The song of the Kauaʻi ʻōʻō, a bird native to Hawaii, is a delicate, flute-like melody. If you listen closely, you can hear a short succession of chirps gliding playfully from lower to higher tones.

NPR's Scott Detrow speaks with Matthew Medler of the Cornell Lab of Ornithology about the best bird sounds of 2025 from their vast collection of recordings, and why their selections made the list.

Part 1. 'I don't do calls' -- Crossing the sound barrier -- Tone and timpre -- Pitch and frequency -- Rhythm and timing -- Part 2. Put it all together and what have you got? -- Simple calls -- Simple ...