Most of the bird sounds you hear on BirdNote come from the Macaulay Library, a vast collection of over one million bird calls and songs curated by the Cornell Lab of Ornithology. The library relies on both professional field recordists and dedicated volunteers to capture the sounds of birds all over the world.More info and transcript at BirdNote.org. Want more BirdNote? Subscribe to our weekly newsletter. Sign up for BirdNote+ to get ad-free listening and other perks. BirdNote is a nonprofit. Your tax-deductible gift makes these shows possible.