If you want to find the bird, you should rely on your ears as well as your eyes. According to master birder Roger Tory Peterson, the scarlet tanager's singing is like that of a robin "with a sore throat." May is the best month to spot the scarlet tanager — as spring gives way to summer, the males' bright red plumage turns to a yellowish-green. Scarlet tanagers are most common in the eastern half of the U.S. from southeastern Oklahoma to northern Alabama and from northern Georgia to just above the U.S.-Canadian border. Related species are not quite as bright but are beautiful in their own right. The male Western tanager, common to the western states, has a red face and a yellow body with black back, wings and tail. The male summer tanager of the southeastern U.S. is red all over.