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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 C₄ plants 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 C₄ grasses 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.

Given that 29% of seabird species are threatened with extinction, protecting seabird colonies on offshore islands is a global conservation priority. Seabirds are vulnerable to non-native predator invasions, which reduce or eliminate colonies. Accordingly, conservation efforts have focused on predator eradication. However, affected populations are often left to passively recover following eradications. Although seabirds are highly mobile, their life history traits such as philopatry can limit passive recolonization of newly predator-free habitat. In such cases, seabird colonies can potentially be re-instated with active restoration via chick translocations or social attraction methods, which can be risky and expensive. We used biogeographic and species-specific behavioral data in the Hauraki Gulf, New Zealand, a global hotspot of seabird diversity and predator eradications, to illustrate the use of geographic information systems multi-criteria decision analysis to prioritize islands for active seabird restoration. We identified nine islands with low observed passive recovery of seabirds posteradication over a 50-year timeframe, and classified these as sites where active seabird management could be prioritized. Such spatially explicit tools are flexible, allowing for managers to choose case-specific criteria such as time, funding, and goals constrained for their conservation needs. Furthermore, this flexibility can also be applied to threatened species management by customizing the decision criteria for individual species' capacity to passively recolonize islands. On islands with complex restoration challenges, decision tools that help island restoration practitioners decide whether active seabird management should be paired with eradication can optimize restoration outcomes and ecosystem recovery.