Small, isolated populations such as those found on islands are at an increased risk of extinction. This includes K'gari (Fraser Island) wongari (dingoes). Although aspects of wongari ecology and behaviour are well documented, much about population dynamics remains uncertain. Even where relevant research has been conducted (e.g. population abundance), results remain equivocal. We conducted a population viability analysis (PVA) to investigate the influence of different abundance estimates, along with variable rates of mortality, carrying capacity, catastrophes and breeding success on extinction probability. In favourable, undisturbed conditions, modelling showed a high probability of population persistence over 50 and 100 years. Consistently high levels of mortality resulted in increased extinction probabilities, especially at low- and mid-level population sizes. Promiscuous breeding behaviour, higher female breeding success, and higher male availability reduced extinction probabilities. Our approach demonstrated the utility of population viability analysis for identifying important factors that meaningfully contribute to wongari extinction risk. However, inferences and actionable recommendations for managers were limited owing to a paucity of information for certain, critical parameters. Our findings highlighted the need for better data on wongari reproduction and mortality to help fill significant knowledge gaps required to accurately predict the long-term survival of this iconic population.