Ubiquitous trophic niche partitioning drives species coexistence and biomass on coral reefs
Year: 2026
Type: preprint
Abstract: Coral reefs support an extraordinary diversity and biomass of fishes. However, whether species coexist through fine-scale niche partitioning, and whether this impacts ecosystem functioning, remain unresolved. We combined DNA metabarcoding and stable isotope analysis to reconstruct a high-resolution food web and quantify the trophic niches of 2,060 reef fishes across 261 species. We observed extreme trophic partitioning: species pairs diverged by a median of 93% (DNA metabarcoding) and 86% (stable isotopes), consistently overlapping far less than expected by chance. Further, communities with greater trophic complementarity supported higher standing-stock biomass, particularly at high species richness. Our results confirm limiting similarity and trophic complementarity as the driving forces of coexistence and ecosystem functioning in the ocean’s most diverse ecological community.
Institutions: Smithsonian Institution, Centre National de la Recherche Scientifique, National Museum of Natural History, Université de Perpignan, École Pratique des Hautes Études, Centre de Recherches Insulaires et Observatoire de l'Environnement, University of Texas at Austin Marine Science Institute, The University of Texas at Austin, University of Lisbon, University of California San Diego, Joint Research Centre, Université Paris Sciences et Lettres, Ifremer, Santé et Services des Ecosytèmes Polynésiens
Language: English
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
SDG: Life below water
Open Access status: green
OpenAlex ID: W7214071786