Advances in spatial biodiversity science and nationally available data have enabled the development of indicators that report on biodiversity outcomes, account for uneven global biodiversity between countries, and provide direct planning support. We urge their inclusion in the post-2020 global biodiversity framework.
Fig. 1: Measuring the transboundary nature of area-based biodiversity conservation. a, Distribution and protection of the zebra duiker (Cephalophus zebra), a rainforest specialist threatened by habitat loss (https://mol.org/species/protect/Cephalophus_zebra). The map shows global, habitat-suitable range by country, with Liberia holding the greatest portion (stewardship), and the variation in assumed national range portions protected. Basic formulas suggest 48% of global range as adequate conservation area representation for this species. b, SPI values by country (orange) derived from the individual Species Protection Scores (SPS) for the zebra duiker (cyan) and all assessed species (violin plots) in relation to protected area coverage (green). The SPS reflects the percentage of area representation target achieved within a country for a given species. Across assessed species, a country’s SPI is given as the average SPS, weighted by their respective stewardship (country-endemic species weigh most). SPI values range from 0 and 100, where a value of 50 means that on average species are half-way to sufficient representation in conservation areas. Depending on how effectively conservation areas represent species, national SPI scores are strongly or only slightly larger than the percentage of national area protected. Violin plots show variation of SPS values within and among countries for all assessed species (n = count of in-country species included). In this example, the duiker range portion protected in Liberia is below the adequacy target, resulting in a suboptimal SPS value (8%/48% = 16.7). See Supplementary Information for data calculations and other details and note that the indicator can be supplemented or directly calculated with nationally held data.
