One thing that you notice when you spend a lot of time driving, is how often birds will dive in front of moving vehicles. They don’t seem to be doing it for any particular reason. Perhaps the avian version of extreme sports?
I’ve seen everything from the basic dive across the street, to birds waiting near a stoplight for the cars to start moving and then flying under the car and around the tires. This behavior is most common, in my observations, with sparrows, but I’ve seen other birds do it as well.
Has there been any research done on these games of Chicken? Is it teenaged birds showing off their butchitude with dangerous stunts? Is it showing off for the chicks? Is it sucidal birds just not managing to get hit?
I’d think there’d be an ornithology thesis in this.
One reason birds hang out near roads is to gather up insects that cars have killed or stunned. After a few generations of this feeding strategy, car-dodging ability in such populations should be fairly good.
I have a friend who has set up bird feeding areas in her yard. The sparrows and finches (at least the ones in her yard) really like to have cover. They’re nervous out in the open. She set up a brush pile for them to play in near their feeding bowl so that she could watch them. Before then it was snatch and fly.
So possibly the sparrows like the cover of having a car over them.
I think there is actually a Cecil Adams Straight Dope column about this, or perhaps it’s a mailbag thing. It had something to do with air currents being caused by the warm air rising up from the asphalt of the road, rather than an active attemt by a bird to swoop in front of a car.
I’ll see if I can find it, if I don’t get distracted by work.
Some of it might be that you just don’t notice the ones that swoop when you’re not there.
Some may also be predator-avoidance behaviour - can’t remember where I heard about it, but it’s apparently a fairly common reason for animal roadkills - the animal reacts in a way that would be appropriate if faced with a large animal predator, but is deadly dangerous when that predator is a car.
I used to sit in my car for lunch almost every day (poor me), and noticed that the sparrows always went to the front of the parked cars to eat the squished bugs. Never the back. As for moving vehicles, I’ve seen them dart out of the way at the last moment when feeding in the road, but never had them come after my moving vehicle. Very Hitchcockesque.