The current fires are unprecedented in scale and intensity and as we come to terms with the ecological impact of these fires, Alluvium’s Rob Dabal shares his experience witnessing the impacts and recovery, including on his own property at Kinglake which burnt on Black Saturday in 2009. At the time, Rob was a Senior Vegetation Specialist at Melbourne Water. Along with Dave Carew who was also at Melbourne Water and is currently with Alluvium, Rob advised on vegetation recovery along waterways.
My first insight into the severity of the Black Saturday fires came from a conversation with a friend of mine who was is a Park Victoria ranger. On the evening of Black Saturday, he described the scene of devastation and what remained of the forest that once surrounded Kinglake: “It’s just sticks poking out of red dirt, it’s all gone”. Back then I owned a few acres on the top of the Kinglake range, a beautiful little north facing slope, about an acre of cleared land and a few acres of tall forest that sloped down to a permanent creek. Red mountain soil, giant Mountain Ash, tree ferns. I’d planned to build a little place there one day. It’s a familiar dream.
I’d always been aware that it might burn one day. But not with such ferocity. Driving up to my place a few days after the fire was confronting. Burnt out cars with melted engine blocks strewn out across the road like the police tape that was slung around them a day or two earlier. Contorted trees furiously twisted by the wind. Some so instantly desiccated that their leaves remained attached and extended to match the pattern of the wind that blasted across them. Big old Yellow Box snapped in half like feeble matches.
Arriving at my place it seemed that although it was totally burnt, it was not as hard hit as the slopes to our south which burnt when the wind changed and drove the fire uphill from Strathewen.
I returned every few days over the following weeks and months to observe the changes. The sheltered part of the property down by the creek began to show signs of recovery quite quickly.
Seedlings of Mountain Ash, Silver Wattle and sedges were the first on the scene germinating profusely by early March. The exotic species kicked in too. Clover germinated in places I’d never seen it before and so did many other fast-growing weeds and sprawling species like Blackberry.
Figure 1. Early signs of recovery a few weeks after the fire, Eucalypts, sedges, Acacia and clover seedlings emerge.
Over the next weeks and months, we began to see the landscape change and recover. Through my work at Melbourne Water, I assessed properties across the fire zone. To the south we were dealing with fire recovery in the Bunyip catchment. Dave Carew was my counterpart at Melbourne Water and is now also at Alluvium in our small ecology team.
Our response to the impact and recovery from these fires was complex. Dave and I were acutely aware of the human and ecological frailty we were dealing with. On occasions we approached our task with objectivity and recorded what we observed, but it was obvious that to respond to this ecological issue we had to listen to the needs of the community who’s land we were helping protect.
Figure 2. Ground ferns can recover quickly in some areas, Dave Carew conducting platypus monitoring in the Upper Bunyip catchment.
An overwhelmingly strong message from the communities we worked with was to offer assistance on their terms. People wanted to do something… but what? Our approach was to first listen to their issues and concerns and re-assure landowners that time would be needed to better understand the ecological response.
The openness of the landscape made assessing and accessing waterways very easy. It meant that tasks like controlling re-sprouting Blackberry could be easily undertaken. But the community’s need to respond had to tempered with a broader landscape view.
Figure 3. Colonising weed species can take advantage of bare ground post-fire and dominate where they previously were background weeds. Do they offer benefits as ground stabilisers?
Many colonising weed species took advantage of bare ground post-fire and dominated where they were once just background weeds. Leaving these species to protect the ground from erosion and to re-build the soil by replacing lost organic matter was important.
Reflecting on the current situation we would do well to first consider fire intensity. The intensity with which vegetation burns is a key driver of the landscapes capacity to recover. The Black Saturday fires ranged from low to very high intensity. Low intensity areas recovered quickly. Vegetation grew back and buffered the ground.
Understanding fire intensity across the landscape will help organise how and where we respond. However, our response will need to be informed by the changed conditions we now face. Critical differences will be residual soil moisture and how quickly this is replenished. The ongoing drying of our landscape due to climate change will undoubtably impact on how the landscape recovers. Some areas, given time, may return to their pre-burnt condition.It is likely that we will lose species of both flora and fauna, certainly at the local scale but potentially more broadly.
From our previous experience we have learnt how to apply strategic recovery efforts to rehabilitate ecosystems. Effect strategic approaches at this scale must be supported by creditable understandings of community and ecological values. Understanding these values puts us in the best place to develop appropriate responses to rapidly shifting nature of fire impacts driven by climate change.