Asian Desert Warbler

Sylvia nana (Hemprich et Ehrenberg, 1833)

Пустынная славка | Шөл сандуғаш

Description

Adult Asian Desert Warbler in spring plumage has pale-sandy-brownish or buff-greyish upperparts. Flight feathers are brownish with pale edges which is narrow in primaries and broad in outer webs of secondaries. Uppertail is slightly rusty. Central tail feathers are buff-rusty, outer ones are white with brown spot on base of inner web; second outer pair is brown with whitish outer webs and tips; other tail feathers are dark-brown. Throat, breast and belly are off-white with brownish breast-flanks and buffy body-flanks. In fresh autumn plumage upperparts are more buffy; pale edges of flight and tail feathers become broader and more buffy. Juveniles in breeding plumage are slightly paler than adults. Legs are yellowish-grey, bill is yellow-horn, brownish on tip; eyes are whitish-yellow on adults and cloudy-yellow on juveniles. Sizes: male wing 54-61, tail 45-53, tarsus 17-19.5, bill 6.5-8.5 mm; female wing 53-57.5, tail 44.5-50.5, tarsus 17-19, bill 7-8 mm. Weight 7.9-10.1 gr.

Distribution

Asian Desert Warbler breeds and occurs on migration in southern half of Kazakhstan, north up to Volga-Ural sands, Dossor station, Karakum sands adjacent to Aral Sea and Chelkar-Teniz lake depression, northern Betpak-Dala, Taukum sands, lower current of Ile river, Ayaguz and Dzhungar “Gate”. Probably breeds in Alakol depression. In spring one bird observed in Zailiyskiy Alatau in Shubararcha.

Biology

Asian Desert Warbler is abundant, in places common breeding migrant. It inhabits hilly sands with rare shrubs (saxaul, tamarisk), clay deserts with spots of desert vegetations (saltwort, Calligonum sp., tamarisk, wormwood); on attitudes up to 500-700 m. On migration it occurs in edge of riparian forests, in bush thickets, man-made forests on plains and in foothills. In spring Asian Desert Warbler appears in March, or in early April. Breeding in separate pairs. Nest is built in bush from thin twigs, grass stems, leaves and bast; and is lined with vegetation fluff and some hair. Nest is built by both partners. Clutches of 4-6 eggs in April - early June. Both parents incubate and feed juveniles, which fledge in mid-May - June. Probably two broods per season, but it is not proved. Autumn migration begins early, in late July. Majority of birds leave in August - September, latest recorded in mid-end October.

Subspecies

Sylvia nana nana (Hemprich et Ehrenberg, 1833)

References

"Птицы Казахстана" том 4. "Наука", Алма-Ата. 1972. Gavrilov E. I., Gavrilov A. E. "The Birds of Kazakhstan". Almaty, 2005. Э.И.Гаврилов. "Фауна и распространение птиц Казахстана". Алматы, 1999.