Murray cod (Maccullochella peelii) is recognised globally as one of Australia’s premier freshwater angling species and is targeted in both rivers and impoundments. Many of the riverine populations are considered self-sustaining but most impoundments are managed as put-and-take fisheries supported by stocking of hatchery-reared fish. Whilst riverine populations are well-studied, little is known about the ecology of the species in impoundments including their spatial and temporal habitat utilisation and the interacting effects of season and water level fluctuations. Copeton Dam is in the northern Murray-Darling Basin and inundates an area (max. surface area 4,620 h) around three times greater than that of Sydney Harbour. Copeton Dam is considered as one of NSW premier Murray cod fisheries. To elucidate the behaviour of Murray cod in Copeton Dam, we tagged 25 large Murray cod (Mean ± S.E. = 921 ± 33.1 mm) with acoustic tags (Innovasea V16) in late 2022 and mid-2023 with the aim being to track these fish for up to 10 years. Movements are being monitored by a network of 40 receivers deployed throughout the dam and extending up into the inflowing Gwydir River. Preliminary results over the first year of the study (dam fullness >90% down to 65%) have revealed that some tagged fish are utilising all parts of the dam and are at times travelling up into the river above as well. Other fish tended to be more area specific but still utilised home ranges of >10 km2 and moved often and rapidly between habitat patches. Over the coming years as the dam level fluctuates, we will quantify the utilisation of vertical and horizontal space by Murray cod through time, which will allow us to build up a clearer picture of what differing dam levels mean to the fishery. These data will allow us to develop a plan of management to ensure Murray cod fisheries in impoundments throughout NSW are well managed into the future under all conditions.