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  • NESP Marine Biodiversity Hub Project E7. Results from the outplanting of lab-selected and cultivated warm-adapted genotypes of giant kelp (Macrocystis pyrifera), at two trial restoration sites. A third restoration trial site had no surviving kelp, so those data were not included here. Data and details from lab-selection experiments can be found in the associated dataset - "NESP Marine Hub Project E7 - Macrocystis pyrifera thermal tolerance testing" https://metadata.imas.utas.edu.au/geonetwork/srv/eng/catalog.search#/metadata/0b91d7fd-7d29-452f-954a-78cf75151035

  • 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.

  • Between 2009-2012, Geoscience Australia conducted three surveys to Joseph Bonaparte Gulf and the Timor Sea on the R.V. Solander, in collaboration with the Australian Institute of Science and the Museum and Art Gallery of the Northern Territory. The study areas overlapped the Oceanic Shoals Commonwealth Marine Reserve and the carbonate banks and terraces within it. The surveys were conducted as part of the Australian Government's Energy Security Program (2007-2011) and the National Environment Research Program (2011-2015). On the surveys, a benthic sled was deployed to collect biological samples from the seafloor. Samples were sorted onboard according to phylum, photographed and then sent to taxonomists for species-level identifications. This catalogue includes all onboard photographs taken from identified samples. Sponges were the only group of which all samples were identified, but they include high proportions of unnamed or undescribed species. The catalogue also includes taxonomic identification sheets so that users can cross-reference the species names and images with location and depth.

  • The phenotypic plasticity of habitat-forming seaweeds was investigated with a transplant experiment in which juvenile Ecklonia radiata and Phyllospora comosa were transplanted from NSW (warm conditions) to Tasmania (cool conditions) and monitored for four months. We used multiple performance indicators (growth, photosynthetic characteristics, pigment content, chemical composition, stable isotopes, nucleic acids) to assess the ecophysiology of seaweeds before and following transplantation between February 2012 and June 2012.

  • Sea urchins have the capacity to destructively overgraze kelp beds and cause a wholesale shift to an alternative and stable ‘urchin barren’ state. However, their destructive grazing behaviour can be highly labile and contingent on behavioural shifts at the individual and local population level. Changes in supply of allochthonous food sources, i.e. availability of drift-kelp, is often suggested as a proximate trigger of change in sea urchin grazing behaviour, yet field tests of this hypothesis are rare. Here we conduct a suite of in situ behavioural surveys and manipulative experiments within kelp beds and on urchin barrens to examine foraging movements and evidence for a behavioural switch to an overgrazing mode by the Australian sea urchin Heliocidaris erythrogramma (Echinometridae). Tracking of urchins using time-lapse photography revealed urchin foraging to broadly conform to a random-walk-model within both kelp beds and on barren grounds, while at the individual level there was a tendency towards local ‘homing’ to proximate crevices. However, consistent with locally observed ‘mobile feeding fronts’ that can develop at the barrens-kelp interface, urchins were experimentally inducible to show directional movement toward newly available kelp. Furthermore, field assays revealed urchin grazing rates to be high on both simulated drift-kelp and attached kelp thalli on barren grounds, however drift-kelp but not attached kelp was consumed at high rates within kelp beds. Time-lapse tracking of urchin foraging before/ after the controlled addition of drift-kelp on barrens revealed a reduction in foraging movement across the reef surface when drift-kelp was captured. Collectively results indicate that the availability of drift-kelp is a pivotal trigger in determining urchin feeding modes, which is demonstrably passive and cryptic in the presence of a ready supply of drift-kelp. Recovery of kelp beds therefore appears possible if a sustained influx of drift-kelp was to inundate urchin barrens, particularly on reefs where local urchin densities and where grazing pressure is close to the threshold enabling kelp bed recovery.

  • The data is quantitative abundance of fish and megafaunal invertebrates and algal % cover derived from transect based counts at a wide range of locations across Temperate Australia. The methods are described in detail in Edgar and Barrett (1997). Primarily the data are derived from transects at 5 m depth and/or 10 m depth at each site surveyed. Methods were initially developed for research on temporal changes following protection in Tasmanian MPAs (Maria Is, Tinderbox, Ninepin Point, Governor Island). The data represented by this record was collected in MPA studies and surveys interstate, and was collected from Esperence to Albany (WA). In many cases the dataset involved temporal replication (year scale).

