The Relationships and Evolution of the Dendroica coronata Complex

THE Dendroica coronata complex is generally considered as consisting of two distinct but closely related and essentially allopatric species, the Myrtle Warbler (D. coronata) and Audubon's Warbler (D. auduboni). The breeding range of D. coronata is the boreal forest of northern North America, and that of D. auduboni is the cordilleran forests of the western part of the continent. In Alberta, British Columbia, and perhaps southeastern Alaska, their ranges are in contact and the two forms interbreed. Although specimens were collected from the area of interbreeding as long ago as 1891 and hybridization between the two forms has been alleged since 190'9 (Taylor, 1911), no complete study of the complex has previously been made, and only a few minor details have been published (Taverner, 1918; Cowan, 1955).