Research Article

Are we heading towards a global decrease in coregonine catches?

¹ University of Savoie-Mont Blanc, INRAE, UMR CARRTEL, Thonon les Bains, France
² University of Savoie-Mont Blanc, INRAE, UMR CARRTEL, Thonon les Bains, France − Pole R&D ECLA Ecosystèmes Lacustres, France
³ Institute of Fisheries Science, National Taiwan University, Taiwan ROC
⁴ Fisheries Research Station Baden-Württemberg, Argenweg 50/1, 88085 Langenargen, Germany
⁵ University of Savoie-Mont Blanc, INRAE, UMR CARRTEL, Thonon les Bains, France − Scimabio Interface, 74200 Thonon-les-Bains, France
⁶ Fisheries Research Station Baden-Württemberg, Argenweg 50/1, 88085 Langenargen, Germany − University of Constance, Institute for Limnology, Konstanz, Germany
⁷ U.S. Geological Survey Great Lakes Science Center, Ann Arbor, Michigan, United States
⁸ Swedish University of Agricultural Sciences, Department of Aquatic Resources, Institute of Freshwater Research, Drottningholm, Sweden
⁹ Institute of Oceanography, National Taiwan University, Taipei 10617, Taiwan
¹⁰ Freshwater Institute, Fisheries and Oceans Canada, Winnipeg, Manitoba, Canada
¹¹ U.S. Fish and Wildlife Service, La Crosse Fish and Wildlife Conservation Office, Onalaska, Wisconsin, USA
¹² Centre for Limnology, Chair of Hydrobiology and Fishery, Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Tartu, Estonia
¹³ Institute of Biology, Chair of vertebrate zoology and ecology, Irkutsk State University, Irkutsk, Russia

^* Corresponding Author: orlane.anneville@inrae.fr

Received: 5 December 2024
Accepted: 14 February 2025

Abstract

Coregonines have specific ecological needs, making them potentially very vulnerable to changes in lake conditions. A contemporary concern is that many lakes worldwide are experiencing environmental changes due to anthropogenic pressure and climate warming. Here, we compiled long-term data of coregonine catches from 27 lakes from three continents in the northern hemisphere. Declines in catch were observed in 67% of the lakes during the first two decades of the 21^st century, with a significant trend (p-value<0.05) in 44% of the cases. An analysis to determine whether trends are globally linked to environmental conditions and specific lake attributes was carried out on 26 lakes for the period 2000–2019. Several local declines in catches had already been documented in the literature and are likely to be due to local forcing such as nutrients, species invasions and changes in fishing practices. Nevertheless, on a global scale, our results indicate that lakes, which exhibited a significant decrease in catch were larger and more nutrient-poor than other lakes. The rate of change in catches appeared to be related to the trophic state of the lake. The specific effect of warming is difficult to determine during the studied period. When warming occurred outside the period of egg incubation, decreasing trends were more frequently observed in nutrient-poor than in mesotrophic lakes. In conclusion, our findings suggest that achieving oligo- or ultraoligotrophic conditions, as required in developed countries to control phytoplankton blooms and enhance water quality, could pose significant challenges for future management of coregonine fisheries.