Invasive rodents are a major contributor to global biodiversity loss.They also interact with other introduced species in invaded ecosystems,so managing rodent impacts is complex because ecological relationships are often incompletely understood.These knowledge gaps also undermine our ability to predict global change effects (such as climate and land-use change) on invaded ecosystems when potential changes in extrinsic environmental factors are uncertain.We quantified the ecological role of mice in grassland/shrubland ecosystems in New Zealand,in combination with (a) other invasive mammals (herbivores and top predators) , (b) climate change,and (c) habitat modification.Mice are mesopredators in this ecosystem.We found that a combination of (1) trophic interactions among invasive mammals, (2) altered frequency of pulsed seeding events (masts) in grasslands, (3) seral transitions to a shrub-dominated plant community,and (4) proximity to expanding intensive pastoralism all operated synergistically to alter the dynamics of mice.These findings imply serious adverse impacts of global change on rodent impacts,and are all key processes to consider when managing rodents in invaded ecosystems.