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DUSKY NIGHTJAR  Antrostomus saturatus 23–24cm. Medium-size, rather

dark nightjar of humid highland forest and edge, páramo, overgrown pastures;

local counterpart to whip-poor-wills. Hunts and sings mainly from snags and

low perches in trees. Note voice, elevation, dark plumage (varies from sooty to

dark rusty overall, belly usually spotted white to buff); no other nightjars likely

in same range and habitat, but overlap possible at lower elevations with

distinctive Pauraque. Also cf. Eastern Whip-poor-will. SOUNDS: Slow-paced,

burry tk, whiirr’p-wieh, every 1–11 secs, the introductory low tk audible only at

close range; suggests a medicated, asthmatic Eastern Whip-poor-will. Quiet

low growls when agitated. STATUS: Fairly common in highlands, mainly above 1500m in Northern Mts.,

above 1800m in Central and Talamanca Mts. (Costa Rica to w. Panama.)

EASTERN WHIP-POOR-WILL  Antrostomus vociferus 23–24cm. Poorly

known in Costa Rica, apparently rare. Medium-size, nonbr. migrant of forest

and edge habitats. Note relatively gray plumage with slightly paler and grayer

crown sides and scapulars, blackish median crown stripe, tail pattern; cf.

Chuck-will’s Widow, Dusky and Rufous Nightjars. SOUNDS: Rarely sings in

Costa Rica, but possible in spring migration, a whistled whie-pura-weén, every

1–1.2 secs or faster, lacks burry drawled quality of slower-paced Dusky Nightjar.

Flushed birds may give hollow clucks. STATUS: Scarce to rare Nov–Mar on

Pacific slope, to 1200m in Central Valley. (Breeds e. N America, winters s. to

Costa Rica.)

RUFOUS NIGHTJAR  Antrostomus rufus 26–28cm. Poorly known in Costa

Rica. Medium-large, rusty-toned nightjar of forest edge, second growth

woodland, adjacent semi-open areas and savannas with thickets. Roosts and

hunts from ground or low perches, including fence posts. Slightly smaller and

shorter-winged than Chuck-will’s-widow, with overall more rusty plumage (can

be grayed out by LED flashlights, and Chuck can be quite rusty), but silent

birds not easily separated in the field; note shorter white distal tail patches of

male, vs. white extending up to base of tail on Chuck. Beware that most other

nightjars can be bright rusty, especially Pauraque. SOUNDS: Song a fairly rapid-

paced, clipped whistled phrase, chük! wit-wit-weéo repeated steadily, every 1–2 secs. STATUS: Scarce and

local on both slopes, to 1000m; perhaps most frequent in foothills. (Costa Rica to S America.)

CHUCK-WILL’S-WIDOW  Antrostomus carolinensis 29–33cm. Large and big-

headed nonbr. migrant nightjar of varied wooded habitats from humid forest

and edge to second growth, plantations, mangroves. Roosts and hunts from

ground and perches, sometimes at mid–upper levels in trees. Note large size and

very long wings, overall warm brown plumage (some birds grayer) without

striking contrast except male tail pattern (from above shows only on spread tail).

Cf. Rufous Nightjar, Eastern Whip-poor-will. SOUNDS: Migrants sometimes

sing briefly in spring, usually for short periods around dawn and dusk, a rapid

chk weéu-weéu, 1st note inaudible at a distance. STATUS: Uncommon to scarce

Oct–Apr on both slopes, to 1500m. (Breeds e. US, winters to n. S America.)