This adventure all started when a friend of mine saw a tiger swallowtail lay its eggs on a willow leaf, and he took me out there to show me. We started looking around the foliage to see if we could find a caterpillar, and he spotted this one nearby.
It grows up to 2 inches. It can be deep to light green. It has yellow eyespots with black and blue pupils. It is swollen in the front which accentuates its eyespots.
It wove a small silken mat that appears to act as a home. It rests there most of the time, remaining motionless to avoid detection by predators. When I went to check on it the other day, it left the mat to eat part of a leaf nearby and then promptly returned to its spot.
It has a large variety of host plants including cottonwoods, poplars, ashes, aspens, alders and willows.
I took a photo of the eggs, and when I went to check on them yesterday, I saw that they had hatched. They start off as these small, black caterpillars with a white band in the middle.
I am hoping to have the opportunity to see the creation of the next stage of its life cycle — the chrysalis. It is dark brown and wood-like and is attached to a twig or the trunk of a tree. It overwinters, and the butterfly emerges the following year completing the life cycle.
In a word, the metamorphosis of an egg to a butterfly is miraculous.
