In the main lower section of the Gomanton cave in Sabah, Borneo, a bird's nest collector climbs a 500-foot rattan rope ladder to reach the upper walls. This is where brown-rumped, edible-nest swiftlets weave their nests from saliva, which adheres to the surface of the rock.The nests are highly regarded in Chinese cuisine, although almost tasteless, and can be cooked in several ways, but most typically as bird's nest soup..