Roughly the size and shape of a Mourning Dove, North America_—Ès littlest falcon packs a predator_—Ès fierce intensity into its small body. It_—Ès one of the most colorful of all raptors; the male_—Ès slate blue head contrasts elegantly with a rusty-red back and tail. Hunting for insects, small rodents, and birds in open territory, kestrels perch on wires or poles, or hover facing into the wind, flapping and adjusting their long tails to stay in place. Kestrels are declining in parts of their range, but you can help them by putting up nest boxes. The Cornell Lab of Ornithology has developed QR codes which allow you to listen to the songs and calls of hundreds of birds, right from your smart phone. We have harnessed this educational technology to allow you to hear these birds sing while completing your puzzle. The QR code is on the back of the box.