Introduction

This little-studied wood-warbler breeds in the northeastern U.S., boreal Canada, and through the central ridge of the Allegheny Mountains to Tennessee and Georgia. It undertakes a long annual migration for a wood-warbler, wintering in northern South America. It is often referred to as the “Necklaced Warbler” because of the pattern of black spots across its bright yellow breast.

During the breeding season, the Canada Warbler inhabits many sorts of forest growth, but is most abundant in cool, moist forests with a mix of coniferous and deciduous trees and a dense understory. It frequents rhododendron thickets in montane areas in the south, steep aspen/poplar forests in the north, and forested wetlands/swamps in the central part of its range. It is often associated with areas having abundant sphagnum moss cover and it nests on or near the ground in recessed pockets within moss hummocks or upturned tree-root masses. This species spends relatively little time on its breeding grounds, usually one of the last warblers to arrive and one of the first to depart local nesting areas. Canada Warblers often continue to sing late into the nesting cycle and even during fall migration.

This warbler eats a variety of insects and spiders and uses a variety of foraging techniques: foliage gleaning, ground foraging, and flycatching. It is an active species, its tail often cocked and wings flicking. In some areas, it feeds largely on the wing, which explains its old names: Canadian Flycatcher and Canadian Flycatching Warbler. It is socially monogamous and territorial during the breeding season and often joins mixed-species foraging flocks during winter.

Little is known of this species’ breeding biology; no extensive study has focused on the Canada Warbler. Length of incubation and nestling periods and annual reproductive success are among the many traits that have not been well documented in this species. Populations have declined steadily over the past 30 years, possibly in response to forest succession and loss of forested wetlands, making this species a high priority for management and monitoring.