Introduction

Adult male Magnolia Warbler, breeding plumage, Huntsville, ON, June.

Figure 1. Distribution of the Magnolia Warbler.

Editor’s Note: Phylogenetic analyses of sequences of mitochondrial and nuclear DNA indicate that all species formerly placed in Dendroica, one species formerly placed in Wilsonia (citrina), and two species formerly placed in Parula (americana and pitiayumi) form a clade with the single species traditionally placed in Setophaga (ruticilla). The generic name Setophaga has priority for this clade. See the 52nd Supplement to the AOU Checklist of North American Birds for details. Future revisions of this account will reflect these changes.

The Magnolia Warbler, a boreal forest breeder, has conspicuous black and yellow markings and a distinctive tail pattern, making it one of North America’s more recognized wood-warblers. Alexander Wilson collected the first specimen of this species in 1810 from a magnolia tree in Mississippi and gave it the inappropriate specific name magnolia, but his English name for the species was Black-and-yellow Warbler.

The Magnolia Warbler nests alongside the congeneric Black-throated Green (D. virens), Blackburnian (D. fusca), and Yellow-rumped (D. coronata) warblers, but unlike the first two of these, the Magnolia Warbler is a bird of dense young growth. It usually nests in conifers – spruce (Picea spp.) in northern parts of the range and eastern hemlock (Tsuga canadensis) in the south. Nests are seldom found more than 5 meters above ground. This is an active species, with males vigorously chasing other males and females, even during migration.

Despite its numerical abundance and conspicuous behavior, the Magnolia Warbler has been little studied, and many aspects of its breeding biology remain poorly known. Nests are difficult to find in the dense breeding habitat this species favors, and only a few have been watched systematically, providing little information on nesting success and productivity. Essentially nothing is known about the critical period between fledging and the first autumn migration. Magnolia Warbler populations presently appear to be stable across most of the range, and the species is not considered a conservation priority (Partners in Flight Species Assessment Database 2005).