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BioMetric: Terrestrial Biodiversity Tool for the NSW Property Vegetation Planning System

BioMetric is the biodiversity module in the Native Vegetation Assessment Tool (NVAT) package that facilitates preparation of Property Vegetation Plans (PVPs) under the NSW Native Vegetation Act 2003. BioMetric is used in conjunction with: a GIS tool that maps features of proposals; tools that assess threatened species, land and soil capability, salinity, water quality and invasive native scrub. This information is collated into a Property Vegetation Plan and stored in an administrative database called PADACS (PVPs, Agreements, Data and Customer Service).

This page contains supporting information for users of BioMetric.  It will be updated as new information becomes available.

General information

BioMetric is a tool for assessing terrestrial biodiversity at the scale of the patch, paddock or property - it is not a planning tool. It assesses:

  • losses of biodiversity from proposed clearing (including thinning)
  • gains in biodiversity from proposed offsets
  • gains in biodiversity from management actions proposed for incentives.

Neither BioMetric nor the Operational Manual (see below) deals with the assessment of private native forestry, clearing for routine agricultural management activities, continuation of existing farming activities, or clearing of regrowth. For information on these matters, see native vegetation management.

For additional information on BioMetric and the approach used to develop the assessment methodology and tool, refer to Gibbons et al. 2009. An operational method to assess impacts of land clearing on terrestrial biodiversity. Ecological Indicators. 9(1), 26-40.


BioMetric includes a process for assessing thinning. Refer to the BioMetric Operational Manual (see below) for guidance in undertaking thinning PVP assessments.

Invasive native scrub

BioMetric does not assess management of invasive native scrub, composed of invasive native species. Management of invasive native scrub is assessed by the separate invasive native scrub NVAT module. For more details, see the following information on the native vegetation website:

BioMetric operational manual and data sheets

Datasets for BioMetric assessments

The development of the BioMetric tool necessitated the development of three new underpinning datasets across the State of NSW:

  • vegetation types ("Overcleared vegetation types database")
  • vegetation condition benchmarks ("Vegetation benchmarks database")
  • "overcleared landscapes database".

Vegetation types

At a number of stages in the BioMetric assessment process, assessors must identify the vegetation types on the site, together with associated information.

Separate vegetation type classifications have been developed for each of the 13 Catchment Management Authority (CMA) areas created as part of the NSW Natural Resource Management Reform process. Most of the vegetation types comprise the original vegetation types (i.e. pre-clearing, or pre-1750) in each CMA area. However a small number of derived vegetation types are also listed, especially where the original vegetation type no longer exists or where the vegetation type occurs both naturally and as a derived community.

Each vegetation type is defined for field identification purposes on the basis of the following attributes, where relevant (these can be accessed via the ("Reference Data Help Files") button in BioMetric):

  • dominant canopy species
  • main associated species
  • landscape position
  • characteristic mid-storey species
  • characteristic groundcover species
  • other diagnostic features.

Additionally, each vegetation type is assigned to broader vegetation class/es and overarching vegetation formation/s (sensu Keith 2004). A per cent cleared estimate (rounded to nearest 5 per cent) is provided for each vegetation type in the relevant CMA area. Information to assist in the assessment of derived vegetation is also provided where relevant (see below for detail).

You can download current vegetation types for use in BioMetric below (containing percent cleared figures and field definitions for each vegetation type in each Catchment Management Authority (CMA) area).

The vegetation types dataset is going through a process of progressive refinement and improvement. First developed in 2004 (Interim vegetation types of NSW developed for the BioMetric Tool PDF - 160KB), these data were systematically revised during 2006 and 2007 in a three-step process. The following reports document the revision processes undertaken for the 13 CMAs (including Sydney Metro CMA). The approval and consultation process was completed in May 2008, and these revised data have now been incorporated into the data file above.

A major classification and assessment of plant communities in NSW is underway by John Benson of the Royal Botanic Gardens (Benson 2006a). The first region to be completed was the western plains (Benson et al. 2006b). This information has now been updated, and the South-western Slopes Bioregion classification has also been finalised (Benson 2008). When complete, this statewide classification will provide the first consistent approach to site-scale vegetation typing across the State. This work will progressively be adopted into the CMA vegetation types classifications as it is completed. Note that a review process to incorporate data from Benson (2008) into the vegetation types dataset is scheduled for 2011.

