One-quarter of freshwater fauna threatened with extinction

Authors

Catherine A. Sayer, IUCN (International Union for Conservation of Nature), Cambridge, UK. catherine.sayer@iucn.org.
Eresha Fernando, IUCN (International Union for Conservation of Nature), Cambridge, UK.
Randall R. Jimenez, IUCN (International Union for Conservation of Nature), San Jose, Costa Rica.
Nicholas B. Macfarlane, IUCN (International Union for Conservation of Nature), Washington, DC, USA.
Giovanni Rapacciuolo, Elimia, San Diego, CA, USA.
Monika Böhm, Global Center for Species Survival, Indianapolis Zoo, Indianapolis, IN, USA.
Thomas M. Brooks, IUCN (International Union for Conservation of Nature), Gland, Switzerland.
Topiltzin Contreras-MacBeath, Laboratorio de Ictiología, Centro de Investigaciones Biológicas, Universidad Autónoma del Estado de Morelos, Cuernavaca, México.
Neil A. Cox, IUCN (International Union for Conservation of Nature), Washington, DC, USA.
Ian Harrison, Free Flowing Rivers Laboratory, Northern Arizona University, Flagstaff, AZ, USA.
Michael Hoffmann, Zoological Society of London, London, UK.
Richard Jenkins, IUCN (International Union for Conservation of Nature), Cambridge, UK.
Kevin G. Smith, IUCN (International Union for Conservation of Nature), Cambridge, UK.
Jean-Christophe Vié, Fondation Franklinia, Geneva, Switzerland.
John C. Abbott, The University of Alabama, Tuscaloosa, AL, USA.
David J. Allen, IUCN (International Union for Conservation of Nature), Cambridge, UK.
Gerald R. Allen, Western Australian Museum, Perth, Western Australia, Australia.
Violeta Barrios, Sahara Conservation, Saint Maur des Fossés, France.
Jean-Pierre Boudot, University of Nancy/CNRS, Vandoeuvre-lès-Nancy, France.
Savrina F. Carrizo, Zoo and Aquarium Association Australasia, Sydney, New South Wales, Australia.
Patricia Charvet, Federal University of Ceará, Fortaleza, Brazil.
Viola Clausnitzer, Senckenberg, Görlitz, Germany.
Leonardo Congiu, University of Padova, Padova, Italy.
Keith A. Crandall, George Washington University, Washington, DC, USA.
Neil Cumberlidge, Northern Michigan University, Marquette, MI, USA.
Annabelle Cuttelod, Independent researcher, Pully, Switzerland.
James Dalton, IUCN (International Union for Conservation of Nature), Gland, Switzerland.
Adam G. Daniels, Independent researcher, Cambridge, UK.
Sammy De Grave, Oxford University Museum of Natural History, Oxford, UK.
Geert De Knijf, Research Institute for Nature and Forest (INBO), Brussels, Belgium.
Klaas-Douwe B. Dijkstra, Naturalis Biodiversity Center, Leiden, The Netherlands.
Rory A. Dow, Naturalis Biodiversity Center, Leiden, The Netherlands.

Document Type

Journal Article

Publication Date

1-8-2025

Journal

Nature

DOI

10.1038/s41586-024-08375-z

Abstract

Freshwater ecosystems are highly biodiverse and important for livelihoods and economic development, but are under substantial stress. To date, comprehensive global assessments of extinction risk have not included any speciose groups primarily living in freshwaters. Consequently, data from predominantly terrestrial tetrapods are used to guide environmental policy and conservation prioritization, whereas recent proposals for target setting in freshwaters use abiotic factors. However, there is evidence that such data are insufficient to represent the needs of freshwater species and achieve biodiversity goals. Here we present the results of a multi-taxon global freshwater fauna assessment for The IUCN Red List of Threatened Species covering 23,496 decapod crustaceans, fishes and odonates, finding that one-quarter are threatened with extinction. Prevalent threats include pollution, dams and water extraction, agriculture and invasive species, with overharvesting also driving extinctions. We also examined the degree of surrogacy of both threatened tetrapods and freshwater abiotic factors (water stress and nitrogen) for threatened freshwater species. Threatened tetrapods are good surrogates when prioritizing sites to maximize rarity-weighted richness, but poorer when prioritizing based on the most range-restricted species. However, they are much better surrogates than abiotic factors, which perform worse than random. Thus, although global priority regions identified for tetrapod conservation are broadly reflective of those for freshwater faunas, given differences in key threats and habitats, meeting the needs of tetrapods cannot be assumed sufficient to conserve freshwater species at local scales.

APA Citation

Sayer, Catherine A.; Fernando, Eresha; Jimenez, Randall R.; Macfarlane, Nicholas B.; Rapacciuolo, Giovanni; Böhm, Monika; Brooks, Thomas M.; Contreras-MacBeath, Topiltzin; Cox, Neil A.; Harrison, Ian; Hoffmann, Michael; Jenkins, Richard; Smith, Kevin G.; Vié, Jean-Christophe; Abbott, John C.; Allen, David J.; Allen, Gerald R.; Barrios, Violeta; Boudot, Jean-Pierre; Carrizo, Savrina F.; Charvet, Patricia; Clausnitzer, Viola; Congiu, Leonardo; Crandall, Keith A.; Cumberlidge, Neil; Cuttelod, Annabelle; Dalton, James; Daniels, Adam G.; De Grave, Sammy; De Knijf, Geert; Dijkstra, Klaas-Douwe B.; and Dow, Rory A., "One-quarter of freshwater fauna threatened with extinction" (2025). GW Authored Works. Paper 6394.
https://hsrc.himmelfarb.gwu.edu/gwhpubs/6394

Department

Biostatistics and Bioinformatics