Effect of Urbanization on Neophobia in Black-capped Chickadees (Poecile atricapillus)

Abstract

As human populations increase and city borders grow, many animals have to modify their foraging behaviours to exploit evolutionarily novel urban food sources that could aid their survival. Neophobia, the fear of novelty, can lead to missed opportunities in these cases. Novelty is therefore expected to elicit different responses in urban and rural populations, a difference that has been frequently studied, but with mixed results. The main objective of my thesis was to study the novelty response of wild black-capped chickadees (Poecile atricapillus) in ecologically relevant conditions while controlling for individual characteristics and potential differences in foraging group size. I predicted that urban black-capped chickadees would be more likely to initially contact novelty than rural chickadees, and that subordinates and juveniles would be more likely to first contact novelty than dominants and adults, respectively. I ran replicated experiments using three novelty types (object, colour, or food) on six sites, during which I registered feeder choice of 71 tagged individuals. I found that urban chickadees showed less neophobia than their rural counterparts, the latter initially contacting the familiar feeder before approaching the novel feeder, while the former were equally likely to contact any feeder. There was no significant effect of an individual’s dominance, age or sex on its first choice of feeder, nor was there an effect of novelty type. Overall, my results suggest that urban chickadees exhibit less neophobia than their rural counterparts, because they have generally learned to tolerate novelty in their habitat and/or they have adapted to live in an environment that rewards low neophobia.