Tweeting 'bon voyage'

Have you ever thought about the annual journeys undertaken by birds across the planet? Today, to mark World Migratory Bird Day, we introduce the indigo bunting, a tiny bird with plumage like the twilight sky. They traverse thousands of kilometres using the stars to navigate. These birds migrate between their breeding grounds in North America and their wintering grounds in Central America and northern South America.
© Jeff R Clow/Getty Images