Short-crested Flycatcher
Myiarchus ferox
The short-crested flycatcher is about 18 cm (7.1 in) long and weighs 21 to 34 g (0.74 to 1.2 oz). The sexes have the same plumage. Adults of the nominate subspecies M. f. ferox have a smoky brown crown and upperparts; the crown has a slight crest. Their face is otherwise gray. Their wings are mostly dark brown with whitish yellow to grayish outer webs on the tertials. The wing's greater and median coverts have wide paler fuscous brown tips that show as two wing bars. Their tail is dark smoky brown with rufous edges on the feathers that quickly wear away. Voice: The short-crested flycatcher's song, given both at dawn and during the day, is "hort, slowly vibrato-modulated whistles given infrequently". It has also been described as a "short, fine prrrrih trill". Its calls include "rasping whistles, hiccups, and sometimes strident rattles".
ID text from Wikipedia, CC BY-SA 4.0
Yellow-crowned Tyrannulet
Tyrannulus elatus
The yellow-crowned tyrannulet is 10 to 11 cm (3.9 to 4.3 in) long and weighs 6.5 to 8 g (0.23 to 0.28 oz). Adult males have a slate-gray to dark brown or blackish crown with a bright yellow to orange-yellow stripe along its middle. Their nape and back are bright olive-green. They have a grayish supercilium, a thin dark line through the eye, and a pale gray lower face. Their wings are dusky with two white to yellowish white bars. Their tail is dusky olive. Their throat is pale gray and their underparts pale to medium yellow with an olive wash on the breast. Voice: The yellow-crowned tyrannulet's song is a "2-noted, clear, plaintive 'wih-weér' (or 'free beer'), 2nd note higher, shorter, and stressed". It apparently differs little across the species' range.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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