A study recorded the frequency that birds left their mark on cars in five cities around the UK, and found crimson motors were targeted the most.

Green cars were found to suffer least, followed by silver, while white vehicles escaped more often than black in the analysis of 1,140 cars in Brighton, Glasgow, Leeds, Manchester and Bristol over two consecutive days, to see whether colour made a difference to birds.

During the study, drivers were also asked how quickly they removed droppings from their cars.
Only 17 per cent, one in six, said they wiped off deposits immediately when they saw them, 20 per cent said they took action “within a couple of days” while 55 per cent waited until the next car wash.
The remaining 8% never washed their cars or left it to others to organise.

As well as being unsightly, insurance industry figures show bird droppings on vehicles can be an expensive problem and estimate the damage caused by bird-poop-stained paintwork costs motorists £57m a year in unnecessary repairs.

Halfords car cleaning expert David Howells said: “This research does have a serious side because the problem annoys drivers, causes damaged paintwork and affects the value of vehicles. To protect your body work from damage, droppings should be carefully cleaned off as soon.”

Theories abound on motoring and social networking websites as to why birds are attracted to pooping on some cars more than others.
– A Lexus driver reckoned newly polished cars suffer because birds see a reflection of themselves.
– A Ford Focus owner agreed and said the darker the colour the deeper the reflection and the more violent the reaction.
– An Alfa Romeo owner said it depends where you park and a Mercedes driver said blue was the worst as it reminded birds of water.

Others thought birds saw red as a danger or birds went for similar colours to their own plumage, such as in seaside resorts seagulls went for white cars, while in cities pigeons go for grey.

The Halfords study found little difference between cities and the seaside in the colours that specific species of birds apparently aim for.

Researchers who compiled the results found 18% of red cars were marked with droppings, blue 14%, black 11%, white 7%, grey/silver 3%, green 1%.

Leading car polish experts Autoglym said the damage to vehicle paintwork arose not from the acid or alkali in bird faeces, but from paint lacquer softening and expanding to form an uneven mould around the dropping which produced a dull patch.

Grainier textures from seed eating birds produced more the most blemishes, so pigeons are worse for motorists than seagulls.

Autoglym says that birddropping damage can only be prevented by owners removing the poop as soon as possible.

The British Trust for Ornithology were more circumspect on the role of colour in the “drop zone” for birds. ““We do know that birds can be attracted to certain colours during display but it (droppings on cars) is probably more to do with where you park; if you park where birds roost then you are going to get more droppings on your vehicle,” said a spokesman.