2019 Tasmanian Fires: Impacts and Management Lessons
By Prof. David Bowman
The widespread rains that fell on 7 February and subsequent cooler weather hopefully will alleviate the 2019 Tasmanian fire crisis. It is timely to take stock of this event and consider what bushfires ignited by massive dry lightning storms means for fire management of the Tasmanian landscapes, including the Tasmania Wilderness World Heritage Area (TWWHA) that cover around 20% of the State.
Over 40 fires burnt almost 3% (c. 200,000 ha) of the island of Tasmania in January 2019, nearly all ignited by lightning storms on 28 December 2018, 16 January 2019 and 29 January 2019. The fires occurred both within and outside the TWWHA.
Contrary to widespread concerns the fires did not have a devastating impact on iconic Gondwanan vegetation in the TWWHA. Preliminary analyses suggest overall only 3.2% of the area burnt was in rainforest and 4% was highland treeless vegetation (although much of this is fire-adapted). The reason so much of this irreplaceable Gondwanan vegetation was spared was because fuel moisture was higher than in surrounding flammable vegetation due to rainfall in the early summer. Had the drought been more protracted (such as occurred in 2016), then more of the vegetation would have been destroyed. Next time Tasmania may not be so lucky if widespread dry lightning saturates the island during a prolonged drought.
The lion’s share of burnt vegetation was in fire-adapted vegetation (21% in dry eucalypt forest, 26% in wet eucalypt forest and 32% in open moorland ‘button grass’ vegetation). All these three vegetation types will recover from fire; however, the rate will depend on the severity of the fires (i.e. how comprehensively the canopy has been scorched or defoliated).
I suspect the tall old growth eucalypt forests are little effected by the fires because they did not burn under extreme fire weather conditions hence only the understory has burnt. However, younger eucalypt forests regrowing after logging appear to be completely defoliated. Reportedly large areas of forest regrowth and plantation have been destroyed, and while the exact scale of the impact one these forestry resources awaits determination, available figures suggest 35,325 ha of the private forest resource have been burnt, including 3,239 ha of eucalypt and 533 ha of pine plantations. The loss of forest resources will place particular pressure on hardwood and specialty rainforest timber supplies in the coming years and may well spark renewed environmental disputes.
Apiarists are also concerned that the combined effect of the drought and the burning of understorey vegetation in the wet eucalypt forests will greatly reduce honey production, particularly the leatherwood honey unique to Tasmania. It is essential mapping of fire severity is undertaken to appraise the scale of the impact on the forest resources.
The fires had greatest impacts of Tasmanian society. Many small communities were evacuated, and road blocks impacted small business. Chronic air pollution affected the capital city Hobart and numerous smaller communities in the Huon Valley, prompting smoke alerts from the Tasmanian Health Department. There was widespread community anxiety about the fires, including people stressed about the potential impact of the fires on the Tasmanian Wilderness. There were rolling closures of National Parks and bushwalkers were evacuated from remote areas as a precautionary measure. There were concerns the disruptions affected the Tasmanian tourist ‘brand’.
Fighting fires in remote areas in Tasmania is challenging given the rugged terrain and inaccessibility, so options are limited. This must be understood in commentaries about the effective of the firefighting response to these fires. The Tasmanian Government Review into the 2016 Wilderness fires by Dr Tony Press lists the most effective firefighting methods in wilderness areas:
- Letting fire burn without suppression
- Rapid attack using firefighters transported by helicopter
- Aerial bombing with firefighting chemicals
- Machine or hand cut fire breaks
- Irrigation using hose and sprinklers
All these approaches were used in the 2019 firefighting campaign. It is important to note that each has downsides: Letting fires burn unchecked can damage sensitive vegetation; firefighting chemicals can cause aquatic pollution; mechanical fire breaks can cause erosion and the spread of weeds and pathogens; irrigation depends on and reduces available water supplies; wilderness firefighters require specialist training and appropriate aircraft and supporting infrastructure. With the exception of the ‘let it burn approach,’ all these management interventions are economically costly.
The above constraints are recognised in Press’s Report.
Accordingly, he made eighteen important recommendations to improve fire management in the Tasmanian wilderness, all of which resonate in light of the 2019 fires. Key elements of Press’s recommendations are the need for:
- Clearly stated management and planning objectives identifying how fire management and firefighting can conserve and protect the natural and cultural heritage values in the TWWHA.
- More accurate mapping of natural and cultural resources to help prioritise suppression efforts.
- Improved effectiveness of firefighting through better surveillance and detection of fires, and enhanced rapid response to fight fires.
- Greater investment in remote firefighting, including training (and considering role of volunteers), equipment aircraft support.
- Development of evidence-based protocols for the use of firefighting chemicals.
- Effective dissemination of public information about remote area fires, including their scale, ecological effects and management responses.
- Evaluation of the effectiveness of planned burning program based on monitoring and research of ecological impacts.
- Increased understanding and adaptive management responses to the effects of both climate change and fire on the region’s ecology
In the inevitable post-mortem into the 2019 Tasmanian fire crisis, Dr Press’s 2016 report represents an invaluable baseline from which to measure progress made in wilderness fires management. Given the increasing occurrence of lightning ignited bushfires due to climate change such benchmarking is essential step in adaptation to more frequent bushfire and also helps frame the necessarily political and social debates about future economic investment for fire management and firefighting in the Tasmanian wilderness.
Photos courtesy of Luke Tscharke/Climate Council