The Prime Directive and the Owlet Looper Caterpillar Dilemma
Updated: Dec 25, 2021
OR Coexisting with nature is as complex as trying to follow Star Trek’s Prime Directive.
In anticipation of the first hard freeze back at the beginning of last December I cut a bouquet of flowering basil to extend my fresh basil harvest. The cuttings rooted easily in water, so the leaves were still fresh a few weeks later. I started noticing what looked like caterpillar droppings on the windowsill. Not sure if it's pandemic related, but figuring out what to do with a caterpillar in January was too much to process and I deluded myself that they were large basil seeds even though I knew this was impossible.
When it became clear the leaves were being stripped, I looked closer and found a camouflaged green owlet looper caterpillar.
I let him go through enough instars to become a big, fat squishy caterpillar.
One day instead of my new friend I found a cocoon on a leaf. This is the shoulda, woulda, coulda dilemma I didn’t want to deal with in the first place! Maybe I should have put him outside when he was a caterpillar? Could he overwinter in my windowsill? Should I put the cocoon on my platform birdfeeder for hungry winter birds? Would birds even eat a cocoon if I put it out for them? Could this cocoon even become a moth? Maybe I should just put the cocoon under a pile of leaves outside and hope for the best?
My background is not science, and rewilding my yard is a passionate, mission driven hobby, not a job. I didn’t know the answer to any of these questions. Maybe after sheltering in place for almost a year my world was becoming just a little too small because I was seriously upset about what to do. None of information on the internet about the owlet looper moth lifecycle explained the most eco-friendly thing to do if you find one in your kitchen on a bunch of basil in January. Naturescaping to attract moths is apparently not as common as ridding your garden of moth "pests". When I told my husband about my existential struggle over the cocoon situation, he said it sounded like a classic Star Trek Prime Directive problem. The crew was prohibited from interfering with alien life forms in the worlds they explored. Nice nerd reference from my brilliant husband. I like the idea that I’m not merely rewilding my yard, but basically exploring another planet! I have little idea how everything in a yard ecosystem interacts, and ideally the best I can do when I encounter wildlife is interfere as little as possible. Even well-intentioned actions can harm wildlife such as putting up poorly constructed bee houses that attract bee larvae killing parasites, having dirty bird feeders that spread disease, or letting hummingbird feeders become deadly if they become moldy.
In this case I’d already broken the Prime Directive because the caterpillar was on a leaf I brought in from outside. The basil leaf would have frozen and withered that night if I hadn’t brought it inside. The caterpillar would have been dead…I think. One reason we want caterpillars in our yard is because they are one of the top contributors in the food web . They turn plant matter into life sustaining protein for birds. I just didn’t have the heart see if birds would eat the cocoon, so I just let it be on my windowsill for a few weeks. At that point I wasn't sure if there was a pupa still inside the cocoon or if he was alive. The silky cocoon was still green and not decomposing though, so maybe he thought he was overwintering in plant debris like he would do outside?
A whiff of Spring was in the air in Atlanta and keeping the pupa inside any longer didn't seem the right thing to do just so I could see an owlet looper moth eclose, I decided to follow the Prime Directive as best I could and put the cocoon under a pile of nice, warm leaves.