Seasonal Variation in Bee-Plant Interactions in an Inselberg in the Atlantic Forest in Southeastern Brazil

Abstract

Studies on bee-plant interactions are relevant to the understanding of temporal patterns in neotropical communities. In isolated habitats such as inselbergs little is yet known about the temporal dynamics in the availability of fl oral resources and interacting bee. In the present study, the objective is to verify the eff ect of seasonality on the bee-plant interaction in an Atlantic Forest inselberg in southeastern Brazil. The bees were sampled monthly in the dry (April/2008-September/2008) and wet seasons (October/2008-March/2009) using an entomological net. A total of 322 bees of 33 species were captured on fl owers of 34 species of plants during the year. Bees richness was similar between seasons (22 species in the wet season and 21 in the dry season), but abundance was higher in the wet season (60% of individuals) and higher diversity occurred in the dry season. Augochloropsis sp1 were the most abundant species and visited the largest number of plant species at each season. In the interaction network, plants with the highest degree were distinct between the seasons. The number of possible interactions was higher in the dry season compared to the wet season and connectance was similar; nestedness however varied between the seasons. The composition of plant and bees species was distinct between the seasons, as well as the interactions between them, mainly due to the alteration in the composition of the plant species and the change in the choice of the bees for the floral resources between the seasons.

Bee-Plant Interaction Networks in a Seasonal Dry Tropical Forest of the Colombian Caribbean

“…We corroborated what similar studies have found; network properties remain quite constant through time (Alarcón et al 2008, Olesen et al 2008, Petanidou et al 2008, Marques et al 2018. Low connectance is an excepted property of pollination networks (Jordano 1987), and obtained networks had a low connectance, being lower in dry season; this season had a higher species richness and connectance has a negative relation with this value (Jordano et al 2009).…”

“…In ecosystems with high seasonality, it has been found differences in connectance, modularity, and niche overlap, having dry season networks more connected and less modular and with a higher niche overlap (Santos et al 2014). Studies involving bee-plant interactions in these kinds of ecosystems have reported differences in nestedness between seasons, besides a higher diversity of the bee community in dry season (Marques et al 2018). Seasonal dry tropical forests (SDTFs) are representative ecosystems characterized by a high seasonality, alternating long dry periods with rainy months (Murphy & Lugo 1986).…”

Recover and They’ll Come: Flower Visiting Bees Benefit from the Continuous of Micro-Environments Set by Regenerating Forest Fragments

“…As old forests are being increasingly reduced to fragmented landscapes (Alaux et al, 2017;Boscolo et al, 2017;Jauker et al, 2019;Sobreiro et al, 2019), the expected effect is the decline of the diversity of plants and pollinators (Aguiar et al, 2018;Marques et al, 2018;Sobreiro et al, 2019). However, we can interpret here that occurrence of bees in different micro-environments is possibly facilitating the flow of pollen between plants at different sites, and this seems to mitigate the impacts of forest reduction on the responses of plant-flower visitors.…”

“…Additionally, some studies investigated the foraging networks of bees and found that some species forage habitats with different landscapes to satisfy their specific feeding and nesting needs (Viana et al, 2012;Sobreiro et al, 2019;Boscolo et al, 2017). Since in highly connected landscapes, the accessibility of bees to different (micro) environments appears to be higher (Hass et al, 2018;Boscolo et al, 2017;Kratschmer et al, 2018;Marques et al, 2018). Here we can consider that in a continuous matrix of micro-environments, the bees in search of floral resources would be more dispersed in the mosaic, looking for the flowers with the greatest amount of resources and therefore the richness and abundance of local bees would be less, as suggested by Boscolo et al (2017).…”

“…However, the effects of environmental changes on local landscapes cannot be excluded. In this regard, recent studies have shown that the landscapes that surround the forest matrix can influence the composition and distribution of bees (Marques et al, 2018;Rollin et al, 2019;Sobreiro et al, 2019), due to the permeability of these pollinating insects can be affected by the functional connectivity and heterogeneity of the landscape (Boscolo et al, 2017). Therefore, understanding the potential effects of local environmental changes on the diversity of bees can help to promote conservation strategies and improve the survival chances of these insects.…”