Despite its name, this species does not nest in prairies. In Canada, Prairie Warblers are found only in Ontario, in early successional vegetation. The core breeding population is located along the southeastern shore of Georgian Bay, where they nest in rock barrens with sparse and scrubby vegetation. The species is rare along the southern edge of the Shield, where scattered records exist and no systematic surveys have occurred previously. The entire Ontario population is estimated to be no more than 320 pairs.
To guide our surveys, we used a habitat model created by Andrew Campomizzi, BECO's Research Scientist. The model indicates the probability of occurrence of Prairie Warblers, based on habitat associations where the species has been detected previously.