Can size distributions of European lake fish communities be predicted by trophic positions of their fish species?. Issue 7 (11th July 2022)

• Record Type: Journal Article
• Authors: van Dorst, Renee M.; Argillier, Christine; Brucet, Sandra; Holmgren, Kerstin; Volta, Pietro; Winfield, Ian J.; Mehner, Thomas
• Is Part Of: Ecology and evolution. Volume 12:Issue 7(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-07-11
• Subjects: body size -- community size spectrum -- ecological interactions -- fish -- predator–prey interactions -- trophic level; Ecology -- Periodicals; Evolution -- Periodicals; 577.05
• DOI: 10.1002/ece3.9087
• Languages: English
• ISSNs: 2045-7758

Abstract

Abstract: An organism's body size plays an important role in ecological interactions such as predator–prey relationships. As predators are typically larger than their prey, this often leads to a strong positive relationship between body size and trophic position in aquatic ecosystems. The distribution of body sizes in a community can thus be an indicator of the strengths of predator–prey interactions. The aim of this study was to gain more insight into the relationship between fish body size distribution and trophic position in a wide range of European lakes. We used quantile regression to examine the relationship between fish species' trophic position and their log‐transformed maximum body mass for 48 fish species found in 235 European lakes. Subsequently, we examined whether the slopes of the continuous community size distributions, estimated by maximum likelihood, were predicted by trophic position, predator–prey mass ratio (PPMR), or abundance (number per unit effort) of fish communities in these lakes. We found a positive linear relationship between species' maximum body mass and average trophic position in fishes only for the 75% quantile, contrasting our expectation that species' trophic position systematically increases with maximum body mass for fish species in European lakes. Consequently, the size spectrum slope was not related to the average community trophic position, but there were negative effects of community PPMR and total fish abundance on the size spectrum slope. We conclude that predator–prey interactions likely do not contribute strongly to shaping community size distributions in these lakes. Abstract : We aimed to gain more insight in the relationship between fish body size distribution and trophic position in a wide range of European lakes. We had some unexpected results as a strong positive relationship between fish species trophic position and species‐specific maximum body mass is not supported for the fish species inhabiting European lakes. Consequently, the size spectrum slope was not related to the average fish community trophic position in our lakes.