Spatio-temporal variation in populations and communities: plant-bee-parasite interactions in the Monte desert

Figure 1. The Monte desert and the approximate location of the nine study localities (red circles). Map modified from Roig et al. (2009, J. Arid Env. 73: 164-172).

We are studying solitary bee ecology and plant-bee-parasite networks throughout 2000 km in Argentina’s Monte desert. The overarching goal of the project is to gain understanding of the determinants of the spatio-temporal variation in populations and communities.

Thanks to funding from FONCYT (project code PICT-2018-1272) we have established a consortium of researchers based at institutions located strategically throughout the distribution of the Monte desert. In late August and early September 2021 (the Austral late winter-early spring) we have established a network of replicated experiments in nine localities throughout the Monte desert, from its northernmost limit in Salta to the southernmost distribution in Chubut (Fig. 1).

We are using a standardized, replicated experimental design based on trap nests for solitary bees (Fig. 2), from which we can study population demography of wood-nesting solitary bees and their interspecific interactions, namely bee interactions with plants (from analysis of nest pollen) and nest parasites, which will allow us to construct plant-bee and bee-parasite interaction networks. We expect to generate data on solitary bee demography (fecundity, survival and abundance) and on the structure of mutualistic (plant-bee) and antagonistic (bee-parasite) networks. Our standardized experimental approach will allow us to revisit several outstanding hypotheses concerning the geographic and temporal variation of populations and communities. We hope that our project will allow us to shade light on long-standing open questions in population and community ecology.

Figure 2. Nests of some bee species recorded in Monte desert sites in Villavicencio Nature Reserve, Mendoza. a, Megachile leucografa visiting a flower of Larrea divaricata. b, Detail of brood cells of Megachile leucografa with petals of Larrea sp. c, Nest of Megachile leucografa with brood cells built with petals of Larrea sp. d, Nest of Anthidium sp. built with hairs of fruits of unidentified plant species. e, Nest of Trichothurgus laticeps, with pollen mostly of Opuntia sulphurea. f, Nest of Xylocopa atamisquensis, with seven brood cells at different stages of development, from larva (left) to pupa (center) to adult (right). Source: Vázquez et al. (2012 Ecology 93: 719-725).

Project team