A repository of biodiversity information

After the 2019-2020 megafires, scientists from the Australian Museum Research Institute were some of the first to return to the bush to face the aftermath, with biodiversity loss front of mind. These bushfires prompted a major investment into biodiversity monitoring across the country.

Biodiversity impact of the 2019-2020 megafires, published in Nature last week, is the outcome of many different research projects, synthesised to find broad trends and outliers across groups of organisms. The expansive taxonomic, ecological and geographic scope of this study enabled deeper exploration of how biodiversity responds to fire than has been possible previously.

Fire is not an unknown variable across the continent; many Australian plants and animals can deal with bushfires and have adapted over millennia to do so. However, the outcome of this collaborative paper shows that the biggest difference between historical and current bushfires on biodiversity loss was their extent and intensity. The research paper attempted to show how these fires impacted different organisms.

Led by Don A. Driscoll from Deakin University, supported by Dr Chris Reid, Dr Frank Köhler, Junn Kitt Foon and Dr Ryan Shofner from the Australian Museum Research Institute, and involving collaboration with a multidisciplinary group of researchers from all over the country, this new research has provided an unparalleled opportunity to quantify how megafires affect biodiversity and how we can minimise their disastrous effects in the future.

Of the 2000 taxa surveyed in the paper, AMRI scientists contributed data for 134 land snail and slug species, and 43 beetle species.

As the holders of Australia’s oldest historical biodiversity data, museums are an important repository of biodiversity information, and at the forefront of tracking change over time. The Australian Museum holds over 22 million specimens, the largest collection in the Southern Hemisphere, and as Australia’s oldest museum, has been collecting data for more than 190 years.

In the 1990s, the Australian Museum was involved in extensive surveys of the invertebrates of NSW forests, on behalf of NSW National Parks and Wildlife Service. The collections made from those surveys formed the basis for the Museum's post-fire surveys. These post-fire surveys were funded by the Federal Government through the University of New South Wales.

The impact of the 2019-2020 fires on biodiversity was on a scale not seen since records have been kept. The 2019-2020 megafires burnt 10.3 million hectares of bushland, including the largest documented area ever burnt at high severity. This paper reveals that the largest negative effects on plants and animals were in areas with frequent or recent past fires and within extensively burnt areas. Areas burnt at high severity, outside protected areas or under extreme drought were also badly affected.

AMRI scientists have been researching the smallest creatures to determine the largest biodiversity impacts of megafires. Invertebrate taxa like beetles and snails make up 75% of terrestrial species, and the trends identified from studying them can tell a broader story about the scale of biodiversity loss and renewal across fire ravaged areas of NSW.

Concerning snails, Dr Frank Köhler and Junn Kitt Foon found that the 2019-2020 megafires greatly impacted land snail populations not only because vast numbers were killed, but also because fire forced the surviving population to contract away from uninhabitable areas.

Regarding dung beetles, Dr Chris Reid and his team found that there was significant negative impact of the fires on flightless species, most of which are confined to rainforests. But some rainforest species were not re-discovered, suggesting that the prolonged drought which led to the fires had also had an impact.  Winged dung beetles are mostly found in fire prone dry forests and were not significantly affected.

Reversing anthropogenic climate change remains the clear, urgent and broad-scale solution to the overall impacts, and Australia’s Natural History Museum Directors collectively recognised this, urging the government to allocate essential funding to this as a priority, writing “The time to act is now and the nation’s natural history museums are ready to respond.”

However, there are also immediate measures which can be taken to ensure the care and maintenance of Australian biodiversity in the face of increasingly frequent megafires.

“With increasingly severe fire weather, a range of counter measures are needed, tailored to specific ecosystems,” the researchers involved in Biodiversity impact of the 2019-2020 megafires suggest. “Indigenous fire practices that place the right fire regimes into the right country, are therefore increasingly important for improving fire management for biodiversity conservation.”

AMRI’s Dr Frank Köhler adds that returning the bush to as close to its original state as possible is the best way to ensure that bushfires only burn at a level that the environment can bounce back from.

Overall, the combined research found that sites with three or more fires in the 40 years preceding 2019–2020 had negative effects that were 87–93% larger compared with sites not burnt or burnt only once over the same period. Without a substantial period of growth, renewal and time to seed, the effects of biodiversity loss are difficult to recover from. Even where prescribed backburning in Australian forests has reduced the severity of wildfire, large declines in biodiversity are still likely if past fires were recent or frequent.

Biodiversity impact of the 2019-2020 megafires is a collaboration between 126 researchers from 37 institutions, with Australian Museum biodiversity data at the centre of the historic change analysis.