IMAS Metadata Catalogue
MACROALGAE (SEAWEEDS)
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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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This dataset contains raw RNA sequencing reads from juvenile Ecklonia radiata (Laminariales) collected from Coal Point, Tasmania, and used in a controlled laboratory experiment examining the effects of temperature and elevated CO₂ on gene expression. Individuals were exposed to three temperatures (6, 16, and 26 °C) under two CO₂ levels: current (~420 µatm) and future (~1000 µatm), representing RCP 8.5 projections. Total RNA was extracted from blade tissue and sequenced on an Illumina NovaSeq 6000 platform to produce 150 bp paired-end reads. The dataset includes raw FASTQ files from 30 biological samples (n = 5 per treatment combination) used for transcriptomic analyses investigating the molecular responses of E. radiata to ocean warming and acidification.
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***This record contains a subset of benthic habitat data from https://doi.org/10.25959/E4S6-GE74 (NESP MaC Project 3.6) rehosted for the purposes of the Seamap Australia collaborative project.*** Seagrass beds are a dominant marine ecosystem of Tayaritja (the Furneaux Group of Islands) in the north-eastern waters off Tasmania. Historical coarse mapping has indicated extensive beds of Posidonia, Amphibolis, Heterozostera, and Zostera species, potentially comprising some of the largest and deepest seagrass extents found in temperate Australian waters. However, limited data on the distribution and ecological value of these seagrass habitats represents a significant knowledge gap in understanding Australia's wetland natural assets. This project mapped the extent, ecological composition, population structure, and blue carbon value of seagrass beds around Tayaritja, in partnership with the Tasmanian Aboriginal Centre, as part of NESP Marine and Coastal Hub Project 3.6. The study area focused on the coastal waters surrounding Flinders Island in the western Furneaux Group, with mapping extending from the high tide line to the depth limit of reliable optical detection (approximately 30 m), based on analysis of field data and satellite imagery capabilities in the region. This metadata record specifically describes the benthic mapping component of the study. A combination of close-range remote sensing methods was used to map the extent and ecological values of seagrass beds. High-resolution satellite imagery from Sentinel-2 (10 m) sensors, combined with bathymetric LiDAR data and oceanographic variables, was used to map baseline seagrass extent and composition. A field campaign deployed a Benthic Observation Survey System (BOSS) and unBaited Remote Underwater stereo-Video system (stereo-uBRUV) at approximately 400 locations to validate remote sensing outputs, collecting field photo quadrats and rhizome cores. From these data, maps were produced showing the extent and coverage of seagrass, sand, and macroalgae, and where possible, seagrass species composition, subject to water depth and clarity constraints. See the "Lineage" section of this record for full methodology.
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This dataset is presented as an Excel spreadsheet containing data that were collected and analysed for the project "𝗞𝗶𝗻𝗲𝘁𝗶𝗰𝘀 𝗼𝗳 𝗻𝗶𝘁𝗿𝗮𝘁𝗲 𝗮𝗻𝗱 𝗮𝗺𝗺𝗼𝗻𝗶𝘂𝗺 𝘂𝗽𝘁𝗮𝗸𝗲 𝗯𝘆 𝘀𝗲𝗮𝘄𝗲𝗲𝗱𝘀: 𝗮 𝗴𝗹𝗼𝗯𝗮𝗹 𝗮𝗻𝗮𝗹𝘆𝘀𝗶𝘀” published in 𝘉𝘰𝘵𝘢𝘯𝘪𝘤𝘢 𝘔𝘢𝘳𝘪𝘯𝘢 by Hurd, CL, Lush H, Gannon T and Britton (2027). Data were collected between May 2025 and July 2025 from published studies on the uptake kinetics of nitrate (NO₃⁻) and ammonium (NH₄⁺) by marine macroalgae from the phyla Chlorophyta, Heterokontophyta and Rhodophyta. Articles were identified through searches on Google Scholar and ISI Web of Science. Each study contained data obtained from laboratory experiments on the rate of Dissolved Inorganic Nitrogen (DIN) uptake rate at a range of DIN concentrations. A total of 82 published studies were located, with 532 distinct data entries. Values of the Michaelis-Menten kinetic constants maximum uptake rate (Vmax) and the half saturation constant (Ks) were extracted from studies that reported saturating uptake, and cases where the pattern of uptake with concentration was linear or biphasic were also recorded. For each study, metadata was extracted and recorded that included: taxonomic information (phylum, order, genus and species), functional group using Steneck and Dethier (1994), the experimental subject (species and algal tissue used e.g. apical, basal), habitat of origin (subtidal, intertidal, or cultured), season of collection, and geographic coordinates of the study location (latitude and longitude). Each of the 82 studies in this dataset includes the full reference (author and year) and a functional DOI where available (as of November 2025).
