Fig. 2. Performance of the HSI model for Capercaillie at the level of sample plots. Capercaillie habitat preference, as expressed by Ivlev´s electivity index, increased across the 10 intervals of summer habitat suitability. Ivlev´s index and the mean HSI scores per interval were closely correlated (weighted least square linear regression; Pearson´s R²). N values (no. sample plots per interval) are given below the x-axis.