This female is about the size of a small bird. She fluttered around for a long time, keeping between one and three metres off the ground, pausing briefly to check out the plants for suitable ovipositing sites. Nothing seemed to take her fancy.
I mistook her at first for the more widespread Orchard Swallowtail (P. aegeus), beautiful bane of citrus growers along the east coast. But female P. aegeus have blue spots on both the upper and low surfaces of the hind wings. These are absent in P. ambrax. The Ambrax Swallowtail is also tied strongly to rainforest, whereas the Orchard Swallowtail is more catholic in its habitat. It has almost certainly extended its range thanks to the (inadvertent) kindness of gardeners.
