A couple of years ago, I bought a Dutchman's Pipevine (Aristolochia californica) at Native Here Nursery, to plant in my woodland garden. My hope is that it would cover the fence during the winters (it's summer dormant in my garden) and attract California Pipevine Swallowtail Butterflies. So far, I haven't seen any action on the caterpillar front, though it's always nice to see the pipevine coming back after a chilly winter.
I know it doesn't look like much at the moment. This vine covers the riparian waterways of many counties in California, and is the only host plant for this particular swallowtail.
I first discovered Dutchman's pipevine on my walks with the preschool kids from Wellspring school, back when we held class in the Lafayette Christian Church on Glenside Drive. We'd take a daily walk on a bike path that used to be a railway. This path wends its' way next to a creek, which never completely dries up in summer, though it's just a trickle in the hottest months. In the winter it roars with water, and the kids liked to watch that, particularly from one bridge that passed over the creek. In spring, we would see dozens of Pipevine Swallowtails, and eventually I put two and two together and realized that they were laying eggs on the Dutchman's pipevine. And then, I started to notice bright green chrysalises attached underneath the top rail of the bridge fence. It all started to complete a picture of the life cycle of the swallowtail.
Dutchman's pipevine is a very interesting plant when it's in bloom, and quite pleasing even without the butterflies. Mine has never bloomed, so I will show you a picture from Calscape, a website I use quite a lot for gardening with California natives:
So the adult butterflies lay their eggs on this plant, but feed themselves from all sorts of nectar-rich flowers, just as other butterflies do. There is a lot of evidence that both the butterfly and the vine have declined greatly in the last few decades, so there is a project to try to bring them both back, and you can access that project here at iNaturalist. I've added my vine to the list of places it is growing, and hopefully eventually I can add that I've seen the swallowtail here as well.
Meanwhile, I decided to take one of the chrysalises from the bridge in Lafayette and bring it home to hatch. There were many', so I felt ok collecting one for me and one for a friend who also is participating in the Dutchman's pipevine project. I have hatched butterflies in the past but no longer have the net I used to use. So I had to buy a net, and it's made for kids, so it's a festive looking thing; I placed a cotton towel down at the bottom of the net and put the chrysalis there to rest. When the butterfly hatches, it will climb up the sides to dry its' wings.
You can see that it's brown now. From what I've read, this is normal. It seems that some of the chrysalises are green and some are brown. Honestly I think they turn darker just before they hatch, so I'm hoping this lady will hatch soon. These butterflies do often have a diapause phase, which means they may not hatch until much later, or even next year. So I may not see anything happen for a very long time. The net is on my front porch where it is protected from the weather, but still outdoors. I put a little water, just a tiny drop, on the pupa every day or so. It seems that the butterfly's emergence is not triggered by day length, but rather by the amount of water it's receiving (which seems smart in dry California), but this process is not well understood. It's exciting to think of the metamorphosis that is going on inside, regardless. In nature, the caterpillar forms the chrysalis and attaches it to the underside of something with webbing, like in the picture below. I guess that protects it a bit from the weather. Apparently you don't need to do this in a net. When it does hatch, I'll place it on the pipevine in my yard. I'm also hoping to scour the creeks near here to see if there is any growing naturally.
I enjoyed this article about the effort to bring large numbers of this butterfly back to the Bay Area (I also enjoyed the accompanying photos).
I hope to update you shortly with photos of the emerging butterfly. Meanwhile, have you done anything like this where you live? In future, I'm thinking it might be worthwhile to bring in some of the Anise Swallowtail caterpillars I see on our fennel every year, and let them pupate inside. Mostly they get eaten by the birds.