Barn Swallow
Hirundo rustica
The adult male barn swallow of the nominate subspecies H. r. rustica is 17–19 cm (6+1⁄2–7+1⁄2 in) long including 2–7 cm (1–3 in) of elongated outer tail feathers. It has a wingspan of 32–34.5 cm (12+1⁄2–13+1⁄2 in) and weighs 16–22 g (9⁄16–3⁄4 oz). It has steel blue upperparts and a rufous forehead, chin and throat, which are separated from the off-white underparts by a broad dark blue breast band. The outer tail feathers are elongated, giving the distinctive deeply forked "swallow tail". There is a line of white spots across the outer end of the upper tail. Voice: Males sing to defend small territories (when living in colonies, less so in solitary pairs) and to attract mates. Males sing throughout the breeding season, from late April into August in many parts of the range. Their song is made up of a "twitter warble," followed by a rising "P-syllable" in European H. r. rustica and the North American H. r. erythrogaster.
ID text from Wikipedia, CC BY-SA 4.0
Pacific Swallow
Hirundo javanica
This species is a small swallow at 13 cm (5.1 in) in length. It has a blue-black back and crown with browner wings and tail, a red face and throat, and dusky underparts. It differs from the barn swallow and the closely related welcome swallow in its shorter and less forked tail.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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