Cairns Birdwing butterflies emerging

black and green butterfllies
A female Cairns Birdwing (top) has just emerged from the chrysalis at lower right, and the older male has mated her immediately

Three weeks ago I wrote about the collection of Cairns Birdwing chrysalises we found on our bottlebrush tree and observed that we should be seeing the adults emerging “around the end of the month.” They have been appearing for a few days now, so it seems that some of the chrysalises were a bit older than we thought.

black and green butterflies
The same mating pair, fluttering up the tree

Normal courtship involves the hopeful male flying close below and behind the larger, darker female as seen here and doing aerobatic tricks around her; if she is impressed enough, she will allow mating to begin.

However, males have no compunction whatever about taking advantage of a female who is still waiting for her wings to stretch and dry after squeezing out of her chrysalis, and that is what has happened in the photo above.

(How do I know the male is older? Simple: when you look closely, you will see that his wings are quite battered.)

As her strength increased, she fluttered and crawled higher in the foliage, dragging him with her.

black and green butterflies
The same couple at a better resting point

This happened late yesterday afternoon and was the second emergence we saw during the day. Meanwhile, we still have half-grown caterpillars in the garden, and others full-grown and beginning pupation.

I checked on the seasonality of the species and Braby’s huge, authoritative Butterflies of Australia said that adults appear all year round but chrysalises can lie dormant for some months in the dry season. That makes sense, since there is no point emerging as an adult when the caterpillars’ food plants are not growing well.

Don Herbison-Evans’ page about the species lists their food plants and provides links to information about them.

black caterpillars
Caterpillars eating the bark of an Aristolochia vine on the trunk of a bottlebrush tree

Our caterpillars have been eating the bark of the main stems of our largest surviving vine andĀ (once again) we would love to hear from people who have moreĀ Aristolochia. I’m sure that if we gave away all the caterpillars we could find we would still have more than we can feed.

3 thoughts on “Cairns Birdwing butterflies emerging”

  1. Hi, I just saw this today.. . I have got lots of tagala vine at Butterfly Heights so if you have more caterpillars at any stage I would love to adopt some!!! Thanks for a great article too.

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