Understanding the spatial scale of fish movement, and the environmental triggers for this movement, are essential to support the life-history needs of migratory species in fragmented habitats. Golden perch (Macquaria ambigua) commonly occur throughout the Murray-Darling Basin (MDB) and require long uninterrupted stretches of flowing water habitat to enable the movement and redistribution of juveniles and adults, and to facilitate spawning, and downstream dispersal of pelagic eggs and larvae into productive riverine and floodplain nursery habitats. Recent evidence has highlighted the importance of the mainstem Barwon-Darling River and several key northern basin unregulated tributaries, in providing hydrological conditions conducive to successful spawning and recruitment of golden perch following rainfall when river discharge increases. Due to the variable nature of the hydrology in the northern MDB, limited information on the timing, distance and direction of adult movements exists, particularly during elevated discharge when movements are likely to be maximised. We undertook a 3-year (i.e., 2021-2024) telemetry study to quantify the mainstem and tributary movements of 150 adult golden perch over a period that encompassed numerous high flow events and flooding. Approximately 75% of tagged golden perch undertook movements >50 km, with most (>90%) movements in an upstream direction and extending up to 1500 km. Numerous tributary entry events occurred, and we provide quantitative relationships between river discharge metrics and tributary entry, as well as initiation and cessation of long-distance movements. We provide evidence of the potential migration distances when a species is unconstrained by barriers that can be used to support inter-regional management actions including protection and delivery of future flow events as well as barrier remediation for golden perch and other vagile species.