Methods for mapping areas important for biodiversity

The project found that significant work is already underway across Australia to identify areas important for biodiversity.

Australian areas important for biodiversity that are currently mapped using international (e.g. World Heritage Areas) and national (Threatened Species Priority Places) methods.

Many states, territories and non-government organisations already use well-developed methods to guide conservation planning. While these approaches vary, many share a similar scientific foundation, particularly the use of irreplaceability mapping.

Key findings include:

• Many Australian jurisdictions and conservation organisations are already using methods to identify areas important for biodiversity
• Most jurisdictions and surveyed non-government organisations use irreplaceability mapping, either through existing tools or in-house decision-support approaches
• Existing methods are often based on contemporary science, collaboration and the best available data for each state or territory
• While the methods are generally well aligned, differences in datasets and mapping approaches can create inconsistencies, particularly along state and territory borders
• A nationally harmonised approach could help smooth these boundary issues while still recognising the value of state and territory methods.

These findings show that Australia does not need to start from scratch. A national approach can build on the strong work already being done across jurisdictions and conservation organisations.

The project reviewed internationally recognised methods for identifying areas important for biodiversity.

These included:

• Key Biodiversity Area method
• KBA Criterion E – irreplaceability through quantitative analysis
• Biodiversity hotspots
• Outstanding Universal Value
• Ramsar sites.

Each method was assessed against four criteria:

1. Fit-for-purpose – whether the approach is feasible, compatible and responsive.
2. Inclusiveness – whether it can identify areas that represent genetic, species and ecosystem diversity.
3. Persistence – whether it considers the long-term survival of species and other biodiversity values.
4. Uniqueness – whether it can identify places with rare or distinctive species or ecosystems.

The review found that KBA Criteria A–D, KBA Criterion E – irreplaceability, and Outstanding Universal Value performed well overall. However, KBA Criterion E – irreplaceability performed strongly across all assessment criteria and is aligned with already used methods by jurisdictions and NGOs.

The final report recommends using irreplaceability mapping as a nationally consistent way to identify areas important for biodiversity in Australia.

In simple terms, this method helps show which places are hardest to replace, including places where important species, habitats or ecosystems cannot easily be protected somewhere else.

Many governments and conservation organisations already use this kind of mapping, and it can draw on existing biodiversity data such as vegetation, habitat and threatened species records.

The report also found that state and territory approaches are valuable and should help shape any national method. However, because jurisdictions often use different datasets and mapping approaches, important biodiversity areas can appear to stop at state borders, even when the natural values continue across them.

A harmonised national approach would help smooth out these differences, while still respecting the work already done by states and territories. This would ensure mapped areas important for biodiversity reflect ecological values, rather than administrative boundaries.

Recommended steps for developing a nationally consistent approach to identifying areas important for biodiversity. The process starts with national irreplaceability mapping, then brings in state and territory knowledge to create a harmonised framework that can be updated over time.

This project provides evidence to help governments and conservation organisations make clearer, more consistent decisions about where conservation effort could deliver the greatest biodiversity benefit.

The findings can support:

• planning for Australia’s 30-by-30 target
• identifying areas important for threatened species and ecosystems
• improving consistency between national, state and territory biodiversity mapping
• aligning Australian approaches with global biodiversity reporting requirements
• guiding future protected-area planning
• considering ecological representation and connectivity when expanding protected and conserved areas
• avoiding duplication by building on methods already used by states, territories and conservation organisations.

The research provides a foundation for future work to identify and compare important biodiversity areas across Australia in a consistent and practical way.