ATBC 2012
49th Annual Meeting Bonito-MS, Brasil
S22.P.04
Exotic bee is one of the most generalist bee species on Brazilian bee-plant
interaction networks
Giannini TC1, Imperatriz-Fonseca V L1, Saraiva A M2, Kleinert AMP1 - 1Universidade
de São Paulo - Ecologia, 2Universidade de São Paulo - Sistemas Digitais
Determining bee and plant interactions has an important role in understanding the
general biology of bee species, as well as the potential pollinating relationship between
them. Bee surveys have been conducted in Brazil since the end of the 1960s. Most of
them applied standardized methods and identified the plant species where the bees were
collected. In plant-pollinator interactions, species are commonly seen as generalists
when they interact with many species of different taxa, and specialists if they interact
with one or a few closely related species. It has already been demonstrated that in
pollination systems the most generalized species are usually network keystone species.
Since they interact with most plant species, they play an important role to maintain the
whole network. To analyze the most generalist bees in 47 Brazilian bee surveys, we
built a matrix of bee-plant interactions. The most generalist bees were estimated by
determining the three bee species of each surveyed locality that presented the highest
number of interactions. Surveys were conducted in urban areas, Tropical Dry Forest
(Brazilian Caatinga), Tropical Shrublands (Brazilian Cerrado), and in Tropical Moist
Forest (Brazilian Atlantic Forest) biomes. We found 39 species of bees, most of them
belonging to Apidae (31 species) and Halictidae (6) families, and to Meliponini (14)
and Xylocopini (6) tribes. On most surveys Apis mellifera and/or Trigona spinipes were
the most interacting species. Considering the first and second species with the highest
number of interactions, Apis mellifera was present on 75% of the Brazilian surveys and
Trigona spinipes, on 64%. Apis mellifera is an exotic bee species and Trigona spinipes,
a native species. Both are widespread and present broad diet breadth, high number of
individuals per colony and an aggressive foraging behavior, which are probably the
most important features to explain these results.
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