380
*OLIVE SPARROW Arremonops rufivirgatus 13.5–14.5cm. Rather drab sparrow
of dry lowland forest, adjacent thickets, gallery forest. In pairs or family groups
scratching in leaf litter, rarely ranging into fruiting bushes; sings from concealed
perch at low to mid-levels in shady understory. No similar species in Costa Rican
range: note drab, overall rather plain plumage with distinct dark stripes on buffy
head. Juv. duller overall with dark streaking above and below, weak head pattern;
soon like adult. SOUNDS: High, sharp, slightly smacking tsik, can be repeated
steadily. Song a variably accelerating series of twangy to ringing chips, mostly
4–6 secs; starts with 2–5 slower-paced notes often different in quality from main
song series, such as tk, siu, s’wee tseu tseu-tseutseu…or tk, tik seeu, si sweeu chi-chi-chichi.…STATUS: Fairly
common on n. Pacific slope, locally to 900m in w. Central Valley. (Mexico and s. Texas to Costa Rica.)
BLACK-STRIPED SPARROW Arremonops conirostris 16–17.5cm. Fairly large
and bulky sparrow of humid lowland forest edge, second growth thickets,
overgrown fields, hedgerows, gardens. In pairs or family groups, mostly on or
near ground, but ranges into fruiting bushes and trees, at times into subcanopy;
sings mainly from low to mid-levels in shady understory. Distinctive in range,
with bold black stripes on gray head, olive upperparts. SOUNDS: Downslurred
mellow cheu and slightly gruff cheuh, both often repeated steadily. High lisping
notes and twangy nasal duets when excited. Song prolonged, up to 45 secs or
more: begins with hesitant rich twangy chirps and burry whistles every 1–2 secs
then runs into an accelerating series of nasal chuh and choo notes that fade out or run into a roll, such as
h’uit, cheuhr, húit, cheuk, cheu...choo choo choo choo-choo-choochoo...; sometimes ends with abrupt nasal
cheúh. STATUS: Fairly common on both slopes, to 1500m. (Honduras to S America.)
CABANIS’S GROUND SPARROW Melozone cabanisi 15–16.5cm. Attractive
and distinctively patterned sparrow of humid foothill woodland and plantations,
adjacent second growth, brushy hedgerows, overgrown fields. Mostly retiring,
in shady understory; pairs forage on ground in leaf litter, ranging to adjacent
open edges mainly early and late in day. No similar species in Costa Rica: note
bright rusty cap, complex head and breast pattern. SOUNDS: Rather quiet, high
thin ti and stronger, harder tik. Song a short medley of 2–4 downslurred, often
inflected whistled notes preceded by 1–3 short chips, such as tik-tik ssiiu p’ssiuu
or tk ssiiu ti’p’ssiu, and variations, 1–1.5 secs. STATUS: Uncommon to fairly
common but local, mainly in hills around Central Valley, 600–1600m.
(Endemic to Costa Rica.)
*WHITE-EARED GROUND SPARROW Melozone leucotis 17.5–18.5cm.
Fairly large, attractively patterned sparrow of humid foothill woodland and
plantations, adjacent second growth. Mostly retiring, in shady understory; pairs
forage on ground, often scratching noisily in leaf litter. No similar species in
Costa Rica: note bold head pattern, with white face patches, yellow collar.
SOUNDS: High thin ti; high sibilant twitters in pulsating duet, up to about 5
secs. Song a staccato series of (usually 5–11) slightly sibilant ringing chips, often
accelerating slightly, and preceded by 2–3 high slurred chips, such as ti siu si
chi-chi-chi-chi-chichi, 2–2.5 secs. STATUS: Fairly common to uncommon from
n. Pacific slope s. to Central Valley, 500–2000m; spills over locally to adjacent Caribbean slope. (Mexico
to Costa Rica.)