Gathering gourmet gum leaves for Redlands Coast koalas

Koalas are one of the most iconic and beloved animals in Australia and their protection is a top priority for Redland City Council. A unique research project, involving a collaboration between Council and the Australian National University, is looking specifically at the nutritional quality of what these cuddly marsupials eat. Dubbed the Gourmet Gum Leaves project, it is aimed at improving landscape nutritional quality which will assist in koala conservation and management.

Researchers onsite at Birkdale Community Precinct

The throw-line launcher’s weighted bag whistles up into the canopy of the gum tree, loops over a small branch and bends its whitish stem. A rope is twisted to the side, it goes taut … crick-crack … and the branch and its leathery, laurel-green foliage drops in a slow spiral.

It is certainly not a high-tech piece of research equipment, but the launcher beats physically climbing the tree to hand-pick seven or eight suitable branches from as many trees in one collection day. This way the pair of research scientists conducting this work for the Australian National University (ANU) can collect samples from more than 30 trees in a day.

“It works really well when you have the skills to be able to use it,” says one of the launcher’s operators, Dr Christina Zdenek, with a grin as she retrieves the downed branch from the ground, deep inside the conservation bushland area of Birkdale Community Precinct. “It is very efficient.” And also a little fun judging by that grin.

Researchers Dr Christina Zdenek and James Skewes working at Birkdale Community Precinct. To watch the team in action, click here

Dr Zdenek, a Queensland ecologist working for The Australian National University, and her fellow researcher and launch buddy James Skewes, a Queensland-bred ecologist who has flown up from his current base at Canberra’s ANU for this job, are part of a unique research project that is looking into the nutritional quality of the leaves of koala food trees.

Dubbed the Gourmet Gum Leaves project, it is a collaboration between Redland City Council and ANU, and is aimed at improving landscape nutritional quality which will assist in koala conservation and management.

The collection of leaves from the eucalyptus species in Birkdale Community Precinct is part of the project’s first phase, which involves vegetation surveys, mapping and evaluation of the nutritional quality of leaves from about 160 trees at the site.

Seeds are also being collected from up to 30 koala food trees on Redlands Coast and nearby locations in south-east Queensland known to have relatively high nutritional quality.

These seeds, according to Mr Skewes, will be propagated at Redlands IndigiScapes Native Community Nursery at Capalaba and grown into seedlings for future planting at the Birkdale Community Precinct site which currently sustains a small but significant koala population.

“We’ve got a few areas that have been pinpointed for planting,” says Mr Skewes. “And the seeds are collected from trees that we’ve already got strong data on; so we already know that they’re nutritious for koalas. It will be really good to eventually see them planted on site here.”

Research ecologist James Skewes with some leaf samples from Birkdale Community precinct being collected as part of the Gourmet Gum Leaves project.

ANU College of Science Research Fellow Kara Youngentob says the aim is to recommend a targeted revegetation strategy.

“One of the most important factors influencing the distribution and numbers of koalas in any area is the quality of their food trees,” says Dr Youngentob. “This pilot ultimately intends to increase the local koala population by providing a higher quality food source by growing high nutritional quality koala food trees.

“Better quality habitat for koalas results in healthier more robust populations, that are more likely to produce healthy young who will thrive.”

It is not only koalas who benefit.

“Ultimately, projects like these also help to restore and rebalance the landscape for all native species both flora and fauna,” says Dr Youngentob. 

“The ultimate goal of most wildlife conservation programs is to improve the long-term viability of populations in the wild. The capacity for nutrition to contribute to this goal is often overlooked due to difficulties of measuring nutritional landscapes.

“However, landscapes with higher nutritional quality are likely to support larger populations of herbivores, and animals with access to high quality foods are more likely to be resilient to environmental change.”

As she picks healthy leaves from the fallen branch, weighs them, dates and files the samples away, Dr Zdenek says the long-term benefits of improving the nutritional landscape through the Gourmet Gum Leaves initiative, are being supported in the shorter term by Council.

Researcher Dr Christina Zdenek working at Birkdale Community Precinct.

“Preserving old growth trees and conservation areas at Birkdale Community Precinct is fantastic. It’s really best practise management,” she says.

“Obviously we’re amid a global biodiversity crisis, as people are probably aware, sadly, and that’s no different across Australia where we’re losing many species and even in Queensland.

“The idea is to think global but act local. And that’s exactly what we’re doing here. Then on top of that, using evidence-based information and science to improve that landscape into the future, to give the koalas and other species a fighting chance.”

From a safe distance, Redland City Mayor Karen Williams and Council’s Principal Adviser (Community Education) Stacey Thomson are watching the researchers in action, having trekked their way into the bushland, within cooee of Tingalpa Creek. About two-thirds of the 62-hectare Birkdale Community Precinct is protected conservation area.

Research ecologists Dr Christina Zdenek and James Skewes with Council’s Principal Adviser (Community Education) Stacey Thomson and Redland City Mayor Karen Williams.

Cr Williams says the Gourmet Gum Leaves project and other initiatives on the site have intergenerational aspirations.

“What makes me most proud is that we’re not only just protecting this unique environmental area, we’re actually enhancing it so that future generations can not only enjoy this space, but learn from our unique environment,” she says.

Ranger Stacey agrees. “It is protecting and enhancing, that’s what it is all about,” she says. “This research is something that will give hope to our koalas in the future, and they deserve it!”

Acting globally to reverse the biodiversity crisis may feel like a long shot, but with the launcher tensed for another flight up into the gum tree’s canopy, the goal locally is certainly within sight.