Wild bee community change over a 26‐year chronosequence of restored tallgrass prairie

Abstract

Restoration efforts often focus on plants, but additionally require the establishment and long‐term persistence of diverse groups of nontarget organisms, such as bees, for important ecosystem functions and meeting restoration goals. We investigated long‐term patterns in the response of bees to habitat restoration by sampling bee communities along a 26‐year chronosequence of restored tallgrass prairie in north‐central Illinois, U.S.A. Specifically, we examined how bee communities changed over time since restoration in terms of (1) abundance and richness, (2) community composition, and (3) the two components of beta diversity, one‐to‐one species replacement, and changes in species richness. Bee abundance and raw richness increased with restoration age from the low level of the pre‐restoration (agricultural) sites to the target level of the remnant prairie within the first 2–3 years after restoration, and these high levels were maintained throughout the entire restoration chronosequence. Bee community composition of the youngest restored sites differed from that of prairie remnants, but 5–7 years post‐restoration the community composition of restored prairie converged with that of remnants. Landscape context, particularly nearby wooded land, was found to affect abundance, rarefied richness, and community composition. Partitioning overall beta diversity between sites into species replacement and richness effects revealed that the main driver of community change over time was the gradual accumulation of species, rather than one‐to‐one species replacement. At the spatial and temporal scales we studied, we conclude that prairie restoration efforts targeting plants also successfully restore bee communities.

Restoration increases bee abundance and richness but not pollination in remnant and post‐agricultural woodlands

“…In many cases, pollinators recover quickly after restoration of degraded ecosystems (Fiedler , Hanula and Horn , b, Williams , Griffin et al. ). However, plant–pollinator networks in restored ecosystems are sometimes less complex than in natural communities (Forup et al.…”

“…Restoration activities may help to remediate the impacts of agricultural land use on pollinators and pollination. In many cases, pollinators recover quickly after restoration of degraded ecosystems (Fiedler 2010, Hanula and Horn 2011a, b, Williams 2011, Griffin et al 2017. However, plant-pollinator networks in restored ecosystems are sometimes less complex than in natural communities (Forup et al 2008, Williams 2011, suggesting that pollination function may not recover completely.…”

Bee community responses to a gradient of oak savanna restoration practices

“…Our study took place during the initial phases of a long-term restoration project. We speculate that over time our restoration treatments will continue to acquire greater distinctiveness of both biotic (Pindar 2013;Griffin et al 2017) and abiotic conditions, and through continued increases of bee richness, abundance, and functional diversity observed in managed treatments, such changes could translate to increased pollination function as well.…”

“…Pollinators are a ubiquitous, speciose, and functionally important group in both agricultural and natural systems. Although a great deal is known about the role of habitat management for bees in agricultural landscapes (Isaacs et al ; Klein et al ; Kennedy et al ; Blaauw & Isaacs ), far less is known about the impact of ecosystem restoration on bee communities (Dixon ; Griffin et al ). Nonetheless, healthy plant communities are of primary importance in natural ecosystem function, and pollinators have the ability to regulate the largely insect‐pollinated forbs in natural communities (Benadi et al ).…”

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

“…The reconstructed prairies also varied in age, suggesting that flower visitors respond relatively quickly to prairie reconstruction. This has recently been demonstrated for bee communities on reconstructed prairies in Illinois, U.S.A. (Griffin et al 2017). However, it is unclear whether these findings are applicable to other ecosystems, as there are substantial geographic differences in the diversity and specialization of plant-pollinator interactions (Johnson & Steiner 2000).…”