Value of open areas to preserve euglossine bees in slash-and-burn agriculture landscapes of the Mayan forest

Given the ongoing global pollinator crisis, understanding how land-use change affects pollinator insects, such as euglossine bees, has never been more important. This information can be used to promote biodiversity conservation and sustain food production in agricultural landscapes, such as those exposed to slash-and-burn agriculture (SBA) – a traditional farming system that is expanding worldwide. As SBA creates heterogeneous landscape mosaics of different land uses, we used a site-landscape design to assess the relative importance of four dominant land uses (old-growth forest, secondary forest, burned land, and agricultural land) and two landscape structure variables (old-growth forest cover and land-use diversity) for preserving euglossine assemblages in the Mayan forest, Mexico. We captured bees in 20 sites (5 sites/land-use type) and estimated bee abundance and species richness in each site. Contrary to our hypothesis, bee abundance was between 2x and 3x higher in open areas (burned and agricultural lands) than in old-growth and secondary forests, and increased in more deforested landscapes. However, bee abundance was not related to land-use diversity, and species richness was independent of land-use type and landscape structure variables. These findings indicate that open areas contribute to the preservation of euglossine bees in SBA landscapes of the Mayan forest. However, this contribution is likely related to the maintenance of high forest cover in the region, where open areas are still small and close to the forest – optimal landscape scenarios for forest species, especially for euglossine bees, which are highly mobile and can find many supplementary resources in open areas.