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    This study compared the individual and combined effects of two introduced marine species in SE Tasmania - the northern Pacific seastar (Asterias amurensis) and the European green crab (Carcinus maenas) - and investigated their impact on native invertebrate fauna using in situ caging experiments. Both species predate upon bivalves, and this study assessed the biological interaction between these introduced species and native bivalve species - allowing the impact of multiple exotic predator species to be investigated in one system. The cage experiments have 5 treatment groups, including all combinations of presence (single animal) and absence of seastars and crabs, and a control with neither. Predator activity (number and type of bivalves consumed) was recorded after 8 weeks by suction-sampling each cage and counting and identifying fauna.

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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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    Gillnet fishing trials at a number of sites off the east coast of Tasmania have been undertaken to collect samples of the banded morwong, which are characterised based on size, age, maturity stage and sex structure. Otoliths are sectioned for age determination. The dataset comprises a major component of work carried out from the beginning of 2001 and available historic data (1995 to 2000) have also been uploaded into this database to provide a complete dataset. See attached reports for further information.

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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, this dataset refers to the South Bruny Island region, and its 3 subsites: Mangana Bluff, Bay of Islands and Cape Conella.

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    Mesozooplankton community composition and structure were examined throughout the D’Entrecasteaux Channel, Huon Estuary and North West Bay, Tasmania. The data represented by this record was collected as part of a grazing study conducted in North West Bay (1-2 October, 2006). The grazing impacts of microzooplankton and mesoplankton on the phytoplankton communities were examined during several process studies. Experiments with mesozooplankton grazers were restricted to dominant omnivorous copepods (e.g. Acartia tranteri, Paracalanus indicus, Centropages australiensis) cladocerans and appendicularians. Grazing rates of microzooplankton reached as high as 96% of daily primary production, while that of mesozooplankton herbivours was never greater than 20%. Trophic interactions between the species are complicated by the recent arrival of the heterotrophic dinoflagellate Noctiluca scintillans to the region. This species grazes heavily on phytoplankton, smaller zooplankton and faecal pellets. Noctiluca scintillans accounted for up to 20% of mesozooplankton abundance in autumn and it is capable of both suppressing zooplankton abundance and reducing the sedimentation of faecal pellets to the seafloor.

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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 North Bruny Island region, and its 3 subsites: Patrick's Bight, Trumpeter Point and 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, 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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    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 10/03/2005. 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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    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 Fortescue Bay region, and its 3 subsites: Lanterns, Munroe Bight and Thumbs.