Ecological Society of Australia 60Th Anniversary Conference 30 November – 4 December 2020 Page 1 of 139
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Book of Abstracts Ecological Society of Australia 60th Anniversary Conference 30 November – 4 December 2020 Page 1 of 139 Once bitten twice shy: Using Taste Aversion to protect wild Freshwater Crocodiles from Cane toads. Miss Abhilasha Aiyer1, Dr. Georgia Ward-Fear2, Prof. Rick Shine2, Dr. Ruchira Somaweera3, Assoc. Prof. Tina Bell1 1The University of Sydney - School of Life and Environmental Sciences, Sydney, Australia, 2Macquarie University - School of Biological Sciences, Sydney, Australia, 3CSIRO, Perth, Australia SYMPOSIUM: Behavioural response to ecological challenges (1) - Abhilasha Aiyer, December 1, 2020, 10:00 - 12:05 Biography: Abhi is an Honours candidate at the University of Sydney with a passion for applied conservation research and threatened species management. Her current project involves designing practical solutions to ecological challenges; namely using animal behaviour to mitigate against invasive species. In Northern Australia, invasive Cane toads have caused large population declines in anurophagous predators including: quolls, varanids, large elapids and freshwater crocodiles. Conditioned Taste Aversion therapy (where a subject associates the taste of food with nauseous symptoms caused by an imbedded chemical) has been utilised as a conservation intervention to mitigate toad impacts. But to succeed, deployment strategies need to consider the behaviour, physiology and ecology of the target predator (and potential nuisance species). In a first, we trialled bait deployments with wild Freshwater Crocodiles (Crocodylus johnsoni) in-situ to develop best practice protocols for landscape level training ahead of the Cane toad frontline. We designed a custom baiting apparatus for deployment around waterbodies and investigated how bait placement and timing influenced bait uptake by crocodiles and non-target species. Of all baits consumed (16%), 70% were taken by off-target species (varanids = 12%, raptors = 22%, meat ants 35%). However, the location of the bait along the apparatus significantly determined species visitation (P<0.0001). Crocodiles favoured baits positioned over the water (80%), versus the water’s edge (15%) or bank (5%) and constituted 84% of all water baits taken by all species. Contrary to expected, crocodiles actively foraged both diurnally and nocturnally, however foraging behaviour differed significantly for other predators (P<0.05). Our results also suggest that local ecological factors including food availability and vegetation cover influence bait uptake, as does bait age. We discuss the broader implications of our study in developing species-specific baiting strategies for the conservation of vulnerable reptilian predators. The Hitchhiker's Guide to Post-Heatwave Seed Germination: Don't Panic! Miss Philippa Alvarez1,2, Dr Brad Murray1, Dr Cathy Offord2 1University of Technology Sydney, Ultimo, Australia, 2Australian Botanic Gardens, Mt Annan, Australia SYMPOSIUM: Temperature Extremes: impacts, resilience and mitigation (Thermal Tolerance) - Philippa Alvarez, November 30, 2020, 10:00 - 12:00 Biography: Philippa has just completed her Masters in Science (Research) at the University of Technology Sydney. She hopes to continue her studies with a focus in ecology and the effects of climate change on plants, specifically seeds. Page 2 of 139 Human-induced climate change is the primary source of a global increase in temperature and a global increase in extreme weather events such as heatwaves. Heatwaves are increasing in intensity and frequency causing detrimental changes to plant communities worldwide, with the temperate woodlands in southeastern Australia as no exception. Native plant species in the Cumberland Plain Woodland (CPW) are expected to see an increase in high intensity and frequent heatwaves, leaving the most vulnerable aspect of the plant lifecycle, the seed, at risk of changing the biodiversity of this threatened ecological community. In this talk, I aim to understand the link between the physiological mechanisms behind seed germination and the ecological context of these species to understand the future plant community composition of the CPW region. My results showed that species were more resilient to the heatwaves with no significant effect of treatment on the species, however, I did find a species x treatment interaction and a significant effect of species. A few species were found to be driving the species x treatment interaction and so, with this information, I decided to delve deeper into the underlying mechanisms causing this interaction through a study into the life-history traits of species. I found that life-history traits were related to the interspecific patterns of variation