"There are six swallow species in our area, and they are all incredible multi-tasking flyers who can communicate, catch insects and deftly swerve around each other all while flying. The Tree Swallow is one of our most common swallows and can live in a variety of habitats including human-made nest boxes because they are cavity-nesters. Tree Swallows and Violet-Green Swallows are often hard to tell apart if they are flying quickly and all you see is dark and light feathers versus their distinctive colors. A couple of key features to look for are: the Tree Swallow has a dark cap that covers over half of its head to below its eye, while the white on a Violet-Green face extends up the cheek and around the top of the back of the eye. Also look for a mostly dark rump on the Tree Swallow versus much more white on the flanks and rump of the Violet-Green. Soon, these beautiful dark blue birds will be feeding young and it's fun to watch Mom & Dad fly back and forth with food all day long to a hole in a tree or a box in your yard!"
--Mary Kiesau | Local Naturalist and Photographer
According to the Seattle Audubon Society In Washington, Tree Swallows are most likely to be confused with Violet-green Swallows, but Violet-green Swallows have white patches extending up the sides of the rump that can be seen in flight. The white on the faces of Violet-green Swallows extends above their eyes. Male and female Tree Swallows in adult plumage look similar to each other, but Tree Swallows are unique in that first-year females, although reproductively mature, have a different plumage from older birds. This plumage is similar to the juvenile plumage--non-iridescent brownish-gray above with a grayish-white belly. Juveniles have a grayish breast-band that first-year females lack. Juveniles could be mistaken for Bank Swallows, but the breast-band of Bank Swallows is more distinct than that of juvenile Tree Swallows.
Habitat
When nesting, Tree Swallows are usually found near water. They require nest cavities, either natural or man-made. Often these cavities are situated over or immediately adjacent to water.
Behavior
This social bird is often found in flocks. Tree Swallows are highly acrobatic and forage mostly in flight, often swooping low over open water or fields, sometimes skimming food items from the water's surface.
Diet
Flying insects make up most of the Tree Swallow's diet, although more than any other Washington swallow, the Tree Swallow eats berries and other vegetative matter when insects aren't flying. This allows the Tree Swallow to weather cold spells better than other swallows, which in turn allows it to winter farther north.
