The Denman Marine Voyage (DMV) brought together researchers from the Australian Antarctic Program Partnership (AAPP – AAS4631, Chief Investigator Dr Laura Herraiz-Borreguero), the Australian Centre for Excellence in Antarctic Science (ACEAS – AAS4630, Chief Investigator Prof. Matthew King), Securing Antarctica’s Environmental Future (SAEF – AAS4628, Chief Investigator Prof. Steven Chown), and the Australian Antarctic Division (AAD – AAS4636 and 4556 Chief Investigators Dr So Kawaguchi and Dr Leonie Suter), on a highly collaborative, multidisciplinary research voyage aboard RSV Nuyina to the Denman Glacier region and Shackleton Ice Shelf. The voyage was the first dedicated marine science voyage for RSV Nuyina and represented a significant milestone for the Australian Antarctic Program. This voyage report provides information for the voyage including: - Voyage summary and itinerary - Weather conditions during DMV - Participant list (science team, technicians, media team, medical team, ship crew) - High level science objectives for each of the parties onboard (AAD, AAPP, ACEAS, SAEF) - Individual reports for each scientific working group onboard (background, objectives, methods, report on activities, preliminary results (where relevant)), data management plans, acknowledgements, references) - Media program - ACEAS Outreach - Appendix, with Supplementary Material to be separate to the main report.

Dataset collected at Cape Evans, Antarctica, November 2023 as part of a long-term NIWA benthic monitoring program under the Antarctica New Zealand event number K882A. The dataset includes multiple sea-ice and seafloor hyperspectral imaging transects (10-40 meters long) coupled with normal red, green, and blue (RGB) imagery from a dual camera machine vision system. The data were acquired using the remotely operated vehicle (ROV) HIcyBot system, funded by the Australian Centre for Excellence in Antarctic Research (ACEAS). A GNSS-integrated USBL transponder equipped onto the ROV allowed every frame of the high frequency hyperspectral imager to be timestamped via GPS clock to acoustically provided underwater position and attitude. The dataset also includes hyperspectral imaging scans of sampled/retrieved organisms found at the seafloor, to support habitat mapping algorithm development (e.g., algae, urchins, sea-stars, etc.). The ROV was tested as part of an ACEAS Program 2 subcomponent that involved the design of the new under-ice hyperspectral imaging and photogrammetric payload mounted onto the HIcyBot ROV. The overarching goal of the systems was to be able to acquire information of under the sea-ice sympagic and benthic communities (e.g., biomass and photophysiology) and deliver a multi-scale array of biophysical data that can be assimilated with known information in the region and monitor fine-scale change. Through the analysis of new and existing bio-optical under-ice data, the dataset aims to ultimately envisions the delivery of new monitoring tools and algorithms that can provide support for modelling efforts and reveal complex biophysical processes under a changing Antarctic Sea ice. ***NOTE: Data processing is still underway (April 2025). Please contact Emiliano.Cimoli@utas.edu.au for access to data.***

These data were collected in 2024 for a PhD project, including the dissolved trace metal data and particulate trace metal data from the diatom-Antarctic krill experiment. The particulate trace metal data were collected from diatom culture grown in the lab and Antarctic krill culture sourced from AAD.

Sustainable finfish aquaculture is dependent on a benthic environment that can assimilate and process farm particulate wastes. In Macquarie Harbour, bottom and mid water Dissolved Oxygen levels have reached very low levels, which is associated with an increase in the presence of bacterial mats and a significant decline in the abundance and diversity of benthic fauna. Dissolved Oxygen levels are a major determinant of the response of benthic communities in the harbour over timescales of months to years. This dataset consists of data collected by the real-time dissolved oxygen (DO) monitoring system deployed at three locations in Macquarie Harbour, Tasmania. Loggers were originally established under the Sense-T program, continued under FRDC project 2016-067, and deployed and maintained by IMAS. The system consists of 3 strings of acoustically telemetered, optical fluorescence DO, temperature and depth sensors (VEMCO, Bedford, Canada) which measure DO (% saturation) and temperature (°C) across a depth gradient. Data collected from 01-01-2017 to 19-04-2017 consists of data was collected using the first generation of sensors, while data subsequent to 03-06-2017 was collected using a new generation of tags which contain a tilt instead of a depth sensor.