in all three germination attributes with life form having the greatest influence over seed germination, seed mass and dormancy both also influencing germination attributes to a lesser degree and fire response only partially influencing germination attributes. Soil microbial succession after fire in logged Tasmanian wet eucalypt forests Mr Hans Ammitzboll1, Prof Greg Jordan1, Dr Sue Baker1, Dr Jules Freeman2, Dr Andrew Bissett3 1University Of Tasmania, Sandy Bay, Australia, 2Scion, Rotorua, New Zealand, 3CSIRO, Hobart, Australia SYMPOSIUM: Soil microbial responses to climate extremes: mechanisms, patterns, interactions - Hans Ammitzboll, November 30, 2020, 10:00 - 12:00 Biography: Hans is a current PhD student at UTAS where he is using molecular techniques to study the effects of logging and burn severity on the composition and succession of soil bacterial and fungal communities We investigated the community composition and abundance of bacterial and fungal soil microbes across a burn severity gradient one-, six-, and twelve-months post-fire in logged temperate wet eucalypt forests in Tasmania, Australia. We used next-generation sequencing and real-time qPCR of bacterial 16S and fungal ITS1 rRNA to calculate the composition and abundance of soil microbial communities. We demonstrate that i) burn severity remains a strong driver of soil microbial community compositions twelve-months post-burn, ii) bacteria and fungi rapidly recover biomass lost due to high-intensity burning, and iii) fungi are more sensitive to the impacts of logging and burn-severity than bacteria. Our research suggests that succession is occurring relatively quickly in bacterial communities, but fungi require more time to recover to a post-disturbance state. Understanding how the recovery of these soil communities relates to the regenerating vegetation will be critical for elucidating links between aboveground and belowground ecology. Faunal responses to fire in Australian tropical savannas: lessons from field experiments Professor Alan Andersen1 1Charles Darwin University, Darwin, Australia SYMPOSIUM: Perspectives on a changing landscape of fire (1) - Alan Andersen, December 1, 2020, 10:00 - 12:15 Biography: Page 3 of 139 Alan Andersen is a University Professorial Fellow at Charles Darwin University. He has conducted research on fire in Australian tropical savannas for three decades, including playing leading roles in the Kapalga and TWP fire experiments and the Tiwi Carbon Study. Fire is particularly frequent, complex and contentious in the vast tropical savannas of northern Australia, where declines in many threatened species are associated with fire, and substantial areas are under fire management for greenhouse-gas abatement. Here I present key insights into faunal responses to fire in Australian tropical savannas that have been revealed by controlled field experiments, along with their lessons for fire management. The key insights are: (1) Most faunal groups are remarkably resilient to fire; (2)The most important effects of fire are typically indirect through habitat modification, even when there is substantial direct mortality; (3) Fire intensity is not as important a factor as is widely thought; rather, the most important component of fire regimes appears to be fire frequency; (4) There will always be winners and losers with any fire; and (5) Fire is required for the maintenance of diversity. A combination of frequently (every 2-3 years) and less frequently (every ≥5 years) burned habitat may adequately conserve the great majority of animal species in Australian tropical savannas without a need for complex fire mosaics. Special management attention is required for frequent-fire losers because of an extremely low representation of longer-unburnt habitat. The insights are widely applicable to tropical grassy ecosystems more generally, and some – the importance of indirect effects through habitat change, the trade- off between fire winners and losers, and the overall importance of fire in maintaining biodiversity, are also widely applicable to other fire-prone biomes. Ecophysiological mechanisms underpinning resilience to climate change in the Northern Jarrah Forest (Western Australia) Mr Nate Anderson1,2, Dr Joe Fontaine2, Dr Lewis Walden3, Dr Wolfgang Lewandrowski1,4, Dr Katinka Ruthrof5 1Kings Park Science, Perth, Australia, 2Murdoch University, Murdoch, Australia, 3Curtin University, Bentley, Australia, 4University of Western Australia, Crawley, Australia, 5Department of Biodiversity, Conservation and Attractions, Kensington, Australia SYMPOSIUM: Perspectives on a changing landscape of fire (1) - Nathan Anderson, December 1, 2020, 10:00 - 12:15 Biography: I am an honours student at Murdoch University and based out of Kings Park. My research focuses on forest responses to disturbance (drought and bushfire) after