In this April 20, 2011 photo, provided by the Colorado Department of Parks and Wildlife, a rare lynx is captured by remote research camera, prowling along in the snow of the San Juan Mountains, in southwestern Colo. Scores of lynx roam the remote Colorado high country, 16 years after they were reintroduced to the state. But the elusive animals are rarely seen or photographed. Using automated cameras mounted in trees, researchers are studying where lynx live and how well they're doing, said Eric Odell, manager of Colorado Parks and Wildlife's carnivore conservation program. (Colorado Department of Parks and Wildlife via AP)

Scores of fierce-looking lynx roam the remote Colorado high country, 16 years after they were reintroduced to the state. But the elusive animals are rarely seen or photographed.

Now state researchers have captured photos of lynx as they prowl the San Juan Mountains of southwestern Colorado. Using automated cameras mounted in trees, the researchers are studying where lynx live and how well they're doing, said Eric Odell, manager of Colorado Parks and Wildlife's carnivore conservation program.

Odell estimates 200 to 300 lynx live in Colorado but no one knows for sure. He hopes to get several years' worth of data to track their range over time.

Some key questions about lynx and the monitoring program:

WHAT ARE LYNX?

Lynx are medium-size cats with delicately tufted ears, short tails and broad, kitten-like paws. They can be nearly 3 feet long and weigh as much as 30 pounds. Their big paws work like snowshoes, helping them walk across powdery snow, Odell said. They're widespread in Canada and Alaska but scarcer in the 48 contiguous states, where they are protected as threatened species under the Endangered Species Act. They primarily hunt snowshoe hares.

WHERE ARE THEY IN COLORADO?

In this Feb. 9, 2015 photo, provided by the Colorado Department of Parks and Wildlife, a rare lynx is captured by remote research camera, prowling along at night in the snow of the San Juan Mountains, in southwestern Colo. Scores of lynx roam the remote Colorado high country, 16 years after they were reintroduced to the state. But the elusive animals are rarely seen or photographed. Using automated cameras mounted in trees, researchers are studying where lynx live and how well they're doing, said Eric Odell, manager of Colorado Parks and Wildlife's carnivore conservation program. (Colorado Department of Parks and Wildlife via AP)

Colorado began reintroducing lynx in 1999 after they disappeared from the state in the 1970s because of hunting, poisoning and development. The lynx were captured in Canada and Alaska and released in the San Juan Mountains. The transplanted cats began having kittens by 2003, and Colorado-born lynx have been having kittens ever since. They mostly live in spruce and fir forests above 9,000 feet elevation.

WHY TAKE THEIR PICTURES?

The cameras are part of an effort to see how much of their potential habitat the lynx are occupying. Researchers randomly chose 50 plots of land, each one about 29 square miles, and began monitoring last winter. They also visit more accessible plots on snowmobiles or skis to look for lynx tracks, scat and fur.

WHY NOT JUST COUNT THEM?

Counting lynx is expensive and labor-intensive. Unlike some species, individual lynx aren't distinguishable by appearance, so they have to be captured multiple times to document their status, Odell said. The study is also less invasive.

HOW DO THE CAMERAS WORK?

In this March 14, 2015 photo, provided by the Colorado Department of Parks and Wildlife, a rare lynx is captured by remote research camera, prowling along in the snow of the San Juan Mountains, in southwestern Colo. Scores of lynx roam the remote Colorado high country, 16 years after they were reintroduced to the state. But the elusive animals are rarely seen or photographed. Using automated cameras mounted in trees, researchers are studying where lynx live and how well they're doing, said Eric Odell, manager of Colorado Parks and Wildlife's carnivore conservation program. (Colorado Department of Parks and Wildlife via AP)

The cameras' motion detectors trigger the shutter when animals walk into view. At night, they use an infrared flash so the lynx don't know they're being photographed. Crews seal the battery-powered cameras inside weather-tight cases and mount them in trees before the snow begins to fall and retrieve them after the snow melts. Odell expects to deploy 124 cameras this winter, about the same as last winter.

WHEN WERE THE PHOTOS TAKEN?

Researchers got some photos in 2011. Last winter was the first season for the full study. Odell hopes the state will fund the study for 10 years.

HOW MUCH DOES THIS COST?

The first year of the study cost about $40,000, Odell said.