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PEARL KITE Gampsonyx swainsonii 22–26cm, WS 45–55cm. Handsome,
very small raptor of open and semi-open country, especially ranchland with
scattered trees. Often perches on roadside wires, isolated trees; hunts from
perch and in flight while soaring. Distinctive: note small size, pointed wings,
dark cap contrasting with pale buffy forehead and cheeks, short dark bar at
breast sides, rusty flanks. Imm. has narrow pale edgings to crown and back; like
adult in 2nd year. SOUNDS: High piping whistles, often in steady series, pieh-
pieh...; downslurred whistle followed by short rippling series, pseeu, pi-pi-pi-pi-
pi. STATUS: Uncommon to rare but increasing, mainly on Pacific slope, locally
on Caribbean slope and inland to 2100m; first recorded Costa Rica in mid-1990s, and spreading with
deforestation. (Nicaragua to S America.)
FALCONS
(12+ species; forest falcons on p. 130, caracaras p. 144). Fairly diverse, worldwide family
of raptors; genetic studies indicate falcons share a common ancestor with parrots, but traditionally they
have been grouped with hawks as ‘birds of prey,’ as done here for ID purposes. Ages differ, sexes similar
or different (female often noticeably larger); like adult in 2nd year.
AMERICAN KESTREL Falco sparverius 26–29cm, WS 61–65cm. Attractive,
lightly built, small migrant falcon of varied open and semi-open habitats with
trees and scattered bushes, from farmland and open woodland to wetlands and
rural areas. Distinctive: all plumages have complex head pattern, long rusty tail,
overall pale underwings. Often seen perched on roadside wires and utility poles.
Wingbeats rather loose and floppy, not strong and purposeful like Merlin; soars
on flattish wings, often hangs in wind and hovers. Juv. male has whiter breast,
heavier black spotting than adult. SOUNDS: Mostly silent; high shrill screaming
kyieh-kyieh..., usually in short bursts, repeated. STATUS: Uncommon to fairly
common Oct–Apr on both slopes, to 1800m, rarely higher; winters mainly in Pacific lowlands and
interior, more widespread Sep–Oct, Mar–Apr. (Americas.)
MERLIN Falco columbarius 27–32cm, WS 64–70cm. Small, dashing migrant
falcon of varied open and semi-open habitats, from ranchland and forest
clearings to wetlands and coastal lagoons. Generally rather dark; all plumages
have blackish tail with narrow whitish to pale gray bars, overall dark underwings.
Cf. Bat Falcon, much larger Peregrine Falcon. Perches on fence posts, utility
poles, in trees; rarely on wires, unlike kestrel. Wingbeats quick and powerful,
hunting flight usually low and fast; soars on flattish wings; does not hover.
Imm. brownish above, much like female. SOUNDS: Mostly quiet; high screaming
kriih-kriih..., in interactions, with quality suggesting Killdeer. STATUS: Scarce to
uncommon Oct–Apr throughout; mainly in coastal lowlands, but rarely to 3000m. (Holarctic; winters in
New World to S America.)
BAT FALCON Falco rufigularis 23–28cm, WS 61–73cm. Handsome small
falcon of lowland forest and edge, adjacent clearings and semi-open areas with
taller trees; locally in towns. Distinctive: dark overall with white to buffy throat,
rusty thighs, but cf. Merlin, larger Peregrine Falcon. Typically perches con
spicuously on bare snags, antennas, often in pairs, when size difference between
sexes readily apparent (female larger). Flight fast and powerful, chasing birds,
bats, insects, and dive-bombing larger raptors; soars on flattish wings, at times
high overhead, when can be mistaken for White-collared Swift (p. 234). Throat
and neck variably washed buff, on some birds strongly cinnamon. Imm. washed
brownish overall, with dark throat streaks, barring on thighs and undertail coverts. SOUNDS: Penetrating,
at times persistent screaming often draws attention to birds perched and in flight: slower-paced krieh
krieh…and rapid hew-hew...; single sharp kik. STATUS: Uncommon on both slopes, locally to 2200m,
rarely higher. (Mexico to S America.)