Response of Mallard Ducklings to Variation in Habitat Quality: An Experiment of Food Limitation

Abstract

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Balancing between predation risk and food by boreal breeding ducks

“…The number of broods at the water bodies was only weakly dependent on the number of pairs, which can be a reflection of differing habitat requirements of pairs and broods (Holopainen et al, 2015) or high nest predation and brood mortality. Sjoberg et al (2000) showed for mallards that all lakes used by pairs are not suitable for broods, the difference in lake use between pairs and broods being due to food limitation at the brood stage (Gunnarsson et al , 2004). In boreal lakes food limitation can be intensified due to food competition between ducks and fish (Nummi et al, 2016).…”