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For more than 40 years, marine zoning has played a key role while evolving as partof the adaptive management of the Great Barrier Reef (GBR) Marine Park. Thestatutory zoning plan provides the primary integrating component that prohibitsmany threatening activities and manages the impacts of allowed human activitiesand competing uses by means of various zones, special management areas andother spatial management tools.2. How zoning is applied, however, has changed considerably since the first zoningplan was finalized in 1981. Today, zoning is applied in combination with otherlayers of marine spatial planning; the effective combination of these managementtools provides the integrated approach, considered one of the best for managinga large marine protected area.3. The zoning plan provides the foundation for management of the GBR and is thefundamental component of the integrated marine spatial planning approach ensur-ing high levels of protection for significant areas of the GBR, while also allowingecologically sustainable use.4. The paper outlines the legal and managerial contexts of zoning, providing 38 les-sons that may be useful for marine zoning and ecosystem‐based management else-where. It outlines aspects of zoning that have worked well in the GBR Marine Parkand what has changed in the light of experience and changing contexts, and seeksto clarify various misconceptions about zoning and marine spatial planning.5. The integrated management approach in the GBR utilizes a variety of spatial plan-ning tools, which complement the underlying zoning; some of these comprisestatutory management layers (e.g. designated shipping areas, special managementareas, plans of management, fishery management arrangements, Traditional Owneragreements, defence training areas); other layers are non-statutory (e.g. site plans).6. This paper is written for planners, managers and decision‐makers considering the use ofzoning to achieve effective marine conservation, protection and ecologic

Global climate change is increasingly considered one of the major threats to tropical coastal fisheries, potentially undermining important revenue and food security provided by coral reef ecosystems. While there has been significant and increasing work on understanding specific effects of climate change on coral reef fishes, few studies have considered large-bodied fisheries target species, limiting understanding of the effects of climate change on tropical fisheries. This review focuses on coral grouper (Plectropomus spp., and mainly Plectropomus leopardus), which are heavily fished throughout the Indian and Pacific oceans, and represent an exemplar group to assess potential effects of climate change on coral reef fisheries. In experimental studies, P. leopardus appear to be extremely sensitive to increasing ocean temperature, exhibiting declines in survivorship, aerobic scope and activity with relatively moderate increases in temperature. As such, ongoing ocean warming may jeopardize the catchability of coral grouper and sustainability of reef-based fisheries, especially at low latitudes. Notably, a significant portion of wild stocks of P. leopardus are already exposed to temperatures (≥30 °C) that have been shown to compromise individual performance and body condition. While there are considerable knowledge gaps in predicting effects of global climate change on coral grouper, such as their capacity to avoid, acclimate or adapt to changes in local environmental conditions, current information suggests that there is cause for concern. As such, we take the formative steps to outline both ecological and socioeconomic adaptations that could reduce vulnerability of coral reef fisheries to climate impacts on stocks of coral grouper, using a linked socio-economic framework.

The small mackerels comprising school mackerel (Scomberomorus queenslandicus), spotted mackerel (S. munroi) and grey mackerel (S. semifasciatus) are important and valued species to recreational and commercial fishers in northern Australia. Prior to this project very little was known about the basic biology of, or fisheries for, small mackerels. Each species was found to exhibit distinct life history patterns with differing stock structures. Though there is some overlap between fisheries, there was much spatial and temporal separation of the fisheries, with gill net specialisation for each species targeted by the commercial fishery. Recreational hook and line fisheries for school mackerel and spotted mackerel were important with most of the grey mackerel harvest taken by the commercial sector.

The concentrations of 11 elements in individual whole sagittal otoliths from school mackerel (Scomberomorus queenslandicus) and spotted mackerel (Scomberomorus munroi) collected in east coast waters of Queensland, Australia (16°S to 28°S) were determined by using inductively coupled plasma atomic emission spectroscopy (ICP-AES). Spatial and ontogenetic variation in otolith elemental composition was examined to make inferences about the stock structure of these species. Stepwise canonical discriminant analyses of the concentrations of barium, potassium, magnesium, manganese, sodium, phosphorus, sulphur, and strontium were used to differentiate groups of fish. These analyses identified an optimum grouping of at least two stocks of school mackerel and a single stock of spotted mackerel in the study region, although our results showed that the most informative comparisons were made among fish of the same year class. The age of fish in collected samples produced strongly significant effects on mean elemental composition of otoliths. These patterns offered independent support for hypotheses about stock structure from previous tagging, catch monitoring, ageing, and reproductive studies. Discrimination between school and spotted mackerel stocks will enable the species to be managed on the basis of stock structure throughout their east coast distribution.

Movements of school mackerel (Scomberomorus queenslandicus) and spotted mackerel (S. munroi) in Australian east-coast waters were determined by tag and recapture methods and were used to investigate the stock structure of each species. In all, 4427 school mackerel and 2106 spotted mackerel were tagged and released between 1985 and 1995 in a collaborative tagging exercise with the Australian National Sportfishing Association. School and spotted mackerel were recaptured at rates of 2.1% and 1.8% respectively. School mackerel moved small distances from their release sites (26 ± 55 km, mean ± s.d.; maximum distance, 270 km), with these restricted movements indicating the possible existence of a number of stocks. In contrast, spotted mackerel moved large distances from their release sites (202 ± 290 km; maximum distance, 1100 km). Temporal and spatial movement patterns of spotted mackerel were characteristic of fish from a single stock undertaking a seasonal migration. Commercial harvest information in combination with tagging effort reflected the different movements of school and spotted mackerel and strengthened the suggested stock structure of each species.

Demersal trawl and dredge surveys in 1990 and 1991 recorded taxa (comprising 5 loliginid squids, 7 cuttlefishes, 7 octopuses and 2 dumpling squids). In addition to hosting species distributed broadly in the Indo-West Pacific, the Gulf of Carpentaria represents the most north-westerly extent of the range of some eastern Australian species. Squid catches were lower in the north-western gulf in 1990 and higher in shallower water during the more geographically restricted survey in 1991, whereas cuttlefish were more evenly distributed throughout the different sampling areas in both years. Cephalopods are a minor component in reported domestic fisheries catches where penaeid prawns are targeted. High (though seasonal) squid catch rates were reported annually by Taiwanese trawlers targeting butterfish and squid from certain areas prior to 1979. With the observed population structure of the abundant cephalopod species and relatively high catch rates in some localities during these recent surveys, it is suggested that the cephalopod resources of the Gulf of Carpentaria could support increased commercial fisheries exploitation.