Tail-wagging, solitary, active flycatcher. Common in the East in warmer months; an early spring migrant. Medium-sized, large-headed, gray-brown back with buffy or white underparts. Nearly always wags tail when perched; perches low and flies out to catch insects, its primary food source (with occasional seeds or berries). Mud and vegetation nest, often on human structures with ledges, niches, walls or other solid base. Lifespan up to 10 years. Population ~ 32 million and stable.