Beautiful black and white butterflies

Around October, the Caper White butterflies arrive on Raakajlim in the northern Mallee. There's a pale form and a dark form of the butterfly. This had me confused for a long time!

The butterflies blow in on the northerly winds and flap about but they don't generally breed here. Their food plants are further north in NSW and Queensland, in the caper family (Wild Orange, Currant Bush, Native Caper). But I've just planted some Caper plants in my garden so it will be interesting to see if caterpillars completely defoliate the plants!

I'm looking forward to seeing a mass migration. In 2016, there was a huge migration with clouds of butterflies flying at 2-3m above ground. Sadly though, the migrations aren't always well thought out and have ended up in the sea, or at a location with no host plants to feed the caterpillars.

Chequered Swallowtail doing its thing ...

The food plant for the caterpillars (Cullen) is growing in abundance this year, so I guess the butterflies are too.