We used to teach students about the silent flight of owls by swinging blocks of wood. The blocks were attached to a rope; one was covered in carpeting and one was not. As we swung the blocks in a fast circle, lasso-style, students could easily hear the plain block whoosh by, but the carpeted block was silent. The differing blocks demonstrated the purpose of a special feathery fringe that covers the leading edge of an owl’s wing. According to KQED Science, “When birds flap their wings, it creates turbulences in the air as it rushes over their wings. In general, the larger a bird is and the faster it flies, the larger the turbulence created and that means more sound.” But the owl’s fringed wing breaks the wind and reduces the turbulence. Here’s a close-up of that fringed edge:
This amazing BBC Earth video comparing the sound and turbulence of owl, falcon, and pigeon flight provides a perfect visual demonstration of this concept:
Researchers at the University of Cambridge have been delving deeper into owl’s silent flight to determine if that same ingenuity could be used to reduce sound created by airplane engine fan blades or wind turbines. The researchers discovered that owl wings not only make use of a fringed leading edge, but also downy flight feathers, and a porous, elastic fringe at the training edge. Scientists are now looking to replicate these characteristics in a 3D-printed plastic coating that would be applied to industrial fan blades. “According to the researchers, a significant reduction in the noise generated by a wind turbine could allow them to be spun faster without any additional noise, which for an average-sized wind farm, could mean several additional megawatts worth of electricity.” Yay nature! Find out more here.
Did you know…
Lists of Wisconsin owls vary but after a bit of cross referencing my favorite source, The Cornell Lab of Ornithology’s All About Birds, with Wikipedia and the Wisconsin Department of Natural Resources, I think it’s safe to say Wisconsin owls include the following:
Recorded in Wisconsin but not commonly:
If you’re interested in attracting owls to your yard, Cornell’s NestWatch website offers a great “All About Birdhouses” section. It includes nest box plan downloads, known nesting period, best nest box placement, and helpful tips like this one for the barred owl that suggests 3-4 inches of wood chips be placed in the bottom of the nest box.
To Do This Month:
Try this owl call quiz from the Larry Meiller Show. Do you recognize the call of the the long-eared owl, eastern screech owl, barred owl, northern saw-whet owl, and the great-horned owl? Listen to the end to check your answers.
Discover why Leopold found sandhill cranes so majestic – learn about their biology and history from renowned bird expert Dr. Stanley Temple, then see them up close in Leopold Country! Attend one of the six Crane Congregations at the Aldo Leopold Foundation during the month of November.
Take a guided Night Walk at the UW Arboretum for the Deer Running Moon on November 18th, 6:30-8pm. Hear night sounds and consider what may have inspired the Ho-Chunk to give the November full moon this name (others call it the Frost Moon). Free, no registration required.
Celebrate #GivingTuesday with a talk by top-selling rural-life Author Jerry Apps at the Aldo Leopold Nature Center on November 28th, 7-9pm. Listen to him share stories and excerpts from his books and rural-life experiences.
Join the Young Professionals Group, PACK, for Brew Lights at Henry Vilas Zoo, November 29th 6-9pm. Sip on bubbles of beer under the sparkle of lights at the 2nd annual beer tasting! Grab some holiday cheer and help toast Zoo Lights and the holiday season!
Check out the Nature Net Calendar of Events for more fun family programs.
Teachers looking to up your bird game, look no further. Flying Wild, which is developed by the Council for Environmental Education with funding from the National Fish & Wildlife Foundation, is “designed to inspire young people to discover more about the natural world… [and] get involved in activities that promote environmental learning and stewardship. The Flying WILD program places special emphasis on reaching urban schools with student populations that traditionally receive few opportunities to participate in environmental education initiatives.”
Teachers across the country are invited to attend Flying Wild training sessions to learn about the curriculum, along with information about migratory birds, their conservation needs, and ideas for community engaging activities such as school bird festivals. In Wisconsin, these training efforts are led by the Wisconsin Society for Ornithology and the Wisconsin Bird Conservation Initiative, with staff support from the Wisconsin Center for Environmental Education.
Natural Resources Foundation Field Trips
My son loves owls. He’s nine. He loves them enough that being woken during predawn light to listen to the owls calling in our backyard does not make him grumpy. He knows their calls and does a pretty spot-on “who cooks for you” barred owl impersonation. So, when his grandparents saw an opportunity in the Natural Resources Foundation of Wisconsin field trip listing to take part in banding and re-releasing saw-whet owls at the Linwood Springs Research Station, we had to go. Linwood Spring Research station staff and interns use a mist net to capture about 700 owls each year during the fall migratory season. The night we visited was too rainy to witness the mist nets, but my son got a major bucket list item checked off when he was allowed to hold an adorable saw-whet owl, Wisconsin’s smallest owl.
The Natural Resources Foundation hosts field trips of all varieties throughout the year. They offer “unique opportunities for all ages and abilities to explore and learn about bats, birds, butterflies, beetles, and more.” Trips are led by professionals from the Department of Natural Resources and other experts, including some at Nature Net member sites. The trips are sorted by activity level and many are denoted as family friendly. Upcoming trips include “Winter Tree ID” and “North Country Nordic Adventure.” Fees do apply and a membership to the Natural Resources Foundation is required but in our case, this bucket-list-worthy experience was well worth it. And we’ll also now receive updates on our banned owl when it shows up in another mist net along its migratory path to Tennessee or Georgia.