Aplomado Falcon
Falco femoralis
The aplomado falcon is very slender, long-winged, and long-tailed, the size of a small peregrine falcon (F. peregrinus), at 30–40 cm (12–16 in) long and with an average wingspan of about 90 cm (35 in), but only half the weight, at about 208–305 g (7.3–10.8 oz) in males and 270–460 g (9.5–16.2 oz) in females. In adult birds, the upperparts are dark blue-grey, as is much of the head, with the usual falcon "moustache" contrasting sharply with the white throat and eyestripe.
ID text from Wikipedia, CC BY-SA 4.0
Bat Falcon
Falco rufigularis
The bat falcon is 23 to 30 cm (9.1 to 12 in) long. Males weigh 108 to 150 g (3.8 to 5.3 oz) and have a wingspan of 51 to 58 cm (20 to 23 in). Females weigh 177 to 242 g (6.2 to 8.5 oz) and have a wingspan of 65 to 67 cm (26 to 26 in). They have long wings and a longish tail with a square tip. The sexes have similar plumage. Adults have blue-black head and upperparts with grayish edges on the feathers from the upper back to the uppertail coverts. Voice: The bat falcon is vocal "in breeding season, especially near nest, in contacts with other raptors, and even when attacking prey." Its main call is a "rapid shrill screaming" kee-kee-kee.. or kew-kew-kew..; the male's is higher pitched than the female's. Other calls include "an even higher and thinner "tsee-tsee-tsee...
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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