The population biology and life history traits of Eurasian ruffe [Gymnocephalus cernuus (L.), Pisces: Percidae] introduced into eutrophic and oligotrophic lakes in Northern Italy

  • Pietro Volta | p.volta@ise.cnr.it CNR Institute of Ecosystem Study, Italy.
  • Erik Jeppesen National Environmental Research Institute, Aarhus University, Silkeborg, Denmark.
  • Barbara Campi CNR Institute of Ecosystem Study, Italy.
  • Paolo Sala CNR Institute of Ecosystem Study, .
  • Matthias Emmrich Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany.
  • Ian Winfield Centre for Ecology & Hydrology, Lancaster Environment Centre, United Kingdom.

Abstract

We describe the population biology and life-history traits of two Eurasian ruffe [Gymnocephalus cernuus (L.), Pisces: Percidae] populations which have recently colonised two small lakes in the lake Maggiore catchment of Northern Italy, the eutrophic lake (l.) Ghirla (ruffe first recorded in the early 1990s) and the oligotrophic lake (l.) Mergozzo (ruffe first recorded during the present sampling in 2010). Survey gill net catches revealed that ruffe has become one of the most abundant fish species in both lakes. Relative weight and weight-length relationships indicated better growth of ruffe in l. Mergozzo. Thus, gonad weight, adjusted for body size, was higher in l. Mergozzo, indicating a stronger individual reproductive potential in the more recently colonised lake. The stomach contents of ruffe were dominated by chironomid larvae and other benthic organisms, while pelagic microcrustaceans only occurred in small amounts. The ratio of benthic vs pelagic prey in the diet increased with ruffe size. Ruffe intraspecific food niche overlap (based on prey numbers) between age classes was slightly higher in oligotrophic l. Mergozzo than in eutrophic l. Ghirla and decreased with age in both lakes

Dimensions

Altmetric

PlumX Metrics

Downloads

Download data is not yet available.
Published
2013-04-26
Info
Issue
Section
Original Articles
Supporting Agencies
European Union, Fondazione Comunitaria del VCO, Villum Kann Rasmussen Centre of Excellence project
Keywords:
invasive alien species, introductions, biological pressures, percids, diets
Statistics
  • Abstract views: 2670

  • PDF: 465
  • HTML: 1422
How to Cite
1.
Volta P, Jeppesen E, Campi B, Sala P, Emmrich M, Winfield I. The population biology and life history traits of Eurasian ruffe [Gymnocephalus cernuus (L.), Pisces: Percidae] introduced into eutrophic and oligotrophic lakes in Northern Italy. J Limnol [Internet]. 2013Apr.26 [cited 2020Oct.24];72(2):e22. Available from: https://jlimnol.it/index.php/jlimnol/article/view/jlimnol.2013.e22