We built it; did they come? Pollinator diversity and community structure in a post-mining prairie restoration project

Authors: BENEDUCI, ZACHARY - Auburn University; SWAB, REBECCA - Ohio University; Scott, Drew; BYRD, SHANA - Dawes Arboretum

Submitted to: Ecological Restoration
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/17/2023
Publication Date: 12/1/2023
Citation: Beneduci, Z.J., Swab, R.M., Scott, D.A., Byrd, S. 2023. We built it; did they come? Pollinator diversity and community structure in a post-mining prairie restoration project. Ecological Restoration. 41(4),180-188. https://www.muse.jhu.edu/article/911492.

Interpretive Summary: Bees and butterflies (pollinators) are disappearing in the United States. This disappearance is partly due to habitat loss. Coal mining contributes to habitat loss and has affected millions of acres in Appalachia. Laws require coal companies to reclaim the surface of old mines. Part of this requirement involves planting plants to reduce soil loss. Companies typically choose non-native plants. However, they could plant cost-effective native prairie plants. This would both reduce soil loss and supply food (pollen and nectar) for pollinators. Thus, this study aimed to assess if coal mines with prairie plants could attract greater numbers and types of pollinators compared to mines with weedy plants. Similar numbers of pollinator species occurred in native and non-native plantings. However a few uncommon pollinators were only observed in native plantings. Additionally, pollinator diversity increased with the number of flowering plants observed. Therefore, planting more species of plants that bloom across the season on coal mines should help attract pollinators. We also found five species of uncommon bees feeding on the flowers of prairie plants. The presence of these five species of bees shows promise in our prairie seed mix to help at-risk pollinators. Our findings (1) suggest that land managers could plant hundreds of thousands of acres of coal mines with prairie plants to help pollinators and (2) native plants can support uncommon pollinator species.

Technical Abstract: More than 2.5 million hectares have been impacted by coal mining in the Appalachian region of the United States. Revegetation to forested cover is a desirable post-mining land use but is often impractical given the challenges of reforestation on abandoned coal mines. Considering a prospective pollination crisis and the potential value of habitat restoration for pollinators, prairie restoration on mine lands offers a practical restoration option. We tested the effect of native prairie restoration in comparison to traditional reclamation with non-native cool-season grassland on pollinator richness, diversity, and community structure at three mined sites in southeastern Ohio. Rather than treatment level effects, we found correlations between overall floral and pollinator richness (F1, 28.75 = 10.44, P = 0.003), floral richness and pollinator Shannon’s diversity (F1, 29.43 = 5.33, P = 0.028), and floral beta diversity and pollinator beta diversity (Mantel: r = 0.24, P = 0.001). Additionally, pollinator community structure varied by month (constrained PCoA; P = 0.001). A few uncommon pollinator species (Andrena helianthi, Megachile inimica, Bombus auricomus, Bombus perplexus, and Bombus vagans) were only present in native treatments. Therefore, judicious design of prairie restoration seed mixes could increase floral diversity and provide across-season forage for pollinators in post-mining landscapes. Our findings also suggest, by the presence of several specialist/uncommon pollinators, that prairie restorations on coal mines can provide habitat for at-risk pollinators.