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    Physical and chemical parameters at five Pacific oyster (Crassostrea gigas) growing areas in Tasmania - Pittwater, Pipeclay Lagoon, Little Swanport, Georges Bay and Simpsons Bay - were measured as part of a study to determine the carrying capacity of the areas for oyster farming. The data represented by this record, was collected in Little Swanport. This has provided valuable environmental data for these areas. The hydrodynamic regimes at each area except Simpsons Bay were studied, including high and low water volumes, flushing rates, flow rates and depth contours. Temperature, salinity and concentrations of nitrates, phosphates, silicates and chlorophyll a were measured monthly at several sites in each area. The change in these parameters over different time scales also was examined at two sites in Pittwater and indicated temporal and spatial variability in the environmental parameters measured.

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    Zooplankton samples were collected at two sites in south eastern Tasmania, between the years 2000 and 2001 using two types of plankton net. Samples were collected using horizontal hauls during the daytime only. All copepods, salps and chaetognaths were identified and enumerated.

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    Mesozooplankton community composition and structure were examined throughout the D’Entrecasteaux Channel, Huon Estuary and North West Bay, Tasmania, from November 2004 to October 2005, the data represented by this record was collected on the 08/06/2005. The composition of the mesozooplankton community was typical of inshore, temperate marine habitats, with seasonally higher abundance in summer and autumn and lower numbers in winter and spring. Copepods were the largest contributors to total abundance across all seasons and stations, while cladocerans and appendicularians were proportionally abundant in spring and summer. The faecal pellets of these three main groups, along with those of krill and amphipods, also contributed significantly to material recovered from sediment traps. Meroplanktonic larvae of benthic animals showed short-term peaks in abundance and were often absent from the water column for long periods. Spatially, North West Bay and the Channel had a higher representation of typically marine species, including Calanus australis and Labidocera cervi, while truly estuarine species, such as the copepod Gladioferens pectinatus, were more important in the Huon Estuary.

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    In fishing trials, the short term survival rates for hook caught flathead (Platycephalus bassensis in Tasmania and P. fuscus in Queensland) were examined to determine critical factors affecting post-release survival. Biological information (size) and hooking location/damage were recorded and fish held for several days in aquaria to assess survival rates. In order to relate hooking location and catch rates for a range of hook types (including circle hooks) structured fishing trials and volunteer fishers (using a diary system) provided information on fish size, hook type and hooking location.

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    Quantitative surveys were undertaken at four sites in the Kent Group, north eastern Tasmania (southern and northern shores of East Cove at Deal Island, Winter Cove at Deal Island, NE coast of Dover Island) by divers using underwater visual census methods to survey the reef habitat.

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    The spatial extent of C. rodgersii "barrens" was estimated by surveying rocky reef habitat with a towed underwater video system. Sampling took place at 13 regions along the east coast of Tasmania, each comprising 3 subsites, this dataset refers to the Forestier Peninsula region, and its 3 subsites: Sisters, Visscher Island and High Yellow Bluff.

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    The spatial extent of C. rodgersii "barrens" was estimated by surveying rocky reef habitat with a towed underwater video system. Sampling took place at 13 regions along the east coast of Tasmania, each comprising 3 subsites. Substrate and habitat type were recorded using video analysis, with 4 categories of urchin barren habitat recognised (see below for definitions).

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    The spatial extent of C. rodgersii "barrens" was estimated by surveying rocky reef habitat with a towed underwater video system. Sampling took place at 13 regions along the east coast of Tasmania, each comprising 3 subsites, this dataset refers to the Four-mile Creek region, and its 3 subsites: Falmouth, Ironhouse Point and Saltwater Inlet.

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    The spatial extent of C. rodgersii "barrens" was estimated by surveying rocky reef habitat with a towed underwater video system. Sampling took place at 13 regions along the east coast of Tasmania, each comprising 3 subsites, this dataset refers to the St Helens region, and its 3 subsites: Binalong Bay, St Helens Island and St Helens Point

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    The spatial extent of C. rodgersii "barrens" was estimated by surveying rocky reef habitat with a towed underwater video system. Sampling took place at 13 regions along the east coast of Tasmania, each comprising 3 subsites, this dataset refers to the Bicheno region, and its 3 subsites: Denison, Governor Island and Lodi.