Earlier this month, Kate spotted some wild fennel stuffed into a yard-waste bin here in the neighborhood. Wild fennel, which has become profuse here, is kind of weedy and annoying; once it takes root, it’s very hard to get rid of.
But it’s also a host plant for a butterfly called the anise swallowtail (Papilio zelicaon), whose image has graced this blog before. It’s a largish black-and-yellow beauty, at least in the eye of this beholder.
So, having spotted the fennel in the bin, Kate took a look to see if any anise swallowtail caterpillars might be there, too. To her surprise, she found 10, including a couple that were probably close to going into their chrysalides. So she brought the caterpillar and their host sprigs of fennel back home, where they took up residence in our dining room.
Within just a few days, one of the caterpillars crawled onto the vase that held the fennel and began preparing to go into its chrysalis. We left town for a couple of days, and when we came back, the chrysalis was complete. (See the photos below; click for bigger versions of the images.) That was less than two weeks ago. Since we’ve sometimes watched chrysalides for months and months before a butterfly appears (if one appears at all), I was kind of thinking we’d be into the autumn before anything more happened.
But this morning, Kate got up, walked into the dining room, then called out, “We have a butterfly out here now!”
So now, it’s doing what it needs to do for the next stage in its life cycle. We’ll watch.
One of Kate’s sideline projects the past couple of years–part of her elementary school science teaching–has been to raise anise swallowtail caterpillars to the point where they go into the chrysalis, then harbor the chrysalides until the butterflies emerge. It’s not easy. We had a couple of chrysalides on the back porch that some predator–a bird, probably–came and picked off. After that, Kate improvised some netting to protect the five remaining caterpillars, which in due course changed to chrysalis form.
The last of them changed probably a month ago, and what we’ve had, first on the sometimes very warm back porch and then in a shadier spot in a side yard, is a green plastic box with some sticks in it that have had some dead-looking mummy-type things hanging from them. Honestly–when you look at these objects, it’s a little hard to believe anything living can emerge from them. But we’ve been checking every morning anyway.
Yesterday, a surprise: a newly metamorphosed anise swallowtail butterfly, perched on one of the net-supporting hoops in the green box. We were headed out for the afternoon, but we lifted the netting to give it a chance to fly away when it was ready. When we got home, well after dark, it was gone. I’d like to think it got a chance to feed and perhaps eluded for a few hours anyway whatever out there in the world will look at it and see food. I’d like to think that it might find a like-minded anise swallowtail of the opposite sex and get a shot at perpetuating their kind.
Last year, Kate started using anise swallowtail butterflies as part of the biology unit in her second-grade class. As the name might suggest, the anise swallowtail (Papilio zelicaon) are partial to anise (fennel) plants and their relatives; in some areas, the go for citrus, too. Our neighbor has a healthy stand of fennel in one corner of his yard, and the last two springs the plants have hosted anise swallowtail eggs and larvae (caterpillars). The one pictured here is apparently in its fifth and final “instar” (larval stage) before becoming a pupa (or, as I’ve always thought of it, “going into its chrysalis”). It’s an amazing little street-side biology lab we have here. (Oh, yeah: And you get a dollar if you can tell me what that little brown spheroid at the caterpillar’s posterior end is.)
A late spring project for the teacher in the house: Raising some anise swallowtail caterpillars/butterflies. We’ve got three in a nice little plastic crate habitat on the dining room table. The two visible here (on some fennel, one of the species’ preferred foods) are both in their chrysalises now; a third one that didn’t look like it was going to make it developed later and looks like it will go into its chrysalis soon. Two things about these bugs: One, despite growing up with the “knowledge” that moths come from cocoons and butterflies from chrysalises, I’ve never seen the process in action before (Elle, a friend of Thom’s, brought over a bunch of fennel that had caterpillar eggs on the branches). Two, though I’ve seen this creature in both caterpillar and butterfly form, I never had any idea that they were associated (mostly) with the fennel that grows everywhere here.