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    This dataset is a compilation of published records of 230Thorium - normalised lithogenic and biogenic fluxes from the Southern Ocean, south of 30S. All age models and derived fluxes were taken as published. Lithogenic fluxes are based on 232Th concentrations. Opal and carbonate fluxes are also included where available. In some cases fluxes had to be derived from published data. LGM values for each core represent an average of observations between 28 - 18 ka BP and Holocene values represent an average of observations from 10 - 0 ka BP. These data were collated as part of modelling study of the Southern Ocean during the LGM (Saini et al, Southern Ocean ecosystem response to Last Glacial Maximum boundary conditions, Submitted to Paleoceanography and Paleoclimatology, 2021)

  • NOTE THIS IS AN ARCHIVED VERSION OF THE GLOBAL FISHERIES LANDING DATA. The current version of the data is available from https://metadata.imas.utas.edu.au/geonetwork/srv/eng/catalog.search#/metadata/5c4590d3-a45a-4d37-bf8b-ecd145cb356d and should be used for all future analyses from 16/01/2019. For any questions about version changes to this dataset, please contact the Point of Contact nominated in this record. Global fisheries landings supplied by a number of agencies (FAO/UN, CCAMLR, NAFO, ICES etc) are mapped to 30-min spatial cells based on the range/gradient of the reported taxon, the spatial access of the reporting country's fleets, and the original reporting area. This data is associated with types of fishing gears. Estimates of illegal, unreported and unallocated landings are included as are estimates of the weight of fisheries products discarded at sea. Mapping the source of fisheries capture allows investigation of the impacts of fishing and the vulnerability of fishing (with its associate food security implications) to climate change impacts.

  • Phytoplankton productivity in the polar Southern Ocean (SO) plays an important role in the transfer of carbon from the atmosphere to the ocean’s interior, a process called the biological carbon pump, which helps regulate global climate. SO productivity in turn is limited by low iron, light, and temperature, which restrict the ef- ficiency of the carbon pump. Iron and light can colimit productivity due to the high iron content of the photosynthetic photosystems and the need for increased photosystems for low-light acclimation in many phytoplankton. Here we show that SO phytoplankton have evolved critical adaptations to enhance photosynthetic rates under the joint constraints of low iron, light, and temperature. Under growth-limiting iron and light levels, three SO species had up to sixfold higher photosynthetic rates per photosystem II and similar or higher rates per mol of photosynthetic iron than tem- perate species, despite their lower growth temperature (3 vs. 18 °C) and light intensity (30 vs. 40 μmol quanta·m2·s−1), which should have decreased photosynthetic rates. These unexpectedly high rates in the SO species are partly explained by their unusually large photosynthetic antennae, which are among the largest ever recorded in marine phytoplankton. Large antennae are disadvan- tageous at low light intensities because they increase excitation energy loss as heat, but this loss may be mitigated by the low SO temperatures. Such adaptations point to higher SO production rates than environmental conditions should otherwise permit, with implications for regional ecology and biogeochemistry.

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    The Huon Commonwealth Marine Reserve (CMR) covers a broad depth range from the inner continental shelf at about 70 m, to abyssal depths of more than 3000 m. The majority of the area is in deep water. The Tasman Seamounts Marine Reserve that was proclaimed in 1999 has been wholly incorporated into the Huon Commonwealth marine reserve. The reserve contains a cluster of seamounts that appear as cone-shaped submerged mountains, which provide a range of depths for a diversity of plants and animals. The peaks of many of the reserve's seamounts are between 750 m and 1000 m below the sea surface and support endemic species, including large erect corals and sponges. Some of the flora and fauna are hundreds and possibly thousands of years old, making them some of the longest-lived animals on Earth. The reserve also provides an important connection between seamounts of the Indian Ocean and the Tasman Sea. This map of the geomorphology of the Huon CMR was prepared for the NESP Marine Biodiversity Hub Theme D (1) project: National data collation, synthesis and visualisation to support sustainable use, management and monitoring of marine assets.