Stingless bees (Apidae: Meliponini) at risk in western Mexico

Abstract

The current global pollinator crisis highlights the need to investigate the diversity and distribution of ecologically and socially relevant taxa such as tropical stingless bees. We analyzed the diversity and composition of stingless bee (Meliponini) communities at a regional scale in west-central Mexico using an extensive direct search along an altitudinal gradient encompassing different climate and vegetation types. Our hypothesis was that meliponine bee diversity would be greater in tropical warmer. We found a total of 14 meliponine bee species, including two new records for the region. We identified three types of bee assemblages: one in hot lowland climates with tropical dry forest vegetation, one in temperate highland climates with mixed oak-pine forest vegetation, and one in the warm ecotone with mixed subdeciduous forest vegetation between the hot and temperate zones. As expected, the lowland assemblage in the tropical dry forest vegetation had the greatest diversity (11 species). In the warm ecotone, meliponine species from temperate highlands and hot lowland habitats converged; this region should therefore be considered a high conservation priority area. Fifty percent of the meliponine bees found are endemic and have a very low incidence, suggesting that their populations may be endangered. Given the extensive and ongoing change of land use to avocado plantations in the warm ecotone and temperate highlands with mixed oak-pine forest vegetation cover, specific conservation plans should be generated to conserve the natural ecosystems and this important native pollinator group. Abstract in Spanish is available with online material.