Summary

Earth is suffering a biodiversity crisis due to anthropogenic threats including invasive species, habitat destruction, climate change, and human persecution. Important tools for addressing biodiversity loss are creating havens that exclude key threats and restoring the ecosystems within those havens using wildlife reintroductions. However, 25–50% of reintroductions have failed to create self-sustaining populations, due to a number of factors such as poor planning, under-funding, selecting inappropriate founders, failure to address initial causes of decline, and a lack of ongoing post-release monitoring.

Best-practice reintroduction guidelines published by the International Union for the Conservation of Nature state that founders should be selected on the basis of genetic, morphological, physiological, and behavioural representativeness. Each category is important, but several studies have shown the vital influence of individual behavioural syndromes (i.e., personality and plasticity) on reintroduction outcomes. Despite this, there are no known documented cases of selecting founders on the basis of personality and plasticity. This may be due to a lack of rapid field-based behavioural assessment (assay) methods available to practitioners. Most personality studies are conducted in a laboratory environment which is costly and time-intensive and can be stressful and invasive for the animals being assessed.

To address this problem, I designed and tested behavioural assay arenas for use in the field and conducted assays on two eastern quoll (Dasyurus viverrinus) populations at Mulligans Flat Woodland Sanctuary (MFWS) and Goorooyarroo Sanctuary (GS), to investigate how differences in personality and plasticity influence population dynamics for this endangered marsupial mesopredator, with a view to understand how knowledge of these differences can inform future reintroductions. I found significant demographic, morphological, and behavioural differences between the eastern quolls of MFWS and GS. The individuals at MFWS were more likely to be behaviourally proactive (lower latencies to emerge, greater activity levels) and plastic (more able to change behaviour over time). Individuals at GS were more likely to be reactive (greater latencies to emerge, and lower activity levels) and more rigid. These quolls were also more likely to be heavier, have greater body condition scores, and aged 1–2 years old (as opposed to MFWS where their ages covered the full life expectancy of up to 3–4 years old).

Understanding how personality and plasticity differences in individual animals affects reintroductions and ecosystem restoration is still in its infancy, but I have demonstrated a method for conducting rapid behavioural assessments in the field. This provides practitioners with a tool to explore behavioural syndromes and how they influence reintroduction outcomes and population dynamics.