Adults: Above, light olive-grey to dark brown-olive. Rump and base of tail, buff-yellow to yellow-olive. Wings and tail, darker grey-brown, with a black subterminal band and grey-white tip on all but the central pair of feathers. Forehead and cheeks, scalloped and flecked pale to deep cream. Below, uniformly cream-white to deep cream-buff washed and flecked olive-grey, more so on flanks. Eye, cream-white. Bill, dusky black. Feet, black.
Derivation
Ac-anth-iz'-a - Gk, acantheon, thorny brake; Gk, zao, I live: iredalei, - Tom Iredale (b. 1880), English ornithologist and secretary to Gregory Mathews, 1909 - 23
Habitat
Low, dense saltbush, bluebush. Cottonbush. Samphire on saltlakes, saltmarshes. Low banksia, tea-tree, casuarina scrubs, sand-plain heaths. Mulga and other acacias. Mangroves.
There are two apparently isolated populations. The population found in the South-East of South Australia and in Western Victoria is in low (<2m) heathland. The much larger population North and West of Adelaide (to the coast of Western Australia) is found in even lower vegetation (<0.5m), often in Samphire. Close to Adelaide this species is not uncommon on tidal samphire flats.
Slender-billed Thornbill (Acanthiza iredalei) [XC40757]
by Eddy Smith from Port Gawler, SA, Australia (song)
Slender-billed Thornbill (Acanthiza iredalei) [XC756156]
by id from Port Gawler, Adelaide Plains Council, South Australia, Australia (song)
Nest
Domed, composed of grass and plant-dowm. Usually in a low shrub.
Eggs (Guide)
3; white, speckled with red-brown at the larger end; oblong-oval; about 15 x 11 mm.
Young
Altricial, nidicolous.
Subspecies
Possibly closest to Buff-rumped Thornbill (Acanthiza reguloides). Probably forms a superspecies with Buff-rumped Thornbill (Acanthiza reguloides) and Western Thornbill (Acanthiza inornata). However, recent analysis of mitochondrial DNA suggests that present species may be closer to Chestnut-rumped Thornbill (Acanthiza uropygialis). Further study is required.
The following 3 subspecies are recognised:
iredalei Mathews, 1911 - The arid and semi-arid regions of South Australia and western Australia.
rosinae Mathews, 1913 - From St Kilda to Ardrossan, Gulf St Vincent, South Australia.
hedleyi Mathews, 1912 - Big and Little Deserts, Victoria, and Ninety Mile Plain, South Australia.
The Field Guide to the Birds of Australia Pizzey, G., and Knight, E., 1997, Angus & Robertson, Sydney ISBN 0 207 19691 5
Field Guide to Australian Birds Morecombe, M., 2000, Steve Parish Publishing Pty Ltd. ISBN 1 876282 10 X
Field Guide to the Birds of Australia Simpson, K., and Day, N., 1999, 6th Edition, Viking ISBN 0 670 87918 5
Reader's Digest Complete Book of Australian Birds 1988, 2nd Edition, Reader's Digest ISBN 0 949819 99 9
What Bird is That? 1984, Revised Edition, Angus & Robertson, Sydney ISBN 0 207 14846 5
Handbook of Australian, New Zealand & Antarctic Birds 1990 - , Oxford University Press, Melbourne ISBN 0 19 553244 9
BirdLife International Species Factsheet