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Disturbances are drivers of ecosystem function and play important roles in shaping ecological communities. Pre- scribed fire and grazing disturbances are common management tools in restored and remnant grasslands. The effects of these management actions on plant communities and on vegetation-dwelling invertebrates are generally well studied. However, less is known about their effects on ground-dwelling invertebrates, which can contribute to important ecosystem processes like herbivory, predation, and decomposition. We examined bison grazing and prescribed fire effects on abundance, diversity, and community composition of ground-dwelling invertebrate groups in restored tallgrass prairies using pitfall trap samples. Surprisingly, invertebrate Shannon diversity decreased when bison were present and was unaffected by fire or the fire–bison interaction. Bison, and to a lesser extent fire, also shifted community composition, increasing abundance of ground, rove, and dung beetles, as well as orthopterans and spiders. Prescribed fire generally increased beetles but caused declines in sev- eral ecologically diverse invertebrate groups, including harvestmen and true bugs, although these reduced abundances did not lead to differences in overall diversity. Bison presence may amplify the abundances of dominant groups, such as ground and dung beetles and orthopterans, that outcompete other invertebrates and reduce diversity. Implications for insect conservation Prescribed fire and grazing by bison change ground-dwelling invertebrate community composition, but bison presence did not reduce the abundance of most taxonomic groups. Fire may have short-term negative impacts on some invertebrate groups that promote desirable invertebrate-driven ecosystem processes, but these effects are likely short-lived, and the resulting environmental mosaic under bison and fire management could support biodiversity over the long-term. 

Restoring vegetation in degraded ecosystems is an increasingly common practice for promoting biodiversity and ecological function, but successful implementation is hampered by an incomplete understanding of the processes that limit restoration success. By synthesizing terrestrial and aquatic studies globally (2594 experimental tests from 610 articles), we reveal substantial herbivore control of vegetation under restoration. Herbivores at restoration sites reduced vegetation abundance more strongly (by 89%, on average) than those at relatively undegraded sites and suppressed, rather than fostered, plant diversity. These effects were particularly pronounced in regions with higher temperatures and lower precipitation. Excluding targeted herbivores temporarily or introducing their predators improved restoration by magnitudes similar to or greater than those achieved by managing plant competition or facilitation. Thus, managing herbivory is a promising strategy for enhancing vegetation restoration efforts. 

Abstract Tallgrass prairie is among the most threatened ecosystems but is often fragmented and surrounded by human‐modified landscapes. Small mammals are integral components of tallgrass prairies. However, little is known about how landscape composition, configuration, and management impact small mammals in tallgrass prairies.We conducted a systematic literature review to identify species‐specific and community associations with three broad topics: landscape composition, landscape configuration, and management practices.We identified 61 studies that assessed our variables of interest. We categorised the location, species assessed, variables monitored, and results by species and for the community.The majority of studies (64%) were conducted in two states, Illinois and Kansas. Deer mice (Peromyscus maniculatus), prairie voles (Microtus ochrogaster), and white‐footed mice (Peromyscus leucopus) showed specific associations with landscape variables, with deer mice preferring bare ground and recently burned plots, and prairie voles preferring thatch and negatively associated with prescribed fire. White‐footed mice were frequently associated with wooded areas.Small mammal biodiversity was positively associated with patchy habitats containing greater diversity in vegetative composition and management regime. Management and land composition were both relatively well studied for several species; habitat configuration was understudied.We identified significant gaps in our understanding of small mammal landscape ecology in tallgrass prairies. With tallgrass prairie restoration a growing trend in this region, a greater understanding of drivers of small mammal populations will be crucial to successful restoration efforts. Future research should focus on understudied areas and species, and examine how habitat heterogeneity impacts small mammal biodiversity. 

Grazing as a management tool is often intended to alter plant community dynamics through preferential foraging. Bison diet in the western United States has been well studied, especially in short and mixed grass remnant prairies. However, there is little known about what bison consume in restored and tallgrass prairies. As bison reintroductions are used more commonly in eastern tallgrass prairies, it is important to understand their diet to predict future impacts on prairie plant communities. This study aims to understand bison diet across different seasons, and asks whether diet differs among male and female, and differently aged bison. We used stable isotope analysis to quantify δ¹³C and δ¹⁵N in plants and used a Bayesian isotope mixing model to estimate bison diet. We found bulls relied more heavily on C₄plants and wetland plants than cows, which relied more heavily on forbs, but no differences in diet between ages. Our analysis shows that bison primarily grazed on C₄grasses throughout the late spring and summer. However, bison foraged more on wetland species and forbs in the late summer and fall. This change in diet could have implications for wetland species and habitats, through dung inputs and trampling. The relatively high reliance on forbs for nearly one‐third of bison diet could mean intended impacts of reintroduced bison such as increased plant diversity through preferential grazing on grasses could be dampened. Managers reintroducing bison to restored prairie ecosystems should ensure adequate wetland and forb species, in addition to a mix of grasses. 

