During our week in Olympia last July, we often took short neighborhood strolls. We saw a few Violet-green Swallows. These birds are similar to Tree Swallows, but Violet-greens have more white on their faces (and different-patterned tails).
Violet-green swallows breed mainly in mountainous coniferous forests. They often nest in old woodpecker holes and, unlike Tree Swallows, rarely use bird-boxes (Brown and Damrose 2011). After breeding, Violet-greens move to lower elevations, so the individual in this photo may not be a local bird. This species breeds in western North America, from Canada south to Mexico, and is only rarely observed east of the Rocky Mountains.