Cascading Effects of Reintroducing Long-Extirpated Herbivores
A major objective of our research group is to evaluate the population, community and ecosystem-level consequences of reintroducing once-extirpated tule elk (Cervus canadensis nannodes) into coastal landscapes in northern California. We are using a large-scale 20-year-old exclosure experiment stratified across three habitat types to investigate how this landscape-level restoration action has affected
1) the dynamics of key plant invaders (Ender, Christian & Cushman 2017), 2) the assembly and composition of plant communities (Johnson & Cushman 2007; Lee, Spasojevic & Cushman, in preparation), 3) the dynamics of small-mammal populations (Ellis & Cushman 2018), 4) the composition of ground-dwelling arthropod communities (Cecil, Spasojevic & Cushman 2019), and 5) nutrient cycling and soil characteristics (Dodge, Eviner & Cushman, in preparation). Returning once-extirpated megafauna back to their native ranges is a much-needed conservation action, but it needs to be done with detailed knowledge of the extended consequences of such landscape-level manipulations, and may come with a wide range of unintended and sometimes undesirable consequences.