172
CUCKOOS (CUCULIDAE; 10+ SPECIES) Worldwide, notably diverse family found
mainly in warmer climates; most species rather long-tailed, all have 2 toes pointing forward, 2
backward. Ages similar or different, attaining adult appearance in 1st year; sexes similar.
YELLOW-BILLED CUCKOO Coccyzus americanus 28–30.5cm. Nonbr.
migrant to varied wooded, forested, and scrubby habitats, including hedgerows,
coastal scrub, humid forest edge, mangroves. Forages low to high: hops and peers
about in foliage for caterpillars, other invertebrates; often sluggish and easily
overlooked. Flight fast and direct, often slipping into cover and vanishing. Note
clean white underparts, big white tail spots, bright rusty flash in wings, bright
yellow on bill; cf. Black-billed and Mangrove Cuckoos. Juv. has less contrasting
tail pattern than adult. Typically silent in Costa Rica. STATUS: Fairly common to
uncommon Sep–Nov, Apr–May, mainly in lowlands and foothills; rare in winter,
mainly on Pacific slope. (Breeds N America and Mexico, winters S America.)
BLACK-BILLED CUCKOO Coccyzus erythropthalmus 27.5–30cm. Transient
migrant in varied wooded and forested habitats from humid forest to coastal
scrub, mangroves. Habits like Yellow-billed Cuckoo, and thus easily overlooked
and infrequently encountered. Note dingy whitish underparts, weak pattern on
underside of tail, dark bill. Cf. Yellow-billed and Mangrove Cuckoos. Typically
silent in Costa Rica. STATUS: Uncommon Sep–Nov, Apr–May, mainly in
lowlands and foothills. (Breeds N America, winters S America.)
MANGROVE CUCKOO Coccyzus minor 30.5–33cm. Handsome cuckoo of
dry forest and edge, gallery forest, second growth, semi-open areas with taller
trees, mangroves. Habits much like Yellow-billed Cuckoo. Like most cuckoos,
often suns itself in early morning, at times on exposed branches. Note buff
underparts, dark mask, big white tail spots, bright yellow on bill; cf. Yellow-
billed Cuckoo. Juv. has less contrasting tail pattern. SOUNDS: Mostly silent
unless breeding. Song a typically accelerating series of harsh croaks, 6–9 secs,
ending with an abrupt switch to a quieter short series of lower coos, AHRR,
AHRR, AHRR-AAHR-AAHR...owh-owh...; sometimes preceded by quiet dry
rattle of 1–2 secs. STATUS: Uncommon Nov–May on Pacific slope, scarce on Caribbean slope, to 1500m;
scarce and local Jun–Oct, and may breed along Pacific coast. (Mexico to n. S America.)
GROOVE-BILLED ANI Crotophaga sulcirostris 30.5–34.5cm. The common
and widespread ani in most of Costa Rica, found in open and semi-open
habitats, from ranchland to forest edge, often around livestock. Social, usually
in small groups. Perches on wires, hops readily on ground, clambers in foliage,
long tail often loosely flopped about. Flight distinctive: rapid flaps interspersed
with flat-winged glides, one bird following another across a field or road; often
crash-lands into foliage. Bill shape and habits distinctive, except for very local
overlap with slightly larger Smooth-billed Ani (which see), often best separated
by voice. SOUNDS: Common call a squeaky pí-chwiep or pí-weérp, emphasis on
1st note, often in short series. Other varied piping, squealing, and growling noises. STATUS: Fairly common
to common on both slopes to 1500m, locally inland to 2000m; absent from s. Pacific lowlands, where
replaced by Smooth-billed Ani. (Mexico to S America.)
SMOOTH-BILLED ANI Crotophaga ani 33–37cm. Replaces Groove-billed Ani
on s. Pacific slope. Habits much like Groove-billed but flight a little stronger.
Slightly larger than Groove-billed (noticeable in direct comparison), but often
best detected and identified by voice. Also note more raised culmen of Smooth-
billed (especially male), smooth bill sides (can be hard to see, and juv. Groove-
billed has smooth bill, lacking grooves for a few months after fledging).
SOUNDS: Slurred squealing whistles, distinct from Groove-billed Ani, typically
reeéah or wheeéreh, can suggest a hawk. Other squealing, mewing, and clucking
sounds. STATUS: Fairly common to common on s. Pacific slope, to 1200m; may
be spreading north. (Caribbean region to S America.)