Bradley Blackwell of Wildlife Services explains that the most effective avoidance technique may not come from the ground, but from the air. If airplanes were better lit, birds would see them and avoid them.
Most bird-aircraft collisions occur within the airport environment. Two-thirds of bird strikes that result in serious aircraft damage occur between zero and 500 feet above ground level. But a substantial number of strikes occur between 501 and 3,500 above ground level. At that height, certain ground-level dispersal methods, like loud noises or bird-chasing dogs, are ineffective. So it seems appropriate to look for a way to lessen strikes when an aircraft is at a higher altitude.
I think one method could involve pulsing lights that make aircraft more visible to birds. The idea for this comes from more than a decade of anecdotal information that is graduating from theory to field research and practice.
It goes back to 1999, when I was contacted by Precise Flight of Bend, Oregon. They told me that they had an FAA-approved pulsing light system for planes that was being used to enhance pilot-to-pilot and pilot-to-ground visibility. But, bush pilots in the Pacific Northwest and Alaska noticed that the pulsing lights also seemed to reduce bird strikes.
The company asked if we had any information to support this. I dug through the scientific literature and saw that there were some indications it could be true. For example, vision is a primary sensory pathway in birds. While birds, like humans, see in color, they have different photoreceptors and can see beyond the range of humans. Also, different species see differently. It seemed reasonable to begin conducting some experiments. So I partnered with my National Wildlife Resource Center colleagues, Thomas Seamans and Glen Bernhardt, and later with engineering expert Scott Philiben of Precise Flight and Dr. Esteban Fernandez-Juricic of Purdue University.
In our first experiment, we set up a large cage at the end of a one-mile lane, and placed live birds inside. We built a pseudo wing with landing lights on top of a truck and then drove it toward the bird-filled cage at a speed of 75-miles-per hour. The idea was that the experiment would mimic a small aircraft, such as a Cessna, taking off while birds were feeding on the ground alongside the runway. We also drove a truck without lights toward the birds. And in all cases, we filmed the experiments.
We learned a lot from the experiment and continue to refine it. Our latest work uses three, high-speed cameras that are able to film down to 1/10th of a second. We also tested different pulse frequencies and different approach speeds, all while measuring behavior and speed of response, as well as ambient light conditions and lighting treatments. Last year, we were invited to present some of our data to Boeing. The results of our study will be published later this spring in the journal Animal Behaviour. study Our findings are promising. We are optimistic that our research will result in methods to help birds detect and avoid aircraft in the air. This will add another tool in the wildlife hazard mitigation toolbox and complement existing wildlife management on airports and new technology, such as radar. Radar is a great tool, but it's not the only solution, especially at airports with heavy traffic where aircraft deviation isn't always practical.
So, approaching the problem from a variety of perspectives and utilizing the best-available technology can reduce bird strikes, reduce damage and save lives.
Bradley Blackwell is a Research Wildlife Biologist with the U.S. Department of Agriculture. He works out of the National Wildlife Research Center's Ohio Field Station and specializes in reducing wildlife hazards to aviation. The views expressed are the author's alone and do not represent the official position of the Discovery Channel. For comments, please email firstname.lastname@example.org.