Data Zone
Justification of Red List category
This species has an extremely large range and the population size may be moderately small to large, but it is not believed to approach the thresholds for Vulnerable under the population size criterion. Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion. For these reasons the species is evaluated as Least Concern.
Population justification
In Europe, the total population size is estimated at 21,500-47,700 mature individuals, with 10,700-23,900 breeding pairs (BirdLife International 2021), and comprises approximately 90% of the species' global range, so a very preliminary estimate of the global population size is between 23,900-53,000 mature individuals, although further validation of this estimate is desirable. The species' population in Europe is considered to have undergone a small decline over three generations (10 years) (BirdLife International 2021). As this region holds the vast majority of the species' global range, the global population size is considered to be decreasing slowly over three generations.
Trend justification
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This species inhabits orchards of almond (Prunus dulcis), olive (Olea) and pistachio (Pistacia vera), open oak (Quercus) woods, maquis on mountain slopes, savanna-like open woods and sparse trees on grassland, and similar. The presence of some taller trees is preferred. Breeding occurs from May to June. The nest is a well-built, deep cup of grasses, plant stems and soft twigs, often covered with cobwebs and lined with fine fibres, plant down, fur and similar soft material. It is sited in the fork of a branch of a tree. Clutches are three or four eggs. It is thought to mainly feed on insects and other invertebrates, and in the summer it also takes fruits and berries, including figs (Ficus). The species is migratory, wintering in southern Africa (Svensson 2006).
The ecology of this species is not well known, however it may be threatened by changes in habitat structure, especially from clearance and thinning of woodland and agricultural intensification in olive-groves and fruit plantations. Agricultural pesticide use may decrease insect prey numbers. In addition, bird trapping in Greece may impact the species (Tucker and Heath 1994).
Conservation Actions Underway
CMS Appendix II. Bern Convention Appendix II. EU Birds Directive Annex I. There are currently no known conservation measures for this species within Europe.
Conservation Actions Proposed
Due to economic and cultural factors, the habitat of this species is likely to remain non-threatened, although it is essential that funding to assist olive production should favour old traditional plantations and management. Studies should look at the impact of the intensification of agriculture and forestry and the use of broad spectrum pesticides should be avoided. A survey of the species’s population status is needed, as well as research on its ecological requirements (Tucker and Heath 1994).
Text account compilers
Rutherford, C.A., Martin, R.
Recommended citation
BirdLife International (2024) Species factsheet: Olive-tree Warbler Hippolais olivetorum. Downloaded from
https://datazone.birdlife.org/species/factsheet/olive-tree-warbler-hippolais-olivetorum on 23/11/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 23/11/2024.