This record describes the outputs of two different modelling exercises that were used to characterise the seafloor habitats for temperate Australian waters. The modelled area includes all shelf waters (<250m depth) in southern Australia south of the Tropic of Capricorn. Bioregional benthic habitat maps were constructed using (1) the Geoscience Australia 250m 2023 grid (ref); (2) ground-truthing observations derived from horizontally facing imagery from stereo-BRUV and BOSS camera systems; and (3) several physical datasets as covariates in model development (all oceanographic variables smoothed to 250m resolution). Source data is available from Geoscience Australia's eCat: https://doi.org/10.26186/148758 (bathymetry), Squidle+: (benthic imagery annotations), and (3) AODN Portal: https://portal.aodn.org.au/search (IMOS oceanographic datasets). The specific subset of GA observations used in this modelling exercise is available from https://github.com/UWA-Marine-Ecology-Group-projects/nesp-2.1/blob/main/data/tidy/NESP-2.1_broad-habitat.csv. See the NESP Mac Project 2.1 final report for a description of the sampling design for ground-truthing observations and annotation technique. -----Functional Reef model (binomial)----- This model discriminates ‘functional reef’ from sediment (non-reef) ecosystem types. Functional reef is defined by this project as “any seabed area functioning as a reef, which may include dense beds of sessile invertebrates or molluscs”. This term was chosen because much of the continental shelf is dominated by sediment yet is stable enough to support emergent sessile biota that provide structure and resources for “reef-affiliated” species. The modelling approach uses a Bayesian representation of a Binomial generalised linear model. For ground-truthing benthic annotations, the following benthic categories were collapsed into the ‘functional reef’ classification: sessile invertebrates, bare rocky reef (consolidated), macroalgae, Amphibolis spp. and Thalassodendron spp. All other benthic classifications were assigned to the ‘non-reef’ category. -----Ecosystem Component model (multinomial)----- This model discriminates between five broad habitat types (hereafter ‘ecosystem components’): seagrass, macroalgae, sessile invertebrates, bare consolidated substrata, bare unconsolidated substrata. The modelling approach uses a Bayesian implementation of a Multinomial generalised linear model. For ground-truthing benthic annotations, benthic annotations for mobile species (e.g. echinodermata) were discarded. All remaining annotations were collapsed into the five broad ecosystem components. 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.

The Seamap Australia National Benthic Habitat Layer (NBHL) is a compilation of benthic habitat datasets obtained from various sectors including research, government, industry and community sources, across Australia. These disparate datasets have been integrated into a single national-scale benthic habitat database, and classified uniformly under a national classification scheme implemented as a controlled vocabulary (https://vocabs.ardc.edu.au/viewById/129). Creation of this classification scheme complements work undertaken by the National Environmental Science Program (NESP) Marine Biodiversity Hub (Theme D). The Seamap Australia NBHL can be viewed, analysed and downloaded from the Seamap Australia data portal (https://seamapaustralia.org/map) – a national repository of seafloor habitat data and a decision support tool for marine managers. The NBHL is supplied through Web Mapping Services (WMS) alongside relevant contextual information, in an interactive mapping portal. All habitat datasets in the Seamap Australia data portal, including the NBHL and all local- to regional-scale contributing datasets, are available for download. The Seamap Australia NBHL is a data collection of national importance and highlights the diversity of benthic habitats across Australia’s marine estate. This is the first Australian habitat dataset that seamlessly consolidates data from each of Australia’s state and territory providers. This dataset should be considered a “live” asset and will continue to develop as more suitable validated habitat data becomes available for inclusion, and improvements in data collection and analysis techniques enhance its resolution and currency. The most current (2024) version of the data is available from the following endpoints: WMS: https://geoserver.imas.utas.edu.au/geoserver/seamap/wms WFS: https://geoserver.imas.utas.edu.au/geoserver/seamap/wfs Layer name: SeamapAus_National_Benthic_Habitat_Layer A download link for the full dataset is supplied in the “Online resources” section of this record, along with download links to older versions of the dataset. Note that data is now only available in Geodatabase (.gdb) format as it exceeds Shapefile size limits.

This dataset is a mosaicked product of all publicly available bathymetry data within the Australian Exclusive Economic Zone (EEZ). The data package consists of 8x bathymetry mosaics (and associated bathymetry derivatives: hillshade, slope, aspect) for each of the 8x Parks Australia Management Effectiveness (ME) Depth Zones. The grid resolution of the mosaics has been guided by the depth gridding recommendations of the AusSeabed Australian Multibeam Guidelines (2020) to produce the following mosaics: • shallow zone (0-30m): 10m resolution • mesophotic zone (30-70m): 10m resolution • rariphotic zone (70-200m): 10m resolution • upper-slope zone (200-700m): 32m resolution • mid-slope zone (700-2,000m): 64m resolution • lower-slope zone (2,000-4,000m): 128m resolution • abyss zone (4,000-6,000m): 210m resolution • hadal zone (>6,000m): 210m resolution A systematic prioritisation approach was used to preferentially use newer, high-resolution, and cleaner bathymetry inputs from remote sensing (multibeam, singlebeam, satellite, seismic etc), with Digital Elevation Models (DEM) used as foundational data in regions where survey data was not available. This approach optimised spatial resolution by preserving higher resolutions in shallower waters as supported by the data, while also ensuring the output datasets remain manageable for downstream applications. The result is suite of depth-stratified bathymetry mosaics and associated derivatives that provide full coverage of Australia's marine estate (clipped to the boundaries of the Australian Exclusive Economic Zone (EEZ)). All publicly available bathymetry data as at February 2024 for was included. Data can be visualised and used in GIS packages as maps of hillshaded bathymetry and hillshaded slope at the following WMS endpoints: • bathymetry: https://geoserver.imas.utas.edu.au/geoserver/bathy_composites/AusEEZ_bathy_composite_multires/wms?request=GetCapabilities&service=WMS • slope: https://geoserver.imas.utas.edu.au/geoserver/bathy_composites/AusEEZ_bathy_slope_composite_multires/wms?request=GetCapabilities&service=WMS • aspect: https://geoserver.imas.utas.edu.au/geoserver/bathy_composites/AusEEZ_bathy_aspect_composite_multires/wms?request=GetCapabilities&service=WMS • aspect-slope (for mapping applications only): https://geoserver.imas.utas.edu.au/geoserver/bathy_composites/AusEEZ_bathy_aspectSlope_composite_multires/wms?request=GetCapabilities&service=WMS Data is available for download in the following packages (each structured as 8x mosaics for each ME Depth Zone at the gridding resolution specified above): (1) bathymetry composites; (2) hillshade composites; (3) slope composites; (4) aspect composites. An ancillary Shapefile footprint index file is also available showing the source data used in generating each region of the mosaics. Note that minimal cleaning of input data was conducted, and no attempt was made to smooth or blend the transitions between swath edges, or between swaths and the underlying DEMs. Consequently, noise and edge effects between adjacent input data may be visible. This should be considered when interpreting the data, and the data should not be used for navigational purposes. See the Lineage section of this record for full methodology.

This is a database of nature-based ("soft" or "hybrid") coastal protection projects from across Australia. The database will act as a tool to help coastal managers make informed decisions by providing as many examples as possible of where these solutions have been used, how they were used and how effective they are in different contexts. The information in this database was collected through direct engagement with coastal managers and stakeholders, a literature search, and informal internet searching.