LC
Spotless Starling Sturnus unicolor



Justification

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 increasing, 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.

Population justification
In Europe, the breeding population is estimated to number 23,900,000-30,600,000 pairs, which equates to 47,800,000-61,300,000 mature individuals (BirdLife International 2015). Europe forms c.55% of the global range, so a very preliminary estimate of the global population size is 87,000,000-111,000,000 mature individuals, although further validation of this estimate is needed.

Trend justification
The population is suspected to be increasing due to an expansion of the species's range in Iberia (Feare and Craig 1998). In Europe, trends between 1998 and 2013 show that populations have undergone a moderate increase (EBCC 2015).

Ecology

This species is found in open woodland with expanses of short grass, often in association with grazing mammals as well as in farmland, parks, gardens and cities. Breeding occurs from April to mid-July in Spain and March to July in Morocco. It is a colonial nester. Both sexes build the nest, mainly from dry grass and it is lined with grass, roots, leaves and feathers. Often yellow flowers are included in the structure, as well as fresh green leaves. It is placed in a natural hole or an old woodpecker hole, or in the disused burrow of European Bee-eater (Merops apiaster) or Collared Sand Martin (Riparia riparia) and artificial structures and nestboxes are widely used. Clutches are four to five eggs in Spain. It is omnivorous; it takes mainly animal matter in the spring and summer and fruit and seeds in the autumn and winter. The species is mostly sedentary (Craig et al. 2015).

Threats

Interbreeding between this species and Sturnus vulgaris has been observed in areas where it is sympatric (Hagemeijer and Blair 1997), although this is not known to be a serious threat.

Conservation actions

Conservation Actions Underway
Bern Convention Appendix II. There are currently no known conservation measures for this species within Europe.

Conservation Actions Proposed
No conservation measures are currently needed for this species within Europe.

Acknowledgements

Text account compilers
Ashpole, J, Butchart, S., Ekstrom, J.


Recommended citation
BirdLife International (2023) Species factsheet: Sturnus unicolor. Downloaded from http://www.birdlife.org on 30/03/2023. Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 30/03/2023.