| Abstract | We studied fish size structure by using mean size, size diversity, and the slope of linear size spectra of six common European fish species along large-scale environmental gradients. We further analyzed the response of these three size metrics to environmental variables and to density-dependent effects, i.e., relative estimates of abundance (catch per unit effort, CPUE). We found differences in the strength of main predictors of size structure between the six species, but the direction of the response was relatively similar and consistent for most of the size metrics. Mean body size was negatively related to temperature for perch (Perca fluviatilis), roach (Rutilus rutilus), and ruffe (Gymnocephalus cernuus). Lake productivity (expressed as total phosphorus concentration) and lake depth were also predictors of size structure for four of six species. Moreover, we found a strong density dependence of size structure for all species, resulting in lower mean body size and size diversity and steeper size spectra slopes when density dependence increases. This suggests that density dependence is a key driver of fish size structure. |
| Text | 366800 2015 10.1139/cjfas 2014 0508 Density dependent effects Size structure Fish Europe Density dependent effects as key drivers of intraspecific size structure of six abundant fish species in lakes across Europe Arranz I., Mehner T., Benejam L., Argillier C., Holmgren K., Jeppesen E., Lauridsen T. L., Volta P., Winfield I. J., Brucet S. Arranz, Ignasi e Benejam, Lluis Aquatic Ecology Group, BETA Technology Centre, University of Vic Central University of Catalonia, Vic, Catalonia, Spain; Mehner, Thomas Leibniz Institute of Freshwater Ecology and Inland Fisheries, Muggelseedamm 310, Berlin, Germany; Argillier, Christine Irstea UR HYAX, Centre d Aix en Provence, F 13182, France; Holmgren, Kerstin Institute of Freshwater Research, Department of Aquatic Resources, Swedish University of Agricultural Sciences, Stångholmsvagen 2, SE 178 93 Drottningholm, Sweden; Jeppesen, Erik e Lauridsen, Torben L. e Brucet, Sandra Lake Ecology Section and Arctic Research Centre, Department of Bioscience, Aarhus University, Vejlsøvej 25, 8600 Silkeborg, Denmark; Sino Danish Center for Education and Research SDC , Beijing, China; Volta, Pietro CNR ISE, Pallanza Verbania; Winfield, Ian J. Lake Ecosystems Group, Centre for Ecology Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster, LA1 4AP, U.K We studied fish size structure by using mean size, size diversity, and the slope of linear size spectra of six common European fish species along large scale environmental gradients. We further analyzed the response of these three size metrics to environmental variables and to density dependent effects, i.e., relative estimates of abundance catch per unit effort, CPUE . We found differences in the strength of main predictors of size structure between the six species, but the direction of the response was relatively similar and consistent for most of the size metrics. Mean body size was negatively related to temperature for perch Perca fluviatilis , roach Rutilus rutilus , and ruffe Gymnocephalus cernuus . Lake productivity expressed as total phosphorus concentration and lake depth were also predictors of size structure for four of six species. Moreover, we found a strong density dependence of size structure for all species, resulting in lower mean body size and size diversity and steeper size spectra slopes when density dependence increases. This suggests that density dependence is a key driver of fish size structure. 72 Published version http //www.nrcresearchpress.com/doi/abs/10.1139/cjfas 2014 0508#.Vh0A5Csroo8 Article Articolo Arranz I et al 2016 Can J Fish Aq Sci.pdf Articolo in rivista National Research Council Canada. 0706 652X Canadian journal of fisheries and aquatic sciences Print Canadian journal of fisheries and aquatic sciences Print Can. j. fish. aquat. sci. Print Canadian journal of fisheries and aquatic sciences. Print Journal canadien des sciences halieutiques et aquatiques Print pietro.volta VOLTA PIETRO |
