Flower visitor communities are similar on remnant and reconstructed tallgrass prairies despite forb community differences

Abstract

One common goal of habitat restoration and reconstruction is to reinstate the biodiversity found at intact reference sites. However, few researchers have examined whether these practices reinstate communities of flower‐visiting insects. This is unfortunate, as anthropogenically mediated declines in flower visitors, including bees (the primary pollinators for most terrestrial ecosystems), beetles, flies, and butterflies, have been reported worldwide. Biodiversity declines may be especially severe in North America's tallgrass prairie, a once‐vast grassland that has experienced severe destruction and degradation due to agricultural conversion. As such, we assessed the structure of forb and flower‐visiting insect communities as a whole and two subsets of the flower visitor community—bees and phytophagous beetles—across five tallgrass prairie remnants and five reconstructed prairies (former crop fields) in Kansas from 2013 to 2015. Remnant prairies had significantly higher forb diversity and differed significantly in forb composition, compared to reconstructed prairies. Despite the dissimilarities in forb community structure, there were no differences in flower visitor diversity or abundance between remnants and reconstructed prairies. However, when considered separately, bee communities exhibited significantly greater variability in composition on reconstructed prairies, likely due to the abundance of generalist bee species visiting non‐native legumes at two reconstructed prairies. Our work provides evidence that prairie habitat reconstruction is a valuable tool for reestablishing flower‐visiting insect communities and also emphasizes the considerable role that non‐native species may play in structuring grassland plant–bee interactions.

Differences in bee community composition between restored and remnant prairies are more strongly linked to forb community differences than landscape differences

“…(c) Bee community composition differed between restored and remnant prairies (p = 0.01), with NMDS representing community dissimilarity in multivariate space. NMDS was calculated in three dimensions but only the first two were plotted for simplicity of work supporting the concept that β-diversity and composition are important metrics for understanding diversity in conservation (Denning & Foster, 2018a;Griffin et al, 2017;Haley, 2018;Purvis et al, 2020;Tonietto et al, 2017).…”

Wild bees of Grand Staircase-Escalante National Monument: richness, abundance, and spatio-temporal beta-diversity

“…Previous investigations into the interaction of bees and flowering resources show contradictory responses of bees to the presence and abundance of flowering plants ( Denning & Foster, 2017 ; Potts et al, 2003 ; Tepedino & Stanton, 1981 ). For example, remnant prairies and reconstructed prairies in Kansas differed in the composition and abundance of flowering plants ( Denning & Foster, 2017 ) but showed no significant difference in richness or abundance of bees. In contrast, Tepedino & Stanton (1981) found constant and significant positive correlations between floral richness and bee richness at prairie sites in Wyoming.…”

Establishing forbs for pollinators in agricultural landscapes of the Great Plains, U.S.A.

“…Returning forbs to agricultural landscapes holds promise for maintaining pollinators (Haaland et al 2011; Ricigliano et al 2019; Baden‐Böhm et al 2022). Unfortunately, establishing the abundant, species‐rich stands of forbs necessary to support diverse pollinator communities has proven challenging (Dötterl & Vereecken 2010; Blaauw & Isaacs 2014; Denning & Foster 2017; Ouvrard et al 2018; Arathi et al 2019; Nichols et al 2019; Rivest & Forrest 2019; Vandever et al 2021; Baden‐Böhm et al 2022; Simanonok et al 2022). This study identified practical avenues for increasing numbers and abundances of forb species.…”