The handlers note where the scat is found and take a sample for analysis to determine if it is from a tiger and to check the animal's health.

Sadie's handler, Elizabeth Seely, says they can learn a lot from animal droppings.

"We can get hormone levels, physiological data, disease status," she said. "And, all of it combined will give us an overall population health."

Cambodia's Mondulkiri Forest was once rich in wildlife, including tigers, but hunting and poaching largely emptied the region and killed off almost all the tigers.

Lean Kha was a soldier with the communist Khmer Rouge in the early 1980s and admits he killed wildlife for food and trade, including 14 tigers.

He says he became a forest ranger to make up for what he calls his past sins.

"There were a lot of animals when I was with the Khmer Rouge and less afterwards," he said. "But, since I became an animal protector it seems like wildlife numbers are increasing."

Conservation Canines has teamed up with Cambodian rangers and the conservation group WWF to protect wild tigers. The big cats once roamed throughout Asia, into Siberia, but conservationists say only a few thousand tigers remain in the wild; far more live in captivity. Without immediate action, the WWF says, by 2022, there may no longer be any wild tigers.

Nick Cox, the WWF's Dry Forest and Tiger Program coordinator for the countries along Southeast Asia's Mekong River, says the forests of Cambodia's eastern plains offer an intact habitat for reviving wild tigers.