Use of high-elevation coniferous scrub by breeding Common Yellowthroat (Geothlypis trichas) in western Newfoundland

Abstract

Common Yellowthroat (Geothlypis trichas) is an abundant passerine of dense vegetation, most commonly associated with wetlands across its pan-North American distribution. It has been reported using dry habitats in more southern areas;  however, habitat use in the boreal portion of its range is poorly understood. Historical observations of this species occupying coniferous scrub in Newfoundland suggest plasticity in breeding habitat near its northern range limit. To verify the probable breeding of Common Yellowthroat in dry, high-elevation (450–532 m above sea level), diminutive (0.5–1.0 m tall) coniferous scrub, we analyzed audio recordings from seven autonomous recording units deployed on plateaus in the Anguille Mountains portion of the Long Range Mountains of southwestern Newfoundland from late May to late July 2024. We detected males singing on territory almost daily from late May through mid-July at all seven sites, suggesting probable breeding. Therefore, we conclude that dry conifer scrub serves as breeding habitat for Common Yellowthroat in Newfoundland, adding to the list of described habitats occupied by this species. Our findings, which are descriptive in nature, reinforce the need for more comprehensive assessments of habitat use and breeding success across the boreal portion of the species’ range.