Instructor Biographies

text: The Grand Canyon Field Institute

Instructor Biographies

Expert Field Instructors

Grand Canyon Field Institute is proud of its outstanding team of instructors. Made up of resource experts possessing PhD's, Masters and Bachelors degrees, our instructors continually share their passion for Grand Canyon with others. The following is a list of instructors that will likely be leading classes during the upcoming season.

If the class description lists the instructor as “Field Institute staff,” one of the following instructors will serve in that capacity. Preclass materials will indicate which instructor has been scheduled for your class, or you can call the Field Institute office for the latest information on specific assignments. All instructors listed, with the exception of Mike Buchheit, Jack Pennington and Elaine Maier, are acting as independent contractors while leading courses and performing duties for the Field Institute. Mike, Jack, and Elaine are full-time employees of the Grand Canyon Field Institute.

Listed alphabetically by last name.
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Tom Myers

Tom Myers is a longtime physician at the Grand Canyon National Park clinic. During his tenure on the South Rim, he has diagnosed and treated thousands of backcountry medical problems. He has been exploring in and around Grand Canyon since 1973 and teaching for the Field Institute since 1994. Tom is the author of Grand Canyon Trail and River Medicine Field Guide and Over the Edge: Death in Grand Canyon. He is also coauthor of Grand Obsession: Harvey Butchart and the Exploration of Grand Canyon.

Sherri O'Neil

Sherri grew up in Connecticut backpacking the Appalachian trail, but when she began backpacking in the Grand Canyon in the early 90's, she knew she wanted to live and work there. She lived at Grand Canyon for nearly a decade and in that time worked for the National Park Service as an Interpretive Ranger and also as a Backcountry Ranger; both positions allowing her to pursue her passion for the Canyon and its trails. In her time at the Grand Canyon Sherri has hiked 1000's of miles and led ranger programs and tours on Archaeology, Ethnobotany, and Geology. Sherri's additional canyon experience includes rafting the Colorado River during science research projects, and studying Anthropology and Archeology at Northern Arizona University. Besides leading Canyon trips Sherri is a silversmith and a certified yoga teacher.

Jack Pennington

Jack Pennington received his education in his native England, earning a B.S. in geology from Queen Mary College (London) and an M.S. in mineral exploration and mining geology from Leicester University. Geology has taken Jack across much of the globe. He traveled to Africa where he worked as an exploration geologist at the world famous Ashanti mine in Ghana, and visited South Africa’s and Swaziland's rich mining districts. He also studied the geology of the UK and much of Europe. Jack came to Grand Canyon National Park in 1994 working first as a volunteer naturalist with the Division of Interpretation and then as a restoration specialist (plants) with Grand Canyon’s Science Center. He has been down the Colorado River almost a dozen times each time assisting with science research projects.

Alan Petersen

Alan Petersen has been drawing and painting Grand Canyon since forty years. He worked on the Canyon’s South Rim for several years before moving to Flagstaff to study at Northern Arizona University in 1980. Alan’s connections to the Canyon run deep – literally; he worked as a river guide on the Colorado River in Grand Canyon for eight years. More recently, in his role as the Curator of Fine Arts at the Museum of Northern Arizona, Alan has curated exhibitions of work by such notable artists as Gunnar Widforss, Joella Jean Mahoney, Mary-Russell Ferrell Colton, Merrill Mahaffey, Bruce Aiken, and Ed Mell.

Currently, Alan is working on a book on Gunnar Widforss’ life and art, and a catalogue raisonné of Widforss’ paintings. He is also working on a comprehensive monograph on painter Merrill Mahaffey. In addition, Alan teaches art history, painting, and courses pertaining to the Colorado Plateau region at Coconino Community College in Flagstaff. His own paintings have their source in the light, space and landforms of the Colorado Plateau, and explore the formal relationships between color and pictorial space.

