The Pieridae family of butterflies is characterized by white, yellow or orange wings often with some small amount of black or red. There are about 1100 varieties worldwide with around 58 occurring in North America. These butterflies can reflect and see ultraviolet light patterns which they use in courtship. Whites and Sulphurs are strong and steady fliers. Sulphur butterflies will sit in the sun with their wings closed and whites bask in sunlight with their wings sometimes partly open.