It closely resembles a ruby-crowned kinglet, but has a thicker bill, blue-gray legs, and is slightly larger in size.

Recent DNA studies suggest this species may be split into at least 2 different species, with coastal Pacific birds showing enough genetic variation when compared to interior ones.

This vireo makes a hanging cup nest suspended from a fork of a tree.

It feeds by gleaning insects as it deliberately moves through the forest canopy.

Birds are mostly resident year-round, but there may be some altitudinal and short distance migration.