Why Bird Poop Is White

  Birds brighten our lives. They connect us with nature. But sometimes they connect us a bit too directly with nature. Park under the wrong tree - where a flock of starlings or grackles comes to roost - and nature may cover your car so thickly that it takes a trip or two through the carwash just to see through the windshield again. And why is most of the bird poop we see white? The answer is that birds, unlike mammals, don't produce urine. Instead they excrete nitrogenous wastes in the form of uric acid, which emerges as a white paste. Owners of red cars, look out! A study in England found that red cars are most likely to be the target of bird droppings!