, June 12, 2014.
Grazing on federal land
Cowboy David Thompson looks down on a large herd of cattle during a week of gathering cattle near Ignacio, Colorado, June 12, 2014.
Grazing on federal land
Cowboys Wyatt Williams, right, and David Thompson restrain a calf in order to give it medicine near Ignacio, Colorado, June 12, 2014.
Grazing on federal land
A cow inspects cowboy David Thompson as he rests on the ground near Ignacio, Colorado, June 11, 2014.
Grazing on federal land
Cowboy David Thompson talks on the telephone while eating dinner at the end of the day during a week-long operation to gather cattle, near Ignacio, Colorado, June 11, 2014.
Grazing on federal land
Cowboy David Thompson prepares dinner for himself near Ignacio, Colorado, June 11, 2014.