Food resource partitioning of Arctic charr, Salvelinus alpinus (L.) and three‐spined stickleback, Gasterosteus aculeatus L., in the littoral zone of lake Takvatn in northern Norway

• Published in: Ecology of Freshwater Fish
• Main Authors: Jørgensen, L., Klemetsen, A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1995
• Subjects: Ecology; Aquatic Science; Ecology, Evolution, Behavior and Systematics; Arctic; Norway; Arctic charr; Northern Norway; Salvelinus alpinus; Zooplankton
• Online Access: http://dx.doi.org/10.1111/j.1600-0633.1995.tb00120.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1600-0633.1995.tb00120.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1600-0633.1995.tb00120.x

Abstract The food resource partitioning of Arctic charr ( Salvelinus alpinus L.) and three‐spined stickleback ( Gasterosteus aculeatus L.) were investigated in the littoral zone of lake Takvatn in northern Norway in the ice‐free period June–November. Charr and sticklebacks had different feeding habits. Sticklebacks ate several small benthic prey items that were never eaten by charr, and the sticklebacks' diet were dominated by the benthic microcrustaceans Chydoridae and Ostracoda, chironomid larvae and stickleback eggs. Small charr (<17 cm) consumed a wide spectrum of chironomid pupae, terrestrial insects and zooplankton. Intermediate (17–20 cm) and small charr had quite similar feeding habits, while large charr (>20 cm) frequently ate both benthos, pelagic and terrestrial food. The diet overlap between small charr and sticklebacks was never larger than 0.6 (Schoener's index). The segregation in feeding habits indicates that small charr and sticklebacks are segregated in microhabitat when they are both in the littoral zone.