The Cloudless Sulfur is a common butterfly that can be found throughout the southern half of the United States down as far south as Argentina, but can be found in the West Indies and may reach as far north as southern Ontario. While a permanent resident in the tropical regions, Cloudless Sulfurs do migrate during autumn and spring, going south and north respectively. Unlike Monarchs, Cloudless Sulfurs fly at lower altitudes while migrating. This makes migration easier to observe, especially in autumn when numbers are generally higher, but also make them more vulnerable and likely to be killed crossing roadways. The adults prefer to feed on tubular flowers such as bougainvilla, cardinal flower, hibiscus, lantana, and morning glory, but the host plant for the caterpillars are the Cassia species in the pea family. Cloudless Sulfurs breed in disturbed open areas and many can sometimes be seen drinking from mud puddles.