Gray Wren-Warbler Calamonastes simplex Scientific name definitions

13 cm; 12 g. A rather long-legged, dark grey warbler that habitually waves its long, dark tail. Has grey-brown face with narrow white shaft streaks, dark grey-brown crown and upperparts ; upperwing-coverts edged paler brown, marginal coverts at wrist mottled brown and white; tail blackish-brown, darker than rump, faintly barred and with narrow whitish tip; lead-grey below, sometimes faintly barred whitish on chin, upper throat and lower central belly ; undertail-coverts grey-brown with narrow white tips; underwing-coverts white with brown subterminal bands; eyes reddish-brown; bill black; legs pinkish-brown. Differs from C. undosus in much darker and greyer plumage, only faint barring below (on belly and chin), tail darker than rump. Sexes alike. Juvenile has pale buff margins on upperwing-coverts, paler underparts with faint barring on belly and flanks; bill brown.

SE South Sudan, Ethiopia, Djibouti, N and S Somalia, Kenya, E Uganda and N Tanzania.

Confined to Somali-Masai biome; inhabits dense undergrowth in dry woodland and acacia (Acacia) scrub in arid and semi-arid savannas, to 1500 m.

Little known; presumably mostly resident.

Diet mainly insects. Forages low down in bushes and trees, usually below 1 m, as well as on the ground. Almost all foraging takes place inside bushes and small trees, with only 9% at outer edges. In Tsavo (Kenya), gleans most prey from twigs and stems (51%), with 33% from leaves, 15% from ground, and 3% taken in the air. Frequently raises and lowers tail slowly, often while held partly fanned; raised to c. 45 degrees, but not cocked vertically.

Male song a loud, penetrating “clack clack ” or “click click” like sound of two stones hitting together, repeated monotonously at 1–1·2 notes per second; sometimes slightly buzzy “zi-ink zi-ink zi-ink…”; snaps bill sharply with each note. Song may also be 2-note “click clack”; stretches body up on first note, then drops sharply with second note.

Breeds Nov–May. Probably monogamous; solitary, territorial. Male displays to female during nest-building by fanning tail while calling and by making short flight over nest-site. Nest built mainly by one member of pair (presumably female), a large oval structure with side entrance at top, supported by vertical stems, and covered with living leaves stitched together, lined with fine fibrous plant material, situated c. 0·3 m above ground in small leafy shrub. Clutch 3–4 eggs; no information on incubation and nestling periods.

Not globally threatened. Locally common.