This data was collected to improve our knowledge and understanding of the marine environment in the upper reaches of East and Middle Arms (Darwin Harbour), to assist planning and sustainable development for the new township. Data provide polygon data that map the benthic habitats (12 physical and biological categories) in the upper reaches of the harbour using remote-sensed and survey data. This dataset is being continually updated and is current as of 03/03/2016.

The goal of the program was developing comprehensive inventories and maps of the distribution and abundance of physical and biological seabed habitats, seagrasses and benthic assemblages to provide baseline environmental mapping and a description of ecological patterns. The benthic habitat mapping was performed by utilising R/Python and Maxent software within the species distribution modelling domain. We correlated the probability of occurrence of individual benthic habitat classes with the environmental predictors developed form the multibeam hydroacoustic dataset. There are five maps for the probability of occurrence of individual benthic habitat classes: Macroalgae, Seagrass, Hard Corals, Filter feeders and Bare seafloor; and a maximum likelihood map incorporating all the individual layers (1- Macroalgae; 2- Filter Feeders; 3- Seagrass; 4- Hard Corals; 5- Bare seafloor). An updated version of this data are available (2022) Revised predictive benthic habitat map for Darwin Harbour. Report prepared for Department of Environment, Parks and Water Security. Australian Institute of Marine Science, Darwin, 127 pp. See related data link below.

This data presents the results of seabed mapping and habitat classification surveys completed in Darwin Harbour during 2011 and 2013 as part of the Northern Territory Government's marine habitat mapping program. This research is a collaboration between Geoscience Australia (GA), the Australian Institute of Marine Science (AIMS), the Department of Land Resource Management (DLRM) and the Darwin Port Corporation. Key objectives are to: - Produce detailed maps of the bathymetry and derived parameters such as slope and rugosity, - Classify the seabed into areas of hard and soft substrate, and, - Produce seabed habitat maps (or seascapes). Key outcomes from the surveys include: 1. Improved understanding of the seabed of Darwin Harbour. The main seabed geomorphic features identified in Darwin Harbour include banks, ridges, plains and scarps, and a deep central channel that divides into smaller and shallower channels. Acoustically hard substrates are found mostly on banks and are associated with rocky reef and sponge gardens, and are often overlain by a thin veneer of sandy sediment. In contrast, plains and channels are characterised by acoustically soft substrates and are associated with fine sediments (mud and sand). 2. Classification of physical seabed properties to produce a Seascape Map for Darwin Harbour. Six seascape classes (potential habitats) were derived using an Iterative Self Organising (ISO) unsupervised classification scheme. These six classes are related to statistically unique combinations of seabed substrate, relief, bedform and presence of sediment veneer (quite often inferred from presence of epibenthic biota).

Inshore benthic habitat mapping of the Adelaide Mount Lofty Ranges (AMLR), Yorke Peninsula, Eyre Peninsula, Upper Spencer Gulf, Upper Gulf St Vincent, South East and Kangaroo Island as part of a wider DEWNR project to map specific areas of the South Australian inshore environments Habitat boundaries were interpreted from underwater features discernable on ortho-rectified aerial photographs. The data for the Upper Gulf St Vincent and Upper Spencer Gulf were captured between 2005 and 2007. AMLR data was captured between 2008 and 2009. South East data was captured between 2009 and 2010. Field observations and underwater video footage was used to capture the Upper Spencer Gulf and Upper Gulf St Vincent data. The AMLR data was captured from field observations, underwater video footage, acoustic mapping and sidescan sonar. The data sets were combined as part of a DENR Statewide project. Additional data was captured on Kangaroo Island during 2013 which included field observations and Underwater video footage. This data was added by regional staff using an adapted data schema that now includes species specific information.

Point data collected from video drops identifying benthic habitats such as seagrass, macroalgae and reef, collected during field work in 2007 to 2011. Used to support the Benthic Habitat Mapping project undertaken by DENR to map the nearshore benthic habitats of South Australia.

