I wrote a few days ago about the butterfly “that got away” – after seeing what I thought was the largest Tiger Swallowtail I’d ever seen in the garden. Now I’m pretty sure that I was mistaken. It wasn’t a Tiger Swallowtail at all!
The Giant Swallowtail is cousin to the commonly seen Eastern Black and Tiger Swallowtail butterflies. It is also the largest species of butterfly in North America. Adult wingspan ranges from four inches to nearly six and a half inches across, with an average of about five and a half inches. Like its cousins, the Giant is brightly colored and has a whimsical hop to its flight. They are quite a fascinating species to watch as they move through the garden!
At first glance, I thought the Giant was a Tiger Swallowtail because of the main colors displayed. There is a big difference, though. The Giant is mostly black with a solid yellow band running diagonally from the tip of the fore wing across the thorax and across again to the tip of the other fore wing. In addition, there is another solid yellow band that runs from the middle of the tip of the fore wing perpendicularly across the fore wing band and then down diagonally along the border of the hind wings. The Giant’s tail is solid black, with a yellow “eye” in the middle. In contrast, the Tiger Swallowtail is mostly yellow with black stripes running perpendicularly across the fore wings, resembling tiger stripes. The hind wings on the Giant are also much larger than the Tiger.
As far as range of flight, Giant Swallowtails are very common throughout the deep south and southwest. Their range continues up from New Mexico, east of the Rockies through the midwest states. They are also common throughout Florida and along the eastern coastal states all the way up to Vermont. In northern climates, their flight is from May through August, and here in Central Texas, they can be seen into the middle of October.
Female Giants lay their eggs one at a time on twigs and leaves of their host plants, which include those of the citrus family, rue, prickly ash and hop tree. This is why Giant Swallowtail butterflies are also known as “orange dogs” and “orange puppies” because, in its larva form, it can be destructive to plants of the citrus family (1). As caterpillars, the Giant starts out looking like bird droppings, then develops into a brown snake-like worm with a false head and eye. If these defenses fail, like other swallowtail, they possess osmeterium, which poke out like orange antenna and emit a foul odor.
Adult Giants nectar on flowers of the milkweed family, japanese honeysuckle, goldenrod, lantana, bougainvillea and azaleas (2).
Did you know??
There are over 500 species of swallowtail butterflies in the world?
It takes about a month for a swallowtail butterfly to complete it’s journey from an egg to an adult. They move through four phases of development: egg, larva (caterpillar), pupa and butterfly.