Karen Krebbs worked at the Arizona-Sonora Desert Museum for more than 26 years and has extensive knowledge of birds, mammals, plants, reptiles, insects, deserts, and animal adaptations and behavior. Her passion for hummingbirds has resulted in a book, book chapters, scientific papers, and also a husbandry manual for captive hummingbirds for the Association of Zoos and Aquariums. Her research on hummingbirds includes migration, nesting biology, behavior, song development, and longevity. Karen regularly advises zoological institutions and aviaries on the proper care and husbandry of captive hummingbirds. She has conducted educational workshops and seminars on Sonoran Desert animals and plants for various organizations, schools, yearly wildlife festivals, and local conservation groups.

Karen has also studied bats for more than 30 years; she presents lectures, leads workshops, and trains government employees on the proper handling and protocol for studying bats. She has led and co-led natural history trips in Arizona, New Mexico, Texas, Mexico, Baja, Costa Rica, Ecuador, Galapagos, and Africa. Karen, an avid hiker, camper, photographer, and natural history traveler, has a B.Sc. degree in Wildlife & Fisheries Science from the University of Arizona. She has lived in Tucson, Arizona, for more than 50 years.