What is the aim of the review?
To systematically collate and synthesise published and unpublished evidence in order to examine the impacts of wind turbines on bird abundance. To achieve this, four questions were addressed:

• 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?