• Summary
• Text account
• Data table and detailed info
• Distribution map
• Reference and further resources

Taxonomic note
Iduna opaca (del Hoyo and Collar 2016) was previously listed as Hippolais opaca.

Taxonomic source(s)
AERC TAC. 2003. AERC TAC Checklist of bird taxa occurring in Western Palearctic region, 15th Draft. Available at: #http://www.aerc.eu/DOCS/Bird_taxa_of _the_WP15.xls#.
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A., Fishpool, L.D.C., Boesman, P. and Kirwan, G.M. 2016. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 2: Passerines. Lynx Edicions and BirdLife International, Barcelona, Spain and Cambridge, UK.
Ottosson, U.; Bensch, S.; Svensson, L.; Waldenström, J. 2005. Differentiation and phylogeny of the olivaceous warbler Hippolais pallida species complex. Journal of Ornithology 146: 127-136.

Population justification: The global population size has not been quantified, but the species is reported to be locally common (BirdLife International 2004). The European population is estimated at 5,200 pairs, which equates to 10,400 mature individuals (BirdLife International 2015). However Europe only forms c.10% of the global range. It is described as 'rather common' within much of its North African range (Svensson and Christie 2013).

Trend justification: The European population is estimated to be decreasing by less than 25% in 12 years (three generations) (BirdLife International 2015).

Recommended citation
BirdLife International (2023) Species factsheet: Iduna opaca. Downloaded from http://datazone.birdlife.org/species/factsheet/isabelline-warbler-iduna-opaca on 04/12/2023.
Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from http://datazone.birdlife.org on 04/12/2023.