Rahil Jasminkumar Amin , Jessie C. Buettel, Matthew Fielding, Peter Vaughan, Barry W. Brook 

Modelling the spread of introduced ecosystem engineers is a conservation priority due to their potential to cause irreversible ecosystem-level changes. Existing models predict potential distributions and spread capacities, but new approaches that simulate the trajectory of a species’ spread over time are needed. We have developed novel simulations that predict spatial and temporal spread, capturing continuous diffusion-dispersal with occasional long-distance leaps. We focused on the introduced population of Superb Lyrebird (Menura novaehollandiae) in Tasmania, Australia. Initially introduced as an insurance population, lyrebirds have become novel bioturbators, spreading across key natural areas and becoming "unwanted but challenging to eradicate". Using multi-scale ecological data, our research (1) identified broad and fine-scale correlates of lyrebird occupation and (2) developed a spread simulation guided by a pattern-oriented framework. This occurrence-based modelling framework is useful when demographic data are scarce. We found that the cool, wet forests of western Tasmania, with dense leaf litter and open understories, offer well-connected habitats for lyrebird foraging and nesting. By 2023, lyrebirds had reached quasi-equilibrium within a core range in southern Tasmania, and were expanding northwest, with the frontier reaching the western coast. Our model forecasts that by 2085, lyrebirds will have spread widely across suitable regions of western Tasmania. By pinpointing current and future areas of lyrebird occupation, we provide land managers with targeted locations to monitor the effects of their expansion. Our findings offer an evidence-based approach for future monitoring and provide a framework for understanding the dynamics of other range-expanding species with invasive potential.