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Seagrass beds are a dominant marine ecosystem of Tayaritja (the Furneaux Group of Islands) in the north-eastern waters off Tasmania. Historical coarse mapping has indicated extensive beds of Posidonia, Amphibolis, Heterozostera, and Zostera species, potentially comprising some of the largest and deepest seagrass extents found in temperate Australian waters. However, limited data on the distribution and ecological value of these seagrass habitats represents a significant knowledge gap in understanding Australia's wetland natural assets. This project mapped the extent, ecological composition, population structure, and blue carbon value of seagrass beds around Tayaritja, in partnership with the Tasmanian Aboriginal Centre. The study area focused on the coastal waters surrounding Flinders Island in the western Furneaux Group, with mapping extending from the high tide line to the depth limit of reliable optical detection (approximately 30 m), based on analysis of field data and satellite imagery capabilities in the region. This record specifically describes the benthic mapping component of the study. See https://doi.org/10.25959/WRXK-KV06 for imagery annotation data from the field validation campaigns. A combination of close-range remote sensing methods was used to map the extent and ecological values of seagrass beds. The approach developed through this study contributed to the creation of the NESP Standard Operating Procedure (SOP) for Seagrass Mapping using Optical Remote Sensing (https://sustainabledevelopmentreform.github.io/nesp-sop-seagrass-mapping).. High-resolution satellite imagery from Sentinel-2 (10 m) sensors, combined with bathymetric LiDAR data and oceanographic variables, was used to map baseline seagrass extent and composition. A field campaign deployed a Benthic Observation Survey System (BOSS) and unBaited Remote Underwater stereo-Video system (stereo-uBRUV) at approximately 400 locations to validate remote sensing outputs. From these data, maps were produced showing the extent and coverage of seagrass, sand, and macroalgae, and where possible, seagrass species composition, subject to water depth and clarity constraints. See the "Lineage" section of this record for full methodology. Three key types of mapping products were developed: ---Occurrence probability maps--- Continuous probability surfaces (0-100%), modelled from presence/absence data, indicating the likelihood of habitat presence at each pixel for: • Seagrass (all morphologies; > 5% cover observed in underwater field imagery) • Macroalgae species/assemblages • Sand ---Habitat percentage cover maps--- Quantitative estimates of percent cover for each habitat category: • Seagrass (all morphologies) • Macroalgae species/assemblages • Sand ---Derived products--- • Baseline binary presence/extent maps derived from optimised probability thresholds: ○ Seagrass: sgprob > 0.5 & sgprob > macroprob & sandcover < 0.9 ○ Macroalgae: macroprob > 0.5 & macroprob > sgprob & sandcover < 0.9 ○ Sand: sandprob > 0.5 & sandcover < 0.2 • Predicted seagrass species composition of binary extent map. • Fractional cover visualisation: combining cover percentages of multiple habitats into a single composite product • Composite habitat maps: combining binary habitat extents and delineating mixed habitat classes These complementary products serve different purposes: probability maps provide confidence measures, extent maps delineate habitat boundaries, percent cover maps support quantitative analysis of habitat density patterns, and composite habitat maps represent the diversity of mixed habitat classes. Together, they provide a comprehensive understanding of seagrass and associated habitat distribution across the study area.
