(Article and photos by Barbara Weller)
My daughter has a ‘Butterfly’ vine growing on the side fence of her house in Townsville. I am unsure whether it is an Aristolochia tagala or Pararistolochia deltantha but the Birdwing butterflies really like it. On my recent visit there were several larvae (caterpillars) living on the vine – they ranged in size from about half a centimeter to about six centimeters in length although they would be smaller when newly hatched.
From the description they appear to be Cairns Birdwing caterpillars with colourful spines to ward off predators. Unfortunately, as described in this on-line reference, the caterpillars do tend to ringbark the vine when almost ready to pupate. Although leaves droop from water loss, the flow of nutrients is concentrated so the caterpillar gets a more nutritious meal before pupation. Pupation occurs in a cleverly camouflaged cocoon, which resembles a dead, dried leaf. (http://beforeitsgone.com.au/2011/05/03/backyard-beauties-the-cairns-birdwing-butterfly/)
Two caterpillars had pupated but the butterflies had not hatched when I left for home. However, just before I came back to Toowoomba, I was fortunate to see a female birdwing, which is not as brightly coloured as the male, fluttering around the vine and probably laying her eggs on it. I was not quick enough to take a photo.I have planted two ‘Butterfly’ vines on my side fence in Toowoomba with the hope of attracting them to my garden and contributing to their long-term survival. However, these vines are different and designed to attract the Richmond Birdwing. So far, no luck!