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  • Intraspecific variation in the thermal tolerance of microscopic giant kelp (Macrocystis pyrifera) sporophytes was tested using a common garden experiment, where 49 unique family-lines were raised under four different water temperatures (12, 16, 20, and 24°C). The unique family-lines were taken from ongoing giant kelp gametophyte cultures held at IMAS, and represented F1 offspring from seven 'selfed' individuals collected from 6 sites across ~250km in Tasmania, Australia, in addition to a site-level cross from each of the sites, and a panmictic cross using the 42 pure family lines. Survivorship of the selected warm-adapted family-lines after outplanting trials at restoration sites can be found here with the associated dataset "NESP Marine Hub Project E7 outplanted kelp survivorship". https://metadata.imas.utas.edu.au/geonetwork/srv/eng/catalog.search#/metadata/908afd8c-cc7a-4ea3-a87e-4497ae8da87a

  • Redmap is a primarily a website that invites the community to spot, log and map marine species that are uncommon in their region, or along particular parts of their coast. The information collected is mapped and displayed on the site, demonstrating, in time, how species distributions may be changing. Sightings are divided into two categories – those with a photo that can be ‘verified’ by a marine biologist, and sightings without photos that we call community sightings (anecdotal). All the information collected, with and without photos, is mapped and will be used in the following years to map out a ‘story’ of changes occurring in our marine environment. The main data collected includes the species sighted (normally selected from a list comprising preselected species of interest), the location, date/time and activity being undertaken. Other optional information gathered include biological data such as sex, size and weight and environmental data such as water depth and temperature and habitat. This record is associated with live data (and will subsequently change over time) and spatial elements have reduced accuracy. It is also subject to a three year embargo (ie. does not contain data less than three years old). If you wish to discuss obtaining a citable, static dataset, that is current and/or contains accurate spatial elements, please see Point of Contact.

  • 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.

  • Data was collected and processed for the project: "Assessment and communication of risks to Tasmanian aquaculture and fisheries from marine heatwaves". Observational data is from NOAA OISST v2.1 (1982-2020), and model data is from 25 CMIP6 models over the historical period (from 1982-2014), with SSP1-2.6 and SSP5-8.5 extensions (out to 2100). Raw sea surface temperature data truncated to the Tasmanian region: 138-155E, 49-35S. Time-series of subdomain area averages are also provided, along with calendar corrections, mean-bias corrections, and seasonal bias corrections for the model data. Further details are provided in Kajtar, J.B. and Holbrook, N.J. (2021): "Future projections of marine heatwave hazards to aquaculture and fisheries in Tasmania", Institute for Marine and Antarctic Studies, University of Tasmania, Australia. 36pp. ISBN: 978-1-922708-06-9. http://ecite.utas.edu.au/147866.

  • The abundance of macroinvertebrates associated with 28 experimental artificial reefs supporting different patch sizes and density of kelp (Ecklonia radiata) off Maria Island, Tasmania. Macroinvertebrates were assessed by diver-based visual census conducted between November 2015 and December 2016. This data was collected to examine how the patch size and density of kelp influences the establishment of macroinvertebrate assemblages.

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    These data are from a voyage (IN2019_V01) on RV Investigator with the Australian Antarctic Division (AAD), that took place during January-March 2019. The Chief Scientist was Mike Double from the AAD. Clara R. Vives collected biogeochemical data on the voyage, and performed a series of incubation experiments for her PhD. The purpose of the study was to investigate the effects of iron and light on phytoplankton growth off East Antarcitca. Data include CTD nutrients, chlorophyll and oxygen as well as underway phytoplankton physiology (measured as the photochemical efficiency) and pCO2. Some data are duplicated but not in exactly the same format on the CSIRO Data Trawler.

  • This record describes Remotely Operated Vehicle (ROV) imagery collected from within the Gascoyne Marine Park offshore northwestern Australia. The ROV SuBastian was used to conduct imagery transects on 20 dives across 16 stations, including 12 quantitative transects within the Cape Range Canyon. No quantitative transects were conducted in the Cloates Canyon due to delays caused by poor weather. SuBastian is equipped with a Sulis Subsea Z70 deep sea science camera, with 4K UHD 2160p optics and sensors for temperature, depth, conductivity and oxygen. The quantitative transects were run for 500 m upslope, ideally at a speed of 0.3 knots and an altitude of 2 m above the seafloor or rock walls. Still images were acquired every 5 seconds, with additional frames added manually as required. Still images from most transects were primarily annotated onboard using the RV Falkor’s private instance of SQUIDLE+, with some post-survey annotation conducted using the public instance of Squidle+ (http://squidle.org/).

  • This record provides an overview of the NESP Marine and Coastal Hub small-scale study - "Australia’s Coastal Shorebirds: Trends and Prospects". For specific data outputs from this project, please see child records associated with this metadata. -------------------- Coastal Australia is home to 37 regularly occurring migratory shorebird species, with many protected areas including Ramsar sites designated on the basis of shorebird populations. Many migratory shorebirds are declining rapidly, and hence the focus of conservation efforts at multiple levels of government in Australia and overseas. However, trend data are now nearly 10 years old, meaning the information available to assess where conservation actions are needed most urgently and whether conservation efforts are helping species recover are outdated. To ensure populations have the best chance at recovery and that resources are allocated where they are most likely to have the greatest positive impacts, it is critical to maintain up-to-date information on species trends. This project analyses 30 years of shorebird monitoring data collected by citizen science groups across Australia and curated by BirdLife Australia’s National Shorebird Monitoring Program.to update national trend estimates, while also assessing the relative effects of human pressure and conservation efforts on population trends. This project will set the stage for building the next decade of coastal shorebird conservation activity in Australia, coordinated through the national mechanism of the End User: National Migratory Shorebird Conservation Action Plan Steering Committee, with representatives from national and state governments as well as leading shorebird experts. Planned Outputs • Regional hotspots of Australian impacts on shorebird populations [spatial dataset] • Final technical report with analysed data and a short summary of recommendations for policy makers of key findings [written]

  • Water quality and biological data was collected from four tide-dominated river estuaries indicative of catchments with varying levels of human impacts to: 1) assess draft indicator levels for water quality, and 2) investigate biological indicators of estuarine health in NW Tasmania. The data represented by this record was collected in the Duck Bay.

  • 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.