Comparative floral preferences in nectar and pollen foraging by Scaptotrigona postica (Latreille 1807) in two different biomes in São Paulo (Brazil)

Abstract

To describe the trophic resources used by Scaptotrigona postica, honey and bee bread samples were taken monthly from May 2015 to December 2016 at two different localities. Fontes do Ipiranga State Park (PEFI), an urban remnant of the Atlantic Forest, and the Mogi Guaçu Biological Reserve (RBMG), in the Cerrado. Two colonies were kept in each site. Samples were analysed with the melissopalynological method in order to calculate the relative frequencies. Principal component analysis was used to compare the similarity between the samples and to examine the influence of quantitative and qualitative data on the ordination of the pollen types. Similarity tests were performed to compare the pollen spectra of the bee bread and honey samples between the study sites and seasons. Hence, 69 and 61 pollen types were identified in 33 honey and 29 bee bread samples. The main families in honey were Asteraceae, Euphorbiaceae and Fabaceae; in bee bread Fabaceae, Myrtaceae and Sapindaceae were the main families for both localities, followed by Asteraceae, Euphorbiaceae and Solanaceae at the RBMG. The results showed that the species maintains its floral preferences regardless of the biome in which it occurs. Also, demonstrates that the bees make use of nectariferous and polliniferous sources available in the preserved areas as well as in its surroundings. There is a risk of pesticides exposure caused by the use of trophic resources of cultivated plants by this bee. This points to the need for further studies.