Mourning warbler.
Rondeau Provincial Park, Ontario, Canada, May 22, 2024. One we don't get to see very often so it is always a pleasure when one shows up. Geothlypis philadelphia. Mourning Warblers are bright but hard-to-see birds of brushy areas. Among the most renowned skulkers of the warbler family, they are common but seldom seen, particularly during migration and winter, when they are quiet. source -allaboutbirds-org.