Description: CSIRO has prepared this dataset in partnership with the Australian Government Department of Climate Change, Energy, the Environment and Water (DCCEEW) for use in biodiversity assessment and national reporting such as State of the Environment, Ecosystem Accounting, Ecological Knowledge System, and annual corporate reporting metrics for the environment and heritage portfolio. The HCAS v3.3 is a 90m gridded dataset depicting habitat condition on a scale between 0.0 (ecosystem removed) and 1.0 (ecosystem in reference condition) for continental Australia. The index represents the contribution that a given site (90m grid cell) makes to the effective area of ecosystem integrity remaining within any given spatial reporting unit, expressed as a proportion of the contribution made by a site in reference condition. Ecosystem integrity is defined as the ecosystem’s capacity to maintain its characteristic composition, structure, functioning and self-organisation over time within a natural range of variability. Reference condition is defined as the condition against which past, present and future ecosystem condition is compared to in order to measure relative change over time. Habitat condition (syn. ecosystem condition) is a generalised estimate for use in whole of biodiversity assessment metrics and may not represent the specific habitat quality requirements of all component species. The data provided is a long-term epoch (also known as the ‘base model’) derived from Geoscience Australia’s archive of Landsat Earth observation remote sensing variables averaged over 37 years (1988-2024) – HCAS33_HCB_1988_2024.tif.This long-term epoch provides the overall ‘best’ estimate of habitat condition derived from the HCAS method, as an expression of the long-term pattern of ecosystem dynamics and capacity to recover following disturbance. The data is provided as a cloud optimised GeoTIFF (COGs) to facilitate use in web applications, 90 m grid resolution, Geographic Datum of Australia (GDA) 1994 (Australian Albers, EPSG:3577). HCAS v3.3 (production version 3) was derived using 'ClassicHCAS' software version 0.2.0 and 'HCAS-workflow' software version 1.2.1.Data extent is defined by any data pixel intersecting a coastline polygon as defined by the land fraction dataset (Liu 2024). The data and no-data extent of each grid layer encompasses the area within the Australian Continental Exclusive Economic Zone (EEZ) (Alcock et al., 2020), excluding territories of Cocos, Christmas, Norfolk, Macquarie, Heard, and McDonald Islands, as well as Antarctica (Liu and Newnham, 2024).The following publication, which describes the data, will be released in 2026: Williams KJ, Liu N, Valavi R, Levick SR, Lehmann EA, Collings S, Giljohann KM, Johnson S, Botha EJ, Munroe SEM, Van Niel TG, Newnham G, Paget M, Malley C, Carlile P, Gunawardana D, Lyon P, Richards AE, Tetreault-Campbell S and Ferrier S (2025) Habitat Condition Assessment System (HCAS) version 3.3: Guide to the 90-metre data collection. Technical report EP2025-2979. CSIRO, Canberra, Australia.The data collection is available at: Valavi R, Levick SR, Lehmann EA, Liu N, Giljohann KM, Williams KJ, Collings S, Johnson S, Botha EJ, Munroe SEM, Van Niel TG, Newnham G, Paget M, Malley C, Carlile P, Gunawardana D, Lyon P, Richards AE, Tetreault Campbell S and Ferrier S (2025) HCAS 3.3 (1988-2024) base model estimate of Habitat Condition (90m grid), National Connectivity Index 2.0 (NCI) and annual time series for continental Australia. Data collection 65549. CSIRO, Canberra, Australia. Landing page: https://data.csiro.au/collection/csiro:65549.
Copyright Text: The Habitat Condition Assessment System for Australia is an ongoing partnership between CSIRO and the Australian Government Department of Climate Change, Energy, the Environment and Water (DCCEEW).
The work presented in this document and data collection was funded by DCCEEW through the Priority Improvements to the Habitat Condition Assessment System project, the HCAS v3.x Update to 2023 project, and the National Ecosystem Accounting Project.
CSIRO and DCCEEW acknowledge the Traditional Owners of country throughout Australia and recognise their continuing connection to land, waters and culture. We pay our respects to their Elders past and present. View CSIRO’s vision towards reconciliation and DCCEEW’s Statement of Commitment to First Nations people.
Geoscience Australia is acknowledged for the Digital Earth Australia Surface Reflectance NBART Landsat Collection 3 GeoMedian, GeoMAD and Fractional Cover derived products, version 4.0.0. Ross Searle and contributors to the Terrestrial Ecosystem Research Network (TERN) are acknowledged for the compilation of 90 m environmental covariates and the Soil and Landscape Grid for Australia (SLGA) collections. We also acknowledge ABARES for supporting the multiple lines of evidence approach to the spatial delineation of reference sites by providing a draft list of authoritative datasets (i.e. produced and managed by State and Territory agencies) relevant to land use mapping.
The Vegetation, Assets, States and Transitions (VAST) classification of condition scores involved the reuse of expert-elicited data collected as part of the Regional Ecosystem Accounting Pilot (REAP) project: ethics clearance 115/22. The reuse of this data was approved by CSIRO’s Social Science Human Research Ethics Committee (CSHREC) in accordance with the National Statement on Ethical Conduct in Human Research (2007, 2023): 197/23 for Reuse of expert nominated reference sites, non-reference sites and condition data for the ‘Priority Improvements to the Habitat Condition Assessment System’ project to develop HCAS v3. We acknowledge contributors to that data as listed on page 3 of Williams et al. (2023: CSIRO publication EP2023-1426; DOI: https://doi.org/10.25919/r12v-ya32).
A technical report series details methods and innovations involved in developing the HCAS version 3 series. For the latest publications see: https://research.csiro.au/biodiversity-knowledge/projects/hcas/, or contact us at hcas@csiro.au or geospatial@dcceew.gov.au.
We acknowledge other contributors to the development of HCAS including authors of the internationally published overarching framework for the HCAS method (Harwood et al., 2016), and subsequent incremental improvements through two trial implementations: HCAS v2.0 beta (Williams et al., 2020), HCAS v2.1 (Williams et al., 2021a), and pilot applications to ecosystem accounts: HCAS v2.2 (Williams et al., 2021a) and HCAS v2.3 (Williams et al., 2023b), and acknowledgments therein. Specifically, we acknowledge Dr Thomas D Harwood who developed the code that formed the foundation of HCAS v2.
Further details are provided in the accompanying "Habitat Condition Assessment System (HCAS) version 3.3: A guide to the 90-metre data collection" (publication EP2025-2979), to be released in 2026, which can be downloaded separately from CSIRO's publication repository.