Wind energy is the fastest growing energy technology in the world, with a yearly growth rate estimated at 30%, reflecting policy commitments in many countries to renewable energy in order to meet greenhouse gas emission targets. Wind energy is seen as a key element of the shift to sustainable energy supplies; however, despite the clean image of wind energy, there is some evidence that wind farm developments may have potentially deleterious environmental impacts. Attention has been brought to the possible impacts on bird populations caused by displacement and direct 'bird strikes'. Here we systematically review the impact of wind turbines on bird population abundance.
The objective has been to assess the evidence on the positive and negative effects of wind turbines on bird abundance. To achieve this four questions were identified:
- Do wind turbines affect bird abundance?
- Are some bird taxon more vulnerable than others?
- Does the number or power of turbines in a windfarm installation have an impact on the effect of windfarms on bird abundance?
- Can any other ecological factors or windfarm characteristics be identified which have an impact on the effect of windfarms on bird abundance?