Managing South Australia’s (SA) regional fisheries for southern garfish remains challenging and topical. For numerous decades the populations in the northern gulfs have sustained the most significant fisheries for this species. Furthermore, these fisheries have sustained extremely high levels of exploitation, which has resulted in the truncation of populations to a few age classes. This over-exploitation has been addressed through a ‘stock-recovery’ harvest strategy implemented in 2012 that is ultimately aimed at reducing the exploitation rate from 69% to 30% by 2020. However, the current assessments of the regional fisheries are based almost entirely on data from the commercial hauling net sector. Yet, the fished populations, i.e. those occupying inshore waters of <5 m depth in the northern gulfs represent only a small proportion of the distribution of southern garfish throughout the SA gulfs. As such, the characteristics of the garfish populations outside the fished areas, i.e. in the off-shore, northern waters and all southern waters, are currently poorly known. Furthermore, the extent to which recruitment from outside the fished areas contributes to the remarkable resilience and persistence of southern garfish populations to prolonged fishing pressure is also not understood.

Information on the relative abundance, population size and age structures and reproductive potential of southern garfish in unfished areas is needed to assess the status of SA's garfish stocks and to evaluate the suitability of indicators based on commercial fishery data for stock assessment. This information is also needed to understand the remarkable resilience of southern garfish to prolonged high fishing pressure.