Fire favours the native bee community in a semi‐arid ecosystem

Abstract

Abstract Fire is a common and frequent disturbance in Mediterranean ecosystems, affecting the diversity and dynamics of native bee communities by modifying the distribution and availability of the resources that bees require to forage and nest. Previous studies have found changes in bee diversity depending on the time since the last fire, with increases in species diversity in the early stages postburn. Using a chronosequence of plots with different times since the last fire in the Mediterranean‐climate chaparral of Baja California, Mexico, we estimated changes in overall abundance, richness, diversity and species composition of the native bee community. Bee abundance and richness were higher at recently burned plots and gradually decreased, but Hill–Shannon and Hill–Simpson diversities did not change over the chronosequences. Nearby plots (in the same locality) of different stages were more similar in composition than distant plots (in different localities) of a similar stage, suggesting a spatial correlation. Plant species richness increased after fires. Bare soil was also greater on recently burned patches and may facilitate nesting resources. The number of bees was positively correlated to plant richness. Our results highlight the importance of fire as a natural disturbance structuring the bee community in the Mediterranean chaparral of Baja California. Furthermore, our results are relevant for future conservation plans since fire management (i.e., prescribed fires) could improve conditions for sustaining greater bee richness and abundance.