Neophobia in the foraging-site selection of a neotropical migrant bird: An experimental study.

I hand-raised chestnut-sided warblers (Dendroica pensylvanica) in a room with eight experimental microhabitats; the microhabitats were removed after 6 weeks. I then measured the response of the warblers to the eight "natal" and eight "novel" microhabitats in two experiments conducted 2 and 4 months after removal. Chestnut-sided warblers responded with decreased feeding latency (neophobia) and a greater preference for foraging at the natal microhabitats. I suggest that an ontogenetic increase in neophobia restricts chestnut-sided warblers to foraging at microhabitats most similar to those experienced as juveniles.