Newley Emerged Pale Swallowtail Caterpillar

This post is a follow-up to two earlier posts I wrote titled “Pale Swallowtail Butterfly Eggs” and “Butterfly Egg Hatches“.

The life of a pale swallowtail caterpillar is not only rare to experience, but extremely slow and methodical compared to other caterpillars I’ve raised.

The tiny pale swallowtail caterpillar hatches from it’s egg in only 4 days, spending most of it’s first day eating it’s own egg shell before setting out to explore it’s new surroundings.

If you’ve read my previous posts, you know the egg was mistakenly laid on a common fruit bearing peach tree in my neighbors back yard (peach trees are not considered to be a host plant for the pale swallowtails, although peach trees are in the prunus family).

Pale Swallowtail Caterpillar 2nd instar

I had offered the newly hatched pale swallowtail caterpillar a smorgasbord of host plants to eat.  Finally settling on the coffeberry (Rhamnus californica), taking only a small bite on the edge of the leaf, then returning to the center of the leaf to rest for the remainder of the day.

After watching the pale swallowtail for a couple of weeks now, I’ve started to realize there is a mythological pattern in it’s behavior.  First of all, this is a very long time for a caterpillar to still be a caterpillar and the time it takes to molt (intsar) is much slower than other caterpillars I’ve raised. I have rarely seen my pale caterpillar move, let alone eat.  I check on it first thing in the morning, noticing that the coffeeberry has been munched upon and frass (caterpillar droppings) are in the bottom of the container, but the caterpillar is in the exact same position as the day before.  I’ve realized the actions of my pale swallowtail caterpillar are all done privately, in the middle of the night.

Pale Swallowtail Caterpillar 5th Instar

“The larger and more mobile a caterpillar becomes, the more visible and tempting it is to potential predators. Newly interested parties including birds, lizards and spiders are among the large list of dangers a caterpillar can face. Such luxuries as claws, beaks and venom are not at a caterpillar’s disposal. Nor can a caterpillar scamper, hop or fly away quickly from a perilous situation. Fortunately, however, over time these amazing creatures have adopted and learned to survive despite the incredible challenges they face each day.” Excerpt from Butterfly Dimension by Kristen D’Angelo.

Day after day, moving slowly, molting, pooping and eating only at night, he grows. My methodical pale swallowtail caterpillar is in it’s 5th instar, almost ready to pupate into a chrysalis.  I’ll keep you posted.  ~ Vickie

Pale Swallowtail Butterfly Egg

One of the 3 Pale Swallowtail eggs has darkened up and looks like it’s getting ready to hatch.  The other two eggs are still clear, I suspect they are duds, but  I will know for sure in a couple days.

The darkened egg hatches and out crawls. . .a tiny pale swallowtail caterpillar.  First thing he does is eat his entire egg.  I’ve set him up at a “makeshift salad bar” complete with the most tender green leaves of coffeberry, cherry,  California lilac and, and of course the leaf that he was laid on, peach (which is NOT considered a host plant for the pale swallowtail) .