Abstract

AimOur aim was to document geographical patterns of variation in the body-size structure of European lake fish assemblages along abiotic gradients, and any differences in fish assemblage structure. We hypothesized that patterns in the body-size structure of entire lake fish assemblages are primarily temperature driven and consistent with the dominant pattern of the temperature-size rule, which suggests a decrease in adult body size with increasing developmental temperature for many ectothermic species.Location356 European lakes.MethodsVariation in the body-size structure of fish assemblages was explored on a continental scale along gradients of temperature, morphometry, productivity and fish assemblage structure for 356 European lakes. The mean fish assemblage body-size and individual body-size distributions were selected as size metrics. Separate analyses were conducted for lakes located within five ecoregion subsets (Borealic Uplands/Tundra, FennoScandian Shield, Central Plains, Western Plains and Western Highlands) and for lakes with different functional fish classifications (cold-, cool- and warmwater fish assemblages).ResultsGeographical patterns of variation in the body-size structure of European lake fish assemblages could be clearly discerned along a temperature gradient for both the continental dataset (356 lakes) and the smaller geographical (ecoregion) subsets. We found systematic changes in fish assemblage body-size structure across temperature gradients in correspondence with the dominant thermal fish guild. The majority of the lakes, mainly located in the warmer European lowlands, were dominated by eurythermic cool- and warmwater fish assemblages, with smaller sized individuals characterized by linear individual body-size distributions. Lakes located in colder regions and dominated by stenothermic coldwater salmonids with larger sized individuals were characterized by unimodal or bimodal size distributions. The mean body size of cold-, cool- and warmwater fish assemblages changed uniformly along the temperature gradient.Main conclusionsPatterns of variation in the body-size structure of European lake fish assemblages are consistent with the temperature-size rule. Temperature modifies fish assemblage size structure uniformly within the thermal fish guilds and in different ecoregions. Furthermore, our results indicate an increasing predictive power of temperature to explain variability in body-size structure when moving from warmer to colder geographical regions.

Keywords

Body size; European lakes; freshwater fish; functional classification; individual body-size distribution; macroecology; multimesh gillnet; temperature gradient; temperature-size rule; thermal guild

Published in

Journal of Biogeography
2014, Volume: 41, number: 12, pages: 2221-2233

SLU Authors

• Holmgren, Kerstin

  • Department of Aquatic Resources (SLU Aqua), Swedish University of Agricultural Sciences
    

Associated SLU-program

Lakes and watercourses
Use of FOMA data


Sustainable Development Goals

Conserve and sustainably use the oceans, seas and marine resources for sustainable development


UKÄ Subject classification

Ecology


Publication identifier

DOI: https://doi.org/10.1111/jbi.12366

Permanent link to this page (URI)

https://res.slu.se/id/publ/63055