Changes in technology have helped not only with reducing the sense of isolation but in capturing new data about snow leopards. Working with a PBS crew on the 2005 "Nature" documentary "Silent Roar," Jackson used infrared motion- and heat-sensing equipment to get never-before-seen footage of the cats hunting, marking their territory, and mating, as well as footage of a mother with her cubs.
With his glasses and quiet voice, Jackson may not look much like an action hero, but "tough" is the adjective most frequently applied to him by those who have worked with the South African-born conservationist.
"Unassuming" is a close second.
"I think he's got to be one of the toughest guys in the world," says Michael Crowther, president and chief executive officer of the Indianapolis Zoo. The zoo administers the Indianapolis Prize, which has sometimes been called the Nobel Prize of animal conservation. Nominees must prove that, thanks to their work, a species has a better chance of survival. Jackson has been a finalist three times, most recently in 2012.
Jackson spends several months out of every year climbing in the Himalayas. The high altitude, spare living conditions, and grueling regimen would be tough on anybody. But, added to all that, Jackson doesn't like heights, Mr. Crowther says.