Birds regularly evade predators as quick and conniving as snakes, hawks, raccoons and cats—so why can't they out of the way of planes? It may be because birds are not able to properly gauge the speed at which a vehicle is approaching, found a team of scientists from the U.S. Department of Agriculture, Indiana State University and Purdue University.
The researchers placed cowbirds in front of a virtual simulation of a truck driving toward them. As the truck approached, the cowbirds seemed to focus on the distance between themselves and the vehicle rather than its speed, reports Jia You at Science. They consistently took flight when the truck seemed to be about 100 feet away.
But when the truck sped up, the birds did not seem to account for the faster speeds in calculating when to take flight. This could explain why the cowbird is able to avoid its natural predators but cannot safely evade a plane. As the researchers put it:
Brown-headed cowbirds in our study usually managed to respond quickly enough to avoid virtual collisions during simulated low-speed vehicle approaches, but they were often overwhelmed by high-speed approaches.
Josh Krisch of Vocativ reports that these results are not the first to show that birds are a poor match for oncoming traffic:
The findings mesh nicely with a similar study conducted last year on turkey vultures. In that study, the researchers had no sentimental ties to their avian subjects—they drove a real pickup truck directly at birds and tried to pick them off. Those hapless vultures managed to escape the pickup only when it was traveling less than 55 mph.
Planes struck around 11,000 birds in 2013, according to the FAA. In 66 of those strikes, the aircraft involved was destroyed. Around the world, 255 people have died, and 243 aircraft have been destroyed since 1988 because of bird strikes.
Overall, there were six times as many wildlife strikes at U.S. airports in 2013 as in 1990, and 97 percent of the strikes recorded at U.S. airports in 2013 involved birds. But they weren't the only animals to be in the wrong place at the wrong time—rodents, deer and bats also caused incidents.