Wind turbines should be painted purple to deter bats, scientists claim

Bats and birds are being killed by the blades of the turbines because they are attracted to the insects that are drawn to the white or light grey colour.

Scientists say that if the structures were painted a different colour it might reduce the amount of wildlife killed.

Chloe Long, a PhD student from Loughborough University, said: "Our major conclusion is that turbine paint colour could be having a significant impact on the attraction of insect species to the structure, both during the day and at night."

She added: "Bats breed very slowly so if there is a significant number killed it will have an affect on the bat population. Bats are a protected species and there should be more research done to see how we can protect them from the turbines."

Miss Long and her colleagues Dr James Flint and Dr Paul Lepper measured how a turbine's colour alters how many insects gather around it.

Most turbines are painted pure white or light grey, in a bid to make them as visually unobtrusive as possible.

The researchers measured how many insects were attracted to a range of paint colours, including pure white, light and dark grey, sky blue, red and purple.

They did so by laying out coloured cards in a random sequence next to a 13m-high three-blade wind turbine situated in a meadow near Leicestershire.

Turbines painted pure white and light grey drew the most insects bar aside from yellow.

The insects attracted included small flies, large flies, greenfly, moths and butterflies, thrips, beetles and crane flies.

The least attractive paint colour to insects was purple.

The researchers also found that the ultraviolet and infrared components of paint colour, which humans cannot see but insects can, also had a significant impact, with higher levels of both attracting more insects.

"If the solution were as simple as painting turbine structures in a different colour this could provide a cost-effective mitigation strategy," said Miss Long.

But she and her colleagues suspect that other factors play a role in attracting birds and bats to wind turbines.

As well as the turbines' colour, the heat they generate may attract insects and their predators.

Bats may also find turbines difficult to detect using echolocation.