Native bees and Apis mellifera share their food sources in Pampean agroecosystems.

CILLA, G., FERNÁNDEZ CORUJO V. , MARRERO H.J., CHAMER M & MEDAN D.

CABA

Conferencia; Apimondia; 2011

We investigated the flower visitation patterns of bees in the Inner Pampa of Argentina (Carlos Casares and General Villegas districts, Buenos Aires province) to know (a) if the honeybee Apis mellifera shares its food sources with Pampean native bees, and (b) which is the share of native plants and exotic plants in the diets of the honeybee and the native bees. We surveyed fields under current agricultural use (including low-resource scenarios and high-resource scenarios) and fields where agriculture has been abandoned for periods varying between one and 25+ years. In all scenarios, Apis mellifera shared a mixed native-exotic diet with native bees belonging to several taxonomic families. The assemblage of plants used by native bees varied in composition among families. Time after abandonment of agriculture was positively associated with diversity of native bees and negatively associated with honeybee abundance. However, native bees may be more frequent pollinators than the honybee in particular agricultural scenarios (sunflower fields).