During winter small passerines foraging solitarily at feeders showed two different types of vigilance: the vigilance before initiating feeding that is the time needed to assess the potential risks at the patch (waiting time), and the vigilance related to the continuous scanning of the surroundings while foraging (vigilance rate). The waiting time differed significantly among the species, but vigilance rate did not. Patch residence time also differed among the species, being directly related to the waiting time, because the longer the residence time of the forager, the higher the possibility for ambush predators or competitors to reach it. Patch residence time was inversely related to bill length. This probably results from the different quantity of food per foraging time reached by different bill-sized species. Neither waiting time nor patch residence time when solitary were related to social dominance, hoarding behaviour, or species-specific traits associated with the habit of hanging upside down.
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