An unusual nesting habit for Swiftlets

Abstract

Swiftlets typically nest on rock walls or roofs of cavities and caves - possibly this helps to reduce predation. Two species - Mountain Swiftlet (Collacalia hirundinacea) and White-rumped Swiftlet (C. spodiopygius) are known to sometimes nest on cave floors in PNG. Possible reasons for this in relation to predators is discussed.