Let’s talk about butterflies!
This spring, our pollinator bed was full of dill! Dill is a delicious herb that is commonly used for pickling cucumbers (dill pickles, anyone?). This herb also serves as a host plant for the Black Swallowtail Butterfly. Because we had so much dill, the Black Swallowtail Butterfly paid our garden a visit.
As I was harvesting milkweed and dill seeds, I noticed four caterpillars feasting on our herbs. In a perfect world, I would have left the caterpillars to survive on their own. But the truth is, these caterpillars will devour all the dill growing in our garden, leaving none for donation. We also have a very active predatory population of spiders, birds and parasitic wasps that enjoy hunting caterpillars.
So what did our office do? We took them in, of course!
Caring for caterpillars is relatively easy; all you need is space and plenty of food.
We placed each caterpillar in its own ventilated container with sufficient food. The swallowtail caterpillar primarily consumes dill, parsley and fennel. Fortunately enough, I had some parsley leftover from the Farm to Work program our office is currently leading.
It was incredibly important to keep the caterpillars fed. If they ran out of food, they would enter the chrysalis stage too early and would not survive as butterflies.
Soon after bringing in the caterpillars into our office, they entered the pre-pupal stage – you can see the caterpillar hanging from the dill stalk getting ready to form a chrysalis!
It only took a few hours for the caterpillars to form a bright green pupa; they all stayed in this stage for approximately one week. The chrysalis hardened and darkened, allowing for some of the distinctive yellow spots to be visible through the exoskeleton.
After many days of anticipation, our first butterfly emerged! We were able to transport him to our garden so he could get all the nectar he needed. Recently enclosed butterflies require some preparation before flying. They hang upside down to allow fluid to pump into their wings, enlarging them in the process.
Soon enough, our butterfly was ready to fly!
Seeing this process unfold allowed everyone in our office to appreciate how difficult it is for our pollinators to survive. From the very beginning, the caterpillar could have been consumed by a bird. If it made it past the larval stage, it could have been infected by a parasitic wasp, ending its already short lifespan. This doesn’t include the damaging effects glyphosate, a broad-spectrum herbicie, has on butterfly populations.
Raising these caterpillars and watching them become butterflies was an amazing experience, and it allowed us to learn a little more about one of our favorite pollinators. With all this experience, we may continue rescuing caterpillars.
Next project: Raising Monarchs!