The adults will nectar from a variety of different flowers including the flowers of the milkweed plant.
The genus Danaus is from Greek mythology. Danaus was the king of Argos and the father of the Danaides. The origin of the specie gilippus is currently unknown.
The Queen butterfly prefers areas which are very open and arid that are in close proximity with their host plants such as a prairie.
To find a mate, the males patrol the habitat releasing pheromones to attract the attention of a female. After mating, the female lays her eggs in a variety of locations on the host plant. When the eggs hatch the caterpillars feed on the host plant until they form their chrysalis.
In the warmest part of their flight range, there are multiple generations which make it possible to find adults all year round. In the northernmost part of their range there are still multiple generations, but they are found April-October.
Milkweed plants contain cardiac glycosides and when the Queen caterpillars feed on those plants that compound is dispersed throughout their body. The compound not only makes the caterpillar taste bad, but it carries over to the adult stage making it unappetizing to predators as well.