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The fatty acid content and composition of the Antarctic krill Euphausia superba Dana, 1850 were investigated using samples collected by a commercial fishing vessel. This dataset allowed comparison between seasons, years (2013–2016), and different fishing locations. Quantities of omega 3 fatty acids 20:5n-3 and 22:6n-3 (mg/g dry mass; DM) were highest in autumn and decreased through winter to reach a spring low. Quantities of the flagellate marker 18:4n-3 and diatom marker 16:1n-7c were variable and did not display the same seasonal fluctuations. In summer, krill had high percentages (% total fatty acids) of 20:5n-3 and 22:6n-3, total PUFA, and low 18:1n-9c/18:1n-7c ratios, indicating a more herbivorous diet. Krill became more omnivorous from autumn to spring, indicated by increasing ratios of 18:1n-9c/18:1n-7c and percentages of Σ 20:1 + 22:1 isomers. Bacterial fatty acids (Σ C15 + C17 + C19 isomers) were minor components year-round (0.9–1.8 %). Seasonal levels of herbivory and omnivory differed between years, and levels of specific fatty acid ratios differed between fishing locations. The fatty acid 18:4n-3 was a major driver of variability in krill fatty acid composition, with no obvious seasonal driver. This is the first study to report krill fatty acid data during all four seasons over consecutive years. This large-scale study highlights the value of using fisheries samples to examine seasonal and annual fluctuations in krill diet and condition.
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A 12-month program was developed and implemented in order to obtain baseline information on water quality (salinity, water temperature, dissolved oxygen, turbidity, pH, dissolved nutrients, silica), ecological condition as shown by Chlorophyll a, benthic macroinvertebrates, pathogens, and habitat extent determined from habitat mapping. Five key estuaries and coastal waters were assessed in the Southern NRM Region of Tasmania. The data represented by this record was collected in North West Bay.
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The Marine Futures Project was designed to benchmark the current status of key Western Australian marine ecosystems, based on an improved understanding of the relationship between marine habitats, biodiversity and our use of these values. Approximately 1,500 km2 of seafloor were mapped using hydroacoustics (Reson 8101 Multibeam), and expected benthic habitats "ground-truthed" using towed video transects and baited remote underwater video systems. Both sources of information were then combined in a spatial predictive modelling framework to produce fine-scale habitat maps showing the extent of substrate types, biotic formations, etc. Surveys took place across 9 study areas, including the Abrolhos Islands, a group of 122 limestone outcrops surrounded by fringing reed ca. 60km west from the city of Geraldton. The Abrolhos research location is the most northerly of the Marine Futures sampling sites, selected due to the unique mixture of tropical coral reef habitats, and temperate reef and seagrass communities.The hydroacoustics data were processed to construct full coverage maps of bathymetry and textural information.
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Sandy beaches on the north and west coasts of Tasmania, and on Flinders and King Islands were sample between October 1996 and August 1997. At each of 102 sites the strandline fauna was sampled using pitfall traps set overnight during the low tide period. A number of physical and biotic characteristics of each beach were also measured.
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The Whole-Antarctic Ocean Model (WAOM) is based on the Regional Ocean Modelling System (ROMS) with thermodynamic ice shelf interactions following Galton-Fenzi et al. (2012)¹. WAOM simulations of the present-day (year 2007) were used to investigate the physical drivers of Antarctic ice shelf basal melting via an ocean heat budget in a longitudinal framework. Ice shelves buttress the Antarctic Ice Sheet and therefore are critical in the dynamics of ice sheet instability and its contribution to sea level rise. New insights into the seasonal melting mechanisms and its importance at circum-Antarctic scale were investigated in Dias et al (2025)². 1) Galton-Fenzi B, Hunter JR, Coleman R, Marsland SJ, & Warner RC. (2012) Modeling the basal melting and marine ice accretion of the Amery Ice Shelf, Journal of Geophysical Research: Oceans, 117 (C9). https://doi.org/10.1029/2012JC008214 2) Boeira Dias F, England MH, Morrison AK, & Galton-Fenzi B. (2025).: On the seasonal variability of ocean heat transport and ice shelf melt around Antarctica, EGUsphere [preprint], https://doi.org/10.5194/egusphere-2024-3905
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This dataset contains raw RNA sequencing reads from juvenile Ecklonia radiata (Laminariales) collected from Bruny Island, Tasmania, and used in a controlled laboratory heatwave experiment. Individuals were exposed to ambient, single, or repeated marine heatwave treatments to assess the effects of thermal stress and recovery. Total RNA was extracted from blade tissue and sequenced on an Illumina platform to generate paired-end reads. The data represent high-quality raw FASTQ files (n = 30 samples; 5 replicates per treatment per time point) suitable for transcriptomic analyses examining the molecular responses of E. radiata to marine heatwaves.
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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 Maria Island region, and its 3 subsites: Beaching, Bunker and Mistaken Cape.
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Samples of Temperature and Salinity from a CTD profile have been measured at Station 2 in the Derwent Estuary between August 2012 and January 2013.
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Mapping of benthic habitat and seafloor bathymetry of Swanbourne, WA derived from satellite imagery captured on 03 June 2017 at a spatial resolution of 2 m. Mapping extent covered as much of the Defence gazetted waters as possible, to a depth of approximately 18 m based on water clarity. Recently dead or senesced (e.g. winter dieback of leaves) and mobile seagrass have the same satellite signature as live seagrass at spectral resolutions of the sensor (WorldView-2). This ensured areas of winter dieback and/or senescence were captured as areas of seagrass for the purposes of impact assessment.
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The spatial extent of the long spined sea urchin, Centrostephanus rodgersii, was estimated by divers using underwater visual census methods to survey rocky reef habitats at 13 regions along Tasmania's east coast (between Eddystone Point and Recherche Bay). Within each region 3 subsites were surveyed, and within each subsite 4 belt transects were surveyed. Divers recorded depth, percent substrata type, percent C. rodgersii barrens habitat; abundance of urchins (C. rodgersii and H. erythrogramma), rock lobster (J. edwardsii) and abalone (H. rubra). Divers also recorded algal cover (estimated), C. rodgersii barrens and substratum type using set categories (see below).
IMAS Metadata Catalogue