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Sulawesi Swiftlet - BirdForum Opus

Aerodramus sororum


A small Swiftlet (10cm), very similar to Uniform Swiftlet (especially) and Glossy Swiftlet and difficult to identify in the field.

  • upperparts black-brown
  • rump band distinct and grey-white
  • underparts pale-brown
  • tail forked
  • In hand: extensively white rami on rump feathers


Sulawesi endemic. South East Asia: Indonesia: Greater Sundas. Common in parts of its range.

Sight records from Taliabu islands probably this species, while sight records from Sangihe and Siau may refer to Sulawesi Swiftlet, or to Halmahera Swiftlet.


This is a monotypic species.
It was formerly included in Moluccan Swiftlet, together with Halmahera Swiftlet and Seram Swiftlet.

Forms a superspecies with the two latter species and Philippine Swiftlet, Mountain Swiftlet, White-rumped Swiftlet and Australian Swiftlet. Also considered to be conspecific with White-rumped Swiftlet. Relationships in this group are still poorly understood. Like other Aerodramus Swiftlets this species is often placed in Collocalia.


Moist lowland forest and montanes. Generally higher than other Swiftlets.


Feeds on insects, taken in flight. Noted to feed above canopy while Glossy Swiftlet is feeding beneath canopy level.
Not much information about nesting. Believed to make a nest with vegetable matter, attached to a cave wall.
Thought to be resident or nomadic within range.


  1. Clements, J. F., P. C. Rasmussen, T. S. Schulenberg, M. J. Iliff, T. A. Fredericks, J. A. Gerbracht, D. Lepage, A. Spencer, S. M. Billerman, B. L. Sullivan, and C. L. Wood. 2023. The eBird/Clements checklist of Birds of the World: v2023. Downloaded from https://www.birds.cornell.edu/clementschecklist/download/
  2. Gill, F, D Donsker, and P Rasmussen (Eds). 2023. IOC World Bird List (v 13.2). Doi 10.14344/IOC.ML.13.2. http://www.worldbirdnames.org/

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