Western wood pewees are mostly gray or brownish gray, with a crown of feathers that can be extended to enlarge the appearance of the head. There is no white eye ring. The bill is dark with a yellowish tint to the lower mandible. Long wings with 2 light wing bars serve as distinctive identifying characteristics. The body is 5-6 inches long.

This fly catcher breeds in open pine/oak or conifer forests and riparian cottonwood and willow groves. Breeding habitat covers most of New Mexico apart from the far eastern edge and some southern desert habitats, as well as most of the western U.S. through western Canada and into Alaska. Pewees migrate south at the end of the summer and winter in northern and western South America.

In foraging, wood pewees watch from a perch and fly out to catch an insect in the air, then return to a perch. A variety of flying insects constitute the major diet but the birds will also take berries and some ground insects. The nest is an open cup structure out on a limb of a conifer or deciduous tree. The female incubates 2-4 eggs and both parents feed the nestlings.

The species is currently common and widespread and not of great conservation concern, though populations are declining overall due to habitat loss in breeding and wintering areas. The Audubon Society predicts that as the climate warms Pewees will experience habitat losses at the periphery of the range, with substantial reductions in eastern Alberta, Canada.