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    Aerial reconnaissance and photography are used in the Ross Sea sector of Antarctica to determine the breeding locations of Adélie penguins and to count the numbers of nests occupied during the early incubation period. From 1981 to present (two-year embargo), all islands and sea coasts between 158°E and 175°E have been searched, and 11 previously unreported breeding colonies discovered. The aim is to census Adélie (Pygoscelis adeliae) populations to provide basic data against which future population levels can be compared in order to monitor environmental change of the Antarctic Ocean ecosystem, both natural and man-induced. GET DATA: https://datastore.landcareresearch.co.nz/en_AU/dataset/adelie-penguin-census-data

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    Knowledge of recruitment dynamics, and in particular trends in recruitment and recruitment variability, are key inputs for integrated assessments of fish stocks. A quantitative longline survey monitoring the recruitment of Antarctic toothfish (Dissotichus mawsoni) in the southern Ross Sea was started in 2012. The survey was expanded in 2016 to monitor trends and biological characteristics in two areas of importance to predators, Terra Nova Bay and McMurdo Sound, and to collect data that would contribute to the research and monitoring plan for the Ross Sea region Marine Protected Area. In most years, the survey was completed as planned, while in three years several factors have constrained the survey from sampling all stations and in the latest two seasons pandemic travel restrictions have necessitated an alternative delivery approach. Between 2012 and 2022, 2 056 tagged Antarctic toothfish have been released on the survey and 21 toothfish have been recaptured. Fifteen pop-up satellite archival tags (PSATs) were deployed on D. mawsoni in 2019 and fifteen skates were tagged in 2020 and 2021. Many tagged toothfish released from the RSSS move from the shelf to the slope. Trends in abundance indices and size and age composition consistently show the progression of strong year classes entering and leaving the survey area and have indicated that recruitment is likely more variable than previously thought. Data from the RSSS have been used to indicate year class strength in Antarctic toothfish stock assessments since 2015. The twelve surveys to date have resulted in a substantive increase in the knowledge and understanding of the distribution and relative abundance of a range of demersal fish species and invertebrate taxa caught on the longlines. Other data routinely collected on the surveys were plankton, temperature, salinity, air quality, cetacean and other marine mammal observations, and photo, video, and echosounder data. The RSSS has provided synergies with other research programmes also addressing CCAMLR objectives, particularly those focused on research and monitoring within the RSrMPA. GET DATA: https://www.ccamlr.org/en/publications/statistical-bulletin

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    Radiolarians (holoplanktonic Protozoa) found in marine sediments are commonly used in Southern Ocean as palaeoclimate proxies. Generating such reconstructions of past climate based on radiolarian abundances requires a spatially and environmentally comprehensive reference dataset of modern radiolarian census counts. The Southern Ocean RADiolarian (SO-RAD) dataset includes census counts for 237 radiolarian taxa from 228 surface sediment samples located in the Atlantic, Indian and South-west Pacific sectors of the Southern Ocean. This compilation is the largest radiolarian census dataset derived from surface sediment samples in the Southern Ocean. The SO-RAD dataset may be used as a reference dataset for palaeoceanographic reconstructions, or for studying modern radiolarian biogeography and species diversity. RELATED PUBLICATION: https://doi.org/10.5194/essd-13-5441-2021

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    Plot data Mc Nemar: To enable comparisons with the 1961 and 2004 survey results, the Lambert Conformal Conic projection from the 2004 survey was used to precisely georeference and trim the RGB image across a 1-m2 grid, generating a total of 3,458 1-m2 grid cells. For each grid cell moss, lichen, or algae/cyanobacteria cover was extracted as one of the four cover classes: Heavy (>40%), Patchy (10–40%), Scattered (less than 10%), and None (0%) for the survey years 1962, 2004 and 2018. Ground truthing: To test the overall accuracy of cover classifications and ensure consistency with 2004 survey methodologies, a ground-truthing approach was performed. Photographs were taken of individual cells along eight transects, running west to east across the plot at 0.5, 1.5, 15.5, 16.5, 28.5, 29.5, 116.5 and 117.5 m distance from the NW corner. Each grid cell could be identified individually with an x/y coordinate in the centre and was surrounded by a rectangular frame parallel to the outer edge of the plot. A total of 174 photographs were taken and archived with Antarctica New Zealand. For each photographed grid cell, the presence of each functional group of vegetation and their cover class was assessed visually. Orthomosaic image: Aerial images were obtained using a DJI Matrice 600 Pro hex-rotor remotely piloted aircraft system equipped with a Canon EOS 5Ds camera (image size: 8688×5792 pixels, focal length: 50 mm, pixel size: 4.14 μm) on November 28, 2018. The flight altitude was 30 m above ground level, and a total of 10 ground-control points were included to provide accurate geo-referencing. An orthomosaic photo and accompanying DEM was generated with the acquired aerial images using Agisoft PhotoScan (now known as Metashape by Agisoft LLC, https://www.agisoft.com/) RELATED PUBLICATION: https://doi.org/10.1029/2022EF002823 GET DATA: https://doi.org/10.7488/ds/3417

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    Diatom census counts were used to quantitatively estimate summer sea-surface temperatures (SST) over the last 40,000 years in core MD11-3353, collected in 2011 on board the R.V. Marion Dusfresne west of Kerguelen Island, Southern Ocean. The transfer function used to reconstruct summer (January to March) SST is the Modern Analog Technique that here uses 249 surface sediment samples (modern analogs), the relative abundances of 32 diatom species and the chord distance to select the five most similar modern analogs (Crosta et al., 2020). This method yields a root mean square error of prediction of ~1 °C. The core chronology is detailed in Thöle et al. (2019). RELATED PUBLICATION: Civel-Mazens, Matthieu; Crosta, Xavier; Cortese, Giuseppe; Michel, Elisabeth; Mazaud, Alain; Ther, Olivier; Ikehara, Minoru; Itaki, Takuya (2021): Impact of the Agulhas Return Current on the oceanography of the Kerguelen Plateau region, Southern Ocean, over the last 40 kyrs. Quaternary Science Reviews, 251, 106711, https://doi.org/10.1016/j.quascirev.2020.106711

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    This metadata record represents environmental DNA sequence data and metadata barcode file. Seawater and sponge eDNA metabarcoding sampling was conducted at seven coastal locations (Cape Barne, Cape Evans, Cziko Seamount, Granite Harbor Middle, Granite Harbor South, and Turtle Rock) in the Ross Sea to assess spatial eukaryote biodiversity patterns and investigate eDNA signal differences between both substrates. Five replicate 500 mL water samples were collected at each of seven locations within 2 m of the ocean floor using a Niskin bottle. At the same time, five sponge specimens were collected by ROV at a depth range of 18–30 m from three out of the seven locations, thereby enabling sponge and near-bottom water eDNA signal comparison. Details of laboratory procedures can be found in the related publication. RELATED PUBLICATION: https://doi.org/10.1002/edn3.500 GET DATA: https://figshare.com/projects/Unveiling_the_Hidden_Diversity_of_Marine_Eukaryotes_in_the_Ross_Sea_A_Comparative_Analysis_of_Seawater_and_Sponge_eDNA_Surveys/186127