This dataset is derived from a comparative study evaluating six DNA extraction methods for their efficiency in recovering diatom sedimentary ancient DNA (sedaDNA) from Antarctic marine sediments. Sediment samples were collected from two sites: U1536C (Scotia Sea, West Antarctica) and KC02 (Sabrina Coast, Totten Glacier Region, East Antarctica). Each of the six extraction methods was applied to the same set of samples. Following shotgun metagenomic sequencing, the methods were assessed based on metrics such as diatom DNA recovery, average fragment length, and taxonomic diversity. The purpose of the study was to identify the optimal extraction approach for maximizing the yield and quality of diatom sedaDNA, thereby improving its utility for paleoenvironmental reconstruction.

Climate change is already influencing the worlds oceans. The Kerguelen Plateau as been identified as a climate change hotspot. This study aimed to predict and map how climate change will impact the distribution of demersal fishes. This study uses the published modeled (see https://doi.org/10.25959/4GVK-RM21) to take in predicted oceanographic variables under various IPCC climate change predictions. The oceanographic variables are provided by the FESOM model. Hierarchical models of species communities (HMSC) were used to make predictions in the demersal fish distribution for the 2020s, 2030s, 2040s, and 2050s. Predictions were mapped to explore the regions of change. This record contains all the environmental data, R code, and outputs from this project. Raw RSTS data needs to be requested from the AAD under the authorization of AFMA.

Sustainable finfish aquaculture is dependent on a benthic environment that can assimilate and process farm particulate wastes. In Macquarie Harbour, bottom and mid water Dissolved Oxygen levels have reached very low levels, which is associated with an increase in the presence of bacterial mats and a significant decline in the abundance and diversity of benthic fauna. Dissolved Oxygen levels are a major determinant of the response of benthic communities in the harbour over timescales of months to years. This dataset consist of dissolved oxygen (DO) and temperature data collected using HOBO Dissolved Oxygen loggers (U26-001) deployed at two locations in Macquarie Harbour, Tasmania under FRDC project 2016-067.

The demersal fish assemblages on the Kerguelen Plateau has changed through time. This study aimed to detect, quantify, and map these changes. This study uses existing data collected from the Random Stratified Trawl Survey (RSTS) program administered through the Australian Antarctic Divisions (AAD). Raw RSTS data between 2000 and 2016 was extracted from the AAD database. The RSTS data contains information on the abundance (catch per unit effort, CPUE) on fish. RSTS data were paired with environmental data to be modelled. Hierarchical models of species communities (HMSC) were used to make inferences and predictions in the changes of demersal fish distribution. This record contains all the environmental data, R code, and outputs from this project. Raw RSTS data needs to be requested from the AAD under the authorization of AFMA.

Dataset collected during two field campaigns in the same Antarctic fast ice site (Cape Evans, November/December 2018-19) as part of the AGP and NZARI collaboration over the grant "On Thin Ice: An in situ surveillance system for sea-ice microbial communities". The fieldwork was designed to test the scientific potentials of the IMAS/AGP developed under-ice HI system for mapping temporally dynamic and spatially varying under-ice habitats. The dataset consists of 3 terabytes of HI data acquired both in-situ under a wide range of natural and manipulated light conditions, as well as ex-situ with data acquired using a newly developed ice core scanning approach. The in-situ data are in the form of scanned transects acquired with a HI system capturing transmitted natural sunlight while being deployed beneath sea-ice. The ex-situ data was collected using external light sources illuminating horizontal and vertical sections of extracted ice cores. The dataset includes auxiliary data such as RGB imagery, TriOS RAMSES under-ice irradiance, sky irradiance, and any other measurements or information required to process the data. Other auxiliary data collected include filtered samples of ice core sections for fluorometric Chlorophyll-a (Chl-a) extraction, pigment composition via HPLC (to be processed), and particulate absorption spectra. Media footage (e.g., under-ice ROV videography, under-ice 360 videos, campaign photography of the systems and science) is also included. The dataset includes pre-processed high-resolution under-ice imagery collected from the fast-ice zone using a Sony a6300 camera mounted on a custom under-ice sled system. The imagery was acquired to document the sea-ice underside and analyse spatial patterns associated with amphipod communities from a near-horizontal, grazer-level perspective (publications pending).