BBU have helped take this field forward through collaboration with Dr Robin Colyn in his modelling of Flight and Collision Risks to better inform developers where turbines will have the least impact for birds.
From 22 operational wind farms in South Africa:
-
An average of ~4.6 bird fatalities occur per turbine per year;
-
At one Eastern Cape wind farm ~1 raptor per month is killed by turbines;
-
15% of these are Red Data species;
-
Many of these fatalities could be avoided.
Green solutions to reduce fatalities include:
-
Placing farms well away from hot-spots of activity;
-
Placing (3-km) buffers around nests to keep turbines well away;
-
Surveying new areas using specialists to ensure no Red Data species occur within the boundaries;
-
Shut down turbines at critical (migration) times;
-
Paint a blade black to increase visibility to eagles;
-
For vultures: reduce animal carcasses on site, and attract birds away with vulture restaurants [new!];
-
For associated power lines, stagger the pylons to reduce bustard collisions [new!].
Success of black-blade mitigation in Norway
White-tailed eagle deaths on the small island of Smøla have been reduced to zero over a 6-year period by the introduction of black blades. One blade per turbine, on 4 turbines, were painted black and compared with white blade turbines nearby (Stokke et al, 2017, B. Iuell pers comm).
Their results showed that the black blades killed no more eagles, whilst the white blades continued to kill eagles at an average of 6 birds per year.
We hope to introduce this innovative and clever mitigation to various wind farms in Africa to reduce the high rate of raptor deaths.
Video: Arild Magnus Soleim (Smøla wind farm manager)