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The distance between where food is produced and consumed is increasing, and is often taken as evidence of an unsustainable global food system. Seafood is a highly traded commodity yet seafood sustainability assessments do not typically consider the impacts of the movement of products beyond the fishery or farm. Here we use life cycle assessment to examine the carbon footprint of the production and distribution of select seafood products that are consumed in Australia and determine differences in the sustainability of imports and their domestically produced counterparts. We found that the distance food is transported is not the main determinant of food sustainability. Despite the increased distance between production and consumption, carbon footprints of meals from imported seafood are similar to meals consisting of domestically produced seafood, and sometimes lower, depending on the seafood consumed. In combining LCA with existing seafood sustainability criteria the trade-offs between sustainability targets become more apparent. Carbon 'footprinting' is one metric that can be incorporated in assessments of sustainability, thereby demonstrating a broader perspective of the environmental cost of food production and consumption.

Prawns and shrimp are among the most popular seafood consumed globally and their production is responsible for a range of environmental impacts in wild capture fisheries and associated supply chains. Management of the Australian Northern Prawn Fishery has been promoted as a sustainable model for other countries to emulate, although broader environmental impacts, such as those relating to energy and water use or greenhouse gas emissions are not currently monitored under sustainability assessments. We use life cycle assessment (LCA) to assess the environmental impacts of the white banana prawn (Fenneropenaeus merguiensis). Fishing operations were the main source of impacts for the supply chain examined, contributing 4.3 kg CO2e kg-1prawn or 63% of the overall global warming potential. This result was lower than emissions reported for other prawn species, including tiger prawns from the same fishery. Processing and storage were key contributors to ecotoxicity while transport made a negligible contribution to any impact category. We discuss how LCA can complement existing fisheries management, and broaden current seafood sustainability assessments including the potential for emerging fishery-specific indicators to improve the efficacy of seafood LCAs.

The concept of seafood sustainability does not typically include the energetic or material demands of the capture or supply chain processes, despite the significant impacts they generate. We used life cycle assessment (LCA) to measure the environmental footprint of the supply of Tasmanian southern rock lobster, Jasus edwardsii (TSRL). International airfreight of live lobsters was the major contributor to global warming potential (GWP) and cumulative energy demand (CED) indicators, while the fishing stage accounted for the majority of impacts to eutrophication potential (EP), water use and marine aquatic ecotoxicity. The environmental footprint of the TSRL in our scenarios was responsive to marine resource management decisions made inside and outside the fishery. Targeting maximum economic yield rather than maximum sustainable yield decreased the carbon footprint by 80% or 10 kg CO2e kg-1of lobster at capture. Limiting access to the fishery by increasing the coverage of marine protected areas increased the fishery's carbon footprint by 23% or 3 kg CO2e kg-1of lobster at capture. The unintended consequences of management changes suggest that in a future of increased carbon emission regulation, marine resource decision making should not be made in isolation of broader environmental impacts.

Several lines of evidence show that ocean warming off the east coast of Tasmania is the result of intensification of the East Australian Current (EAC). Increases in the strength, duration and frequency of southward incursions of warm, nutrient poor EAC water transports heat and biota to eastern Tasmania. This shift in large-scale oceanography is reflected by changes in the structure of nearshore zooplankton communities and other elements of the pelagic system; by a regional decline in the extent of dense beds of giant kelp (Macrocystis pyrifera); by marked changes in the distribution of nearshore fishes; and by range expansions of other northern warmer-water species to colonize Tasmanian coastal waters. Population-level changes in commercially important invertebrate species may also be associated with the warming trend.Over-grazing of seaweed beds by one recently established species, the sea urchin Centrostephanus rodgersii, is causing a fundamental shift in the structure and dynamics of Tasmanian rocky reef systems by the formation of sea urchin 'barrens' habitat. Formation of barrens represents an interaction between effects of climate change and a reduction in large predatory rock lobsters due to fishing. Barrens realize a loss of biodiversity and production from rocky reefs, and threaten valuable abalone and rock lobster fisheries and the local economies and social communities they support. This range-extending sea urchin species represents the single largest biologically mediated threat to the integrity of important shallow water rocky reef communities in eastern Tasmania.In synthesizing change in the physical ocean climate in eastern Tasmania and parallel shifts in species' distributions and ecological processes, there is evidence that the direct effects of changing physical conditions have precipitated cascading effects of ecological change in benthic (rocky reef) and pelagic systems. However, some patterns correlated with temperature have plausible alternati