Impact of climate change on the distribution of brown trout, Salmo trutta Linnaeus, 1758 (Teleostei: Salmonidae) using ensemble modelling approach in Iran



In recent decades, climate change and other anthropogenic pressures have seriously influenced freshwater biodiversity to decline faster than terrestrial biodiversity. This trend is likely to be continued in the future. We assessed the impact of climate change on the distribution of brown trout in Iran by simulating their conditions under optimistic and pessimistic climate change scenarios (RCP 2.6 and RCP 8.5) in 2050 and 2080 by using species distribution models (SDMs) tool and ensemble forecasting approach. The results showed a significant reduction in the distribution range of this species (100%) in our database in all optimistic and pessimistic climate change scenarios. Moreover, no new potential sites were predicted in those scenarios. These outcomes seriously warn that a conservation and management plans are required to protect this species in future.


Brown trout, Species Distribution Modelling, Conservation, Range distribution.

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Abbaspour, K.C.; Faramarzi, M; Ghasemi, S.S. & Yang, H. 2009. Assessing the impact of climate change on water resources in Iran. Water Resources Research 45: 1-16.

Abdoli, A. 2017. The Field Guide of Inland Water Fishes of Iran. Iran-shenasi, Tehran.

Amiri, M.J. & Eslamian, S.S. 2010. Investigation of climate change in Iran. Journal of Environmental Science and Technology 3: 208-216.

Araújo, M.B. & New, M. 2007. Ensemble forecasting of species distributions. Trends in Ecology and Evolution 22: 42-47.

Berg, L. 1949. Presnovodnye ryby Irana i sopredel'nykh stran [Freshwater fishes of Iran and adjacent countries]. Trudy Zoologicheskogo Instituta Akademii Nauk SSSR 8: 783-858.

Berteaux, D.; Réale, D.; McAdam, A.G. & Boutin, S. 2004. Keeping pace with fast climate change: Can arctic life count on evolution? Integrative and Comparative Biology, 44:140-151.

Chefaoui, R.M. & Lobo, J.M. 2008. Assessing the effects of pseudo-absences on predictive distribution model performance. Ecological Modelling, 210: 478-486.

Coad, B.W. 2018. Freshwater fishes of Iran. available at:

Dudgeon, D.; Arthington, A.H.; Gessner, M.O.; Kawabata, Z.; Knowler, D.J.; L eveque, C.; Naiman, R.J.; Prieur-Richard, A.H.; Soto, D.; Stiassny, M.L. & Sullivan, C.A. 2006. Freshwater biodiversity: importance, threats, status and conservation challenges. Biological Reviews 81: 163-182.

Elliott, J.M. 1994. Quantitative Ecology and the Brown Trout. Oxford University Press, New York.

Filipe, A.F.; Markovic, D.; Pletterbauer, F.; Tisseuil, C.; De Wever A.; Schmutz, S.; Bonada, N. & Freyhof, J. 2013. Forecasting fish distribution along stream networks: brown trout (Salmo trutta) in Europe. Diversity and Distributions 19: 1059-1071.

Finstad, A.G.; Forseth, T.; Jonssonw, B.; Bellier, E.; Hesthagen, T.; Jensen, A.; Hessenz, D.O. & Foldvik, A. 2011. Competitive exclusion along climate gradients: energy efficiency influences the distribution of two salmonid fishes. Global Change Biology 17: 1703-1711.

Hijmans, R.J.; Cameron, S.E. & Parra, J.L. 2007. WorldClim Version 1.4. Museum of Vertebrate Zoology, University of California, Available at:

Hijmans, R.J.; Cameron, S.E.; Parra, J.L.; Jones, P.G. & Jarvis, A. 2005. Very high resolution interpolated climate surfaces for global land areas. International Journal of Climatology 25: 1965-1978.

Launey, S.; Brunet, G.; Guyomard, R. & Davaine, P. 2010. Role of introduction history and landscape in the range expansion of brown trout (Salmo trutta L.) in the Kerguelen Islands. Journal of Heredity 101: 270-283.

Lindner, M.; Fitzgerald, J.B.; Zimmermann, N.E.; Reyer, C.; Delzon, S.; van der Maaten, E.; Schelhaas, M.J.; Lasch, P.; Eggers, J.; van der MaatenTheunissen, M.; Suckow, F.; Psomas, A.; Poulter, B. & Hanewinkel, M. 2014. Climate change and European forests: what do we know, what are the uncertainties, and what are the implications for forest management? Journal of Environmental Management 146: 69-83.

Lovejoy, T.E. & Hannah, L.J. 2006. Climate Change and Biodiversity. Yale University Press, New Haven, CT. Millennium Ecosystem Assessment. 2005a. Ecosystems and Human Well-being: General Synthesis, edn. Island Press, Washington D.C.

MacDonald, R.W. 2005. Climate change, risks and contaminants: a perspective from studying the Arctic. Human and Ecological Risk Assessment 11: 1099-1104.

McGinnity, P.; Jennings, E.; deEyto, E.; Allott, N.; Samuelsson, P.; Rogan, G.; Whelan, K. & Cross, T. 2009. Impact of naturally spawning captive-bred Atlantic salmon on wild populations: depressed recruitment and increased risk of climate-mediated extinction. Proceedings of the Royal Society B: Biological Science 276: 3601-3610.

