Blackpoll Warblers make one of the longest migrations taken by a songbird in the world. Blackpoll Warblers that breed in Alaska fly southeast in the fall, appearing throughout the Midwest and eastern U.S. on their way to the Atlantic Coast. Then, they make a nonstop flight over the water to reach South America. Scientists uncovered the stranger-than-fiction details of Blackpoll Warbler migration thanks to a tool called a light-level geolocator, which uses day length to figure out where a bird traveled.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.