American Kestrel
Falco sparverius
Under traditional terminology, the American kestrel is the smallest raptor in the Americas, though the South American spot-winged falconet is almost as small. The American kestrel is sexually dimorphic, although there is some overlap in plumage coloration between the sexes. The bird ranges from 22 to 31 cm (8.7 to 12.2 in) in length with a wingspan of 51–61 cm (20–24 in). The female kestrel is larger than the male, though less so than larger falcons, being typically about 10% to 15% larger within a subspecies. Voice: The American kestrel has three basic vocalizations – the "klee" or "killy", the "whine", and the "chitter". The "klee" is usually delivered as a rapid series – klee, klee, klee, klee when the kestrel is upset or excited. This call is used in a wide variety of situations and is heard from both sexes, but the larger females typically have lower-pitched voices than the males.
ID text from Wikipedia, CC BY-SA 4.0
Merlin
Falco columbarius
The merlin is 24–33 cm (9.4–13.0 in) long with a 50–73 cm (20–29 in) wingspan. Compared with most other small falcons, it is more robust and heavily built. Males average at about 165 g (5.8 oz) and females are typically about 230 g (8.1 oz). There is considerable variation, however, throughout the birds' range and—in particular in migratory populations—over the course of a year. Thus, adult males may weigh 125–210 g (4.4–7.4 oz), and females 190–300 g (6.7–10.6 oz). Each wing measures 18.2–23.8 cm (7.2–9.4 in), the tail measures 12.7–18.5 cm (5.0–7.3 in) and the tarsus measures 3.7 cm (1.
ID text from Wikipedia, CC BY-SA 4.0
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