Figure 1. Understanding bird-window collisions at the Fitzpatrick Center building at Duke University, North Carolina USA.

(A) Insets show the location of Duke University, and bird-friendly pattern of dots applied to some windows. (B) Reported cardinal directions of impacted building faces (with a 20-m buffer displayed); dots represent observations for which no data or letters other than N, E, S or W were entered. (C) A kernel density function of mapped collision points. (D) Collision observations snapped to the building perimeter and treated with a point density function.