Among the most striking of migratory songbirds, blackburnian warblers are the only warblers with an orange throat. Considered “treetop experts” because of their preference for nesting high in the forest canopy, these warblers have been known to build their nests 80 feet above the ground. They prefer to nest in mature forests and occur at highest densities in true old growth forests, such as Canada’s boreal forest where nearly 60 percent of the blackburnian warbler’s global population breeds.
A nocturnal migrant whose populations are considered relatively stable for now, the blackburnian warbler embarks on a lengthy migration every year. From its breeding grounds in the boreal forest and across the northern U.S. from Minnesota to Massachusetts, the blackburnian travels to winter in the highlands from Costa Rica to Venezuela and Peru. Along the way, it relies on important stopover sites along America’s Gulf Coast.
Except during migration and breeding, blackburnian warblers are largely solitary. They form pair bonds that are monogamous during the breeding season and only move together in flocks during migration. Though their populations are currently listed as stable, blackburnian warblers are at risk as the rates of deforestation in their breeding grounds from the northern U.S. to the boreal forest increases.March 07, 2011