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COSTA RICAN PYGMY OWL  Glaucidium costaricanum 16–17cm. Very small

owl of highland oak forest and cloud forest; diurnal. See genus intro (p. 148).

Often sings from subcanopy; hunts low to high, at edges and in adjacent semi-

open areas. Only pygmy owl in most of its range; brown and rusty morphs both

frequent. Note voice, spotted crown (spots washed out in brightest rusty

morphs); cf. Ferruginous and Central American Pygmy Owls, mostly at lower

elevations. SOUNDS: Rapid hollow tooting, easily imitated. Varies from steady to

an irregular paired cadence (about 2 pairs/sec); typically 10 notes/3–3.5 secs.

Bouts of tooting often preceded by 1 or more rapid, slightly quavering

huhuhuhu phrases, with initial hooting bouts hesitant, shorter than later series. STATUS: Uncommon to

fairly common on both slopes; from timberline down to 1200m on Pacific slope, locally down to 900m

on Caribbean Slope. (Costa Rica to w. Panama).

BARE-SHANKED SCREECH OWL  Megascops clarkii 25–27cm. Rather dis­

tinctive large screech owl of cloud forest, elfin forest, and edge; nocturnal. Calls

mainly from canopy and subcanopy, but often hunts lower at edges and in

adjacent semi-open areas. Plumage brown to rusty overall. No similar species in

range and habitat: note large size, short ear tufts (head often looks rather

rounded), yellow eyes, cinnamon face, white-scalloped underparts; cf. Tropical

Screech Owl. SOUNDS: Song a short series of (usually 4–7) slow-paced low hoots

with slightly overslurred cadence, hu-ooo-ooo-ooo, every 3–10 secs; 1st and

sometimes last notes shorter and quieter. Agitated birds give wailing screams

that grade into triplets of strong hoots, faster-paced than song. STATUS: Uncommon to fairly common on

both slopes, above 900m in Northern Mts., above 1200m in Talamanca Mts. (Costa Rica to nw. Colombia).

UNSPOTTED SAW-WHET OWL  Aegolius ridgwayi 20–21.5cm. Small, com­

pact owl of highland oak forest and cloud forest; nocturnal. Sings from mid–

high levels, often well hidden; hunts from lower perches, sometimes along edges

of clearings. No visually similar species in Costa Rica: note big head, white

brows, plain underparts. Cf. slightly faster song of Costa Rican Pygmy Owl; saw-

whet toots tend to be hollower, slightly downslurred vs. overslurred in pygmy

owls. SOUNDS: Whistled tooting series, easily imitated, 10 notes/3.5–5 secs; toots

sometimes subtly grouped in series of 3–8 or so notes within protracted bouts of

hooting. Wailing screech, about 1 sec. STATUS: Scarce to uncommon on both

slopes, above 2400m. (Mexico to w. Panama.)

STRIPED OWL  Asio clamator 33–38cm. Savanna, oil palm plantations, ranch­

land, open country with scattered trees and thickets; roosts on ground and in

dense trees. Nocturnal; hunts from perches such as fence posts, roadside wires.

Flies with fairly shallow rapid wingbeats. Cf. Barn Owl. SOUNDS: Song a low,

moaning, overslurred hoóh, every 4–18 secs. Piercing, hawk-like, whistled scream,

keeer, about 0.5 sec, usually downslurred, sometimes in duet with hoots. Less often

(agitated?) a fairly rapid series of about 12–20 short clucks or yelping hoots, about

3/sec. STATUS: Uncommon to fairly common locally on both slopes to 1000m,

rarely to 1500m; may be spreading with deforestation. (Mexico to S America.)

BARN OWLS (TYTONIDAE; 1 SPECIES) Worldwide family of owls with

heart-shaped facial discs, relatively small eyes, short squared tails. Downy young molt directly

into adult-like plumage.

*BARN OWL  Tyto alba 36–41cm, WS 93–110cm. Widespread and distinctive

‘white owl’ of open and semi-open country with scattered trees, forest patches,

old buildings, towns; nocturnal. Often perches on roadside fence posts and

wires. Roosts in caves, buildings, tree hollows, dense palm crowns. Hunts main-

ly in flight, quartering over grassy areas with easy ‘floating’ wingbeats; often

hovers. Male averages whiter below than female. Cf. Striped Owl, often in same

areas. SOUNDS: Far-carrying rasping shriek, often given in flight; other shrieks

and hisses, none very heart-warming. STATUS: Uncommon to fairly common on

both slopes, locally to 1800m. (Worldwide.)