Out of the ashes: Post-bushfire lessons on how we can better manage our fauna

In September 2021, the Royal Zoological Society of NSW held their annual forum online – receiving more registrations than ever before, with a tremendous range of talks focused on the impacts of the 2019-20 megafires and post-bushfire management.

The Royal Zoological Society (RZS) of NSW was due to host its annual forum in September 2020 at the Australian Museum, but due to COVID-19 restrictions the RZS held the forum online this month. At this forum, papers were presented by people from universities, government departments, consultancies, and environmental groups. Over 200 people registered from all over Australia, more than the RZS has ever had attend for any of the previous forums.

A tremendous range of talks on the impacts of the megafires in 2019 – 2020 was presented. These fires affected much of the east coast of Australia and southern Australia and many talks highlighted the effects of the preceding drought and described how habitats, which were previously thought to be resilient, were burnt severely (e.g. wet forests, some rainforests). The papers focused on a range of invertebrate species, birds, amphibians, bats and other mammals impacted by the fires, including some pest species such as feral cats and the cane toad that actually benefitted from the fires.

Many of the studies relied on data from pre-fire surveys, particularly the northern NSW forest surveys conducted by Australian Museum staff in the 1990s, which were initiated by Professor Gerry Cassis. Based on these surveys, research teams from UNSW and the Australian Museum resurveyed the historical sites to assess the impact of the megafires on a range of invertebrate surrogates. Dr Frank Koehler, Junn Kitt Foon, Dr Chris Reid and Aidan Runagall-McNaull of the Australian Museum investigated if species of molluscs and beetles (Coleoptera) had been lost in the fires. From UNSW, Dr Ryan Shofner, Dr Marina Cheng and Professor Gerry Cassis investigated fire impacts on true bugs and Professor Shawn Laffan leads a project undertaking spatial analysis of the above invertebrates, which is ongoing.

Similarly, pre-fire baseline surveys of the fauna of Kangaroo Island in South Australia were critical for assessing the impact of fires in this area, as many endemic species occur on Kangaroo Island. While obtaining funding for such baseline surveys is not always easy, these surveys are critical for the ongoing assessment of fire and other environmental impacts. They must be continued to document the recovery of burnt ecosystems, including long-term monitoring of all ecological components. The forum highlighted the importance of long-term monitoring programs. One such example was the monitoring of yellow-bellied gliders in southern NSW, where surveys have continued since 1995 and the fires, especially where severity was high, were shown to have impacted the population.

While the press coverage during the time of the fires suggested almost complete devastation, many papers provided evidence that, while habitat was burnt, this was not equal to it being destroyed. Subsequent good rainfall has also helped in some restoration of habitat. However, the loss of large, old hollow trees is of key concern to those animals which use them for nesting. It takes decades, even centuries, for trees to develop such hollows. Other key components of the forest that will take a long time to recover are large old logs and deep leaf litter. So, while some recovery is occurring, much more research is needed to monitor how quickly key forest components return and to determine if all species can rebuild their populations.

The initial reports from the forum, the proceedings of which will be published in the Australian Zoologist in 2022, stress the importance of looking at all the components of the ecosystem. However, there was a significant gap in the presented research - no papers were presented on changes in the soil fauna, which presents a future research imperative. It is also critical that we continue to document this recovery over time; not only in the eucalypt forests, but in the rainforests thought previously to be immune to fires. Given that climate change is predicted to increase the frequency and intensity of fires as well as periods of severe drought, such long-term studies are needed to try and protect the future of our fauna and flora. This was the subject of a previous RZS forum and the theme edition of Australian Zoologist published in 2018.

The published papers will provide more detail on lessons learnt from the fires, especially on how to improve risk management and ecological recovery associated with inevitable future fires. From the brief presentations at RZS, it was apparent that future management must include control of land clearing, the encroachment of urbanization into bushland and proposals for new mines and changes to water catchments.

Although it is uncertain as to when we can have in-person forums, the ability of scientific societies to meet in the ether, despite the many hurdles of the pandemic, is certainly a positive! A mixture of live talks and zoom talks may be the way of the future – and we hope that the lessons from the RZS forum continue to engage more audiences, spur on further scientific discovery and initiate future risk management programs.

Dr Pat Hutchings, Senior Fellow, Marine Invertebrates, Australian Museum; and, Member of the Forum Committee of Royal Zoological Society (with Chris Dickman, Brad Law, Dan Lunney, Tom Newsome and Ricky Spencer).