A Mother Redstart's Wrath

As anthropogenic activities increasingly disturb ecosystems, it is important to determine how wildlife is impacted. This photo was taken during field work for the Ontario Breeding Bird Atlas-3--a project aimed at understanding the temporal differences in distribution and abundance of Ontario's breeding birds. This little American redstart (Setophaga ruticilla) is screaming at me because I've likely ventured too close to her nest and she's trying to distract me. This observation adds to our understanding of American redstart breeding behaviors, phenology, and distribution.
A small yellow and grey bird standing on a branch with its mouth open like its screaming.