Marine migrations and trophic niche use of Arctic Char in southwest Greenland fjords with contrasting influxes from glacial runoff
Davidsen, J.G.; Eldoy, S.H.; Piper, A.T.; Whoriskey, F.; Friis, M.E.L.; Reubens, J.; Thorstad, E.B.; Stefanov, T.; Gaber, H.; Sjursen, A.D.; Brodersen, J.; Power, M. (2026). Marine migrations and trophic niche use of Arctic Char in southwest Greenland fjords with contrasting influxes from glacial runoff. Can. J. Fish. Aquat. Sci. 83: 0410. https://dx.doi.org/10.1139/cjfas-2025-0410
In: Canadian Journal of Fisheries and Aquatic Sciences = Journal canadien des sciences halieutiques et aquatiques. National Research Council Canada: Ottawa. ISSN 0706-652X; e-ISSN 1205-7533, meer
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| Author keywords |
Arctic Char;acoustic telemetry;glacial runoff;migration ecology;Salvelinus alpinus;stable isotope analysis;trout salmo-trutta;salvelinus-alpinus l.;stable-isotope ratios;climate-change;temporal variability;fresh-water;temperature;salar;food;productivity |
| Auteurs | | Top |
- Davidsen, J.G., meer
- Eldoy, S.H.
- Piper, A.T.
- Whoriskey, F.
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- Friis, M.E.L.
- Reubens, J.
- Thorstad, E.B., meer
- Stefanov, T.
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- Gaber, H.
- Sjursen, A.D.
- Brodersen, J.
- Power, M.
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| Abstract |
The facultatively migratory Arctic Char often undertakes annual marine feeding migrations. Climate-driven environmental changes such as increased glacial runoff can alter selective pressures shaping migration behaviour. To assess environmentrelated influences on migratory patterns and trophic niche use, we combined acoustic telemetry with otolith and stable isotope analyses to study two southwestern Greenland char populations in fjords (Igaliku and Ikersuaq) differing in glacial runoff. Anadromous char in Igaliku had a mean maximum travel of 21 km from their home river, while those in the more glacially influenced Ikersuaq remained near shore with shorter movements (mean 9 km). Despite similar marine feeding durations (mean 48 vs. 54 days), Ikersuaq fish exhibited lower marine feeding intensity. Arctic Char in Igaliku Fjord experienced warmer (mean 8.0 degrees C) conditions than those in Ikersuaq Fjord (5.7 degrees C), with estuaries (Igaliku 8.5 degrees C; Ikersuaq 7.2 degrees C) consistently warmer than marine areas in both systems. Findings suggest that where Arctic Char feeding and habitat use are less constrained by high glacial runoff, they may shift to more open waters altering diet and life-history strategies. |
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