Knowledge of adult fish movement and stock structure is fundamental to identifying the appropriate spatial scale at which the processes of population replenishment work, and thus the spatial units to which fishery management should be applied. The management of the garfish fishery of South Australia has recently been at a heightened sensitivity due to serious concerns about the sustainability of the fishery. Yet, a comprehensive understanding of fundamental aspects of the life history and population biology of this species is lacking, which significantly impedes identifying the most appropriate spatial management structure. There is no understanding of the movement patterns of the adult fish, and the influence of that movement on the stock structure. Thus, it is not known the extent to which such movement helps sustain different regional populations and the extent to which these are independent and discrete. There is a need to rectify this lack of knowledge and understanding for southern sea garfish, so that management of the South Australian fishery can be applied at the appropriate spatial scale and spatial management units.