Beetles used as biocontrol for ecosystem health
Little beetles with big appetites are proving part of the solution to combating invasive weeds in Southeast Queensland.

Ecologists at Healthy Land & Water are on the ground deploying biological control agents in the Lockyer Uplands and Little Liverpool Range districts to help protect habitat and keep ecosystems flourishing.

The beetles are being used to target cat’s claw creeper (Dolichandra unuguis-cati) and madeira vine (Anredera cordifolia) – both problematic invasive species – which are known for their prolific growth that smothers native trees and shrubs as well as understorey species within their reach.

Two species beetles are being used as a nature-based solution to these noxious weeds which pose a significant threat to habitat across the region.

The cat’s claw creeper jewel beetle (Hedwigiella jureceki) and the madeira vine beetle (Plectonycha correntina) which are used as part of an integrated solution to weed control – undermine the weeds’ strength, reducing seed production and creating space for native vegetation to thrive.  This solution is music to the ears of land managers and conservationists who have been struggling to control these difficult invasive weeds for a long time.

Categorised as transformer species, the impacts of madeira vine and cat’s claw creeper infestations on native vegetation are so severe that they can lead to irreversible  transformation and disruption to ecosystems. Both pest plants are commonly found in disturbed areas where they were once introduced as garden plants before escaping to invade vulnerable riparian vegetation and semi-evergreen vine thickets. Semi-evergreen vine thickets have been listed as endangered ecological communities in other parts of the state.

The loss of native vegetation increases landscape vulnerability to natural disasters and climate change, and reduces biodiversity and available habitat for native insects, birds, and animals.

Healthy Land & Water’s use these beetles is part of a multi-pronged approach. While some infestations can be brought under control with a careful mix of physical and chemical control techniques, the very nature of the smothering weed can make it difficult to access the infested sites or prove too labour intensive and expensive to tackle with physical control measures. This is where the introduction of biological control can be beneficial.

Where conventional control methods can be expensive, difficult, and very labour intensive, costs associated with raising and releasing biological controls remain relatively low.

Since December 2023, there have been 8,500 cats claw creeper jewel beetles and 3,300 madeira vine beetles released across the Lockyer Uplands and Little Liverpool Range thanks to the support of the Queensland Government’s Natural Resource Recovery Program as well as the collaborative efforts of project partners: Lockyer Uplands Catchments Inc, Little Liverpool Range Initiative, Lockyer Valley Regional Council, Ipswich City Council and Noosa & District Landcare Group.

Want to know more about how these beetles complement other weed eradication efforts?  Visit regional natural resource management (NRM) organisation – Healthy Land & Water’s website for all the details.