is the total number of prey categories (Krebs, 1999). We obtained the proportions under the “averaged” method as it reduced the bias of individuals that eat a large number of items (Zaccarelli, Bolnick, and Mancinelli, 2013). We excluded plant material in all the above analyses as it was not convenient to estimate N and %N. However, we re-estimated the %W to consider the plant content, then determined the type of diet according to the %W of plant material using the scale of Espinoza et al., (2004): Insectivorous (0-10%), Omnivorous (11-50%), herbivorous (51-100%). Using data obtained from the pitfall traps, we determined the effective number of species (Jost, 2006) for both areas, and the relative abundance of each prey category; the latter was considered a measure of prey availability in the forests. Then, we estimated the selection ratios considering each prey category as a food resource and the %N as a measure of use. In addition, we determined the standardised Manly’s selection ratio with a type I design (Manly et al., 2002). To test for statistical differences in the diet of the two populations, we applied a Permutational Multivariate Analysis of Variance (Permanova) using a Bray-Curtis dissimilarity (Anderson, 2001), and a square root data transformation. As a Permanovaassumes similar multivariate distribution (Anderson, 2001), we tested the multivariate homogeneity of group dispersions using the “betadisper” function from the“vegan” R package version 2.5-5 (Oksanen et al., 2013). Finally, we used non-metric multidimensional scaling (Zuur, Ieno, and Smith, 2007) to order and represent the prey categories consumed by L. etheridgei in each Polylepis forest. We complemented the above analysis with a Pianka overlap index: