 The Himalayan swiftlet has a twittering ' roosting call, and also has a piercing ' call.What distinguishes many, but not all, swiftlet species from other swifts and indeed almost all other birds (the oilbird being an exception) is their ability to use a simple but effective form of echolocation to navigate through the darkness of the caves where they roost at night and breed.With the present species, at least "vulcanorum" is known to echolocate.