When you join us in a program or attend one of our many free events, you will get to meet some of the most knowledgeable guides in the area. Our guides are passionate about Yosemite and love to share their experiences.
KAREN AMSTUTZ A California native with a Masters in Environmental Education, Karen has been in Yosemite for over 15 years. She has taught for NatureBridge (formerly Yosemite Institute) and has worked as an NPS ranger in Tuolumne Meadows for many summers. She is well-known for her campfire programs on ravens. Karen lives with her family in El Portal.
SCOTT BORDEN was a faculty member for two years at NatureBridge (formerly Yosemite Institute) before becoming the Mentor Teacher overseeing science and service-learning projects. He is a rockclimber and naturalist with a love of the outdoors.
JON BYERS did his first backpack trip in Canyonlands at age four and has always loved wild country. He’s been a member of the NatureBridge (Yosemite Institute) faculty for the last few years and has taught programs for the Conservancy since last summer. Originally from Colorado, Jon studied geology and ecology and has recently been learning HD videography. He is a co-founder of the Alpine Americas Project, a citizen effort to survey climate changes in the Sierra and the Andes.
WAYNE CHRISTENSEN is a local astronomer with a passion for the clear skies of the Sierra. He grew up in Los Angeles but was mesmerized by the stars on family trips to Pinecrest. Wayne lived in Hawaii for many years, where he was president of the Hawaii Astronomical Society. He lives near Sonora, just north of Yosemite, where he has instructed astronomy programs for Columbia College. He looks forward to carrying his Dobsonian telescope to where ever he can find dark skies and open space.
PETE DEVINE has taught outdoors in Yosemite for about 20 years. Originally from New England, Pete has worked in the West as a park ranger, archeologist, river guide, naturalist and teacher. He is currently Yosemite Conservancy’s resident naturalist. Pete has hiked the Alps, Andes and Himalaya, and has biked with Lance Armstrong
MOIRA DONOHUE Born and raised in Yosemite, California, was lucky to be in daily contact with grandparents who were also born and raised there in the 1880s. Their influence, and freedom to roam the woods and mountains, shaped and continue to inform her identity. Says Moira, “I paint my experience of the landscape - time, emotion, the bugs, the breeze, the colors, and me. I love being out in the elements. My hope is to convey my experience to others.” Moira earned a BFA cum laude, and an MA cum laude, were earned in 1979 from Northern Arizona University, Flagstaff Arizona, and 1990 from California State University, Fullerton respectively.
DICK EWART a veteran hiker and skier, has been a ranger-naturalist in Yosemite for over thirty years. He has hiked most of the park’s 800 miles of trails. His BA degree in biology is from the University of New Hampshire and his New England accent is as strong as ever. Dick spends his summers presenting naturalist programs at Glacier Point, and his winters leading snowshoe hikes at the Badger Pass Ski Area.
ROBERT HANNA a descendent of John Muir, lives in the Sacramento area but has been coming to Yosemite his whole life. After starting his career in financial services, Robert now has a new outdoor clothing company (Range of Light) and spends more time on environmental causes. He’s inherited his ancestor’s love for being outdoors in the Sierra and his passion for sharing the stewardship crusade.
FRANK HELLING a retired educator who taught in the Fresno, Madera and foothills outside Yosemite. He’s been a seasonal ranger at Grant Grove in Kings Canyon National Park for many years. Frank delights his audiences of park visitors, school groups and conference groups with his charming impersonation of John Muir.
CHRISTINE WHITE LOBERG has lived and worked in Yosemite for many years and has devoted herself to a photographic exploration of the park. She attended Cal State Fullerton and the Brooks Institute of Photography in Santa Barbara. She’s worked as a photographer for The Ansel Adams Gallery and has had her work published in books, calendars, magazines, etc. The thousands of Yosemite visitors she’s met in her years as an interpretive ranger will attest to her great enthusiasm for the park.
DAVID LUKAS is a popular and well-versed naturalist leader who has been leading programs in the Sierra Nevada and writing natural history books for over 20 years. He is the author of the revised guidebook Sierra Nevada Natural History and the new Sierra Nevada Birds, and has written or contributed to 40 other books. David lives in Groveland and leads many hikes in Yosemite
JOE MEDLEY is a graduate student at UC Davis, where he is continuing his raptor biology studies. Joe grew up just outside Yosemite, spent years exploring its trails and committed the past several seasons to observing great grey owls in and adjacent to the park. Joe’s father Steve was the president of Yosemite Association for 20 years and Joe continues a deep family attachment to the park
MIKE OSBORNE recently retired after a 30 year career as a ranger in Yosemite, including eight seasons as a wilderness ranger. Mike has actively photographed nature for over thirty-five years. His images have been used in promotional programs and literature supporting the Yosemite Fund and the Yosemite Association. He is also the author of the book Granite, Water & Light, an interpretive and photographic paean to the waterfalls of Yosemite Valley. His most recent book is Yosemite Conservancy’s First Light.
LUCY PARKER is a descendant of the Yosemite Indians, and great-granddaughter of Lucy Tom Telles. Brought up in Yosemite in a traditional cradle basket, Lucy worked in the park as an Indian cultural demonstrator for many summers. She has also performed living history at Bodie State Park, and demonstrated traditions of the Paiute people at the Lee Vining Visitor Center.
