Impacts of climate warming on the long-term dynamics of key fish species in 24 European lakes

• Published in: Hydrobiologia
• Main Authors: Jeppesen, Erik, Mehner, Thomas, Winfield, Ian J., Kangur, Kulli, Sarvala, Jouko, Gerdeaux, Daniel, Rask, Martti, Malmquist, Hilmar J., Holmgren, Kerstin, Volta, Pietro, Romo, Susana, Eckmann, Reiner, Sandstrom, Alfred, Blanco, Saul, Kangur, Andu, Stabo, Ragnarsson Henrik, Tarvainen, Marjo, Ventela, Anne-Mari, S?ndergaard, Martin, Lauridsen, Torben L., Meerhoff, Mariana
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer 2012
• Subjects: Climate change; Fish assemblages; Functional traits; Long-term data series; Europe; Arctic; Arctic charr
• Online Access: http://puma.isti.cnr.it/dfdownloadnew.php?ident=cnr.ise/cnr.ise/2012-A0-064; http://puma.isti.cnr.it/rmydownload.php?filename=cnr.ise/cnr.ise/2012-A0-064/2012-A0-064_0.pdf

Fish play a key role in the trophic dynamics of lakes.With climatewarming, complex changes in fish assemblage structure may be expected owing to direct effects of temperature and indirect effects operating through eutrophication, water level changes, stratification and salinisation. We reviewed published and new long-term (10-100 years) fish data series from 24 European lakes (area: 0.04-5,648 km2; mean depth: 1-177 m; a north-south gradient from Sweden to Spain). Along with an annual temperature increase of about 0.15-0.3_C per decade profound changes have occurred in either fish assemblage composition, body size and/or age structure during recent decades and a shift towards higher dominance of eurythermal species. These shifts have occurred despite a reduction in nutrient loading in many of the lakes that should have benefited the larger-sized individuals and the fish species typically inhabiting cold-water, low-nutrient lakes. The cold-stenothermic Arctic charr has been particularly affected and its abundance has decreased in the majority of the lakes where its presence was recorded. The harvest of cool-stenothermal brown trout has decreased.