Gros Ventre Wilderness, Wyoming, USA

A camera trap set up at the mouth of a cave captures a female cougar and her cub seeking refuge from the cold.

Cougars, once in decline, have for the past 40 years been making a comeback across the western United States—though they remain extremely elusive. The cats are protected in California and Florida, but prized game in 13 other states. The success of the recovery in cougar numbers depends in part on where the public will tolerate them, and on strategies for dealing with the difficulties of interaction between humans and cougars in populated regions.