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*PLAIN WREN Cantorchilus modestus 12.5–14.5cm. Attractive wren of over
grown weedy fields, second growth, forest edge, especially with bamboo, grassy
tangles. Mostly skulking at low to mid-levels, often in dense grassy vegetation,
but at times ranges up into more open subcanopy. Note bold white eyebrow,
plain pale grayish face and breast, bright buffy-cinnamon to buffy-brown
flanks, unbarred undertail coverts. Comprises 3 groups often treated as 2 or
3 species: Cabanis’s Wren C. [m.] modestus (12.5–13.5cm) on n. Pacific
slope, averages darker, less rusty-toned, and with weaker dark tail barring than
slightly paler Isthmian Wren C. [m.] elutus (12.5–13.5cm) of s. Pacific slope.
Canebrake Wren C. [m.] zeledoni (13.5–14.5cm) of Caribbean slope averages
largest and darkest, with grayer upperparts, duller flanks, stronger dark tail
barring than Cabanis’s. Juv. Cabanis’s and Isthmian duller overall than adults;
juv. Canebrake averages brighter, with buffier flanks suggesting Cabanis’s.
SOUNDS: Varied song of short, rich whistled phrases usually repeated quickly a
few times, often with a lisping introductory note, such as ss ti-been ti-been...;
longer and more complex in duets. Also much higher, thin whistled phrases
with rippling cadence, such as tsi-pii-siip every few secs. Song of Isthmian may
average mellower, slower-paced, than Cabanis’s but often not separable; song of
Canebrake averages lower-pitched. Calls include a dry, slightly scratchy cht,
often doubled and repeated steadily when scolding. Isthmian scold of accel
erating staccato tiks run into dry trill, tik-tik-t-trrrrrrr perhaps distinct from
Cabanis’s. Canebrake scold a dry staccato chatter, slowing toward the end.
STATUS: Fairly common to common, but distribution details of the 3 groups in
need of elucidation, especially on the cen. Pacific slope and n. Caribbean slope:
Cabanis’s occurs on n. Pacific Slope, to 2000m, locally on adjacent n. Carib
bean slope (Mexico to Costa Rica); Isthmian on s. Pacific slope (Costa Rica to
Panama); Canebrake on Caribbean slope, to 1700m, where reportedly hybrid
izes in foothills with Cabanis’s (Nicaragua to nw. Panama).
RIVERSIDE WREN Cantorchilus semibadius 12.5–13.5cm. Handsome wren
of dense vegetation bordering streams and swampy areas in humid forest,
second-growth thickets. Mainly low in tangles, probing in dead-leaf clusters
and vines. No similar species in range: note barred underparts, strong barring
on wings and tail. Juv. duller, less distinctly patterned overall; soon like adult.
SOUNDS: Song of (usually 2–3) rich ringing whistles, 0.5–1 sec, often repeated
2–10× in rapid series, such as seé-chu-we, seé-chu-we..., less often single songs
every few secs; longer and more complex in duets. Songs of Isthmian Wren less
rich, typically higher, quicker-paced, often with more notes. Calls include rich
abrupt h’weet; sharply overslurred, ringing ch’lieh, and quiet, nasal whistled pee’tee’chih, all may be repeated
steadily; harsh clicks and low rasping chatter, zzzeh-zzzeh…when scolding. STATUS: Fairly common to
common on s. Pacific slope, to 1200m. (Costa Rica to w. Panama.)
BLACK-BELLIED WREN Pheugopedius fasciatoventris 14.5–15.5cm. Rela
tively large, bulky, and distinctive wren of Heliconia and other second-growth
thickets at lowland forest edge, streamsides, overgrown plantations. At low to
mid-levels, often in large-leaved plants, hanging dead leaves. Note bold white
bib, blackish cheeks and belly; cf. Bicolored Antbird (p. 268). Juv. duller overall
with dingier throat and breast; soon like adult. SOUNDS: Song of (usually 4–7)
rich, slightly hollow, often slurred whistles, such as to-wee hu-tchu-hu, 1–1.5
secs, often relatively long pauses between songs, which are usually given singly,
not in rapid series; longer and more complex in duets. Calls include distinctive
clipped rasp paired with mellow whistle, zhhk-whéu, can be repeated steadily; varied short hollow whistles;
and low rasping churrs. STATUS: Fairly common on s. Pacific slope, to 500m. (Costa Rica to w. Colombia.)
Isthmian
Canebrake
Cabanis’s