A disabled Vietnam veteran and Green Beret medic, Peacock was the real-life model for Edward Abbey's George Washington Hayduke. He has published widely on wilderness issues ranging from grizzly bears to buffalo, from the Sonoran desert to the fjords of British Columbia, from the tigers of Siberia to the blue sheep of Nepal.

Peacock was named a 2007 Guggenheim Fellow and a Lannan Fellow for his work on a new memoir about archeology, climate change and the peopling of North America.

He lectures regularly about wilderness and veterans issues, often at schools including The Hotchkiss School, California Academy of Sciences, Scotts Community College in Iowa, Texas A&M, Middlebury College, University of Minnesota, Ohio University, University of Montana, The Thacher School, University of Kansas and many others.

Doug was the subject of a feature film about grizzlies and Vietnam, Peacock's War, which premiered on PBS's Nature and the Discovery Channel, and won the grand prizes at the Telluride Mountainfilm and the Snowbird film festivals. He has appeared on television shows including the Today Show, Good Morning America, NBC Evening News, PM Magazine, Sesame Street, American Sportsman and Democracy Now.

Doug co-founded the Wildlife Damage Review, Vital Ground and Round River Conservation Studies, and is an active member of the board of directors for Round River Conservation Studies and the Raincoast Conservation Society, whose efforts are directed toward the conservation of large landscapes. Raincoast works primarily on the British Columbian coast, forging an alliance with First Nations to change logging practices, end salmon farming and trophy brown bear hunts. Round River labors on a larger scale, working with indigenous people and governments in Africa, North, South and Central America to develop region-wide conservation strategies protecting and enhancing intact ecosystems (simultaneously training college students--who perform much of the field work--in environmental sciences).

For his service in Vietnam, Doug was awarded Soldier's Medal, the Vietnamese Cross of Gallantry, and the Bronze Star. He lives in Emigrant, Montana.