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In recent decades severe mammal declines have occurred in the vast and uncleared tropical savannas of northern Australia. Mounting evidence suggests that feral cats (Felis catus), large feral herbivores and increased frequency of high-severity fires, are all contributing to declines; however, the respective influence of each threat remains unclear. There is an urgent need to quantify the relative impacts of both ‘bottom-up’ (i.e. the depletion of resources and habitat simplification from contemporary disturbance regimes) and ‘top-down’ (i.e. increased predation pressure) factors on small mammal populations to inform where, and how, remedial conservation efforts should be targeted in northern Australia. We conducted an extensive survey of mammals across ca. 370,000 km² of monsoonal northern Australia using both camera-trapping and live-trapping methods. From multispecies occupancy models, we found that …