Environmental Biology of Fishes

, Volume 83, Issue 1, pp 7–15 | Cite as

Charr truth: sympatric differentiation in Salvelinus species

  • David L. G. Noakes


Charrs, Salvelinus species, are characteristic fishes of northern freshwater lakes and rivers. They are highly variable in almost every aspect of their behaviour, morphology and life history. Several possible explanations have been proposed to account for this variability and resolve the taxonomic confusion in this genus. I propose that sympatric trophic polymorphism, in the ecological context of these species, can make sense of this variability. I use examples from charr in Canada and Iceland to construct an evolutionary scenario for this genus.


Salvelinus species Resource polymorphism Sympatric speciation Evolution Behavior 



Thanks to all who have contributed to the ongoing research program in my laboratory over the years—many are co-authors of references cited herein. My research has been supported by NSERC Canada, Fisheries & Oceans Canada, Ontario Ministry of Natural Resources, World Wildlife Fund of Canada, Japan Society for the Promotion of Science, Ontario Ministry of the Environment, Ontario Hydro, Ontario Federation of Anglers and Hunters, Rannis (Icelandic Science Foundation), the Great Lakes Fishery Commission, Oregon Department of Fish and Wildlife and Oregon State University. Craig Blackie gave permission to use his photographs. An earlier version of this paper was presented at the 2004 Annual Meeting of the American Fisheries Society, and I benefited from helpful comments and discussion at that occasion. Special thanks to Skuli Skulason, Siggi Snorrason and Bjarni Kristjansson for their comments on the latest version of this manuscript.


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© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  1. 1.Oregon State UniversityCorvallisUSA

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