The SeaMap Tasmania project undertook mapping of seafloor habitats across the nearshore Tasmanian coastline (0-40 m) - the first state to compile a statewide asssimilated benthic habitat dataset. This initiative comprised of collating aerial photography (from archives), acoustic mapping, and conducting underwater video surveys and field-based visual observations. From this, 1:25,0000 scale habitat maps were created for shallow coastal water to within 1.5 km of the coastline (or 40m depth, which ever was arrived at first). Depth information was collected via acoustic methods and used to discriminate seafloor habitat type, in combination with scanned aerial photographs and towed video transects providing ground-truthing information. See 'Lineage' section of this record for full methodology and data dictionary. This data is also available via the Seamap Australia National Benthic Habitat Layer - a nationally consolidated benthic habitat map. https://metadata.imas.utas.edu.au/geonetwork/srv/eng/catalog.search#/metadata/4739e4b0-4dba-4ec5-b658-02c09f27ab9a

The benthic habitats represented in the MSE include continental shelf seabed habitats, coastal seagrass meadows and mangrove forests. A metapopulation model was used. Due to availability of historical data, models were most fully developed for the continental shelf seabed habitats. Parameter values for the remaining habitat types were derived from available NWS data and scientific literature. Historical extent data was augmented by personal communication through workshops and interviews with residents, divers and scientists with long term NWS experience. Each of the habitat types was modelled using the benthic agent model structure.

Standard deviation of depth was calculated from the bathymetry surface for each cell using the ArcGIS Spatial Analyst Focal Statistics "STD" parameter. Standard deviation of depth represents the dispersion of depth values (in meters) around the mean depth within a square 3x3 cell window. The 2x2 meter resolution standard deviation of depth GeoTIFF was exported and added as a new map layer to aid in benthic habitat classification. Acoustic imagery was acquired for the VICRNM on two separate missions onboard the NOAA ship, Nancy Foster. The first mission took place from 2/18/04 to 3/5/04. The second mission took place from 2/1/05 to 2/12/05. On both missions, seafloor depths between 14 to 55 m were mapped using a RESON SeaBat 8101 ER (240 kHz) MBES sensor. This pole-mounted system measured water depths across a 150 degree swath consisting of 101 individual 1.5 degree x 1.5 degree beams. The beams to the port and starboard of nadir (i.e., directly underneath the ship) overlapped adjacent survey lines by approximately 10 m. The vessel survey speed was between 5 and 8 kn. In 2004, the ship's location was determined by a Trimble DSM 132 DGPS system, which provided a RTCM differential data stream from the U.S. Coast Guard Continually Operating Reference Station (CORS) at Port Isabel, Puerto Rico. Gyro, heave, pitch and roll correctors were acquired using an Ixsea Octans gyrocompass. In 2005, the ship's positioning and orientation were determined by the Applanix POS/MV 320 V4, which is a GPS aided Inertial Motion Unit (IMU) providing measurements of roll, pitch and heading. The POS/MV obtained its positions from two dual frequency Trimble Zephyr GPS antennae. An auxiliary Trimble DSM 132 DGPS system provided a RTCM differential data stream from the U.S. Coast Guard CORS at Port Isabel, Puerto Rico. For both years, CTD (conductivity, temperature and depth) measurements were taken approximately every 4 hours using a Seabird Electronics SBE-19 to correct for the changing sound velocities in the water column. In 2004, raw data were logged in .xtf (extended triton format) using Triton ISIS software 6.2. In 2005, raw data were logged in .gsf (generic sensor format) using SAIC ISS 2000 software. Data from 2004 were referenced to the WGS84 UTM 20 N horizontal coordinate system, and data from 2005 were referenced to the NAD83 UTM 20 N horizontal coordinate system. Data from both projects were referenced to the Mean Lower Low Water (MLLW) vertical tidal coordinate system. The 2004 and 2005 MBES bathymetric data were both corrected for sensor offsets, latency, roll, pitch, yaw, static draft, the changing speed of sound in the water column and the influence of tides in CARIS Hips & Sips 5.3 and 5.4, respectively. The 2004 data was then binned to create a 1 x 1 m raster surface, and the 2005 data was binned to a create 2 x 2 m raster surface. After these final surfaces were created, the datum for the 2004 bathymetric surfaces was transformed from WGS84 to NAD83 using the "Project Raster" function in ArcGIS 9.1. The 2004 surface was transformed so that it would have the same datum as the 2005 surface. The 2004 bathymetric surface was then down sampled from 1 x 1 to 2 x 2 m using the "Resample" function in ArcGIS 9.1. The 2004 surface was resampled so it would have the same spatial resolution as the 2005 surface. Having the same coordinate systems and spatial resolutions, the final 2004 and 2005 bathymetry rasters were then merged using the Raster Calculator function "Merge" in ArcGIS's Spatial Analyst Extension to create a seamless bathymetry surface for the entire VICRNM area south of St. John. For a complete description of the data acquisition and processing parameters, please see the data acquisition and processing reports (DAPRs) for projects: NF-04-06-VI and NF-05-05-VI (Monaco & Rooney, 2004; Battista & Lazar, 2005).

