From Opus

Photo by mehdhalaouate
Marrakech, south-western Morocco, July 2005

Iduna opaca

[edit] Identification

Total length 15 cm (6 in). 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.

[edit] Similar species

Slightly larger, heavier-billed and browner than Eastern Olivaceous Warbler.

[edit] Distribution

Breeds in Spain and north-western Africa from Western Sahara to north-western Libya. Winters in western Africa (mainly in the Sahel zone). Leave breeding grounds in July-October and return in March-April (North West Africa) or May (Spain).

[edit] Taxonomy

This is a monotypic species.
It was formerly considered conspecific with Eastern Olivaceous Warbler and included in the genus Hippolais.

A Birdforum discussion includes statements that subspecies reiseri is vocally distinct from both opaca and elaeica^[4].

[edit] 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.

[edit] Behaviour

When foraging, the eastern races flick their closed tail up-and-down; a habit lacking in the western race.

[edit] Diet

Feeds on insects and spiders. To lesser extend also fruits. Generally feeds at high levels, but sometimes lower on migration.

[edit] 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.

[edit] References

1. 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
2. Clements, JF. 2010. The Clements Checklist of Birds of the World. 6th ed., with updates to December 2010. Ithaca: Cornell Univ. Press. ISBN 978-0801445019. Spreadsheet available at http://www.birds.cornell.edu/clementschecklist/Clements%206.5.xls/view
3. Gill, F, M Wright and D Donsker. 2009. IOC World Bird Names (version 2.0). Available at http://www.worldbirdnames.org/.
4. Birdforum thread with links to pictures of different forms of Olivaceous Warbler

[edit] External Links