Moss, B.; Hering, D. & Green, A.J. 2009. Climate change and the future of freshwater biodiversity in Europe: a primer for policy-makers. Freshwater Reviews 2: 103-130.

Mostafavi, H.; Pletterbauer, F.; Coad, B.W.; Mahini, A.S.; Schinegger, R.; Unfer, G; Trautwein, C. & Schmutz, S. 2014. Predicting presence and absence of trout (Salmo trutta) in Iran. Limnologica-Ecology and Management of Inland Waters 46: 1-8.

Mostafavi, H.; Schinegger, R.; Melcher, A.; Moder, K.; Mielach, C. & Schmutz, S. 2015. A new fish-based multi-metric assessment index for cyprinid streams in the Iranian Caspian Sea Basin. Limnologica-Ecology and Management of Inland Waters 51: 37-52.

Olden, J.D.; Kennard, M.J.; Leprieur, F.; Tedesco, P.A.; Winemiller, K.O. & Garcıa-Berthou, E. 2010. Conservation biogeography of freshwater fishes: recent progress and future challenges. Diversity and Distributions 16: 496-513.

Peterson, J.T. & Kwak, T.J. 1999. Modeling the effects of land use and climate change on riverine smallmouth bass. Ecological Applications 9: 1391-1404.

Pont, D.; Hughes, R.M.; Whittier, T.R.; Schmutz, S. 2009. A predictive index of biotic integrity model for aquatic-vertebrate assemblages of western U.S. streams. Transactions of the American Fisheries Society 138: 292-305.

Portner, H.O.; Schulte, P.M.; Wood, C.M. & Schiemer, F. 2010. Niche dimensions in fishes: an integrative view. Physiological and Biochemical Zoology 83: 808-826.

Saadati, M.A.G. 1977. Taxonomy and Distribution of the Freshwater Fishes of Iran. State University, Fort Collins, CO.

Schindler, D.W. 2001. The cumulative effects of climate warming and other human stresses on Canadian freshwaters in the new millennium. Canadian Journal of Fisheries and Aquatic Sciences 58: 18-29.

Swets, J.A. 1988. Measuring the Accuracy of Diagnostic Systems. Science 240: 1285-1293.

Thuiller, W. 2003. BIOMOD – optimizing predictions of species distributions and projecting potential future shifts under global change. Global Change Biology 9:


Thuiller, W. 2004. Patterns and uncertainties of species’ range shifts under climate change. Global Change Biology 10: 2020-2027.

Thuiller, W.; Araujo, M.B.; Pearson, R.G. & Whittaker, R.J. 2004a. Uncertainty in predictions of extinction risk. Nature 427: 145-148.

Thuiller, W.; Brotons, L.; Araujo, M.B. & Lavorel, S. 2004b. Effects of restricting environmental range of data to project current and future species distributions. Ecography 27: 165-172.

Thuiller, W.; Lafourcade, B.; Araújo, M. 2009a. ModOperating Manual for BIOMOD.

Université Joseph Fourie, LaboratoireD’Ecologie Alpine.

Thuiller, W.; Lafourcade, B.; Engler, R. & Araújo, M.B. 2009b. BIOMOD – a platform for

ensemble forecasting of species distributions. Ecography 32: 369-373.

Valavi, R.; Shafizadeh-Moghadam, H.; Matkan, A.A.; Shakiba, A.; Mirbagheri, B. & Kia, S.H. 2018. Modelling climate change effects on Zagros forests in Iran using individual and ensemble forecasting approaches. 25-z

Valiente, A.G.; Juanes, F.; Nunez, P. & Garcia-Vazquez, E. 2010. Brown trout (Salmo trutta) invasiveness: plasticity in life-history is more important than genetic variability. Biological Invasions, 12: 451–462.

Vogt, J.; Colombo, R.; Paracchini, M.L.; de Jager, A. & Soille, P. 2003. CMM river and catchment database. EUR 20756 EN, EC-JRC, Inspra.

Vogt, J.; Soille, P.; de Jaeger, A.; Rimaviciute, E.; Mehl, W.; Foisneau, S.; Bódis, K.; Dusart, J.; Paracchini, M.L.; Haastrup, P. & Bamps, C. 2007. A Pan-European river and catchment database. EC-JRC (Report EUR 22920 EN) Luxembourg. Available at: (accessed 2 January 2012).

Wenger, S.J.; Isaak, D.J.; Luce, C.H.; Neville, H.M.; Fausch, K.D.; Dunham, J.B.; Dauwalter, D.C.; Young, M.K.; Elsner, M.M.; Rieman, B.E.; Hamlet, A.F. & Williams, J.E. 2011. Flow regime, temperature, and biotic interactions drive differential declines of trout species under climate change. Proceedings of the National Academy of Sciences of the United States of America 108: 14175-14180.

Woodward, G.; Perkins, D.M. & Brown, L.E. 2010. Climate change and freshwater ecosystems: impacts across multiple levels of organization. Philosophical Transactions of the Royal Society of London B: Biological Sciences 365: 2093-106.


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