Bay-breasted Warbler

A Bay-breasted warbler from my SONGBIRDS OF PELEE WORKSHOP at Point Pelee National Park of Canada.

In contrast to the more stable populations of other warblers, Bay-breasted Warbler numbers go up and down depending on spruce budworm outbreaks. The birds are abundant during infestations but decline or disappear from some areas a few years later. A similar relationship with spruce budworm exists for Tennessee and Cape May Warblers. Blackburnian and Blackpoll Warblers also readily consume budworms but are not as specialized in their diets.