Birds are flying vertebrates. They are built to fly with feathers and a strong but lightweight skeleton. All birds have beaks, and their beak shapes are specialized to the food they eat. For example, predatory birds (raptors) like hawks have hooked beaks to kill and dismember prey. Hummingbirds and other nectar feeders have bills designed to fit into flowers. Although bird songs can sound melodic and simple, they are very specific calls used to attract a mate or warn other birds.
Arizona is a bird-watcher’s paradise. Saguaro National Park contains many species that can be seen few other places in the United States, such as vermilion flycatchers and whiskered screech owls. The diversity of habitats in the park ranges from lowland desert up to pine forests. These diverse ecosystems support a surprising array of bird life. Common desert birds include greater roadrunners, Gila woodpeckers, and Gambel’s quail. Northern goshawks, yellow-eyed juncos, and Mexican jays can be found in the park's higher elevations.