An integrated analysis of biological and geoscientific data collected from the nearshore marine environment of the Vestfold Hills was used to identify benthic habitats and associated communities and examine relationships between benthic community composition and environmental characteristics. A 48 km2 area was surveyed using a multibeam echosounder system (MBES) to produce high-resolution bathymetry and backscatter intensity maps of the seabed. Epibenthic community data and in situ observations of substrate composition and seafloor bedforms and features were obtained from towed underwater video. A comparison of top-down and bottom-up approaches to defining benthic habitats was used to improve understanding of the applicability of mapping methodologies. On a broad scale, both approaches produced habitat classes distinguished largely by geomorphic features, with substrate and depth identified as the main controls of benthic community composition, however, the relationship between benthic community composition and environmental characteristics is complex with many variables contributing to differences in community composition. The top-down approach was based on geomorphic units defined using abiotic characteristics and the assemblages identified within the geomorphic were very broad did not always show clear distinction between assemblages. Conversely, the bottom-up approach generated additional habitat classes, identified clear defining taxa for each class, greater distinction between the benthic communities, and allowed identification of additional environmental factors (i.e. sea ice cover) that influence benthic community distribution that are not discernible from geomorphic information alone. The habitat types identified and mapped using the bottom-up approach include shallow boulder fields and exposed bedrock which are dominated by dense macroalgae communities, and steep slopes, muddy basins and sandy plains which are dominated by invertebrate communities. The results indicate that a bottom-up approach is preferable for benthic habitat mapping, however, where detailed information is not available, geomorphic information provides a reasonable indication of the distribution of benthic habitats and communities. This study highlights the utility of multibeam sonar for interpretation of sea floor morphology and substrate and the multibeam data provide a physical framework for understanding benthic habitats and the distribution of benthic communities. This research provides the scientific context and spatial framework for managing the Vestfold Hills nearshore marine environment and provides a baseline for assessing environmental change.

This polygon spatial dataset describes the benthic habitats likely to occur in marine environments around Gunn Point Peninsula and informs the desktop assessment of the marine biodiversity values for the region. The benthic habitats are inferred from existing information but in most cases require further data collection to validate and refine. Habitat modelling forms the basis of benthic community value assessment for Shoal Bay (Galaiduk et al. 2019). The accompanying report Marine and Coastal Biodiversity Assessment of the Gunn Point Area (2020) forms part of the Mapping the Future Project - Gunn Point. This project has identified land capability, water availability and biodiversity values to support land planning and inform development potential over the Gunn Point area. Reports and maps can be viewed from the webpage: denr.nt.gov.au/land-resource-management/development-opportunities Development Potential of the Gunn Point Area (2020) Biodiversity Assessment of the Gunn Point Area (2020) Groundwater Resources of the Gunn Point Area (2020) Marine and Coastal Biodiversity Assessment of the Gunn Point Area (2020) Soil and Land Resources of the Gunn Point Area (2020) Soil and Land Suitability Assessment for Irrigated Agriculture in the Gunn Point Area (2017) Vegetation Communities of the Gunn Point Area (2020)