Western Olivaceous Warbler
Encyclopedia
The Western Olivaceous Warbler, also known as Isabelline Warbler, (Hippolais opaca) is a "warbler", formerly placed in the Old World warbler
s when these were a paraphyletic wastebin taxon
. It is now considered a member of the acrocephaline warblers, Acrocephalidae
, in the tree warbler
genus Hippolais . It was formerly regarded as part of a wider "Olivaceous Warbler" species, but as a result of modern taxonomic developments, this species is now usually considered to be two species:
It is a small passerine
bird
, found in dry open country, including cultivation, with bushes or some trees. 2-3 eggs are laid in a nest in low in undergrowth or a bush. Like most warblers, Western Olivaceous is insectivorous.
It is a medium-sized warbler, more like a very pale Reed Warbler
than its relative the Melodious Warbler
. The adults have a plain pale brown back and whitish underparts. The bill is strong and pointed and the legs grey. The sexes are identical, as with most warblers, but young birds are more buff on the belly. It has a characteristic downward tail flick.
Western Olivaceous Warbler breeds in Iberia
and north Africa
. It is migratory
, wintering in sub-Sahara
n Africa
. It is a rare vagrant to northern Europe.
Western Olivaceous Warbler is larger and has a browner tinge to the upperparts than Eastern Olivaceous Warbler. It also has a larger bill. The song is a fast nasal babbling.
Old World warbler
The "Old World Warblers" is the name used to describe a large group of birds formerly grouped together in the bird family Sylviidae. The family held over 400 species in over 70 genera, and were the source of much taxonomic confusion. Two families were split out initially, the cisticolas into...
s when these were a paraphyletic wastebin taxon
Wastebin taxon
Wastebasket taxon is a term used in some taxonomic circles to refer to a taxon that has the sole purpose of classifying organisms that do not fit anywhere else. They are typically defined by their lack of one or more distinct character states or by their not belonging to one or more other taxa...
. It is now considered a member of the acrocephaline warblers, Acrocephalidae
Acrocephalidae
Acrocephalidae is a family of oscine passerine birds, in the superfamily Sylvioidea....
, in the tree warbler
Tree warbler
Tree warblers are medium-sized warblers belonging to the genus Hippolais, formerly placed in the "Old World warbler" family Sylviidae but now separated in the marsh- and tree-warbler family Acrocephalidae. They are found in Europe, Africa and western Asia....
genus Hippolais . It was formerly regarded as part of a wider "Olivaceous Warbler" species, but as a result of modern taxonomic developments, this species is now usually considered to be two species:
- Western Olivaceous Warbler, Hippolais opaca, and
- Eastern Olivaceous WarblerEastern Olivaceous WarblerThe Eastern Olivaceous Warbler is a "warbler", formerly placed in the Old World warblers when these were a paraphyletic wastebin taxon. It is now considered a member of the acrocephaline warbelrs, Acrocephalidae, in the tree warbler genus Hippolais ...
, Hippolais pallida
It is a small passerine
Passerine
A passerine is a bird of the order Passeriformes, which includes more than half of all bird species. Sometimes known as perching birds or, less accurately, as songbirds, the passerines form one of the most diverse terrestrial vertebrate orders: with over 5,000 identified species, it has roughly...
bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
, found in dry open country, including cultivation, with bushes or some trees. 2-3 eggs are laid in a nest in low in undergrowth or a bush. Like most warblers, Western Olivaceous is insectivorous.
It is a medium-sized warbler, more like a very pale Reed Warbler
Reed Warbler
The Eurasian Reed Warbler, or just Reed Warbler, Acrocephalus scirpaceus, is an Old World warbler in the genus Acrocephalus. It breeds across Europe into temperate western Asia. It is migratory, wintering in sub-Saharan Africa....
than its relative the Melodious Warbler
Melodious Warbler
The Melodious Warbler is an Old World warbler in the tree warbler genus Hippolais. It breeds in southwest Europe and northwest Africa. It is migratory, wintering in sub-Saharan Africa....
. The adults have a plain pale brown back and whitish underparts. The bill is strong and pointed and the legs grey. The sexes are identical, as with most warblers, but young birds are more buff on the belly. It has a characteristic downward tail flick.
Western Olivaceous Warbler breeds in Iberia
Iberian Peninsula
The Iberian Peninsula , sometimes called Iberia, is located in the extreme southwest of Europe and includes the modern-day sovereign states of Spain, Portugal and Andorra, as well as the British Overseas Territory of Gibraltar...
and north Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
. It is migratory
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
, wintering in sub-Sahara
Sahara
The Sahara is the world's second largest desert, after Antarctica. At over , it covers most of Northern Africa, making it almost as large as Europe or the United States. The Sahara stretches from the Red Sea, including parts of the Mediterranean coasts, to the outskirts of the Atlantic Ocean...
n Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
. It is a rare vagrant to northern Europe.
Western Olivaceous Warbler is larger and has a browner tinge to the upperparts than Eastern Olivaceous Warbler. It also has a larger bill. The song is a fast nasal babbling.