The migration of birds, such as the pelicans seen here over California"s Salton Sea, is part of the pulse of our planet"s ecosystem. Around 40% of bird species migrate, typically in the fall and spring, some traveling incredible distances. Tiny hummingbirds can migrate 500 miles across the Gulf of Mexico overnight. Arctic terns fly between the Arctic and Antarctic each year, potentially racking up more than 1.5 million miles over a lifetime. The bar-tailed godwit can travel 7,000 miles in eight days, without stopping. On World Migratory Bird Day, we can help our feathered friends by protecting their habitats and taking simple steps like leaving less lights on at night, leaving out birdseed, and making windows more visible to avoid collisions.