Dr Orsi Decker1, Dr Nick Murphy1, Assoc. Prof. Pete Green1
1La Trobe University, Melbourne, Australia
Invertebrates are severely under-studied organisms in general, but when it comes to the ecology of land snails, the knowledge gaps are overwhelming. We have limited understanding of their dispersal capacity, population dynamics and responses to disturbances, such as fire. This is mainly due to insufficient survey effort and the low population density of many species. Using an eDNA approach could significantly improve our ecological understanding of land snails and other rare invertebrates. After the 2019/2020 Black Summer bushfires in Australia, we collected data on the impact of the fires on short-range endemic land snails and other invertebrates. It is clear from our post-fire surveys, that the detectability of live snails is very low in both unburnt locations and refuges within the fire boundary (such as large logs). We propose the use of eDNA as a method to survey land snails – and possibly other rare invertebrates – from soil samples under heavy logs and from bark scrapings of fallen trees. This method has opportunities to improve sampling efficiency (thereby reducing cost) and improve data amount/quality (allowing us to answer ecological questions that were previously out of reach). The collected eDNA samples from soil, bark and logs are currently being analysed to determine if species found near sampling points can be detected using eDNA. If this new approach proves feasible, we will be better able to untangle the responses to disturbance of many understudied endemic taxa and contribute to setting restoration and management goals in the future.
Biography:
My main interest is in small and sometimes invisible creatures beneath our feet: soil invertebrates and microbial organisms. They are playing crucial roles in our ecosystems; however, they are hardly recognised for their hard work. In my projects, I am trying to understand this underrated universe belowground and use our data to conserve and restore habitats from the ‘bottom up’.
After completing my PhD studies on Australian native mammals on soil processes, I stayed in Melbourne to work on various projects focusing on soil fauna, such as exploring the possibilities of invertebrate and microbe rewilding on farmlands; or studying the effect of prairie dogs in American grasslands. I am currently working on a Bushfire Recovery project looking at endemic land snail responses to the Black Summer fires.