- Shadow of the Wolf (2017)
- Shadow of the Jaguar (2018)
- Shadow of the Bear (2019)
- Shadow of the Fox (2021)
- Shadow of the Griffin (2023)
Non-Fiction:
- The Making of a Ranger: A Memoir of a National Park Ranger (1995)
- The Ranger Within: Exploring the National Park System with America's Best-Known Ranger (1998)
- The Ranger's Guide to the National Parks: The Official Guide to America's 59 National Parks (2004)
- The Great Smoky Mountains: A Natural History Guide (2007)
- The Yellowstone Reader (2011)
- The Grand Canyon: A Natural History Guide (2014)
- Yosemite National Park: A Natural History Guide (2017)