Derived vegetation communities

Some of the vegetation types listed in BioMetric are derived or secondary vegetation communities. Derived vegetation communities are communities that have changed to an alternative stable state (sensu Westoby et al. 1989) as a consequence of management practices following European settlement. In practice, this often means that one or more structural components of the vegetation has been entirely removed or severely reduced (e.g. over-storey of grassy woodland), or has developed where it was previously absent (e.g. shrubby mid-storey in an open woodland system), in derived communities. Derived communities differ from modified natural communities in that derived communities are unable to revert to their pre-European state (i.e. community structure and/or composition) in the short to medium term following the simple removal (or reintroduction) of the disturbance pressures impacting upon them. Derived communities usually require significant management intervention to shift them out of their present state and a return to their original state may not be realistically achievable for some derived communities. Note, this working definition was developed for and used in the process of identifying derived vegetation types in each CMA, as identified in the Vegetation types dataset (above).

In the BioMetric assessment process, derived vegetation is assessed against the corresponding original vegetation type/s, not against the derived type/s. Consequently, benchmarks for the original type/s that were present should be used for assessing derived communities.

When assessing derived communities, the selection of vegetation type for the original community should be based on the informed judgement of the assessor, taking into consideration the remaining species composition, patterns of surrounding vegetation, landscapes position, soil type, and historical land management practices. The vegetation types classifications in BioMetric (and provided above) include, where possible, an indication of the original vegetation type/s for each derived vegetation type. Note that some vegetation types that are known to be derived in some circumstances may also occur within the same CMA as an original community. Where available, such information is also included in the vegetation types classification for each CMA.

Note, these rules for assessing derived vegetation communities apply to BioMetric. Rules for assessing derived communities may be different in other NVAT tools. Additional information to assist with the assessment of derived vegetation is provided in Section of the BioMetric Operational Manual (see above).

Vegetation condition benchmarks

Benchmarks are quantitative measures of the range of variability in condition in vegetation with relatively little evidence of alteration, disturbance or modification by humans since European settlement. Vegetation with relatively little evidence of modification generally has minimal timber harvesting (few stumps, coppicing, cut logs), minimal firewood collection, minimal exotic weed cover, minimal grazing and trampling by introduced herbivores or over abundant herbivores, minimal soil disturbance, minimal canopy dieback, no evidence of recent fire or flood, not subject to high frequency burning, and positive evidence of recruitment of native species.

Vegetation condition benchmarks are described for a suite of condition variables by vegetation type at the scale of the stand or patch. Benchmarks are used in BioMetric as yardsticks against which to assess the current and predicted future condition of native vegetation for clearing, offset and incentive proposals. Each condition variable is allocated a score from 0-3 (0=low, 1=moderate, 2=high, 3=very high) based on the difference between its measured value and its benchmark. This scoring system is explained in the BioMetric Operational Manual (Version 3.1 - updated February 2011) (PDF - 6.0 MB).

Benchmarks are predominantly available by vegetation class (sensu Keith 2004) for the 10 vegetation condition variables used to calculate Site Value (= condition at the stand or patch-scale) in the biodiversity score in BioMetric. Each vegetation class encompasses one to many vegetation types within each CMA area.

The vegetation condition benchmark dataset (PDF - 145 KB) was first developed using an expert workshop approach conducted during 2005. These data subsequently underwent a minor review (PDF 1.9MB) to correct identified errors during 2006. A comprehensive revision of these data will be required following completion of the scheduled review of the vegetation types database in 2011 (see above). We are also continuing to collate benchmark data for individual vegetation types as this information becomes available.

Information for calculating stem density benchmarks (PDF - 3 MB) of native tree and shrub species and vegetation communities was investigated by Anne Kerle for potential use in the assessment of thinning PVP proposals. However, very few stem density benchmarks are presently available, and assessment officers are encouraged to continue collecting their own reference sites stem density benchmarks (refer to BioMetric Operational Manual, above).

'Overcleared' landscapes

In BioMetric, clearing is not allowed in ecosystems (Mitchell Landscapes) that are more than 70 per cent cleared and are not in low condition.  The ecosystem classification used for this purpose is Mitchell (2002), which is mapped at 1:250,000 scale and includes ecosystem (Landscape) descriptions that can be used by assessors in the field to overcome the scale limitations of the mapped data (Mitchell 2003).

The spreadsheet available below lists the percent cleared estimate for each Mitchell Landscape type in each CMA area. To obtain these estimates, the NSW Landscapes coverage (Mitchell 2002) was intersected with a presence/absence layer of native vegetation in NSW. This presence/absence layer was an updated version of the layer developed by Pressey et al. (2000), called "SCMP Presence/Absence Vegetation" (NSW National Parks and Wildlife Service 2002).

This dataset is going through a process of progressive refinement and improvement. In 2006, the NSW vegetation presence/absence mask was updated (Keith and Simpson 2006). This new mask was subsequently intersected with the Mitchell Landscapes layer to produce revised per cent cleared estimates for each Mitchell Landscape. These clearing estimates were subsequently reviewed by regional CMA and OEH (formerly DECC) vegetation experts for those Mitchell Landscapes that contain significant amounts of native grassland (PDF - 1.3 MB) and subsequently for all remaining CMAs (PDF - 827 KB). In 2008, the Mitchell Landscapes linework was systematically reviewed and revised where necessary, at 1:100 000 scale (Mitchell Landscapes v3).

