Prothonotary warbler

In Canada, the Prothonotary warbler is only known to nest in southwestern Ontario, primarily along the north shore of Lake Erie. Over half of the small and declining population is found in Rondeau Provincial Park. In Ontario, the Prothonotary warbler is found in the warmer climate of the Carolinian deciduous forests. In 2015, it was estimated that there were only between 28 mature individuals in Ontario.

The main threats to the Prothonotary warbler are habitat destruction caused by the removal of dead and living trees, and the draining of the forested swamps that make up their exclusive habitat. Another concern is the continuing loss of wintering habitat, especially mangrove swamps, in Central and South America. Competition from other birds, like the House wren and Brown-headed Cowbird, is a threat in some areas.