Since 2021, Perth has been under a serious threat from the invasive polyphagous shot-hole borer. This destructive tree-killing beetle is a serious threat to the region’s ecology. The state’s authorities have been striving to contain the pest, which has an alarming growth rate even in Perth’s less-than-ideal climate conditions. Just last week, it reached new heights when a beetle deforested an island at Hyde Park. This unfortunate event led to increased scientific study to fight the embodied invading force.
To address this ecological disaster, our own Professor Ben Phillips is leading the charge on two new, innovative approaches to combat the borer. He’s experimenting with a chemical injection into infected trees and using commercially available nematodes that eat the beetles. These approaches aim to mitigate the threat of damage stemming from the polyphagous shot-hole borer. To protect crops and communities, they’re assisting to develop a clear picture of how this pest proliferates.
The state government has immediately acted in this case, having removed 4,794 trees infected with the polyphagous shot-hole borer. This campaign has been focused on some of Perth’s most loved green spaces including Kings Park, Hyde Park, and Stirling Gardens. This extreme step underscores how serious the threat from this invasive species has become.
Understanding the Threat
The polyphagous shot-hole borer came to Perth through, as Professor Phillips put it, “sheer dumb bad luck”. He argued that Perth’s climate is not suitable for the beetle to thrive. Yet its high reproduction rates have made containment efforts extraordinarily difficult.
“The beetle is the vector, and the fungus is the killer of trees, and different tree species seem to be varying considerably in their susceptibility,” stated Treena Burgess, an expert in tree health management. This clue may underscore the difficulty of addressing the bug’s invasion. As Lindgren explains, each tree species has a specific immune response to the borer and its associated pathogens.
The seriousness of this issue has led to cooperation among all parties, including universities and research institutions. They are pooling data as it becomes available, driven by an acute need for information on the polyphagous shot-hole borer’s spread and impact.
Innovative Research Initiatives
The Western Australian government has committed $2.17 million to fund three significant projects aimed at understanding and combating the polyphagous shot-hole borer over a three-year period. The WA Agriculture Research Centre (WAARC) will lead the research. Their objectives are to further improve trapping methodologies and develop enhanced strategies for controlling this invasive pest.
One example among many is Professor Paul Barber’s ArborCam project. This novel project aims to measure tree health in the face of the polyphagous shot-hole borer. “It will allow us to benchmark the health of the trees, and it can even differentiate between species, which is very important for things like the polyphagous shot-hole borer,” explained Paul Barber. ArborCam intends to make this data more widely and directly available online. We hope this resource will equip all stakeholders and researchers working to combat this ecological menace.
In his own words, here’s what Professor Phillips is currently doing to create models. These models will aid in predicting the potential future spread of the polyphagous shot-hole borer throughout Perth and further afield. He’s evaluating how well existing detection methods are working for the pest to help improve the response strategy.
Collaborative Efforts and Future Directions
ArborCarbon, a key player in biosecurity responses, has already taken steps to address the polyphagous shot-hole borer in eastern states. Their on-the-ground experience and knowledge is undoubtedly invaluable as they work hand-in-hand with Perth’s researchers to devise the best possible control measures.
The sense of urgency to combat this invasive species is felt deeply among researchers and stakeholders—scientists, state officials, fishermen, educators. “The purpose of this is to solve the problem,” said Treena Burgess, highlighting the collective commitment to restoring Perth’s green spaces. As new innovative research pushes the frontier of data availability, there is hope that an alternative solution will be just around the corner.
