Essential biodiversity variables for mapping and monitoring species populations

Perspective https://doi.org/10.1038/s41559-019-0826-1 Essential biodiversity variables for mapping and monitoring species populations Walter Jetz 1*, Melodie A. McGeoch 2, Robert Guralnick 3, Simon Ferrier4, Jan Beck5, Mark J. Costello 6, Miguel Fernandez7,8,9, Gary N. Geller10, Petr Keil 11, Cory Merow1, Carsten Meyer 11,12, Frank E. Muller-Karger 13, Henrique M. Pereira 11,14,15, Eugenie C. Regan16, Dirk S. Schmeller17,18 and Eren Turak19,20 Species distributions and abundances are undergoing rapid changes worldwide. This highlights the significance of reliable, integrated information for guiding and assessing actions and policies aimed at managing and sustaining the many functions and benefits of species. Here we synthesize the types of data and approaches that are required to achieve such an integration and conceptualize ‘essential biodiversity variables’ (EBVs) for a unified global capture of species populations in space and time. The inherent heterogeneity and sparseness of raw biodiversity data are overcome by the use of models and remotely sensed covariates to inform predictions that are contiguous in space and time and global in extent. We define the species population EBVs as a space–time–species–gram (cube) that simultaneously addresses the distribution or abundance of multiple species, with its resolution adjusted to represent available evidence and acceptable levels of uncertainty. This essential information enables the monitoring of single or aggregate spatial or taxonomic units at scales relevant to research and decision-making. When combined with ancillary environmental or species data, this fundamental species population information directly underpins a range of biodiversity and ecosystem function indicators. The unified concept we present links disparate data to downstream uses and informs a vision for species population monitoring in which data collection is closely integrated with models and infrastructure to support effective biodiversity assessment. B iodiversity and the many ecosystem functions and services it underpins are undergoing significant and often rapid changes worldwide1. A range of global initiatives and policy frameworks, including the Convention on Biological Diversity (CBD) and Sustainable Development Goals (SDGs), have aimed to reduce this change and to halt the loss of biodiversity, with limited progress to date2. Appropriately gauging the impact of such policies or the progress toward international biodiversity goals has a key requirement: the availability of information on the status and trends of biodiversity in a form that is easily understood, timely, scientifically rigorous, standardized, relevant, global and representative of species populations across taxa and regions over time. Such information is particularly crucial in assessments, such as those carried out by the Intergovernmental Science–Policy Platform on Biodiversity and Ecosystem Services (IPBES)3, and is needed to construct ‘indicators’, which are aggregate measures that often address specific conservation targets4,5. Underpinning such metrics are core, essential measurements known as EBVs, which capture key constituent components of biodiversity change6,7, akin and complementary to the ‘essential climate variables’ supporting climate change assessment and policy8. Facilitated by the Group on Earth Observations Biodiversity Observation Network (GEO BON, http://geobon.org) and related efforts, the biodiversity science and observation community is now engaging in an effort to conceptualize and formulate these essential biodiversity components to enable more focused, integrated, and effective biodiversity monitoring in support of assessment and policy within a unified framework. This study represents the formal outcome of a process undertaken from 2015 through 2018 by the founding members of the GEO BON Species Populations Working Group9, which includes the authors of this Perspective, charged with providing the formal definitions, conceptualizations and recommendations addressing species distribution and abundance EBVs. Changes in species distribution and abundance affect all biodiversity facets10, including the loss of potentially significant traits and functions1,11 and associated ecosystem consequences12,13. Patterns of spatial distribution and changes to these patterns inform us about the commonness, rarity and potential extinction risk for species14–16, determine the national and regional stewardship of species and are key to ensuring effective monitoring17, protection18,19 and population Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA. 2School of Biological Sciences, Monash University, Melbourne, Victoria, Australia. Florida Museum of Natural History, University of Florida at Gainesville, Gainesville, FL, USA. 4CSIRO Land and Water, Canberra, New South Wales, Australia. 5Museum of Natural History, University of Colorado Boulder, Boulder, CO, USA. 6Institute of Marine Science, University of Auckland, Auckland, New Zealand. 7NatureServe, Arlington, VA, USA. 8Universidad Mayor de San Andrés, Instituto de Ecología, La Paz, Bolivia. 9Smithsonian-Mason School of Conservation and Department of Environmental Science and Policy, George Mason University, Fairfax, VA, USA. 10NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA. 11German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany. 12 Faculty of Biosciences, Pharmacy and Psychology, University of Leipzig, Leipzig, Germany. 13College of Marine Science, University of South Florida, Saint Petersburg, FL, USA. 14Institute of Biology, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany. 15CiBiO/InBIO — Research Network in Biodiversity and Genetic Resources, Campus Agrário de Vairão, Universidade do Porto, Vairão, Portugal. 16UN Environment World Conservation Monitoring Centre, Cambridge, UK. 17Helmholtz Centre for Environmental Research — UFZ, Department of Conservation Biology, Permoserstrasse, Leipzig, Germany. 18 EcoLab, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France. 19NSW Office of Environment & Heritage, Sydney, New South Wales, Australia. 20 Australian Museum, Sydney, New South Wales, Australia. *e-mail: 1 3 Nature Ecology & Evolution | VOL 3 | APRIL 2019 | 539–551 | www.nature.com/natecolevol 539 Perspective NaTurE Ecology & EVoluTion connectivity20 of species. Species-conservation goals often are particularly relevant to conservation legislation, and species population information used in tracking progress for CBD 2020 Targets 5, 11, 12 and 19 and SDG Goals 14 and 15, among others. When linked to data on surrounding conditions, occurrence information may provide insight into the realized environmental niche spaces of species21, which is key to capturing future consequences of global change22,23. Finally, species distribution and abundance have a range of other applications in scien (...truncated)