"Never in all our wildest dreams did the small group of scientists who worked in Tanzania's national parks [in the 1960s] imagine that men armed with automatic weapons would one day stride through the national parks. It was just not in our thinking," he says of the heavily armed poachers who had moved in.
The soft-spoken conservationist now lives in Kenya with his wife, Oria, who co-founded Save the Elephants. Together they have written two books, "Battle for the Elephants" and "Among the Elephants."
During the height of the ivory poaching, Douglas-Hamilton rode in small planes wearing one flak jacket and sitting on another as he helped park rangers in Uganda bring back elephants from the brink of extinction. He's been repeatedly shot at and has survived plane crashes, droughts, floods, malaria, and once, being squashed by a rhinoceros.
He campaigned for years for a worldwide ban on ivory sales, which finally took effect in 1989.
His long-term commitment to saving elephants across Africa impressed the prize jury, says Michael Crowther, president and CEO of the Indianapolis Zoo, which administers the prize. Douglas-Hamilton pioneered the first scientific study of elephant social behavior, Mr. Crowther says.
Among his discoveries: Elephants have a matriarchal society and travel in families.
"He has been creative, committed, and consistent," Crowther says. "And he's been courageous – politically courageous and physically courageous."