Abstract Ecosystem restoration is a critical component of land management, countering the loss of native biodiversity. Restoration efforts are enhanced by reintroducing naturally occurring ecosystem processes, including disturbances that may impact species characteristics such as niche position or niche size. In grasslands, grazing and fire affect plant diversity and habitat complexity, which potentially influence insect dietary behaviors and thus their contributions to functions like seed and arthropod predation. Using carbon and nitrogen stable isotopes, we characterized variation in the dietary niche of six ground beetle species (Coleoptera: Carabidae) in response to grazing by reintroduced bison and prescribed fire disturbances in twenty tallgrass prairies. Management disturbances did not affect activity density for most beetle species and mean trophic position was mostly unaffected. However, five of six species exhibited increased trophic niche area and breadth with disturbances, indicating a switch to a more generalist diet that incorporated a wider range of food items. The combination of bison and fire impacts may increase vegetation patchiness and heterogeneity, driving these diet changes. Morphological traits and microhabitat preferences might mediate response to disturbances and the resulting heterogeneity. Combining prescribed fire and grazing, which increases plant diversity and vegetation structural diversity, may help beetle communities establish over time and support the ecological functions to which these insects contribute. 

Abstract In the midst of an ongoing biodiversity crisis, much research has focused on species losses and their impacts on ecosystem functioning. The functional consequences (ecosystem response) of shifts in communities are shaped not only by changes in species richness, but also by compositional shifts that result from species losses and gains. Species differ in their contribution to ecosystem functioning, so species identity underlies the consequences of species losses and gains on ecosystem functions. Such research is critical to better predict the impact of disturbances on communities and ecosystems. We used the “Community Assembly and the Functioning of Ecosystems” (CAFE) approach, a modification of the Price equation to understand the functional consequences and relative effects of richness and composition changes in small nonvolant mammal and dung beetle communities as a result of two common disturbances in North American prairie restorations, prescribed fire and the reintroduction of large grazing mammals. Previous research in this system has shown dung beetles are critically important decomposers, while small mammals modulate much energy in prairie food webs. We found that dung beetle communities were more responsive to bison reintroduction and prescribed fires than small nonvolant mammals. Dung beetle richness increased after bison reintroduction, with higher dung beetle community biomass resulting from changes in remaining species (context‐dependent component) rather than species turnover (richness components); prescribed fire caused a minor increase in dung beetle biomass for the same reason. For small mammals, bison reintroduction reduced energy transfer through the loss of species, while prescribed fire had little impact on either small mammal richness or energy transfer. The CAFE approach demonstrates how bison reintroduction controls small nonvolant mammal communities by increasing prairie food web complexity, and increases dung beetle populations with possible benefits for soil health through dung mineralization and soil bioturbation. Prescribed fires, however, have little effect on small mammals and dung beetles, suggesting a resilience to fire. These findings illustrate the key role of re‐establishing historical disturbance regimes when restoring endangered prairie ecosystems and their ecological function. 

A primary goal of ecological restoration is to increase biodiversity in degraded ecosystems. However, the success of restoration ecology is often assessed by measuring the response of a single functional group or trophic level to restoration, without considering how restoration affects multitrophic interactions that shape biodiversity. An ecosystem-wide approach to restoration is therefore necessary to understand whether animal responses to restoration, such as changes in biodiversity, are facilitated by changes in plant communities (plant-driven effects) or disturbance and succession resulting from restoration activities (management-driven effects). Furthermore, most restoration ecology studies focus on how restoration alters taxonomic diversity, while less attention is paid to the response of functional and phylogenetic diversity in restored ecosystems. Here, we compared the strength of plant-driven and management-driven effects of restoration on four animal communities (ground beetles, dung beetles, snakes, and small mammals) in a chronosequence of restored tallgrass prairie, where sites varied in management history (prescribed fire and bison reintroduction). Our analyses indicate that management-driven effects on animal communities were six-times stronger than effects mediated through changes in plant biodiversity. Additionally, we demonstrate that restoration can simultaneously have positive and negative effects on biodiversity through different pathways, which may help reconcile variation in restoration outcomes. Furthermore, animal taxonomic and phylogenetic diversity responded differently to restoration, suggesting that restoration plans might benefit from considering multiple dimensions of animal biodiversity. We conclude that metrics of plant diversity alone may not be adequate to assess the success of restoration in reassembling functional ecosystems.