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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. 

Restoration outcomes are notoriously difficult to predict and often fall short of restoration goals. Post‐restoration management actions may help overcome barriers to successful establishment, such as dispersal limitations and competition. Layering these management actions to increase the intensity of disturbances may improve restoration outcomes, but they also can be expensive and laborious, depending on the intensity or number of actions implemented. We investigated a series of disturbance intensities on previously restored tallgrass prairies using a randomized block design. Combinations of seeding, harrowing (low intensity disturbance), disking (high intensity disturbance), and herbicide were implemented after a prescribed burn. After 11–14 years, we measured percent cover of all species present to determine long‐term effectiveness. We found that the high intensity disturbance treatment increased native species richness by over 40% and native species Shannon diversity by 15% when compared to control plots. Overall diversity and composition of the plots varied among sites that were treated in different years, indicating that seed mix composition and site conditions were still likely important determinants of community outcomes. Regardless, the consistency of the high intensity management actions to increase site richness and diversity after more than a decade may allow managers to achieve restoration goals, even if later management is limited, justifying the time and resources to enhance existing restorations.