Alternative name: Isabelline Warbler
- Iduna opaca
Identification
Total length 13.5-15 cm, weight 9-17 g
Bill rather long and forehead "flat". Tail relatively long and square-endeed (sides rounded). Primary extention ca. ½ tertial-length. Dull greyish-brown above, whitish below with a dull greyish-brown tinge to flanks and chest. Eye-ring, lores and poorly marked supercilium buffy-white. Upper mandible blackish, lower dull orange-yellow.
Similar species
Slightly larger, heavier-billed and browner than Eastern Olivaceous Warbler.
Distribution
Breeds in Spain and northwestern Africa north of the Atlas Mountains, from Western Sahara to north-western Libya. Winters in western Africa, mainly in the Sahel zone. Leave breeding grounds in July to October and returns in March or April (northwest Africa) or May (Spain).
Taxonomy
This is a monotypic species.
It was formerly considered conspecific with Eastern Olivaceous Warbler, and was, along with the other species of Iduna, included in the genus Hippolais.
A Birdforum discussion includes statements that the Eastern Olivaceous Warbler subspecies I. p. reiseri is vocally distinct from both Western Olivaceous and I. p. elaeica[4].
Habitat
Wide range of wooded and brushy habitats. Prefers areas with some tall trees and dense undergrowth, but avoids closed forest. Often near water. Fairly common in most of its range, but more scarce in Spain.
Behaviour
When foraging, does not flick its closed tail up-and-down, unlike Eastern Olivaceous Warbler.
Diet
Feeds on insects and spiders. To lesser extend also fruits. Generally feeds at high levels, but sometimes lower on migration.
Breeding
The nest is a cup made of plant-material placed fairly low in the fork of a branch. The 3-5 eggs are incubated by the female, but both parents feed the nestlings.
References
- Dickinson, EC, ed. 2003. The Howard and Moore Complete Checklist of the Birds of the World. 3rd ed., with updates to October 2008 (Corrigenda 8). Princeton: Princeton Univ. Press. ISBN 978-0691117010
- Clements, J. F., T. S. Schulenberg, M. J. Iliff, S. M. Billerman, T. A. Fredericks, B. L. Sullivan, and C. L. Wood. 2019. The eBird/Clements Checklist of Birds of the World: v2019. Downloaded from http://www.birds.cornell.edu/clementschecklist/download/
- Gill, F, M Wright and D Donsker. 2009. IOC World Bird Names (version 2.0). Available at http://www.worldbirdnames.org/.
- Birdforum thread with links to pictures of different forms of Olivaceous Warbler
Recommended Citation
- BirdForum Opus contributors. (2024) Western Olivaceous Warbler. In: BirdForum, the forum for wild birds and birding. Retrieved 26 April 2024 from https://www.birdforum.net/opus/Western_Olivaceous_Warbler
