Eltham Copper Butterfly update: 2019-20 surveys

Posted on 3 December, 2020 by Frances

The Eltham Copper Butterfly is one of our most treasured and interesting threatened species, and we are fortunate enough to have the largest population in the world right here in the Mount Alexander region of central Victoria. This special little butterfly has recently recieved some much-needed attention, attracting funding for three separate projects in our region.

During 2019, Connecting Country obtained funding from the Mount Alexander Shire Council to increase community awareness and education regarding the butterfly, and to support citizen science monitoring in key locations to learn more about the local populations. We worked closely with local ecologists Elaine Bayes and Karl Just who, with support from Wettenhall Environment Trust, continued their vital work on mapping local Eltham Copper Butterfly habitat and distribution. We also joined in the excellent Butterfly Celebration Day held in Castlemaine Botanical Gardens in November 2019.

A citizen science event in 2019 attracted a strong crowd and interest in the Eltham Copper Butterfly (photo: Frances Howe)

The Eltham Copper Butterfly is a small and attractive butterfly with bright copper coloring on the tops of its wings visible during the summer flight season (photo: Elaine Bayes)

We have recently received an update from our expert Eltham Copper Butterfly (ECB) enthusisast, Elaine Bayes, regarding the 2020-21 ECB monitoring program. We admire Elaine, and her colleague Karl Just, for their extensive work on this threatened species. Without such dedicated individuals in our community, this special little butterfly might be more trouble that it already is.

Please enjoy the following update by Elaine Bayes

Due to Coronavirus we are not running any group ECB monitoring this season, however we would really appreciate it if anyone wants to get out and carry on searching for ECB habitat and/or ECB flying.

Priorities this year are:

Continue to search for ECB in the red and pink sections of Kalimna Park using the map we collated last year – see attached geo-referenced kalimna map with grids and yellow dots for last years ECB records and blue dots for past records) and ADULT method sheets.
And/OR replicate overall method we did at kalimna park re mapping ECB HABITAT at the 2 other ECB populations in Campbells Creek and Chewton – see dingo park map which has both sites on it and ECB habitat method.

Contact me if you have any questions or need me to explain the methods better.

Below is an update on the amazing success we had with this methodology last year at Kalimna and how it protected ECB from the planned burns that occurred there last autumn.

Eltham Copper Butterfly update from 2019 to 2020 surveys – Elaine Bayes

Last summer we were very lucky to receive support to carry out Eltham Copper Butterfly (ECB) surveys in Kalimna Park as well as many educational initiatives to promote this species locally.

During the October 2019 – January 2020 ECB flying period, the ECB at Kalimna park were surveyed by ecologists Elaine Bayes and Karl Just as part of a flora and fauna assessment for the Dja Dja Wurrung. In addition to this work the ECB Monitoring Group which now has 45 members, carried out additional surveys searching for ECB throughout this period. Collectively Karl, the group and I found: 113 flying adults, located 5 new ECB sub-populations and extended the area of known ECB occupancy from 3 ha (based on past data from 2005-2015) to 8 ha in 2019-2020 (this area is a polygon around ECB seen during this period, with 10m buffer).

In order to ensure that our efforts were focussed we only searched areas that supported the Sweet Bursaria host plant. To do this we developed a 50m grid across the park and carried out a rapid assessment of numbers of Bursaria plants within each grid and colour coded them (time spent was 48 hours). Overall, we assessed all 225 ha of Kalimna Park of which 73.25 ha was ranked prime potential ECB habitat. Using this map we focussed our ECB searches only in areas with medium to high density of Bursaria. The total survey effort or time spent searching for ECB in this period was 187 hours.

Our ECB habitat mapping and adult ECB records were all shared with DELWP, and a few members of the monitoring group met with Fire Operations Staff of DELWP, Bendigo prior to their Autumn 2020 burn in the hope that they could carry out the burn without burning the 8 ha of ECB habitat. A large area of Kalimna Park was burnt, including patchy burns where some of the larger ECB colonies occur.

ECB at the Castlemaine Botanical Gardens update

Mount Alexander Shire Council have funded for the second year in a row, a survey of Eltham Copper Butterflies that in the northern section of the Botanic Gardens. Seven transects were established in this area in 2010 and were surveyed by DELWP from 2010-2012. MASC then resurveyed these transects in 2019 and again this year. Historically the botanic gardens ECB population provided evidence that ECB populations may move up to several hundred metres depending on local environmental conditions. Previous studies of the gardens ECB indicated that they occurred on one of two ridges and that they moved from one ridge to the other. I was always dubious as from my three years of surveys they were only ever seen on the western ridge. So I was shocked last week to find that the only ECB I saw were on the eastern ridge! However given that there has been a large number of years where the site was not surveyed, more consistent observations over time will support this. This is more evidence that we need to protect not only where ECB occur but surrounding habitat that can support them so they can shift when conditions no longer support them.

Getting involved this summer

If you would like to join the ECB monitoring group to help survey for the butterflies and their host Bursaria plants, please contact Elaine: rakali@outlook.com.au.

For information about the Eltham Copper Butterfly and its identification, see: https://connectingcountry.org.au/education-resources/eltham-copper-butterfly-in-central-victoria/

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 has some excellent footage of this wonderful butterfly and symbiotic ant species.