Washington D.C. Office

Species Threat Abatement and Recovery (STAR) Metric

Cheetah Serengeti

What is the Species Threat Abatement and Recovery (STAR) Metric?

The STAR* measures the contribution that investments can make to reducing species extinction risk.It can help national and subnational governments, cities, civil society, the finance industry, investors and companies to target their investments and activities to achieve conservation outcomes and contribute to global policy aims.

Key features of the STAR:

  • A fully additive metric, from pixel to global, or across sites in a portfolio
  • Allows comparison across investment targets – a change in value in one place is directly comparable to a change somewhere else on the planet
  • Responsive at the pace of investors
  • Based on the IUCN Red List of Threatened Species – the global standard for documenting species’ conservation status 

How is the STAR calculated?

The STAR apportions the relative contribution of threats (pressures) to each threatened species’ extinction risk. For a particular site, land management unit, or administrative region (country or province), the STAR shows the potential for reducing extinction risk before investment activities start (ex-ante measure), or can measure the achieved impact of conservation interventions on extinction risk over time (ex-post measure).

The STAR scales larger or smaller according to:

  • The number and Red List category of threatened species present at a site or administrative region, and the proportion of their ranges occupied by the site. The larger the number of species, the greater the proportion of their ranges occupied by the site, and the more threatened they are, the larger the potential return
  • How much each kind of pressure affects those species. The greater the potential reduction in a pressure is, the greater the potential return
  • The effectiveness with which particular pressures are reduced by interventions

The STAR shows how interventions deliver reductions in pressure that can result in changes to the Red List Index (RLI), which is used as the biodiversity indicator for the Sustainable Development Goals, the Aichi Targets and the United Nations System for Environmental-Economic Accounting. The STAR responds to change faster than the Red List Index  and can be meaningfully applied at smaller scales. Positive changes in the STAR are clear evidence of progress generated by investment towards reducing extinction risk.

Using the STAR

The STAR shows ex-ante (potential) and ex-post (achieved) impacts of investments at a range of scales and over a range of timeframes. It has a range of potential uses, including:

  • Analysis and comparison of potential and achieved return on investment across a portfolio
  • Targeting interventions at particular sites and/or particular pressures
  • Tracking sectoral impacts on extinction risk, e.g. through commodity companies footprint
  • Developing and tracking global targets on slowing extinction risk, for instance for the post-2020 Aichi targets

*STAR was previously known as the Biodiversity Return on Investment Metric (BRIM).

For further details, and to receive future updates, please contact: brim@iucn.org 


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