Can I have fries with that? Context-dependent foraging behavior in urban and rural American crows

Abstract

Behavioral flexibility and the ability to respond appropriately to anthropogenic cues that signal potential threats or rewards may promote the success of wild animals in the urban environment. Here, we examine the behavioral responses to anthropogenic cues of free-living American crows (Corvus brachyrhynchos), an opportunistic scavenger and common urban exploiter. Specifically, we tested the hypotheses that crows would more readily approach (1) novel objects and anthropogenic food when in close proximity to trash cans, and (2) paper bags with hidden food rewards when closer to a McDonald's restaurant, due to their associations of food with these cues. In addition, we examined the preference of crows for bags marked with a McDonald's logo vs. unmarked bags, hypothesizing that crows closer to McDonald's would be more likely to approach the labeled bag because of its familiarity. Consistent with our expectations, crows exhibited a lower approach latency to anthropogenic food and novel objects in close proximity to trash cans. Likewise, they were more likely to approach paper bags when in proximity to a McDonald's restaurant, but they showed no preference for bags with a McDonald's logo. Overall, we found evidence that the foraging behavior of crows varied in the presence of specific anthropogenic cues and that these responses depended on their probable cue familiarity. Their ability to use anthropogenic cues specific to the local environment, combined with their exploitation of human food resources, likely contributes to the success of the American crow in the city.