Rufous-tailed Tyrant
Knipolegus poecilurus
The rufous-tailed tyrant is 14.5 to 15 cm (5.7 to 5.9 in) long and weighs 13 to 15 g (0.46 to 0.53 oz). Adult males of the nominate subspecies K. p. poecilurus have a mostly grayish to brownish gray head and upperparts with a whitish throat. Their wings are dusky with buff edges on the inner remiges and buffy-gray tips on the coverts that show as two wing bars. Their tail is dusky with wide cinnamon edges on the inner webs that are conspicuous in flight. Their underparts are dull buffy gray or cinnamon-buff with a gray wash on the breast. Voice: The rufous-tailed tyrant is not highly vocal. Its call has been described as "a short, metallic trill, tzteeer or triiit", "high-pitched, raspy tzreeet notes followed by some jumbled notes", and "a dry, buzzy, descending dzeer a series of high peeps and a sharp, rising tip".
ID text from Wikipedia, CC BY-SA 4.0
Short-tailed Field Tyrant
Muscigralla brevicauda
The short-tailed field tyrant is 11 to 12 cm (4.3 to 4.7 in) long; two individuals weighed 13.5 and 11.8 g (0.48 and 0.42 oz). It has very long legs and a very short tail. The sexes have the same plumage. Adults have a brownish gray head with a short white patch above the lores and a mostly hidden yellow patch in the center of the crown. Their upperparts are mostly brownish gray with a buffy upper rump and rufous chestnut lower rump and uppertail coverts. Voice: One description of the short-tailed field tyrant's song is "a weak, sibilant tizztízzz, sometimes preceded by a few tik notes". Another is "a series of dry, metallic tik or spit notes followed by a buzzy, rising-falling trill: tik tik tik tzzZZZZzzew". Its calls include "a metallic, dry spit! and, when flushed, a sputtering trilled series of spit and trr notes".
ID text from Wikipedia, CC BY-SA 4.0

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Play today's Daily BirdPhotos and recordings are credited to their authors under the licence shown. Full profiles: Rufous-tailed Tyrant and Short-tailed Field Tyrant.