Pipevine Swallowtail Caterpillar

It's that time of year again. There is a pipevine (Aristolochia californica) cascading over a tall wooden fence in the next block, and I always check for caterpillars when I pass by. Today I got lucky--there were three of them munching up and down the greenery.
This planting is part of the Butterfly Project, a local effort to reintroduce Dutchman's Pipevine to the area in order to provide habitat for this creature.

It was unseasonably warm here today--good for the tomatoes.