A spatially explicit approach to assess the collision risk between birds and overhead power lines: A case study with the little bustard

•A collision risk index of birds with power lines is proposed, using the little bustard as a case study.•The collision risk index is based on habitat suitability and flight length at collision height.•Collision risk varied temporally and spatially throughout the yearly cycle.•Yearly collision risk model was validated by an independent mortality dataset.•Results are consistent with the collision risk index being a good predictor of power line mortality.