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We describe a first estimate of the potential to increase production from Australia’s commercial fisheries based on the difference between current catches and maximum sustainable yield (MSY). MSY is not being advocated as a target reference point but enables a level of consistency across species and/or jurisdictions with different reference points. MSY estimates were obtained for 290 species/stocks that comprised 84% of annual landings. 75% of the estimates were computed using methods applied specifically for this study, aided by an assessment framework, and supporting software. The catch-MSY method was used extensively given the lack of formal assessments for many species, and the limitations of taking this approach are discussed. The results indicated that potential production could be more than double the current national catch (an increase over current catches of about 124%), but potential increases varied considerably among Federal, State and Territory jurisdictions. The potential for increased production was particularly influenced by predictions for highly productive small pelagic fishes, although ignoring the potential for increased catches of these species still led to an estimate of an increase of almost 80% over current catches. Other factors such as whether an increase in production has market demand are also clearly important, along with other social and economic issues. Impacts on ecosystem sustainability and the consequences of climate change were beyond the scope of this study and would need to be considered in separate analyses. However, in making our estimates of potential production we acknowledged the issues with attempting to use single species approaches to provide fish community wide estimates and acted conservatively with our interpretation. Consequently, the results presented in this paper provide useful insights into possible biologically sustainable catches and the potential for increased production.

Coastal and estuarine ecosystems, such as mangroves, tidal marshes and seagrass meadows, provide a range of ecosystem services, but have seen extensive degradation and decline. Effective protection and rehabilitation of coastal ecosystems requires an understanding of how efforts may improve associated ecosystem services. In this study, we present a spatially-explicit angler catch function to predict boat-based recreational catch as a function of ecosystem and angler characteristics. We developed a choice model to investigate where recreational anglers launch their boats and fish in southeast Australia. By linking the recreational catch models with a choice model, we were able to quantify welfare gains of ecosystem rehabilitation. We found welfare gains across fishing locations varied widely due to heterogeneous coverage of seagrass. The welfare gains of different fishing locations ranged from near-zero in areas of low seagrass coverage, to AU $19.18 (10% increase in seagrass area) and to AU $85.55 (30% increase) per trip in location of high seagrass coverage. Given two million fishing trips occurring per year in Port Phillip Bay, and one million in Western Port, the aggregated welfare gain could scale up to AU $6.2 million with a 10% increase in seagrass coverage, and AU $22 million per annum with a 30% increase in seagrass. We also calculated the welfare loss associated with total loss of seagrass ecosystem in each fishing location to represent the current value, which varied significantly, ranging from near-zero in some locations to AU $87.47 per trip in other locations. Over the past several decades, the bay-wide seagrass ecosystem has dropped by 36.7% in Western Port, resulting in potential welfare loss of an estimated AU $ 86.7 million per annum. Our analyses provide insightful spatial policy implications for coastal and marine ecosystem rehabilitation in the region.