The long tradition of vampire myths can be scary to a lot of people. But for birds that evolved on the harsh Galapagos Islands, drinking blood is necessary. That doesn't make vampire finches and hood mockingbirds any less creepy! Readers learn about the healthy treat blood can be for some kinds of birds as well as how they came to use it as a source of nutrition. Full-color photographs introduce these bloodthirsty birds, and fact boxes provide additional science information to enhance the main content.