Causes and consequences of invasions of aquatic ecosystems by non-native salmonids

Final Report Abstract

Salmonids (salmon and trout family) are highly valuable and have been translocated widely outside their native range since the 19th century. Ecological conditions, as well as history and culture, vary considerably within Europe, which has affected the current invasion potential for non-native salmonids. SalmoInvade is a research project within the BiodivERsA-network including scientists and stakeholders from Sweden, Norway, Germany, France and Canada. The project uses a multidisciplinary approach to evaluate the consequences of salmonid invasions in Europe and provide recommendations for their management. Biological studies: Global meta-analyses and experiments show that native salmonids can be adversely affected both by non-native populations and non-native species, sometimes with cascading effects on stream ecosystems. Furthermore, angling can be targeted to remove bold individuals in an invasive population. Social studies: Analyses of the governance systems for fisheries in the five countries showed considerable cross-national differences in how the establishment of non-native salmonids through stocking is managed. Furthermore, surveys on the public perception of biological invasions in Europe, as well as among stocking decisions makers in France and Germany, revealed considerable cross-national differences in how non-native and native salmonids are valued, and how contextual factors influence local stocking decisions. Policy implications: (1) Strict guidelines for stocking and transfer of non-native salmonids should be implemented. (2) Monitoring and reporting should be improved. (3) Local decision-makers and authorities should be empowered to enforce regulations and to evaluate practices for salmonid stocking. (4) In order to conserve Salmonid biodiversity in Europe, it is important to consider the variation in public perception of native salmonids, and to (5) improve science - policy - public cooperation and dialogue.

Publications

• (2017) Participatory adaptive management leads to environmental learning outcomes extending beyond the sphere of science. Science Advances 3 (6) e1602516
  Fujitani, M., McFall, A., Randler, C. & Arlinghaus, R.
  
• (2017) What determines the behavioral intention of local-level fisheries managers to alter fish stocking practices in freshwater recreational fisheries of two European countries?. Fisheries Research 194 173-187
  Riepe, Carsten; Fujitani, Marie; Cucherousset, Julien; Pagel, Thilo; Buoro, Mathieu; Santoul, Frédéric; Lassus, Rémy; Arlinghaus, Robert
  
• (2018) Salmonid stocking in five North Atlantic jurisdictions: Identifying drivers and barriers to policy change. Aquatic Conserv: Mar Freshw Ecosyst (Aquatic Conservation: Marine and Freshwater Ecosystems) 28 (6) 1451–1464
  Aas, Øystein; Cucherousset, Julien; Fleming, Ian A.; Wolter, Christian; Höjesjö, Johan; Buoro, Mathieu; Santoul, Frederic; Johnsson, Jörgen I.; Hindar, Kjetil; Arlinghaus, Robert
  
• (2019) Managing River Fish Biodiversity Generates Substantial Economic Benefits in Four European Countries. Environmental management 63 (6) 759–776
  Riepe, Carsten; Meyerhoff, Jürgen; Fujitani, Marie; Aas, Øystein; Radinger, Johannes; Kochalski, Sophia; Arlinghaus, Robert
  
• 2014. Species-specific preferences of German recreational anglers for freshwater fishing experiences, with emphasis on theintrinsic utilities of fish stocking and wild fishes. Journal of Fish Biology, 85: 1843-1867
  Arlinghaus, R., Beardmore, B., Riepe, C., Meyerhoff, J., Pagel, T.
  
• 2016. Global Salmonidae introductions reveal stronger ecological effects of changing intraspecific compared to interspecific diversity. Ecology Letters. 19: 1363–1371
  Buoro M., Olden J.D. & Cucherousset J.
  
• 2017. Co-existence with non-native brook trout breaks down the integration of phenotypic traits in brown trout parr. Functional Ecology
  Závorka, L., Koeck, B., Cucherousset, J., Brijs, J., Näslund, J., Aldvén, D., Höjesjö, J., Fleming, I. A. & Johnsson, J. I.
  
• 2017. Global test of Eltonian niche conservatism of non-native freshwater fish species between their native and introduced ranges. Ecography 40: 384-392
  Comte L., Cucherousset J. & Olden J.D.
  
• (2019): Angling selects against active and stress-resilient phenotypes in rainbow trout. In: Can. J. Fish. Aquat. Sci. 76 (2), S. 320–333
  Koeck B., Zavorka L., Aldven D., Näslund J., Arlinghaus R., Thörnqvist P.-O., Winberg S., Björnsson B. T. & Johnsson J. I.