We make it a habit to detail the broad and beautiful spectrum of bird colors, but iridescent feathers are undoubtedly among the most mesmerizing. When sunlight hits the Bufflehead’s dark head feathers at the right angle, their colors transform into shades of the rainbow, from deep violet to green and gold. Common Grackles, caught in natural light, gleam gold, green and blue-purple. Starlings, too. And the dull gray Rock Pigeons shuffling around a city park might reveal a glimpse of the electric teal and lavender, shifting shades on their throat.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.