Canada - Arctic charr as a model species in predicting consequences of climate change scenarios on freshwater ecosystems in the Arctic

Lakes in the High Arctic are characterized by low water temperature, long-term ice cover, low levels of nutrients and low biodiversity. Thus, minor climatic changes may be of great importance to Arctic freshwater fish by influencing individual growth rate and gonad development - two life history parameters that strongly affect production, year class strength and life history tactics. The circumpolar Arctic charr (Salvelinus alpinus) is the only freshwater fish in the High Arctic (like Svalbard), and inc ludes anadromous, freshwater resident, and landlocked populations. The charr grow very old (35 yr), and their otoliths provide a highly suitable tool for 1) oxygen isotope measurements, 2) growth back-calculations and 3) strontium content to detect anadro my. Thus, thermal reconstruction using oxygen isotopes linked with individual growth rates provides an ideal model for studies on how climatic (environmental) factors affect life history traits in Arctic freshwater fish communities. Based on the above i nformation, we propose to use the life history of Svalbard Arctic charr as a model for predicting the consequences of different climate change scenarios on freshwater ecosystems in the Arctic. The objective of this pre-project is thus to bring together scientific personnel from various ecological and environmental institutes in Norway and Canada, with expertise with northern freshwater fish and influences of environmental variability in northern and high-Arctic areas, to design a full project, where th e life history of Svalbard Arctic charr will be examined in relation to climate variability and change impacts in the context of adaptability, and thus used as a model for predicting the consequences of different climate change scenarios on freshwater eco systems in the Arctic.