Family: Parulidae, Wood Warblers view all from this family

Description 4 3/4-5 1/2" (12-14 cm). Slate gray hood extending to upper breast, where it darkens to black. Olive green above, yellow below; female slightly paler. Both sexes have broken white eye ring. In fall, hood lighter, broken eye ring less distinct.

Habitat Coniferous forest edges, burns, brushy cuts, or second-growth alder thickets and streamside growth.

Nesting 3-5 white eggs, with brown spotting, in a grassy cup nest close to the ground in a bush or tall weeds.

Range Breeds from Alaska and Yukon south to California and central New Mexico. Winters in tropics.

Voice   Song a chanting tree tree tree tree sweet sweet! Call a loud tik, sharper than the calls of most other western warblers.

Discussion MacGillivray's is a common western warbler. Two similarly hooded warblers occur east of the Rockies, the Connecticut Warbler (Oporornis agilis) and the Mourning Warbler (Oporornis philadelphia). No doubt these all originated from a common "hooded warbler" forebear during the vicissitudes of the past Ice Age, when during warm interglacial periods the forests expanded, only to be split again when the cold grip of the glaciers returned.