Data Paper

IsoFresh: A global stable isotope database of freshwater food webs

¹ Centre de Recherche sur la Biodiversité et l'Environnement (CRBE), Université de Toulouse, CNRS, IRD, Toulouse INP, Université Toulouse 3–Paul Sabatier (UT3), Toulouse, France
² Fondation pour la Recherche sur la Biodiversité – Centre de Synthèse et d’Analyse sur la Biodiversité (FRB-CESAB), Montpellier, France
³ Conservation Science Partners, Inc., Truckee, CA, USA
⁴ German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
⁵ Department of Computer Science, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
⁶ Biology Department, Seattle University, Seattle, WA, United States
⁷ King County Water and Land Resources Division, Science and Technical Support Section, Seattle, Washington, USA
⁸ Scottish Centre for Ecology and the Natural Environment, School of Biodiversity, One Health and Veterinary Medicine, University of Glasgow, UK
⁹ Water@Leeds, School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
¹⁰ South African Institute for Aquatic Biodiversity (SAIAB), Makhanda, South Africa
¹¹ Te Kura Pūtaiao Koiora, Te Whare Wānanga o Waitaha | School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand
¹² Faculty of Geoscience and Environment, University of Lausanne, Lausanne, Switzerland
¹³ Área de Biodiversidad y Conservación, Departamento de Biología y Geología, Física y Química Inorgánica, Universidad Rey Juan Carlos, Móstoles, Madrid, Spain
¹⁴ DECOD, INRAE, IFREMER, L’Institut Agro, Rennes, France
¹⁵ Freshwater Habitat Section, National Centre for Effectiveness Science, Fisheries and Oceans Canada, Moncton, New Brunswick, Canada
¹⁶ Department of Biology, University of Oxford, Oxford, UK
¹⁷ School of Aquatic and Fishery Sciences, University of Washington, Seattle, Washington, 98105, USA

^* Corresponding authorS: stephanie.bouletreau@univ-tlse3.fr; julien.cucherousset@univ-tlse3.fr

Received: 7 March 2025
Accepted: 16 April 2025

Abstract

Ecologists seek to understand the ways that human activities are altering the structures and processes that support biodiversity and nature's contributions to people. Food web research at the interface of community and ecosystem ecology is promising in this regard. An industry of studies has utilized stable isotopes in recent decades to rapidly characterize energy and material transfer among organisms in freshwater food webs. Nevertheless, these efforts have been somewhat siloed and mainly locally-based, and lack of a centralized database has limited efforts to tackle questions about food web change using isotopes at a global scale. Here we present IsoFresh, a freshwater food web database that contains species-level carbon (δ¹³C) and nitrogen (δ¹⁵N) stable isotope values for 15343 organisms, representing 1001 food webs and including > 1600 fish species and associated potential prey, from 65 countries around the globe. Our hope is that IsoFresh is used to explore fundamental and applied food web questions, contributing new knowledge about global environmental change so that human societies can better conserve and manage freshwater ecosystems along desirable future trajectories.