Before revision: alt=Brazil star trails and birds in light pollution photography in Rio beach at night|249x249px|Brazil star trails and birds in light pollution photography in Rio beach at night alt=Birds flying trace and star trail near Rio de Janeiro beach at night time in light pollution|248x248px| jBirds flying trace and star trail near Rio de Janeiro beach at night time in light pollution Birds migrate at night for several reasons.
After revision: alt=Brazil star trails and birds in light pollution photography in Rio beach at night|249x249px|Brazil star trails and birds in light pollution photography in Rio beach at night alt=Birds flying trace and star trail near Rio de Janeiro beach at night time in light pollution|248x248px| Birds flying trace and star trail near Rio de Janeiro beach at night time in light pollution Birds migrate at night for several reasons.