The Marana Rotary Club meeting focused on welcoming new member Kristina Brewer as an official Rotarian and featuring a presentation by nature photographer Steve Thompson, MD.
Assistant Governor Alita Wiener conducted the induction ceremony, explaining Rotary's history and principles before welcoming Kristina as the newest member. Kristina is the principal of Roadrunner Elementary school.
Mike introduced guest speaker Steven Thompson, a Tucson-based nature photographer and retired academic endocrinologist, highlighting his work in capturing the beauty of the Sonoran Desert through his photographs.
Steve Thompson then delivered an engaging presentation about the Saguaro Forest, showcasing his nature photography of desert plants, animals, and the intricate relationships between bighorn sheep, saguaro cacti, and hummingbirds. He demonstrated his specialized photography techniques using macro and telephoto lenses to capture detailed images of desert wildlife, explaining how these species interact and the unique characteristics of the Sonoran Desert ecosystem. After the presentation, Mike proposed that Steve consider offering his photography services to the Marana Unified School District for educational purposes, which Steve welcomed.
Summary
Desert Photography and Saguaro Cacti
Steven presented as a nature photographer and discussed his equipment, including macro and telephoto lenses used to capture detailed images of desert plants and animals in the Saguaro Forest near Tucson. He explained the unique characteristics of saguaro cacti, including their water storage abilities and night-time photosynthesis process. Steven shared examples of his photography, including images of desert animals like rattlesnakes and honeybees, demonstrating how his specialized equipment allows him to capture detailed shots from a safe distance.
Desert Bighorn Sheep Identification
Steven discussed the behavior and characteristics of desert bighorn sheep, including their mating habits and how to determine a ram's age by examining hormone-related ridges on their horns. He explained the process of photographing and identifying bighorn sheep in the Sonoran Desert using high-resolution cameras and binoculars, demonstrating how to spot and count the sheep in various photos.
Saguaro Cactus Growth Process
Steven explained the growth process of saguaro cacti, noting that they grow from the top and produce approximately 100 aerials annually. He described the protective white cap on new growth and highlighted key features of cactus flowers, including multi-lobe stigma and stamens, explaining that cactus flowers are self-incompatible, requiring cross-pollination.
Saguaro Cacti Pollination Process
Steven discussed the pollination process of saguaro cacti, highlighting the role of native pollinators such as bees, white-winged doves, and hummingbirds like the Broad-tailed Hummingbird. He explained how these pollinators help transfer pollen between cacti, contributing to genetic diversity. Steven also mentioned the ocotillo plant and its relationship with hummingbirds, noting that ocotillos are self-incompatible and rely on pollinators for cross-pollination.
Hummingbird-Saguaro Mutualism Photography
Steven presented photographs and discussed the mutualistic relationship between hummingbirds and saguaro cacti, explaining how hummingbirds collect nectar while transferring pollen. He shared techniques for wildlife photography, including waiting patiently for the right moment and using backlit conditions to enhance images. Steven also showed photos of other wildlife, including cardinals and a desert lizard basking on rocks.
Steven presented a detailed explanation of how hummingbirds display color through structural features rather than pigments, demonstrating with photographs how the birds can control light reflection to show different colors depending on their orientation. He discussed his photography techniques using fast shutter speeds and specialized equipment to capture hummingbirds and other wildlife in natural settings.