Do euglossine males (Apidae, Euglossini) leave tropical rainforest to collect fragrances in sugarcane monocultures?

Abstract

Euglossine bees are known to be long-distance pollinators in tropical rainforests. But there is controversy concerning to the flight ranges of these bees between forest fragments. In an isolated fragment of Atlantic Rainforest in Pernambuco, NE Brazil, surrounded by sugarcane monocultures, it was examined if euglossine males leave closed rainforest to collect fragrances. In a straight-line transect leading from forest into a sugarcane plantation, euglossine males were simultaneously captured by scent baits at seven distinct points: inside the forest, forest edge, outside the forest in the sugarcane fields at distances of 10 m, 50 m, 100 m, 250 m and 500 m from the forest edge. A total of 945 euglossine bees of 16 species were recorded. The results demonstrate different relations of the Euglossini species to the closed forest. Males of 11 species did not leave the forest. Such species, together with the plants they are linked to, seem to be the most threatened by habitat fragmentation. Only bees of five species were found at the scent baits in the sugarcane fields. Already the 10 m sampling point outside the forest showed a drastic reduction in species richness, indicating that the forest edge functions as a barrier for most euglossine species.

Is the “Centro de Endemismo Pernambuco” a biodiversity hotspot for orchid bees?

“…Whatever the reasons, the fact is that El. felipei was never recorded outside ESEC Murici in any previous field study in the "Centro de Endemismo Pernambuco" (Bezerra and Martins, 2001;Martins and Souza, 2005;Milet-Pinheiro and Schlindwein, 2005;Darrault et al, 2006;Farias et al, 2007Farias et al, , 2008Moura and Schlindwein, 2009; this study). If it is true, we hypothesise that a high level of endogamy may be present in this species, one additional factor, besides (and most probably a consequence of) its restricted geographic distribution, to threaten this species.…”

“…Areas in northeastern Brazil, particularly at the northern margin of the São Francisco river, are a good example. Only a few areas have been effectively sampled in Paraíba (Bezerra and Martins, 2001;Farias et al, 2007;Farias et al, 2008), Pernambuco (Milet-Pinheiro and Schlindwein, 2005;Darrault et al, 2006), and Alagoas (Darrault et al, 2006;Moura and Schlindwein, 2009;Nemésio 2010b). Almost nothing is known from the states of Ceará, Sergipe and Rio Grande do Norte, although a new orchid bee has recently been described from Ceará (Nemésio and Ferrari, 2012).…”

The orchid bee fauna (Hymenoptera, Apidae) of a core area of the Cerrado, Brazil: the role of riparian forests as corridors for forest-associated bees

“…Their males were shown to be able to fly 500 m out of forest fragments into a sugarcane matrix to get aromatic compounds (Milet-Pinheiro & Schlindwein 2005) and to cross urban areas (Raw 1989) and pastures (Tonhasca Junior et al 2003) between forested areas. E. securigera is also able to cross pastures (Tonhasca Junior et al 2003) and was considered as "common in the forest edge" by Nemésio & Silveira (2006a) what is supported by data from Tonhasca Junior et al (2002) and Milet-Pinheiro & Schlindwein (2005).…”

Orchid bees: a new assessment on the rarity of diploid males in populations of this group of Neotropical pollinators

“…Apart from reductions in the abundance of orchid bees in forest fragments of reduced size, studies have shown that some species may have stronger dispersal limitations in fragmented landscapes, and the type of matrix may also affect the dispersal of some species of the group differently (Powell and Powell 1987;Milet-Pinheiro and Schlindwein 2005).…”