Apex predators can suppress smaller bodied “mesopredators.” In doing so, they can provide refuge to species preyed upon by mesopredators, which is particularly important in regions where mesopredators are invasive. While most studies of mesopredator suppression focus on the response of mesopredators to human control of apex predators, other factors—including natural and anthropogenic disturbance—also drive the occurrence of apex predators and, in doing so, might shape spatial patterns of mesopredator suppression. We examined the role of fire in shaping the occurrence of an apex predator and, by extension, mesopredators and small mammals in a fire‐prone region of semiarid Australia. We measured the activity of an apex predator (the dingo Canis dingo); an invasive mesopredator it is known to suppress (the red fox Vulpes vulpes); and two species of native small mammal (Mitchell's hopping mouse Notomys mitchelli; silky mouse Pseudomys apodemoides) that are potential prey, across 21 fire mosaics (each 12.56 km2). We used piecewise structural equation modelling and scenario analysis to explore the interactions between fire, predators and prey. We found that dingoes were affected by fire history at the landscape scale, showing a preference for recently burned areas. While foxes were not directly affected by fire history, a negative association between dingoes and foxes meant that fire had an indirect impact on foxes, mediated through dingoes. Despite the suppression of foxes by dingoes, we did not observe a trophic cascade as small mammals were not negatively associated with foxes or positively associated with dingoes. Synthesis and applications. Disturbance regimes have the capacity to shape patterns of mesopredator suppression when they alter the distributions of apex predators. Environmental change that promotes native predators can therefore help suppress mesopredators—a common conservation objective in regions with invasive mesopredators. The indirect consequences of disturbance regimes should be considered when managing disturbance (e.g. fire) for biodiversity conservation.

Identifying factors that affect species' distributions in highly modified landscapes, especially threatened species, is a key issue for conservation worldwide. Three types of factors commonly are considered important: the extent and pattern of suitable habitat at a landscape scale; the availability of key resources at a local scale; and interactions with other species. The brush-tailed phascogale (Phascogale tapoatafa) has undergone range contractions and regional extinctions in Australia and falls within the critical weight range of mammal species with high risk of decline. Yet, in some regions, it persists despite marked habitat loss and disturbance. We investigated the distribution of the brush-tailed phascogale in a highly modified region in central Victoria where it is a 'flagship' for community conservation. At 50 sites, stratified geographically and in relation to topography and surrounding forest cover, we carried out surveys using remotely sensed cameras (in parallel with nest box inspections). We used an occupancy modelling framework and information-theoretic approach to analyse factors influencing detectability and occupancy. The brush-tailed phascogale was widespread, recorded at 84% (42/50) of sites. The environmental space occupied by sites with camera records matched that of nest boxes containing established nests of this species. Detection probability was influenced by survey effort and site-level measures of habitat quality (logs, litter, topographic position) likely reflecting population abundance. Dry forested slopes were favoured compared with gullies. The study area, with its dry forests of rough-barked eucalypts, is a stronghold for this species. The broad distribution of the brush-tailed phascogale in this highly modified region can be attributed to retention of ~36% regional forest cover and a relatively high level of structural and functional connectivity. In such modified landscapes, complementary actions by land managers to sustain remaining large tracts of forest and also a mosaic of wooded vegetation across the rural landscape will help such species to persist.

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Context. Landscape management and restoration in rural environments is frequently driven by community groups, who often use 'flagship' species to generate broader engagement. In southeastern Australia, installation of nest boxes for hollow-dependent fauna is undertaken by many groups. Monitoring the outcomes of such projects offers opportunities for citizen science. Aims. The aim of the present study was to report on a community-led project to install and monitor nest boxes to enhance the conservation of a threatened species, the brush-tailed phascogale (Phascogale tapoatafa), and to investigate the extent of nest box use, factors influencing use, changes in use through time, and the effectiveness of nest boxes as a monitoring tool. Methods. A community group installed 450 nest boxes across 150 sites to monitor and provide habitat for the brush-tailed phascogale. Of these, 102 sites were stratified in relation to:(1) geographic sub-region; (2) forest patch size; and (3) topographic position. Nest boxes were inspected five times over 8 years. We modelled factors influencing nest box use at the tree, site, and landscape level. We compared nest box data with data from camera traps at 50 sites to assess their value as a monitoring tool. Key results. In any given survey, up to 6% of nest boxes had individuals present and up to 22% had evidence of use by the brush-tailed phascogale. There was greater use of nest boxes when installed on 'stringybark' type trees than 'box' and 'gum-barked' species. Nest box use was greater for sites on forest slopes than in gullies, and use varied between years. Surveys using remote cameras were more effective at detecting phascogales than monitoring nest boxes. Conclusions. Nest box monitoring can provide insights into the distribution and habitat requirements of hollow-dependent species, and engage the community in citizen science. Elements that enhance community-led monitoring include scientific input to project design, collecting data in a consistent manner, allocating sufficient time for data curation, engaging people invested in project outcomes, maintaining good relationships with stakeholders, and sharing data for analysis. Implications. Collaboration between scientists and community groups can be of benefit to both parties. However, to maximise scientific and conservation outcomes there must be effective engagement and adequate resourcing for project coordination.