Invasive Predator Management in Australian Ecosystems

Australia’s unique biodiversity has been profoundly altered by introduced mammalian predators such as feral cats and red foxes, which drive local extinctions of ground-nesting birds, small mammals and reptiles. Management approaches have evolved from broad-scale lethal control—principally baiting with sodium fluoroacetate or 1080—to integrated strategies that combine predator surveillance, habitat modifications and novel technologies. Understanding the ecological consequences of predator suppression, including mesopredator release and compensatory immigration, has led to adaptive protocols that address non-target impacts and behavioural shifts among surviving individuals. Landscape-scale interventions, underpinned by robust monitoring via camera traps and occupancy modelling, now inform targeted baiting schedules and spatially explicit control campaigns. Moreover, innovations such as toxin-delivering implants in threatened species and exclusion fencing offer complementary tools to mitigate unwanted casualties. Effective programmes emphasise cross-tenure coordination, community engagement and continuous evaluation to refine methods, minimise ethical concerns and safeguard non-target fauna. Insights from Australian ecosystems provide a framework for invasive predator management worldwide, demonstrating the importance of multi-faceted, evidence-based interventions.

Research from Nature Portfolio

Recent experiments employing aerial baiting of feral cats with Eradicat across Western Australia demonstrated significant year-on-year declines in site occupancy as measured by camera traps and occupancy modelling. These results confirm the efficacy of broad-scale, toxin-based removal when maintained over multiple seasons and highlight the value of repeated landscape-level monitoring for adaptive timing and distribution of baits. Complementary investigations into red fox habitat selection revealed that individual foxes regularly exploit human-altered habitats—such as forest–farmland interfaces, roads and reservoirs—and display long-distance nocturnal commutes. These findings indicate that control efforts must target not only forest interiors but also anthropogenic edges and resource subsidies that sustain invasive populations. Coordinated control across land tenures, combined with restriction of anthropogenic food sources, emerges as critical for reducing predation pressure on native fauna.

Invasive Predator Management in Australian Ecosystems publication trend

The graph below shows the total number of articles in invasive predator management in australian ecosystems across all publications each year (not limited to Nature Index journals).

Technical terms

Mesopredator release: Population increase of subordinate predators following suppression of a top predator, often leading to amplified impacts on prey.

Landscape-scale baiting: A control method deploying toxic baits over extensive areas to reduce invasive predator density across broad habitats.

Occupancy model: A statistical framework used to estimate species presence and site use from detection–non-detection data, accounting for imperfect detection.

Population Protecting Implant (PPI): A pH-responsive device implanted in native animals that delivers toxin to predators consuming the host to eliminate problem individuals.

References

1. pH-Responsive Polymer Implants for the Protection of Native Mammals: Assessment of Material Properties and Poison Incorporation on Performance. Polymers (2023).
2. Mesopredator release among invasive predators: Controlling red foxes can increase feral cat density and alter their behaviour. Journal of Applied Ecology (2023).
3. Evaluating the efficacy of a landscape scale feral cat control program using camera traps and occupancy models. Scientific Reports (2018).
4. Human-modified habitats facilitate forest-dwelling populations of an invasive predator, Vulpes vulpes. Scientific Reports (2017).
5. Counting the bodies: Estimating the numbers and spatial variation of Australian reptiles, birds and mammals killed by two invasive mesopredators. Diversity and Distributions (2022).
6. Assessing Risks to Non-Target Species during Poison Baiting Programs for Feral Cats. PLOS ONE (2014).