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Kelps are in global decline due to climate change, including ocean warming. To identify vulnerable species, we need to identify their tolerances to increasing temperatures and whether tolerances are altered by co-occurring drivers such as inorganic nutrient levels. This is particularly important for those with restricted distributions, which may already be experiencing thermal stress. To identify thermal tolerance of the range restricted kelp Lessonia corrugata, we conducted a laboratory experiment on juvenile sporophytes to measure performance (growth, photosynthesis) across its thermal range (4 – 22 °C). We found the upper thermal limit for growth and photosynthesis to be ~ 22 – 23 °C, with an optimum of ~ 16 °C. To determine if elevated inorganic nitrogen availability could enhance thermal tolerance, we compared performance of juveniles under low (4.5 µmol/day) and high (90 µmol/day) nitrate conditions at and above the thermal optimum (16 – 23.5 °C). Nitrate enrichment did not enhance thermal performance at temperatures above the optimum but did lead to elevated growth rates at the thermal optimum 16 °C. Our findings indicate L. corrugata is likely to be extremely susceptible to moderate ocean warming and marine heatwaves. Peak sea surface temperatures during summer in eastern and northeastern Tasmania can reach up to 20 – 21 °C and climate projections suggest that L. corrugata’s thermal limit will be regularly exceeded by 2050 as south-eastern Australia is a global ocean-warming hotspot. By identifying the upper thermal limit of L. corrugata we have taken a critical step in predicting the future of the species in a warming climate.
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Seagrass beds are a dominant marine ecosystem of Tayaritja (the Furneaux Group of Islands) in the north-eastern waters off Tasmania. Historical coarse mapping has indicated extensive beds of Posidonia, Amphibolis, Heterozostera, and Zostera species, potentially comprising some of the largest and deepest seagrass extents found in temperate Australian waters. However, limited data on the distribution and ecological value of these seagrass habitats represents a significant knowledge gap in understanding Australia's wetland natural assets. This project mapped the extent, ecological composition, population structure, and blue carbon value of seagrass beds around Tayaritja. The study area focused on the coastal waters surrounding Flinders Island in the western Furneaux Group, with mapping extending from the high tide line to the depth limit of reliable optical detection (approximately 30 m), based on analysis of field data and satellite imagery capabilities in the region. The field validation component of this study involved deployment of benthic video platforms to capture imagery of seagrass beds and associated ecosystems. A field campaign deployed a Benthic Observation Survey System (BOSS) and unBaited Remote Underwater stereo-Video system (stereo-uBRUV) at approximately 400 locations to collect photoquadrats and validate remote sensing outputs. Imagery annotation was conducted in the SQUIDLE+ platform. The approach developed through this study contributed to the creation of the NESP Standard Operating Procedure (SOP) for Seagrass Mapping using Optical Remote Sensing (https://sustainabledevelopmentreform.github.io/nesp-sop-seagrass-mapping).. See the "Lineage" section of this record for full methodology of field collection techniques. See associated dataset https://doi.org/10.25959/e4s6-ge74 for habitat maps derived from field validation and remote sensing inputs.
