New surveys for Eltham Copper Butterfly habitat in Chewton
Posted on 22 April, 2021 by Ivan
The Eltham Copper Butterfly (ECB) is one of our most interesting and treasured local threatened species. We are fortunate to have the largest population in the world right here in the Mount Alexander region of central Victoria. In the past few years, this special little butterfly has attracted some much-needed attention, with several small but important projects active in our region.
Passionate local butterfly gurus, Elaine Bayes and Karl Just, have obtained new funding to assess additional local sites for habitat suitable for Eltham Copper Butterfly during 2021-22. This includes the bushland around Castlemaine and Chewton.
The initial surveys will involve habitat assessment of the Chewton Bushlands for Sweet Bursaria (Bursaria spinosa), a plant vital to the Eltham Copper Butterfly’s life cycle. A team of volunteers will map the density of this beautiful flowering shrub. These maps will be used to plan surveys for the butterflies when they become active, in the warmer days of early summer days. The relationship between the density of Sweet Bursaria, and the presence of the Eltham Copper Butterfly has been identified in previous surveys in 2019 and 2020, around Kalimna Park in Castlemaine.
Stay tuned for further information about the Sweet Bursaria and Eltham Copper Butterfly surveys, which bring a real possibility of discovering new records for this threatened species. We acknowledge the commitment of the Eltham Copper Butterfly volunteers, and Elaine and Karl, who are committing much of their time to help protect and improve the habitat for this fascinating species.
In 2019-20, Connecting Country delivered a popular community education workshop, and worked with ecologists Elaine and Karl to promote and coordinate four community monitoring sessions for Eltham Copper Butterfly around Castlemaine, when the adult butterflies were out and about. These events attracted many people keen to learn more about the life cycle of this butterfly and to participate in butterfly monitoring within local butterfly habitat. The aim was to support interested community members to learn how to monitor with expert guidance, providing skills for them to become citizen scientists, conduct more monitoring and (potentially) discover new populations. For details – click here
Ecology and habitat
The Eltham Copper Butterfly is a small attractive butterfly with bright copper colouring on the tops of its wings. It is endemic to Victoria, where it mostly lives in dry open woodlands. The Castlemaine-Bendigo population covers the largest area (>100 ha but full extent unconfirmed), followed by Kiata (90 ha) and Eltham-Greensborough (8 ha). The Eltham Copper Butterfly is only ever found in areas where Notoncus ant colonies are present, confirming they have a truly symbiotic relationship.
Adult Eltham Copper Butterflies lay their eggs at the base of Sweet Bursaria plants. The larvae hatch and make their way to the ant nest, where the caterpillars are guarded by the ants, which lead them to and from the ant colony to browse on the Sweet Bursaria leaves. In return, the ants feed on sugar secretions which are exuded from the caterpillars’ bodies.
Larvae pupate in or near the ant nest, with adults emerging from October to March each year, peaking from November to January. The adults feed on nectar of Sweet Bursaria flowers, and flowers of other plants such as Hakea species.
To learn more about this fascinating little butterfly, including ecology, distribution and information on how to identify this species from similar look-alike butterflies – click here
Please enjoy the following video (courtesy of the N-danger-D Youtube Channel) that includes some excellent footage of this wonderful butterfly and symbiotic ant species.