Chilean Swallow
Tachycineta leucopyga
The Chilean swallow is about 13 centimetres (5.1 in) in length and weighs 15–20 grams (0.53–0.71 oz). It is glossy blue-black above and white below with a white rump. Its wings and tail are black, with white tips on its inner secondaries and its tertials. Their underwing coverts and auxiliaries are both grey. The Chilean swallow's bill and legs are black. The sexes are alike, and the juveniles are duller and browner. It is similar to the white-rumped swallow, but lacks the white forehead of that species and has bluer upperparts and grey underwing-coverts.
ID text from Wikipedia, CC BY-SA 4.0
Tree Swallow
Tachycineta bicolor
The tree swallow has a length between about 12 and 14 cm (4.7 and 5.5 in) and a weight of approximately 17 to 25.5 g (0.60 to 0.90 oz). Wingspan ranges from 30 to 35 cm (12 to 14 in). The male has mostly glossy blue-green upperparts, the wings and tail being blackish. The underparts and the cheek patch are white, although the underwing coverts are gray-brown. The bill is black, the eyes dark brown, and the legs and feet pale brown. The female is duller in color than the male, and sometimes has a brown forehead. Voice: The tree swallow's song consists of three parts: the chirp, the whine, and the gurgle. These sections may be repeated or omitted, and all can stand alone.
ID text from Wikipedia, CC BY-SA 4.0
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