Plain Swift Apus unicolor


Justification of Red List Category
Although this species may have a restricted range, it is not believed to 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 is not known, but the population is not believed to be decreasing sufficiently rapidly to approach the thresholds under the population trend criterion (>30% decline over ten years or three generations). The population size may be small, but it is not believed to 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
The breeding population, which is confined to Europe, is estimated to number 7,500-20,000 pairs, which equates to 15,000-40,000 mature individuals and 22,500-60,000 individuals in total (BirdLife International 2015).

Trend justification
The trend for the European breeding population is unknown (BirdLife International 2015).


The species uses sea cliffs and is never found very far from the sea. It occurs over all habitats in Canaries from sea-level to 2,500 m; especially common in deep coastal gulleys. On Madeira it occurs from sea-level to the highest summit, Pico Ruivo, breeding on rocky islets. It breeds between March and August and lays two eggs. It nests in a variety of natural sites, such as caves and cliffs, where suitable rock niches occur, or under tiles or in holes in man-made structures. The saucer-shaped nest is constructed largely from downy seed cases with other plant matter or man-made items less frequently incorporated, agglutinated with saliva with occasional feathers adhered to surface. It feeds on insects. Numbers are reduced in winter on the Canary Islands; migrants probably winter mainly in north-west Africa, as there are winter records from Mauritania and northern Morocco for the species there (Chantler and Boesman 2014), with a recent breeding record reported from Morocco too (Aourir et al. 2017).


There are currently no known threats to this species.

Conservation actions

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

Conservation Actions Proposed
No conservation measures are currently required for this species.


Text account compilers
Ashpole, J, Ekstrom, J., Butchart, S., Symes, A., Westrip, J.

Recommended citation
BirdLife International (2020) Species factsheet: Apus unicolor. Downloaded from on 24/02/2020. Recommended citation for factsheets for more than one species: BirdLife International (2020) IUCN Red List for birds. Downloaded from on 24/02/2020.