tags: Tree Swallow, Tachycineta bicolor, birds, mystery bird, bird ID quiz
[Mystery bird] Tree Swallow, Tachycineta bicolor, photographed at Lake Thompson in Kingsbury County, South Dakota. [I will identify this bird for you tomorrow]
Image: Terry Sohl, 2 May 2009 [larger view]
Photo taken with a Canon 50D, 400 5.6L.
Please name at least one field mark that supports your identification.
Tree swallow, based on the coloring and the lack of white over the eye (which the violet-green would have). Pretty!