Reviewing the use of proxies to value coastal and marine biodiversity protection: The Great Barrier Reef in Australia

Coastal and marine resources often require to be valued to assess management options and encourage sustainable policy-making. While numerous non-market valuation techniques are available, the complexity of biodiversity makes applications challenging. Typically, a small number of proxy assets (e.g. coral reefs) are used to represent more complex natural assets and processes in valuation exercises. While using proxies simplifies the assessment process, it can be challenging to interpret what values represent. We conduct a comprehensive review of the use of proxies to represent coral reef biodiversity in the Great Barrier Reef, Australia, spanning four decades (1983–2020) of literature. Studies are categorized based on the Total Economic Value and Ecosystem Services components they refer to, and the different approaches to the use of proxies. We identify that value estimates are sensitive to the type of proxy, and recommend habitat- or process-focused proxies over species-focused proxies as being more holistic and accurate. The most adequate proxies may, however, be considered on a case by case basis, depending on the policy question being addressed.