The Blue-gray Gnatcatcher is a remarkably energetic songbird, easily identified in the field by its distinctively long, notched tail that it frequently flicks as it maneuvers through the canopy. While often overlooked due to its diminutive size and swift movements, this species is admired by birdwatchers for its complex, wheezy song and its sophisticated nest-building habits, which involve decorating the exterior with lichen to camouflage it against tree branches.