Justification of Red List Category
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be stable, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
In Europe, the breeding population is estimated to number 4,370,000-8,020,000 pairs, which equates to 8,740,000-16,000,000 mature individuals (BirdLife International 2015). Europe forms >50% of the global range, so a very preliminary estimate of the global population size is 17,480,000-32,000,000 mature individuals, although further validation of this estimate is needed.
This population is suspected to be stable overall, with the European population trend stable between 1982 and 2013 (EBCC 2015).
In western Europe the species is usually found in semi-open, mixed broadleaf woodlands and plantations, riverine forests with tall willows (Salix) and poplars (Populus), forested steppes, groves, copses, orchards, parks, large gardens, windbreaks, avenue trees, and other tree clumps in cultivated areas. It also occurs in larger and more continuous deciduous, coniferous or mixed forests in eastern Europe. In Asia it is found in floodplain woods and groves, riverine vegetation, open deciduous woods, village plantations, taiga edges and oases, to 2,150 m. In the African non-breeding quarters, it uses semi-arid to humid deciduous woodlands, e.g. miombo (Brachystegia) and mopane (Colophospermum), forest edges, tall closed-canopy gallery forest, riverine acacias (Acacia), forest-savanna mosaics, tree savannas, exotic plantations, windbreaks, orchards and gardens, up to 1,500 m (Walther and Jones 2008). Eggs are laid mainly in May and June and the nest is built by the female only, although the male may collect some material. The nest is a shallow to deep open-cup structure woven from grass, sedges, reeds, leaves, twigs, cloth, string, paper and plastic strips, strips of bark and other plant fibres and then lined with fine fibres, roots and grasses, feathers, cocoons, cobweb, down, cotton, fur, wool, moss, lichens, straw and small pieces of paper. It is suspended hammock-like in thin, horizontal forked branch, typically high in outer edge of well-foliaged tree canopy. Clutches are usually three to five eggs. Its diet is mainly small invertebrates and fruits but it occasionally consumes seeds, nectar, pollen and rarely, small lizards, small mammals, eggs and nestlings (Walther and Jones 2008). The species is migratory, wintering in the climatically temperate, equatorial African high woodlands and moist montane forests of East Africa (Hagemeijer and Blair 1997).
Brood size can be severely affected by weather conditions which may cause large, short-term fluctuations in the population at regional or supra-regional level. The species is persecuted in Greece (Hagemeijer and Blair 1997), as they consume large quantities of fruit and are thus considered a pest by some fruit-farmers (Walther and Jones 2008). In the U.K., the loss of large poplar plantations has led to the decline of the species there (Holling and the Rare Birds Breeding Panel 2007). In addition, climate change may pose a threat in the future (Mason and Allsop 2009).
Conservation Actions Underway
Bern Convention Appendix II. The species occurs in many protected areas throughout its breeding range (Walther and Jones 2008).
Conservation Actions Proposed
In the U.K., the restoration of areas of poplar woodland of at least 30 ha with plenty of woodland edges is recommended for the conservation of this species (Milwright 1998). The impact of persecution should be assessed and legislation introduced to minimise this.
Text account compilers
Ashpole, J, Ekstrom, J., Butchart, S., Symes, A.
BirdLife International (2020) Species factsheet: Oriolus oriolus. Downloaded from http://www.birdlife.org on 10/07/2020. Recommended citation for factsheets for more than one species: BirdLife International (2020) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 10/07/2020.