Western Olivaceous Warbler

The Western Olivaceous Warbler, scientifically known as Iduna opaca, is a small passerine bird that bears a resemblance to a very pale Reed Warbler. It is a medium-sized warbler with a plain pale brown back and whitish underparts. The bill is robust and pointed, while the legs are a muted grey. The sexes appear identical, which is common among warblers. However, juveniles can be distinguished by a more buff-colored belly.

Identification Tips

When identifying the Western Olivaceous Warbler, look for its pale brown back and whitish underparts. The bird has a strong and pointed bill, which is larger than that of its relative, the Eastern Olivaceous Warbler. The legs are grey, and there is a browner tinge to the upperparts compared to its eastern counterpart.

Habitat

This species favors dry open country, which may include areas of cultivation with bushes or some trees. It is often found in low undergrowth or within a bush where it may construct its nest.

Distribution

The Western Olivaceous Warbler breeds in the Iberian Peninsula and North Africa. It is migratory, spending winters in sub-Saharan Africa. Occasionally, it is a rare vagrant to northern Europe.

Behaviour

The Western Olivaceous Warbler is known to be insectivorous like most warblers. It lays two to three eggs in a nest situated in low undergrowth or a bush.

Song & Calls

The song of the Western Olivaceous Warbler is a fast nasal babbling, which can be heard during the breeding season.

Breeding

Breeding occurs in Iberia and North Africa, where the bird lays two to three eggs in a nest in low undergrowth or a bush.

Similar Species

This warbler is larger and has a browner tinge to the upperparts than the Eastern Olivaceous Warbler, Iduna pallida. It also has a larger bill, which can be a distinguishing feature.

Diet and Feeding

As an insectivorous bird, the Western Olivaceous Warbler feeds on a variety of insects, which it typically forages for in low undergrowth or bushes.

Conservation status

The IUCN Red List has classified the Western Olivaceous Warbler as Least Concern, indicating that currently, there are no immediate threats to its population levels.