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This dataset presents the results of a seafloor habitat modeling exercise for the 'Capes region' of the South-west Corner Marine Park, southern WA. The model classifies five broad habitat types (hereafter 'ecosystem components'): seagrass, macroalgae, sessile invertebrates, bare consolidated substrata, and bare unconsolidated substrata. Modeling was conducted at two spatial scales to assess the effectiveness of using broad-scale (~250 m) spatial covariates derived from bathymetry in mapping habitat classes and to compare the modelling outcomes with those obtained using finer-resolution input data. The fine-scale mapping focused on an IUCN II zone near Margaret River, using a seamless 5 m resolution multibeam bathymetry composite. The broad-scale mapping covered multiple IUCN zones, including the southwestern Geographe Australian Marine Park (AMP), the northwestern tip of the South-west Corner AMP, and the Ngari Capes WA State Marine Park. This component used the 250 m resolution 2023 AusBathyTopo grid from Geoscience Australia. Habitat maps were constructed using (1) the bathymetry data sources described above; (2) ground-truthing observations from stereo-BRUV and BOSS camera systems; and (3) Physical covariates, all smoothed to 5 m or 250 m resolution, for the fine- and broad-scale mapping, respectively. Source datasets are available from: • Geoscience Australia's eCat: https://dx.doi.org/10.26186/145281 (5 m multibeam bathymetry) and https://doi.org/10.26186/148758 (250 m DEM bathymetry) • Squidle+: http://squidle.org/geodata/explore (benthic imagery annotations - see also outputs from NESP MaC Project 2.4: https://doi.org/10.25959/6G5A-3G03) • AODN Portal: https://portal.aodn.org.au/search (IMOS oceanographic datasets). This analysis uses the modelling methodology developed in NESP Project 2.1, which extended the ecosystem component modelling to include all temperate Australian shelf waters at a resolution of 250 m (https://doi.org/10.25959/BVJ7-D984). Analysing the scale effects effects of spatial covarariate inputs was undertaken by NESP Project 2.3, along with exploration of visualisation options regarding prediction certainty in consultation with Parks Australia (management end-users). Further details on sampling design for ground-truthing observations and the modelling techniques are available in the NESP MaC Project 2.1 Final Report: https://www.nespmarinecoastal.edu.au/publication/improving-seabed-habitat-predictions-for-southern-australia. A description on this specific South-west Corner case study and the spatial scale analysis is described in the NESP MaC Project 2.3 Final Report: https://www.nespmarinecoastal.edu.au/publication/improving-knowledge-transfer-to-support-australian-marine-park-decision-making-and-management-effectiveness-evaluation. A selection of mapping (WMS) services are listed in the 'Downloads & Links' section of this record. See the 'Lineage' section for a full description of the data packages available for download, and for more visualisation options.
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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 Wilsons Promontory (VIC). In many cases the dataset involved temporal replication (year scale).
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This record described kelp growth and ecophysiological data relevant to the thermal tolerance of specific warm-tolerant and 'normal' family-lines of giant kelp (Macrocystis pyrifera) from Tasmania, Australia. Australia’s giant kelp forests are listed as a Threatened Ecological Community under the Environment Protection and Biodiversity Conservation Act 1999. Habitat restoration is a potential tool for the conservation and management of giant kelp ecosystems. For habitat restoration to be effective, the cause of habitat decline must be understood and overcome. This is problematic when climate change is driving habitat loss since it cannot be reversed or ameliorated prior to restoration. A previous NESP project led by this team (Project E7, Marine Biodiversity Hub) identified warm-tolerant strains of giant kelp from remnant patches in eastern Tasmania, where the species has experienced precipitous declines due to ocean-warming. These strains have high potential to assist with ‘future-proofing’ kelp forest restoration, however it is still unclear what the physiological mechanisms are that provide their improved thermal tolerance. This work cultivated the warm-tolerant strains of giant kelp previously identified, along with giant kelp strains of normal tolerance, at both cool (16 °C) and warm temperatures (20 °C). The juvenile kelp was then harvested, and a suite of physiological traits that may be responsible for their differences in thermal tolerance were examined. These included nutrient usage (carbon and nitrogen content), cellular membrane processes (fatty acid contents), and photosynthesis (PAM fluorometry and photosynthetic pigments). The cultivation trials again illustrated the improved ability of the warm-tolerant strains to develop at stressful warm temperatures relative to normal giant kelp. This work demonstrated for their first time that the improved thermal performance of these strains may extend to the development and fertilisation of the earlier kelp ‘gametophyte’ life-stage. Despite the clear differences in growth between the two test groups, the physiological assessments illustrated a complex pattern of responses, some of which are contrary to expected based on prior knowledge of thermal performance in kelps. Nonetheless, these results indicate that the warm-tolerant strains of giant kelp have a greater capacity to alter the composition of their fatty acids and may be more efficient users of nitrogen (a key nutrient for growth and development). This new information will help inform ongoing kelp breeding and selection programs for future-proofing kelp restoration in Australia and globally. The improved understanding of the physiology of kelp thermal tolerance might also help with identifying individuals and populations of Macrocystis, and other kelps, that may be resilient to (or especially threatened by) ocean warming and climate change.