Andre Potochnik

Andre Potochnik is a Flagstaff-based geologist, educator and river guide with a doctorate in geology from Arizona State University. Andre’s inspiration in geology and rivers stems from working as a river guide in the Grand Canyon since 1973. His interest in conservation of natural resources spurred his involvement with Grand Canyon River Guides, where he currently works as river science coordinator. For the past eight years, Andre has also served on the Adaptive Management Work Group to improve operations of Glen Canyon Dam for the benefit of the river ecosystem in Grand Canyon. Andre has held lectureships at Arizona State University, Northern Arizona University, Yavapai College and Prescott College. He also develops river guide and interpreter-training seminars and teaches outdoor public education classes through the Grand Circle Field School, Elderhostel and other groups. Andre is currently organizing and leading a group of educators from across the nation to advocate for education-based river trip access to Grand Canyon National Park. Today, he continues to integrate research, policy and education on Colorado River and Grand Canyon issues.

Wayne Ranney

Wayne Ranney has been intimately associated with the canyon since 1975, when he worked as a backcountry ranger near Phantom Ranch. He is a professional geologist, writer, river and trail guide and educator with a specialty in interpreting the landscape evolution of the Grand Canyon and the Colorado Plateau. Notable books by Wayne include Carving Grand Canyon, Ancient Landscapes of the Colorado Plateau and Sedona through Time. Wayne has an easygoing leadership style that blends well with his knowledge, experience and love of the Grand Canyon. Participants who attend his classes come away with not only a clearer understanding of how this landscape may have evolved through time but an appreciation for how humans beings have interacted with it and have been shaped by its power and sublime beauty.

Glen Rink

Glen Rink is a master botanist and an avid birder with a bachelor’s degree in geology and a master’s degree in biology from Northern Arizona University. He has over 22 years of river and hiking guiding experience in remote desert wilderness settings. Glen has been a Grand Canyon river guide since 1981 and has rowed river trips in Central America.

Frank Romaglia

As a Southwest Airlines captain, Frank Romaglia flew over the Grand Canyon hundreds of times and finally decided to change venues and spend more time at the bottom. Putting his organismal biology degree from Rutgers to work, Frank has been guiding for outfitters and Elderhostel for the last seven years. He also leads educational hikes and teaches for McDowell Sonoran Conservancy and Fountain Hills Conservancy. Frank volunteers for Project Great Outdoors, taking underprivileged children river rafting in the Sierra Nevada. He has also been a part of numerous National Park Service archaeological and biological research projects.

Amanda Sahli

Amanda grew up in Los Angeles, California, but knowing that the city life was not her destiny, immediately after high school she moved to the closest university to the Grand Canyon, Northern Arizona University, where she studied literature and art history. She also studied Spanish and International Literature in Mexico and New Zealand. For over 15 years Amanda has lived in the Grand Canyon area studying, exploring , teaching, guiding, and more exploring. Amanda's goal in guiding is to help people understand and enjoy nature and to help them become sustainable lifelong learners. She spends winters living and working at Phantom Ranch at the bottom of the Grand Canyon, and summers on the South Rim leading tours. When not sharing her passion of the region with others Amanda enjoys making art and traveling the world finding new trails to hike and bike and new rivers to raft.

Christa Sadler

Christa Sadler has worked with the Field Institute since its inception in 1993. She is a geologist, educator and naturalist with a serious addiction to rivers, deserts and mountains. She has pursued research in archaeology, geology and paleontology across much of the globe, including searching for dinosaurs in Montana, fighting off dust storms and overly curious camels in the Gobi Desert of Mongolia and steering clear of annoyed marine iguanas in the Galapagos Islands. Christa teaches geology and guides in the canyons and on the rivers of the Southwest in the spring and fall, and escapes to Alaska in the summers. She also runs This Earth, a small business that takes geology and fossil programs to children around the country, and designs Earth science exercises, programs and field trips for students in grades K–12. Christa’s writing and photographs have appeared in Plateau Journal, Sedona Magazine and Earth Magazine, and she is the author of Life in Stone and the editor of the anthology There’s This River … Grand Canyon Boatman Stories.