Orange-billed Sparrow
Arremon aurantiirostris
The orange-billed sparrow is 14.5 to 16.5 cm (5.7 to 6.5 in) long and weighs about 35 g (1.2 oz). The sexes have the same plumage and all subspecies have the eponymous bright orange bill. Adults of the nominate subspecies A. a. aurantiirostris have a black crown with a gray stripe along its middle and a wide white supercilium on an otherwise black face. Their upperparts are olive-green and their wings and tail a darker olive-green with yellow at the bend of the wing. Their chin has a small black area and their throat is white with a wide black band below it across the upper upper breast. Voice: The orange-billed sparrow's song varies geographically though in general is "high-pitched, either a series of alternating lilting notes or thin whistles". In northern Central America it is an "extremely high-pitched series of sharp whistles" that lasts about two seconds; its call there is a "smacking tsiit!".
ID text from Wikipedia, CC BY-SA 4.0

Pectoral Sparrow
Arremon taciturnus
The pectoral sparrow is sexually dimorphic, and, as the name implies, sparrow-sized, at 15 cm (5.9 in) in length and 24 g (0.85 oz) in weight. Its upperparts are pale green, becoming yellow near the bend of the wing. The head is black, with white on its throat and as stripes on its crown. Its underparts are white in males and creamy in females, with males also having a broad black band going across its breast (a pectoral band). The beak is also black, roughly 14–15 mm (0.55–0.59 in) long for both males and females. Tails are 58–60 and 64–67 mm (2.3–2.4 and 2.5–2. Voice: The song of the pectoral sparrow is a high-pitched buzz, consisting of very short tzik notes (initial tzik note may be slightly faster, and lower in pitch.) and usually followed by 2-4 longer, almost identical tzzzzzz notes. The entire song lasts for 2–3 seconds, at a pitch of 8 kilohertz.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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Play today's Daily BirdPhotos and recordings are credited to their authors under the licence shown. Full profiles: Orange-billed Sparrow and Pectoral Sparrow.