Spatial design of the study sites, consisting in four 8 m × 20 m plots in the corners of a 100 m × 200 m rectangle, and two transects of 50 m × 2 m in the middle.
Trap nests arranged in the field. Trap nests consist of wood pieces with a longitudinal hole of three different diameter where bee species nest. Each occupied trap nest constitutes one bee nest.
Models evaluating the effect of flower diversity and other ecological factors on the reproductive variables of different bee species of the 14 study sites. a) Complete model. b) Nested models generated by removing variables with non-significant effects or small path coefficients that were non-significant. Model 2 was selected by ∆AIC for all bee species.
Box-plot summarizing the path coefficients of model 1 (see Fig. S3) for the seven bee species studied here. Model 1 describes the effect of flower diversity (estimated using flower richness), flower abundance (estimated using flower density) and temporal stability of flower production along the flowering season (estimated as the inverse of coefficient of variation of the weekly flower abundance mean), fire (estimated as time elapsed since last fire), and elevation (estimated as meters above the sea). Y axis represents the path coefficients that rank from 1 to -1, and the x axis represents the effect of above mentioned ecological variables on three bee reproductive variables: A is the average brood cell number per nest per site, B is the total number of brood cells per site, and C is the total number of nests per site. In blue color are the ninety-five percent confidence limits of path coefficients obtained from bootstrap sampling of the distribution of path coefficients.