When settling down for a bite to eat, wild starlings like a little privacy—and they're smart enough to know when they've got it. A recent study shows that wild starlings won't touch their food if a human is looking at it, but don't mind so much when a human is close but averting his ravenous, predatorial gaze.
Most animals respond to obvious signs of endangerment—a screaming child running around with his arms flailing, say—but this is the first time scientists have shown a bird to be sensitive to eye direction. (Most wild animal lovers, however, know that you can sneak up to the critters by sidestepping towards them and looking out of your periphery).
This perception may be crucial for starlings, who tend to flock in dense packs. All these friends are useful when they want to attack predators and take down trees (video), but when a backyard bird-feeder is spotted at lunch time, those "friends" become competition. So the earlier an individual starling figures out that a food source is safe, the more time he or she gets to gorge before the rest of the crew joins. So birders, show a little respect as you stare at your avian friends—or at least be discreet about it.