Figure 2.

Exposure to an acute stressor affects territorial behavior differently in rural and urban birds. Circles and error bars denote means and standard errors of territorial behaviors during the pretreatment and the post‐treatment STI in control (black) and acute stressor (gray) treatments. An acute stressor did not affect singing in either population (A, B), although rural birds sang more in general. Treatment did not have a significant effect on median approach distance in urban birds (C), whereas in rural bids, stress treatment led to an increase in median approach distance while control birds did not change their behavior (D). Stress treatment had a similar effect on approach time in both urban (E) and rural (F) populations – in both cases, birds exposed to the stressor approached the lure more slowly, whereas control birds approached the lure more rapidly. The stressor had a different effect on number of flights in urban (G) and rural (H) birds: in the urban population, birds from both treatments reduced number of flights, whereas in the rural population, control birds increased while birds exposed to the stressor decreased number of flights.