Its a body paint damage waiting to happen, within minutes.
Do you have a friend who seems to be so freakishly obsessed about his car that a single bird shit on his car summons him to the nearest water source so that he can wipe it off as soon as he can? And when he gets multiple bird shots on the hood and roof he swears like one angry chewbacca from star wars.
Well, he's no freak. He just knows how damaging bird shit is. Its plain acid man. And it leaves etching mark on the paint as soon as it gets pass the clear coat. I'm sure you've seen puzzling hairline cracks on your car paint surface. That's probably caused by bird shit. Sometimes fruits and leaves decomposing on the paint and coating surface also cause the same damage.
Avoid further damage by always having a bottle of water and some disposable paper towels in the car. I keep a roll of toilet paper in the glove box coz thats what they are for; shit wipes, either straight from the hole or on the hood. If you've got cash to spare, get a quick detailer spray or quick wipes for your car from car detailing product outlets or major hardware retail store like ace harware or fix-it.
Try not to bake any bird shit cookies on your hood, or any where on your car.