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SWIFTS (APODIDAE; 10 SPECIES) Worldwide family of supreme aerialists, only

seen perched at roosts and nests, which tend to be in caves, behind waterfalls, other

inaccessible places. Ages/sexes similar in most species, different in a few; adult appearance

attained in about 1 year.

CHESTNUT-COLLARED SWIFT  Streptoprocne rutile 12.5–14cm; WS 30.5–

33cm. Mainly foothills and highlands; nests in caves and rocky gorges. Usually in

groups of 10–100 birds, associating readily with Chaetura and other swifts. Flight

recalls Chaetura but stronger, less fluttery, with more frequent gliding; note longer

tail (distinctly notched on male) than Chaetura, more scimitar-like wings, voice;

chestnut collar diagnostic when present (lacking on 1st-year and some females).

SOUNDS: Dry buzzy crackling notes and chatters; suggests electricity crackling in

power lines; occasional screechy notes thrown in. STATUS: Fairly common, mainly

1000–2500m but ranges locally to coastal lowlands. (Mexico to S America.)

WHITE-COLLARED SWIFT  Streptoprocne zonaris 20–21.5cm; WS 48.5–

53cm. Wide-ranging, spectacular large swift; nests colonially in caves, often near

waterfalls. Feeds low to high, at times sweeping past at head height when wings

make strong rushing sound; soars frequently, wings spread in paddle-like bulges.

Usually in groups, locally 100s, from dispersed feeding bands to tightly

synchronized screaming squadrons that wheel high overhead. Note large size,

broad white collar, forked tail. 1st-year has white hindcollar, weak whitish scaling

across upper neck. In poor light, cf. Black Swift, Bat Falcon. SOUNDS: Loud

screaming and screeching chatters can suggest parakeets. STATUS: Fairly common

to common; breeds locally in mountains, ranges widely to lowlands. (Mexico to S America.)

GENUS CYPSELOIDES (3 species). ‘Terrestrial’ equivalent to storm petrels, breeding at scattered

colony sites and ranging widely to feed; thus could be encountered anywhere in the country. Black and

White-chinned routinely commute long distances daily, as from mountains to coastal lowlands. Cypseloides

often feed much higher overhead than Chaetura and are easily overlooked unless flying lower near roost sites,

or brought low by rainy weather. ID challenging, and many birds often best left unidentified to species.

BLACK SWIFT  Cypseloides niger 14–18cm; WS 36–42cm. Breeds in highlands, often behind waterfalls;

ranges over varied habitats, at times in flocks; associates with other swifts when feeding. Wingbeats strong,

not hurried; often soars and glides. Note size (bigger than Chestnut-collared Swift, smaller than White-

collared), broad-based, sickle-like wings; in some lights shows striking frosty whitish forehead. Male has

forked tail. N American migrants average larger than Costa Rican breeding birds. SOUNDS: Fairly hard

dry chips, usually in short series, chi-chi-chi-chit, not harsh or buzzy. STATUS: Local breeder Apr–Sep in

highlands, ranging to foothills and lowlands; winter status in Costa Rica unclear. Uncommon migrant

Sep–Oct, Apr–May, mainly on Pacific slope. (Breeds w. N America to Panama, winters S America.)

*WHITE-CHINNED SWIFT  Cypseloides cryptus 14–15cm; WS 33–35.5cm. Breeds in highlands, often

around waterfalls; ranges over varied habitats, at times in flocks, and associates with other swifts when

feeding. Slightly larger, chunkier than Chestnut-collared Swift, with bigger head, squared tail. Stockier,

less sickle-winged than Black Swift, but longer-winged and longer-tailed, less compact than Spot-fronted

Swift. Wingbeats rapid, direct flight heavy-bodied, but soars readily. White chin can be distinct when

throat is full of food, but cf. Black Swift, which also can show whitish chin when throat is full. Some birds

(imms.? females?) have whitish mottling on belly or whitish vent band. SOUNDS: Sharp buzzy chips and

chatters; slightly more shrieking, less ‘electric’ than Chestnut-collared Swift. STATUS: Uncommon to scarce

resident; potentially wide-ranging. (Honduras to S America.)

SPOT-FRONTED SWIFT  Cypseloides cherriei 12.5–13.5cm, WS 30.5–32.5cm. Breeds in highlands

and foothills, often around waterfalls; ranges over varied habitats, often in small groups. Associates with

other swifts, especially Chestnut-collared. Similar size to Chestnut-collared Swift but chunkier, with

bigger head, shorter squared tail. Wingbeats rapid, direct flight heavy-bodied, but soars readily, at least

for short periods. In good light, white ‘headlight’ spots can be striking, postocular spot usually less so.

SOUNDS: High sharp chips often accelerate into rhythmic, slightly buzzy phrases, tchip, tchip chípi-chípi-

chirr-chirr, chípi-chípi-chirr-chirr.…STATUS: Uncommon to scarce resident; perhaps mainly in Pacific slope

foothills. (Costa Rica to S America.)