Despite popular belief, research from Autoglym has revealed that bird dropping ‘acidity’ has no effect on paintwork. Autoglym’s tests with strongly acidic, neutral and strongly alkali bird dropping substitutes highlighted negligible differences in the damage caused.

Research shows that instead the damage results from the paint lacquer contracting upon cooling and moulding to the uneven texture of the hardened deposit.

As paint lacquer warms in the summer sunshine for example, it softens and expands. At the same time the heat dries and hardens any bird droppings on the surface. Then as the paint lacquer cools it contracts, hardens and moulds around the texture of the bird dropping.

The longer the deposit remains on the bodywork and the higher the temperatures, the harder the dried deposit will be and the greater the chance for the paint lacquer to mould to it as it cools. Bird dropping damage can only be prevented by motorists remaining vigilant and removing the deposit as soon as possible.

Paul Caller, chief executive officer of Autoglym, said: “It’s a great shame when an otherwise fabulous-looking car is blighted with a tell-tale patch of dull paint.

“The only way to prevent the paint becoming noticeably tarnished is to carefully remove deposits as swiftly as possible.”