The number of seabirds killed by colliding with wind turbines could be reduced by painting black and white stripes on the blades and poles, say researchers.
at the University of Birmingham, UK, and at Natural England, a public body that has a say in planning applications for offshore wind farms in England, wanted to devise a pattern that could be easily painted on to offshore turbines to reduce their impact on bird life.
Between 140,000 and 328,000 , according to one estimate. It is harder to estimate how many marine birds are killed by offshore turbines each year, says Martin, as the birds fall into the ocean.
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Wind turbines have typically been painted all white to look less conspicuous to humans, but this doesn鈥檛 take into account a bird鈥檚 vision, says Martin.
A previous study, published in 2020, looked at the effect of on four onshore turbines in Norway. Bird collisions were reduced by 70 per cent compared with white turbines nearby.
But Martin believes that further improvements could have an even greater impact.
Based on an analysis of previous studies into bird vision and bird collisions with wind turbines, Martin and Banks came up with a series of guiding principles to aid their design of a turbine that would harm fewer birds.
鈥淢ost birds do not see too much fine detail in their vision 鈥� especially compared to humans,鈥� says Martin, so any design shouldn鈥檛 be too complex.
Many collisions occur in low light, he says, so the design should be easy to decipher in the dark, while high internal contrast would help the turbine stand out against different backgrounds, such as a cloudy or sunny sky.
In low levels of light, black and white patterns are best, says Martin. 鈥淚n the dark, a red and white pattern would rapidly look like shades of grey,鈥� he says. Black and white stripes create a flickering pattern when the blades spin that studies suggest .
The design hasn鈥檛 yet been tested, but Martin hopes that manufacturers will consider it, particularly as it would be easy and cheap to implement. The US, the UK and other countries are planning massive expansions of wind farms at sea, so it is a good time to produce new designs, he says. 鈥淚 think people are starting to take the issue seriously now.鈥�
鈥淭his is very interesting research,鈥� says at the University of Glasgow, UK. Seabirds have few young and are slow to mature, so additional deaths of adults might be unsustainable for their populations, he says.
Global Ecology and Conservation
