Caterpillar season

Our Wet season is the ideal time for caterpillars since that is when their food plants are growing best, so it makes sense that the Wet is also peak butterfly mating and egg-laying time. In the last week or so I have seen lots of Migrants, Eggflies and Crows and observed both mating and egg-laying; I have also seen a few Hawk-moths and know they have been similarly busy. Here are two caterpillar stories from the last few days.

The Common Crow

orange caterpillar with black and white stripes
The very colourful caterpillar of the Common Crow, Euploea core, on a Desert Rose

Don Herbison-Evans says this caterpillar is usually found on Oleander but is also known to feed on Frangipani. The Desert Rose, Adenium obesum, is a member of the family Apocynaceae, as are both of these, so the Desert Rose is a logical addition to the list. The adult butterfly is a rather plain black and white creature, as the name suggests:

Common Crow 7733
Common Crow, Euploea core, on snakeweed (an exotic pest species, but the butterflies love it) on Cape Pallarenda.

I saw one of them alight on the Desert Rose, curl its abdomen around and lay an egg … then went and got my camera:

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Egg of Common Crow on Desert Rose

The egg is about 1.5 x 1 mm and a close-up of it is here. What will happen to it when the flower opens, I wonder?

The Hawk-moth

green caterpillar
Young Hawk-moth caterpillar on what’s left of a pentas leaf, one of their favourite foods – in our garden, at least

Hawk-moths are quite large and heavily built and so are their caterpillars but this is a very young one, about as thick as a toothpick and two-thirds as long. The tail-spine and the eye-spots are characteristic. A gallery of older individuals, both caterpillars and adult moths, may be seen here.

 

Cairns Birdwing, laying eggs

A tangled mess of creepers sprawls untidily near our front gate, supported by the tall stump of a grevillea and a couple of nearly-dead frangipanis. It is really not very attractive but we leave it alone for the Aristolochia vine which threads through the Golden Orchids, Gloriosa and other creepers.

What’s so important about Aristolochia? Simply that the caterpillars of the spectacular Cairns Birdwing, Ornithoptera priamus euphorion, will eat nothing else, so a vine guarantees frequent visits from Australia’s largest butterfly. A couple of days ago I saw the first female of the season laying her eggs on it:

Cairns Birdwing butterfly, Ornithoptera priamus euphorion, laying an egg on Aristolochia vine
Cairns Birdwing butterfly laying an egg on Aristolochia vine. (Its leaves are seen most clearly on the left of the photo.)

These very large butterflies hover to feed and they hover – very briefly – to lay eggs too: one dab under a leaf and off she will go again. She will repeat the process dozens of times in a single session, then fly off to rest, feed and perhaps mate again.

The eggs hatch into dark spiny caterpillars which turn greyish as they grow to finger-size, then pupate in leaf-like cocoons before emerging, months later, as adults. Clicking here will take you to a collection of my older photos showing males, females, caterpillars and cocoons.

A word of warning from the Wet Tropics Management Authority: Growing the native rainforest vine Dutchman’s Pipe (Aristolochia tagala) will encourage regular visits by this impressive butterfly. However, beware of the exotic Dutchman’s Pipe (Aristolochia elegans) which is poisonous to the Cairns Birdwing caterpillars.