Butterflies and caterpillars
29th October 2023
By Arimbi Winoto
“When we try to pick out anything by itself, we find it is hitched to everything else in the universe.”
John Muir (1911, American explorer, naturalist and conservationist)
October – it’s warming up with the odd wild storm thrown in, including wind, rain, hail and thunder today after having been 29 degrees just a week ago! It will be November by the time you read this. Sprummer according to ex-director of the Royal Botanic Gardens, Tim Entwistle. Of course, much earlier than this term was the Wurrundjeri peoples’ more nuanced Poorneet - Tadpole Season (September-October) and Buath Gurru - Grass Flowering Season (November).
The wattles have just about finished flowering and other plants are sprouting. The first early nesting birds have fledged. While some are on their second nest families, others are still sitting on their first eggs, or feeding new nestlings. Insects, including the first early butterflies, are starting to be seen. Of course, we wouldn’t have butterflies without their grubs or caterpillars, and they’re a nice illustration of our complex web of life.
You can find a comprehensive list of some 24 butterflies and moths occurring on Merri Creek (on the iNaturalist app > Papillionae > Locality – Merri Creek Bioblitz), but I have picked out just a couple of the more common. Some are migrants from the north. Caterpillars feed on host plants while butterflies feed on nectar, some butterflies lay their eggs singly and some lay egg clusters. There is an amazing variety within the specifics of their life cycles. In further and intersecting cycles of life they are part of the food chain and predated on by birds, lizards, frogs and beetles. When not feeding, caterpillars tend to hide in grasses or at the base of their food plant.
Green grass dart butterfly, Ocybadistes walkeri, Arimbi Winoto
The Green Grass Dart (Ocybadistes walkeri) is an orange skipper type butterfly, with knobbed antennae. They attach a single white egg to blades of grass, from which a brown-headed green caterpillar emerges to feed on Dianella and various native and introduced grasses. It rests by day in a grass shelter.
The common Pea Blue butterfly (Lampides boeticus) is about 25-27 mm and has “slug-like” caterpillars which feed on the flowers and immature pods of plants in the Fabaceae, or pea family. They are not fussed whether the peas are native or introduced, so you may find them on your sweet peas, or beans, or you may like to plant scarlet runner (Kennedia prostata with bright red flowers) or Pultanea sp with yellow “egg and bacon” type flowers.
Another common small blue butterfly is the Saltbush Blue (Theclinesthes serpentata). As its name suggests, the caterpillar feeds on the many different saltbushes growing along Merri Creek.
The Meadow Argus (Junonia villida) is a cheery brown and black butterfly, with blue circled by orange eyespots on the wings. You may see them sunning themselves on the ground, with their wings open. The 4 cm brown spikey/hairy caterpillar feeds on a variety of plants, including fanflowers (Scaevola sp.), convolvulus, sweet scabiosa and verbena.
Have fun finding these insects or their caterpillars, along Merri Creek or planting to entice them into your garden or balcony – there are loads of resources, of course, and I list a couple here.
Gardens for Wildlife – Factsheet – Butterfly attracting plants
iNaturalist
Butterfly Conservation SA Inc.
Melbourne Museum
Lepidoptera.butterflyhouse.com.au
Image: Saltbush Blue, Jonathan Tickner, CC BY-NC 4.0 DEED