Saturday marks the 113th anniversary of the famous first flights in 1903 in Kitty Hawk, N.C., by Wilbur and Orville Wright. Yes, those Wrights, the brothers who designed, built and flew the first powered airplane.
The first flight with Orville as pilot covered 120 feet and lasted 12 seconds; Wilbur, on the fourth and longest flight of the day, flew 852 feet for 59 seconds. All their hard work, experimentation and innovation came together that December day as they took to the sky and forever changed the course of history. Of particular interest to me is that important design ideas came from their observations of birds in flight.
Watch a flock of gulls or geese overhead, or a northern cardinal approaching your feeders: Flight demands greater intensity of effort than any other animal locomotion. Bird researchers note a bird's heartbeat, breathing rate, metabolism, body temperature and amount of food eaten as markers of this effort. The heart of a black-capped chickadee beats about 400 times a minute when asleep but about double that when active. A bird's breathing is correspondingly rapid. All birds have a high rate of metabolism, and they have the highest body temperatures of any animal, averaging 110 degrees. One example of how large their food consumption is falls to the robin, which eats as much as 14 feet of earthworms in a day. Young crows have been known to eat more than their own weight in food per day.
Bird skeletons are very flexible, strong and light. Their feathers combine lightness with extraordinary strength, and the shape of the wing is a basic factor in flying effectiveness. All these features, plus highly developed flight muscles, streamlined bodies and tails that help them to steer and to brake, make bird flight possible.
The speed of a bird's flight varies considerably among individuals and from one species to another depending upon the circumstances. The majority of small land birds travels at speeds between 20 and 30 miles per hour; geese and ducks usually range from 40 to 60 mph; and our summer-resident chimney swifts fly 60 to 70 mph.
Jim Gilbert's Nature Notes are heard on WCCO Radio at 7:15 a.m. Sundays. His observations have been part of the Minnesota Weatherguide Environment Calendars since 1977, and he is the author of five books on nature in Minnesota. He taught and worked as a naturalist for 50 years.