OEH projects that may be used to further refine the data underpinning the 'Overcleared landscapes database' include:

  • the next iteration of the Statewide Landcover and Trees Study (SLATS) vegetation extent map for NSW (for woody vegetation)
  • the next iteration of the NSW vegetation presence/absence mask is under development (primarily includes woody vegetation)
  • an assessment of the native grasslands of NSW (extent and condition), that will further improve the vegetation presence/absence mask
  • It is expected that the "Overcleared" landscapes data will next be reviewed, using these new data inputs, during 2020/11.

To download a copy of the Mitchell Landscapes GIS layer, please visit the OEH data download site.

EOAM and Assessment protocols

The NV Regulation sets out an Environmental Outcomes Assessment Methodology (EOAM) that must be used to assess whether clearing proposals improve or maintain environmental outcomes. The EOAM is applied using the Native Vegetation Assessment Tools (NVAT, including BioMetric).  Use this link to access the Biodiversity Assessment section of the EOAM.

The Minister has approved two assessment protocols that have been developed under clause 27(3)(b) and clause 27(3A)(b) of the NV Regulation 2005 for where a minor variation is made to the Environmental Outcomes Assessment Methodology: 

An accredited expert can use these two protocols to make an assessment that the proposed clearing will improve or maintain environmental outcomes and will have additional conservation benefits on a landscape scale.

Note, these protocols will be reviewed following the 2007-2010 review of Chapter 5 of the EOAM, comprising the assessment methodologies applied using BioMetric and the Threatened Species Tool.

Related links and documents

View a list of Management Actions 

Relevant references

Benson JS. 2008. New South Wales Vegetation Classification and Assessment: Part 2 Plant communities of the NSW South-western Slope Bioregion and update of NSW Western Plains plant communitieis, Version 2 of the NSWVCA database. Cunninghamia. 10(4), 599-673.

Benson JS. 2006a. New South Wales Vegetation Classification and Assessment: Introduction – the classification, database, assessment of protected areas and threat status of plant communities. Cunninghamia. 9(3), 331-382.

Benson JS, Allen CB, Togher C, Lemmon J. 2006b. New South Wales Vegetation Classification and Assessment: Part 1 Plant communities of the NSW Western Plains. Cunninghamia. 9(3), 383-450.

Gibbons P, Briggs SV, Ayers DA, Doyle S, Seddon J, McElhinny C, Jones N, Sims R, Doody JS. 2008. Rapidly quanitfying reference conditions in modified landscapes. Biological conservation, 141,2483-2493.

Keith D. 2004. Ocean shores to desert dunes: the native vegetation of New South Wales and the ACT. NSW Department of Environment and Conservation, Hurstville.

Kerle JA. 2005. Collation and review of stem density data and thinning prescriptions for the vegetation communities of New South Wales. Report commissioned by DEC (PDF - 2.9MB)

McElhinny C. 2002. Forest and woodland structure as an index of biodiversity: a review (report commissioned by the NPWS) (PDF - 315KB) Now published as McElhinny C, Gibbons P, Brack C, Bauhus J. 2006. Fauna-habitat relationships: a basis for identifying key stand structural attributes in temperate Australian eucalypt forests and woodlands. Pac. Cons. Biol. 12, 89-110.

Mitchell PB. 2002.  NSW ecosystems study: background and methodology. Unpublished report to the NSW National Parks and Wildlife Service, Hurstville.

Mitchell PB. 2003.  NSW ecosystems database mapping unit descriptions. Unpublished report to the NSW National Parks and Wildlife Service, Hurstville.

NSW National Parks and Wildlife Service. 2002. SCMP Presence/Absence Vegetation. Metadata Statement and GIS layer.

Pressey RL, Hagar, TC, Ryan KM, Schwarz J, Wall S, Ferrier S, Creaser PM. 2000. Using abiotic data for conservation assessments over extensive regions: quantitative methods applied across New South Wales, Australia.  Biological Conservation. 96, 55-82.

Westoby M, Walker B, Noy-Meir I. 1989. Opportunistic management for rangelands not at equilibrium. Journal of Range Management. 42, 266-274.

Frequently asked questions

  • Frequently-asked questions about BioMetric
  • For all other questions regarding BioMetric, its underpinning data, biodiversity issues relevant to the Native Vegetation Act 2003 and other issues related to biodiversity and vegetation condition assessment metrics, please email BioMetric Help.
  • Biometric is not available as a stand-alone tool.

Help us to revise the BioMetric datasets

If you have data or information that you would like to make available for future revisions of the BioMetric assessment methodology or datasets, please email BioMetric Help.

Page last updated: 25 November 2013