NbS Triple Win Toolkit: Biodiversity Indicators in Context 33 the role industrialisation and intensification of human activitieshas played. The most significant drivers of species loss are habitat destruction or degradation, overexploitation, pollution, climate change and invasive species. Without urgent action a further accelerationin global species extinction rates is expected, causing significant species loss and triggering wider impacts throughout ecosystems. Tackling biodiversity loss has rapidly become a global target. The CBD post-2020 biodiversity framework aims to stabilise and restore species’ conservation statuses, promoting the attainment of the Aichi Biodiversity Target “to improve the status of biodiversity by safeguarding ecosystems, species and genetic diversity.” The UN SDGs make specific reference to species conservation within wider aims to “halt biodiversity loss”, aiming to “protect and prevent the extinction of threatened species.” Monitoring the contribution of NbS towards improving species’ conservation statuses is crucial in assessing progress towards achieving these global targets. The proposed indicator quantifies the global reduction in threatened species’ extinction risk as a result of programme activities, based on the International Union for the Conservation of Nature (IUCN) Species Threat Abatement and Restoration (STAR) metric. The metric could be a valuable headline indicator, as it focuses solely on the impact of programme activities on threatened species, a key target in several global environmental goals. The spatially explicit nature of the metric facilitates efficient aggregation of impacts across projects to a portfolio level, and means that the metric can be reported in a range of ways – numerically, graphically and through mapping. The underlying method outlined by Mair et al. (2021)37 is highly detailed and has undergone extensive sensitivity analyses and peer review to limit and account for uncertainty. The separate calculation of threat abatement and habitat restoration components within the STAR methodology increases the applicability across NbS, or any programme of work where an aim is to reduce species’ pressures across a landscape, while the scaling of restoration scores to account for low habitat recovery rates ensures a realistic estimate of the positive contribution restoration efforts offer towards alleviating extinction risk. Proposed indicator The indicator quantifies the potential reduction in terrestrial species’ extinction risk as a result of programme activities, based on the programme area and the species’ threats it seeks to address. The STAR method provides an additive metric that can be applied at multiple spatial scales to determine the contribution of individual projects, NbS portfolios, or entire nations, to extinction risk reduction. STAR is divided into two components: the STAR threat abatement score (STARt) and the STAR habitat restoration score (STARr) that can be combined to determine the potential contribution that threat abatement and habitat restoration would offer towards reducing extinction risk of threatened species. Note that the STAR method is not prescriptive about the definition of habitat restoration, and therefore does not apply the SER definition as with the “Hectares under ecological restoration” proposed indicator, but quantifies the potential contribution of restoration activities towards reducing extinction risk based on the area of restorable habitat at a location relative to the global area of remaining habitat for a particular species. Projects will need to demonstrate that the proposed restoration activitieswill have a significant positive impact on the area of available habitat for threatened species. STARt is calculated using the number of threatened and near threatened species at a location (for example a grid cell, or project boundary), their conservation status (Near Threatened, Vulnerable, Endangered or Critically Endangered) and the proportion of theglobal available Area of Habitat (AOH) for each species present