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GENUS CHAETURA (4 species). Widespread, taxonomically vexed New World genus of small swifts

with stiff shaft spines projecting on tail tip (visible with good views); throat and rump variably paler than

rest of dark sooty plumage. Often in small groups, typically flying lower than Cypseloides swifts, often not

much higher than treetops; associate readily with swallows. Rapid, at times almost fluttering wingbeats

interspersed with brief glides; soar less often than Cypseloides. Nest in hollow trees, buildings.

CHIMNEY SWIFT  Chaetura pelagica 12–12.5cm; WS 30–32.5cm. Transient

migrant over Caribbean lowlands and adjacent foothills, especially near the

coast. Often in loose groups, typically with a focused heading: southeast in fall,

northwest in spring. Flight strong and fast with rapid wingbeats and only brief

gliding; soars only occasionally, unlike larger swifts. Mixes with feeding groups

of Hellmayr’s Swift, when larger size and slower, stronger wingbeats of Chimney

can be appreciated, but plumage rather similar. SOUNDS: Usually silent; high

sharp chips and short twitters rarely in interactions, fuller and mellower than

Hellmayr’s and Richmond’s Swifts. STATUS:  Sporadically fairly common to

common Oct–early Nov, mid-Mar to Apr on Caribbean slope, especially near coast; rarely to 1500m.

(Breeds e. N America, winters S America.)

*RICHMOND’S [VAUX’S] SWIFT  Chaetura [vauxi] richmondi 10.5–11cm;

WS 25–27.5cm. Common small swift of highlands and foothills, foraging over

varied habitats from forest and towns to pastures and lakes. See genus note. Not

easily told from Hellmayr’s Swift of Caribbean lowlands but throat typically pal-

er and more contrasting whereas rump typically duller and browner. Lacks con-

trasting pale rump patch of Costa Rican Swift. Cf. larger, longer-winged Chim-

ney Swift. Wing molt mainly May–Sep? SOUNDS: High thin chips and twitters,

including an accelerating, overall descending tsi-tsi-si-sirr; higher and shriller than

Chimney Swift. STATUS: Fairly common locally on both slopes, mainly 700–

2000m, at times to 3000m and (mainly in rainy weather) down to coastal lowlands. (Mexico to Panama.)

*HELLMAYR’S [GRAY-RUMPED] SWIFT  Chaetura [cinereiventris] phaeopygos

10.5–11cm, WS 25–27cm. Common small swift of humid Caribbean

lowlands, where replaces Richmond’s Swift of higher elevations; ranges over

forested and open habitats, rivers. See genus note. From Richmond’s Swift by

duller throat, grayer and more contrastingly pale rump. Cf. Chimney Swift,

which is larger and longer winged, evident in direct comparison. Costa Rican

Swift does not overlap in range, differs in smaller and brighter rump patch.

Wing molt mainly Jun–Oct? SOUNDS: High single sharp chips and twitters,

relatively shrill and thin. STATUS: Fairly common locally on Caribbean slope, to

1000m. (Honduras to Panama.)

COSTA RICAN [BAND-RUMPED] SWIFT  Chaetura [spinicauda] fumosa

10.5–11cm, WS 25–27.5cm. Distinctive small swift of humid Pacific lowlands,

ranging over forested and open habitats, rivers. See genus note. From below

difficult to distinguish from Richmond’s Swift, but has more restricted pale

throat area; from above note distinctive, strongly contrasting pale rump patch.

Wing molt mainly Mar–Jul? SOUNDS: High sharp chips and twitters, lower and

richer than Richmond’s (and Hellmayr’s). STATUS: Fairly common locally on s.

Pacific slope, to 1500m. (Costa Rica to w. Panama.)

LESSER SWALLOW-TAILED SWIFT  Panyptila cayennensis 12.5–14cm; WS

29–31cm. Distinctive and handsome small swift of humid lowlands, over

forest, adjacent semi-open areas, water bodies. Singles or small groups associate

readily with flocks of Chaetura but also fly higher and separate. Flight very fast

with flickering wingbeats, short glides, tail usually closed in a point. No similar

species in Costa Rica. Nest a long funnel (up to 1m long) of plant down and

spider webs attached to side of large trunk or rock face, entrance at bottom.

SOUNDS: Thin reedy chips and twitters; short, slightly explosive speeez, fading

abruptly. STATUS: Uncommon to fairly common locally on both slopes, to

1000m; rarely to Central Valley. (Mexico to S America.)