Bird droppings can etch the paintwork surface of your car, particularly on a sunny day - AlamyFolklore has it that being hit by a bird dropping will bring you good luck. Unless you are a car owner, it seems, as that excrement could end up landing you with a bill for hundreds or even thousands of pounds to repair damaged paintwork.You can avoid pigeon droppings from pitting your paint and gulls damaging your car’s finish. First, look at the reasons they are such bad news for your car, especially at this time of year when birds are at their most active and the warmer weather makes the effects on your paint even worse.Our first expert is from the company which makes the paint, including the crucial lacquer which protects it. Matthijs Groenewolt is head of clear-coat development at the Baden Aniline and Soda Factory Europe, one of the biggest coatings suppliers in the world, with customers including BMW, Mini, Renault, Volvo, Toyota and Lexus.How the damage is causedGroenewolt says: “Bird droppings are a complex mix of uric acid, digestive enzymes, salts, fats, undigested food particles and sometimes grit. The droppings’ acidity can react chemically with the paint’s protective clear-coat leading to softening, etching and discolouration.”AdvertisementAdvertisementThis is made worse, he says, by leaving a car parked in summer – especially if it is left for a long time: “Heat and sun accelerate chemical reactions and soften the clear-coat. Deposits left for hours or longer – particularly on a hot, sunny day – are much more likely to etch the surface.”Paul Caller, the chief executive of Hertfordshire-based car care company Autoglym, agrees that summer sun will damage the paint but argues that the reason is different: “Our research shows that the ‘etching’ is not due to the corrosive properties of bird droppings. In direct sunlight, the paint lacquer softens and expands.“Simultaneously, the heat dries and hardens the droppings on the surface. As temperatures drop at night, the lacquer cools, contracts and hardens, moulding around the bird droppings. This makes the paint appear dulled or etched compared with the undamaged areas.”Rapid responseThis means that it’s crucial to get rid of the splat before it has a chance to bake in the sun. Autoglym will happily sell you some wipes which are dedicated to the task, but a wet cloth or even a baby wipe could do the job almost as well.AdvertisementAdvertisementBut don’t be tempted to attack the paint with a scourer if it has dried as you’ll damage the paint. Instead, leave a damp cloth over the dirt for a few minutes to soften it before trying again to remove it.Wiping the droppings away with a damp cloth immediately is the best short-term solution - AlamyKeeping a pack of wet wipes in the glovebox will mean you can get rid of the droppings before they do too much damage; if you need a little extra moisture to soften them, carefully squirt the windscreen washers into a wipe and leave it over the stain for a few minutes.Scraping or picking at the debris will make the damage worse. Then remember to dispose of the wipe as it’s not something you want to find in your pocket in a week’s time.Damage controlWhat about if you’ve left it too late and you notice damage in the paint? All is not lost, says Richard Tipper of Perfection Detailing. He is considered Britain’s best car cleaner and is entrusted to polish the world’s most valuable cars.AdvertisementAdvertisementHe says: “There is a way you can fix it, but you need to go carefully. If you have got rid of the dropping but can see the clear-coat has been moulded around the deposit, you can usually get it smooth again by heating the area so the lacquer flows again and becomes flat.“If you are brave you can do it with a heat gun, but that is something I’d leave to the professionals. You could try pouring hot water on it, too, or a machine polisher will soften the coating, but be careful not to wear through thin paint.”Tipper says certain car brands are more susceptible to dropping damage: “Italian, Japanese, Korean and French cars tend to have soft paint,” he says. “That means they will be damaged easily, but do respond to treatment. The Germans are much better, especially Mercedes, which has ceramic elements in the clear-coat. British brands like Aston Martin, Rolls-Royce and Land Rover are pretty hardy, too.” He says the paint colour makes no difference, although damage will be more noticeable on darker shades than on silver or white.Prevention“The easiest way to prevent damage is to avoid your car getting hit by the birds in the first place,” says Tipper. “So avoid parking spaces under trees. It’s easier to walk a little further than to clean your car.” If the spot under a popular perch is unavoidable, a protective coating will help create an extra shield for the paint, he says.AdvertisementAdvertisement“A traditional wax is easy to apply and will help repel dirt, but you will need to top it up every few weeks or months. More modern ceramic coatings will be even more effective and last longer, but are more difficult to apply. For maximum protection you could look at a protective film, but these are expensive and need to be applied professionally. But they are still cheaper than a respray.”“I’ve been quoted more than £500 to respray the panels”Mark Welbourne lives in a leafy village just outside Hitchin, Hertfordshire; that leafiness means there are a lot of trees. And with the trees come birds – and their droppings. “I swear they wait until I’ve cleaned the car before dive-bombing it. We are not talking little splats either.”His black Audi A6 Allroad bears the scars of these droppings. “I will wipe them straight away if I notice them, but if they are on the back of the car I might not see them for days, or if I’m busy I just forget,” he says. “I sometimes look at the weather forecast and hope the rain will wash them off!”Mark Welbourne wipes droppings away as soon as he notices them, but his paintwork still suffers damage - Matt WrittleThat sort of casual approach has meant that some droppings have etched their way into the clear-coat, though, most noticeably on the bonnet and roof.AdvertisementAdvertisement“I’ve been quoted more than £500 to respray the panels, so I’ll just polish it occasionally and put it down to wear and tear.”Try full access to The Telegraph free today. Unlock their award-winning website and essential news app, plus useful tools and expert guides for your money, health and holidays.