WA’s dying forests need urgent health monitoring as they face the impacts of climate change, according to experts in the field.
Murdoch University forest ecologist Joe Fontaine said just like in a coral bleaching event, large areas of vegetation across the state started to turn brown and die off in February.
Dying trees are evident in the jarrah forests in WA.Credit: Joe Fontaine
He urged the state government to support university-government partnerships to develop a system to monitor the health and determine the risks of future events on WA’s forests. Climate change was set to make large-scale plant die-offs more likely.
“The likelihood of WA’s event has been evident to scientists for months, yet there was no consistent monitoring or warning system in place to prepare the community or to influence behaviour such as groundwater use,” he said.
“The DBCA are monitoring impacts using satellite imagery and are actively collecting ground-truthing data with reports there is widespread concern among staff.
“Throughout the region many people are concerned and the levels of anxiety are high across the community and including the agricultural and forestry sector.”
Fontaine said the main driver of vegetation deaths were shallow soils.
“This means the plants are growing in thin soils overlying rock and run out of water first, for example, trees around the edges of granite outcrops or on the scarp,” he said.
“Also places where groundwater pumping has lowered the water table.
“Because it has been so dry there presumably has been a lot more pumping than normal, so it has amplified the impacts including on the coastal plain north of Perth around Gingin.”
In 2011, the northern Jarrah Forest that stretches from inland of Perth to Collie suffered a forest collapse – believed to be the first such event in the world – but in 2024, the damage is more widespread.
A DBCA spokesman said alongside universities they were studying the severity and size of the die-off using satellites, aircraft, drones and on-the-ground inspections.
It plans to map where vegetation was most vulnerable to die out and, in the longer term, thin the forest in these areas to reduce competition for water.
“The DBCA is aware of die-off occurring in several vegetation types across the south-west,” he said.
“There are similarities to the 2011 die-off event, in that it is being recorded in some parts of the Northern Jarrah Forest, particularly in shallow soils around granite outcrops.
“Of the sites visited, species affected include jarrah, marri, flooded gum, bull banksia and sheoak in the forest, and understorey species in coastal locations.”
The spokesman said during these periods of long, hot and dry summers, there were no short-term or immediate opportunities to undertake reactive management to address significant, landscape-wide events already underway.
WA Greens MLC Brad Pettitt said we were witnessing a devastating ecosystem collapse that was likely to accelerate the loss of many of the state’s unique and globally significant species and ecosystems.
“South-Western Australia is drying out and dying off at one of the fastest rates in the world; so fast that we are watching it happen in real time,” he said.
“This unprecedented heat and drought - driven by global warming and caused by the burning of fossil fuels - follows warnings by the IPCC of the potential collapse of the Northern Jarrah Forest.
“Not only has the Cook government so far failed to acknowledge this fact but they’ve ramped up calls for more gas development at the behest of corporations like Woodside as WA’s emissions continue to rise.
“For the sake of our forests, our native wildlife and our own future it’s time to get serious about climate change, legislate a binding emissions reductions target in line with the science and commit to no new gas.”
Environment Minister Reese Whitby said the browning event was the result of climate change.
“I was down in Margaret River a couple of weeks ago and I could see the browning off of the canopy, I could see dead trees, I could see dead banksia bushes, it’s a real concern” he said.
“It’s evidence of why we need to act on climate change ... and the government’s ambition is to get to net-zero by 2050 reducing our reliance on coal and transitioning out of coal in 2030.”
The State Government announced $65 million in funding last month for 65 jobs within the DBCA and partner agencies focused on a range of climate actions including a new forest health monitoring program and support for emerging technologies, such as fire research, and ecological thinning.
Residents can report dead trees as part of a new citizen science project, The Dead Tree Detective to help researchers monitor the health of trees and ecosystems.
Start the day with a summary of the day’s most important and interesting stories, analysis and insights. Sign up for our Morning Edition newsletter.