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SWALLOW-TAILED KITE  Elanoides forficatus 56–61cm, WS 117–135cm.

Spectacular aerial raptor with long pointed wings and very long, deeply forked

tail; no similar species in Costa Rica. Breeds in humid forest, often near water.

Migrants occur widely over any open and forested habitats. Flight graceful and

buoyant with deep easy wingbeats and leisurely soaring, snatching insects from

canopy and on the wing; soars on flattish wings with tips curled up. Often in

pairs or small groups; flocks up to 50 or so during migration. 1st-year has shorter

tail than adult, white tips to primaries and primary coverts. Attains adult

appearance in 2nd year. SOUNDS: Shrill piping and ringing whistles, mainly in

flight, at times in rapid yelping series, accelerating and slowing, kleeh kleeh-kleeh-kleep and variations.

STATUS: Fairly common to uncommon breeder Jan–Aug locally on both slopes, mainly 100–1800m, a few

to 3000m; more widespread Aug–Sep, late Nov–Mar during migration; occasional in Oct to mid-Nov,

mainly on s. Pacific slope. (Breeds N America to S America, winters S America.)

WHITE-TAILED KITE  Elanus leucurus 38–41cm, WS 89–99cm. Distinctive

elegant raptor of open country with scattered trees, marshes, ranchland, even

towns. Note pointed wings, fairly long whitish tail, black shoulders. No really

similar species, but cf. male Northern Harrier (p. 114). Flies with easy wing­

beats, wings held in a shallow V during glides and infrequent soaring. Often

hovers and perches on roadside wires, like a kestrel. Attains adult appearance in

2nd year. SOUNDS: Mostly silent when not nesting. Varied low rasping notes, at

times paired with rising whistles; series of short, downslurred whistles, hüw,

hüw..., recalling Osprey. STATUS: Fairly common on both slopes, locally to

1500m. Expanding range with deforestation; first recorded Costa Rica in late

1950s. (Americas.)

MISSISSIPPI KITE  Ictinia mississippiensis 34–38cm, WS 84–94cm. Spring

and fall transient found widely in forested and semi-open country, often amid

much larger movements of Broad-winged and Swainson’s Hawks. Hunts in

flight like Plumbeous Kite; soars on flattish wings, the tips often curled up, tail

slightly spread; wingbeats languid and smooth. Confusion most likely with

Plumbeous Kite, which is darker overall, has rusty primary flashes (can be hard

to see); adult Plumbeous has white tail bands, lacks pale secondary panel on

upperwing; juv. has sparser dark brown (not rusty) streaking below. Also cf.

Peregrine Falcon. 1st-summer has mostly adult-like head and body, retains juv.

wings and tail. Attains adult appearance in 2nd year. Usually silent. STATUS: Fairly common to sporadically

common Sep–Oct, late Mar–early May on Caribbean slope, locally to 2700m, stragglers into Nov;

uncommon on Pacific slope and inland. (Breeds N America, winters S America.)

PLUMBEOUS KITE  Ictinia plumbea 33–37cm, 84–94cm. Dark aerial kite of

humid forest and edge, often near rivers; locally in mangroves. Highly aerial,

spends much time soaring and gliding; catches insects on the wing. Soars on

flattish wings, the tips often curled up, tail slightly spread; wingbeats languid

and smooth. Often perches high in trees adjacent to clearings and rivers. Cf.

paler Mississippi Kite, a later migrant in both spring and fall. SOUNDS: Mostly

quiet when not nesting. From perch and in flight, a high, plaintive, downslurred

whistle, typically preceded by a short overslurred note, si-hiiew; short piping

whistles. STATUS: Fairly common breeder Feb–Jul on both slopes, locally to

2000m; more widespread Jul–Sep, Jan–Mar during migration, rarely to 2700m, with early return

migrants rarely from late Dec. (Breeds Mexico to S America, winters S America.)