In Cave Swiftlets: Masters of Echolocation, narrator Sir David Attenborough introduces cave swiftlets, birds that, like bats, use echolocation to navigate the dark caves of Borneo. Cave swiftlets rely on clicks to find their way through pitch-black cave passages and locate their small nesting sites. Their nests, made entirely of saliva, take 30 days to build. For centuries, people have harvested these nests, which are the key ingredient in the valuable delicacy, bird’s nest soup. This video is excerpted from BBC’s Planet Earth, a breathtaking documentary series that highlights the natural wonders of our planet.
In Cave Swiftlets: Masters of Echolocation, narrator Sir David Attenborough introduces cave swiftlets, birds that, like bats, use echolocation to navigate the dark caves of Borneo. Cave swiftlets rely on clicks to find their way through pitch-black cave passages and locate their small nesting sites. Their nests, made entirely of saliva, take 30 days to build. For centuries, people have harvested these nests, which are the key ingredient in the valuable delicacy, bird’s nest soup. This video is excerpted from BBC’s Planet Earth, a breathtaking documentary series that highlights the natural wonders of our planet.