Paint it black: How researchers reduced bird kill at a wind farm

Norwegian researchers may have found a simple method for keeping birds from flying into wind turbines.

Roel May's team from the Norwegian Institute for Nature Research painted one of three blades on the turbines black.

May's team reviewed a number of ways that have been suggested to reduce bird kill at wind turbines before getting started, and ranked them in terms of which ones were the most promising in light of what is known about bird behaviour, and in terms of how easy they would be to implement.

The theory is painting one blade black would minimize what is known as motion smear on the fast moving blades. The tip of a blade can be travelling up to 250 km/h.

"That means they become blurred," said May.

"For our eyes, we can't follow the tip anymore. It's going too fast. Birds have the same problem."

Researchers painted black blades on four of 68 turbines at a coastal wind farm in Norway. They compared bird mortality for the seven and a half years before the turbines were painted with three and a half years after, as well as mortality at neighbouring turbines.

They found a 70 per cent reduction.

More research

There is interest in the Netherlands and South Africa to replicate the study, which will be important, said May, because it is yet to be determined if it will work in different environments with different bird species.

It is not known how many birds are killed by wind farms on P.E.I.

The P.E.I. Energy Corporation only has reports for its own wind farms. It said recent studies of the 10 turbines at Hermanville/Clearsprings in eastern P.E.I. estimate 13.5 mortalities per year.

More from CBC P.E.I.