Habitat corridors, which act as a bridge between disconnected habitats, have been shown to promote species richness and help conserve native species in fragmented landscapes. Communities of plants and animals are known to also be affected by other aspects of fragmented habitats, including habitat shape and edge-area ratio. However, few studies have examined how communities respond to these habitat factors in terms of life history traits such as size and nesting strategy. To address this, we used a set of replicated experimental landscapes to study how habitat connectivity and shape affected the abundance and life history traits of a functionally important group, wild bees. To examine bee communities, we used pantraps to collect specimens at habitat edge and center positions within habitat fragments, which differed in terms of their shape and connectivity to other habitat patches. We then determined abundance by counting all collected specimens, and measured bee functional traits including body size, nesting type, sociality, parasitism, and resource specialization.
Results/Conclusions
Results show that connectivity has a significant effect on abundance, with unconnected patches having a greater abundance of bees (X2=9.03, p=0.003), contrary to other studies on arthropods and connectivity. Position within the patch (X2=0.001, p=0.97), and patch shape (X2=2.77, p=0.1), however, did not have a significant effect on bee abundance. Average IT spans were not significantly impacted by connectivity (X2=2, p=0.16), position (X2=0.03, p=0.86), or patch shape (X2=0.95, p=0.33). Sociality was not significantly impacted by connectivity (X2=0.07, p=0.8), position (X2=2.71, p=0.1), or patch shape (X2=0.51, p=0.77). Nesting habitat was not significantly impacted by connectivity (X2=0.74, p=0.39), position (X2=0.9, p=0.34), or patch shape (X2=1.29, p=0.52). Based on our results, we conclude that spatial aspects of a fragmented landscape, such as connectivity, may affect bee abundance, but the bee community response to spatial factors is not driven by traits.