KEN ROCKWELL is a talented photographer as well as the creator of his own well-known web site which contains an amazing and constantly evolving compendium of thoughtful and thought provoking essays, photography galleries, Photoshop lessons and detailed test reports of new and vintage camera equipment. Ken has an artistic eye, he is engineer by training, and he enjoys sharing both his encyclopedic knowledge and forthright opinions about photography. Having fully the embraced digital age, Ken is equally adept with traditional 35mm, panoramic, medium and large format photography
MICHAEL ELSOHN ROSS has worked for Yosemite Conservancy since 1977, teaching outdoor adventure classes and leading custom adventures. He is the award-winning author of 42 books for young people including Baby Bear Isn't Hungry, the Happy Camper Handbook, The World of Small, and Snug as a Bug. He also teaches children’s book writing workshops and is popular speaker at schools and conferences around the world. Michael is passionate about showing off Yosemite’s diversity to newcomers, as well as longtime Yosemite enthusiasts. He lives with his family at the park boundary in a home overlooking the Merced River.
JOHN SENSER is a landscape and wildlife photographer/writer whom has also worked in the Sierra as an archeologist and naturalist. His image work has appeared in Arizona Highways, The Sierra Club Calendars, National Geographic’s Special Publications and his writing has appeared regularly in Central Sierra Seasons Magazine. A photographic educator for forty years, he has conducted many courses and workshops for the University of California, Columbia College, and numerous other organizations. As owner of Yosemite Light Photography (located in the mountains just north of Yosemite) he produces finely crafted photographic prints and note-cards that are sold at art shows and galleries around the state.
GUS SMITH has worked in Yosemite National Park as the Fire Ecologist for the last three years. Prior to working in Yosemite, he was an associate professor of Biology and Natural Resources at Northland College in northern Wisconsin for ten years. Gus developed a research interest and passion for wildland fire while working in the pine barrens of Wisconsin. Gus enjoys hiking in the Sierra forests and foothills and identifying the patterns that fires have left for us to discover. Sequoia trees are a favorite.
SHIRLEY SPENCER is the author/illustrator of the Conservancy’s “Flowering Shrubs of the Sierra Nevada” and co-author (with her husband Mark) of “Southern Yosemite Rockclimbing,” Shirley is also renowned as an artist, a musician/singer (yes, she has recorded a CD), an athlete and educator. Since the 1980’s thousands of people have been lucky enough to explore Yosemite with Shirley and catch her infectious affinity for the outdoors. She lives on the southern park boundary.
SARAH STOCK is a National Park Service wildlife biologist in Yosemite. In this role she works with songbirds, amphibians, bats and more. Before moving to Yosemite Valley four years ago Sarah worked on field biology programs in several parts of the US, including Alaska, the Marianas and Hawaii. She oversaw the songbird monitoring programs of the Big Sur Ornithology Lab immediately prior to moving to Yosemite with her family.
GREG STOCK is Yosemite’s first park geologist. His doctoral research involved dating the rate of uplift of the Sierra by studying flood deposits in limestone caves. Here in Yosemite he’s done new work on our glaciers and rockfall hazards. In addition to his scientific strengths, Greg is a terrific communicator who makes Yosemite’s geology sound as fascinating as it really is.
SUZANNE SWEDO Director of W.I.L.D., has backpacked the mountains of every continent. She has led groups into the wilderness for over 26 and teaches wilderness survival and natural science for individuals, schools, universities, museum and organizations such as Yosemite Conservancy and the Sierra Club. She is the author of 10 books. She lectures and consults about backpacking, botany and survival on radio and television as well as in print
CHRIS VAN WINKLE is an award-winning California artist who has served as president of the National Watercolor Society. He was also selected as one of the “top twenty” art instructors by Watercolor Magazine. For the past 30 years, Chris has taught watercolor at Citrus College in Southern California.
CHARLES WALDMAN began painting full-time in 1999 after practicing Family Medicine in Sonora (CA) for 22 years. Chuck is mostly self-taught except for two workshops with Clyde Aspevig that were a major part of his education and got him painting on-location. This is where he does most of his work. He was selected as an Artist Member of the California Art Club, The Laguna Plein Air Painters, “The Sea-to-Shining-Sea” Exhibition and has been invited to several group shows at the Haggin Museum in Stockton (CA). Recently, a painting of his was purchased for the collection of Mrs. Joan-Irvine Smith. He shows in galleries throughout the US, attends a few plein air events, and teaches workshops. The artist paints mostly in California and the West but also makes trips to other parts of the US (Maine in July 2006) and has traveled many times to France.
KEITH WALKLET is a highly admired photographer and author, and is highly sought-after as an instructor for beginner to intermediate photographers. Keith will mix discussion of fundamental concepts of successful composition with practical instruction on how to get the most from one’s equipment. He has lived and worked in Yosemite for 14 years. Widely published, his credits include Audubon, National Geographic and Sierra Club books. The Yosemite Association published his books Yosemite: An Enduring Treasure (2001), and The Ahwahnee: Yosemite’s Grand Hotel (2004) and his newest collaboration, First Light (2009).
DAVE WYMAN created Image Quest photography tours, and has had his photographs and articles appear in Outdoor Photographer, Outside, Backpacker, Sky and Telescope, and many other publications. He has conducted photography and natural history tours in California and the American West since 1982, on behalf of the Yosemite Association, the Los Angeles and San Diego Natural History Museums, the Los Angeles Zoo, the University of Southern California and UCLA. His most recent book is Yosemite in Photographs; he is also the author and photographer of Backroads of Northern California and Backroads of Southern California.
