When I walked into the family room this morning, I caught a whiff of dill and I remembered. Two days ago, I brought in the largest and darkest Black Swallowtail caterpillar from the garden, supplied it with fresh dill and parsley (in case it was still hungry) and secured it in the punch bowl where several Monarch butterflies have been born.
Yesterday, I saw the caterpillar had suspended itself by silk threads and was hanging upside down from one of the dill stems. That's just how they do it and just what I'd expected to find in the next couple of days. This is the equivalent of a Monarch assuming the 'J' position. Soon, it would shed its final skin and pupate.
When a Swallowtail caterpillar pupates at this time of year, it's anyone's guess whether there will be a butterfly emerging in about 9-11 days or whether this one is bundled up for the winter. There's still a lot of warm weather left, with enough time for a new butterfly to mate, lay eggs and do this all over again, so hopefully, I'll get to see a butterfly emerge.
The smell of dill reminded me to check on the little guy this morning and when I did, I found that I'd missed the actual forming of the chrysalis, that it had happened some time in the night. If I'd been more alert, I'd have sat watch so I could see it happen.
In the picture, you can see several things:
- The frass at the bottom of the bowl. That's caterpillar poop, in case you didn't know. The caterpillar rids its body of all waste just before it pupates.
- Its old skin, which it shed as it formed the chrysalis, is hanging on the dill stem, too. In previous moltings, the caterpillar would have eaten it.
- The color of the chrysalis. Swallowtail caterpillars can have chrysalides of varying colors. The most common is dark brown, but more rarely they will be light brown or green. Looks like we've got a green one, unless its color changes as the day goes on.