Cassin's Kingbird
Tyrannus vociferans
Adults have a gray head with slightly darker cheeks; a dark unforked tail with a buffy fringe and gray-olive underparts. They have a pale throat and deep yellow lower breast. Juveniles are duller and have pale edges on their wings. Measurements: Length: 8.3–9.1 in (21–23 cm) Weight: 1.6 oz (45 g) Wingspan: 41 cm Cassin's kingbird and the western kingbird are similar in appearance. Cassin's is a little larger than the western and the upper parts are a darker gray than the western.
ID text from Wikipedia, CC BY-SA 4.0
Eastern Kingbird
Tyrannus tyrannus
Adults are grey-black on the upperparts with light underparts; they have a long black tail with a white end and long, pointed wings. They have a red patch on their crown, seldom seen. They are of average size for a kingbird, at 19–23 cm (7.5–9.1 in), 33–38 cm (13–15 in) across the wings and weighing 33–55 g (1.2–1.9 oz). The call is a high-pitched, buzzing and unmusical chirp, frequently compared to an electric fence.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
Learn this pair in BeakBrain
Photo and call practice, free in any browser.
Play BeakBrainPhotos and recordings are credited to their authors under the licence shown. Full profiles: Cassin's Kingbird and Eastern Kingbird.