Blue mackerel (Scomber australisicus) are a schooling pelagic species that occurs in tropical and temperate waters of the Pacific Ocean. They can be found to depths of 200 m over the continental shelf, although juveniles inhabit inshore waters and shallower waters. Fishing for blue mackerel in the Small Pelagic Fishery (SPF) has historically been focused off southeast NSW, eastern Tasmania and South Australia. Almost all small pelagic stocks are multijurisdictional (that is, managed by both the Australian and state governments) under Offshore Constitutional Settlement arrangements (AFMA (Australian Fisheries Management Authority) 2017). The fishery uses midwater trawl and purse seine gear, but purse seine catches have been negligible for the past several years.

The stock structure of blue mackerel is uncertain. Genetic analysis of samples from southern Queensland, Western Australia and New Zealand indicates population subdivision. Genetic differences have been detected between Western Australia and Queensland, and between Western Australia and New Zealand, but not between Queensland and New Zealand (Schmarr et al. 2007; Whittington et al. 2012). No finer-scale analyses of blue mackerel have been undertaken to further define stock structure. Blue mackerel within the SPF is assessed and managed as separate stocks in the eastern and western subareas (ABARES (Australian Bureau of Agricultural and Resource Economics and Sciences 2017)). This profile focuses on the fishery in the eastern subarea.