Critically endangered butterfly appears right on cue

Posted on 24 January, 2023 by Ivan

Our recent Eltham Copper Butterfly workshop received a surprise visit from three flirty Eltham Copper Butterflies, with the enthusiastic crowd delighted to see the special butterfly ‘in-person’ at the Castlemaine Botanical Gardens (Castlemaine VIC) on Saturday 14 January 2023. It was the first occasion most participants had seen an actual real-life Eltham Copper Butterfly, and was a tribute to the advocacy and management practices progressed by local ecologists to protect this iconic species.

The education workshop was delivered by the wonderful and passionate Elaine Bayes from the Wetland Revival Trust, and included a guided walk exploring the native woodland north of the botanicial gardens. Elaine delivered an informative and engaging presentation on the fascinating biology of the threatened Eltham Copper Butterfly and its symbiotic relationship with Notoncus ant species. It was warming to hear Elaine’s enthusiasm about the mating cycles of this butterfly and her excitement that more populations may exist around our region, and could be discovered if we continue monitoring.

It was a very hot day, and Elaine warned us we were unlikely to see any butterflies on our short walk. However, within minutes of us entering their habitat, three Eltham Copper Butterflies miraculously appeared! They appeared unfazed by our presence, providing excellent photo opportunities.

Event participants engaging and photographing the rare sighting (photo by Ivan Carter)

The Eltham Copper Butterfly (Paralucia pyrodiscus lucida) is only found in Victoria, Australia and is restricted to only a handful of locations. Until recently it was only found at several sites around Castlemaine, Bendigo, Kiata (near Nhill) and Eltham. It is a small and attractive butterfly with bright copper colouring on the tops of its wings visible during the summer flight season.

It is one of the rare good news stories within the extinction crisis in Australia. The Eltham Copper Butterfly was considered extinct in the 1950s until rediscovered at Eltham in 1986. This butterfly has a fascinating ecological relationship with Sweet Bursaria plants and Notoncus ants, and lives in bushland at several locations around the township of Castlemaine.

Historically, survey efforts and management actions have focused on public land. However, we know there is potential Eltham Copper Butterfly habitat on adjoining private land around Castlemaine. This habitat is under threat from urbanisation, weeds, rabbits, changed fire regimes and grazing. Connecting Country is currently working with local landholders around local butterfly populations to help protect remnant vegetation, control weeds and rabbits, and revegetate with Sweet Bursaria and other plants used by the butterfly.

Some interesting Eltham Copper Butterfly facts:

This unusual species due has a close symbiotic association with a group of ants from the genus Notoncus and the shrub Sweet Bursaria (Bursaria spinosa).
Adult butterflies lay their eggs on the roots and stems of Sweet Bursaria. Once the eggs hatch, the ants guard the caterpillars (providing protection from predators), ushering the larvae to and from the ant nest at the base of the shrub, to feed on the Sweet Bursaria leaves at night. In return, the ants feed on the sugar secretions exuded from the body of the caterpillar.
The butterfly prefers open flight paths and receiving direct sunlight. It likes vegetation with an open middle and understorey.

The workshop was funded by the Australian Department of Industry, Science and Resources as part of the Environment Restoration Fund and Threatened Species Strategy Action Plan.

It was exciting to have the opportunity to learn about the latest monitoring results from Elaine and see some Eltham Copper Butterflies in the field. We have received some terrific photos of the exciting sightings from Jo Douglas and Malcolm Mars, which we have included below. Thank you Jo and Malcolm, and well done to everyone who attended.