Dr Emily McColl-Gausden1,3, Josh Griffiths2, Dr Andrew Weeks1,2, Dr Reid Tingley2,3
1The University Of Melbourne, Parkville, Australia, 2EnviroDNA Pty Ltd, Brunswick, Australia, 3Monash University, Clayton, Australia
Species presence-absence data collected over large spatial extents can be time consuming and logistically difficult to obtain. Yet these data are important for ensuring changes in species distributions are accurately monitored and are vital to our understanding of how species respond to global change. Here we demonstrate the use of environmental DNA (eDNA) sampling for collecting species occupancy data across vast spatial scales. We used a systematic environmental DNA sampling regime to survey platypuses at 504 sites across 584,292 km2 of south-eastern Australia. Site occupancy detection models were used to analyse how landscape- and site-level factors affect platypus occupancy, enabling us to incorporate uncertainty at the different levels inherent in eDNA sampling (site, water sample replicate, and qPCR replicate). Platypuses were more likely to occupy sites in catchments with increased runoff, less zero-flow days, and access to banks suitable for burrowing and were less likely to occupy sites in catchments with a higher proportion of shrubs and grasslands. We demonstrate that eDNA sampling can be conducted efficiently over large spatial scales and that this data can be used to understand how landscape or site characteristics affect platypus species occupancy. These methods can be applied to aquatic and semi-aquatic species monitoring globally, providing unprecedented opportunities to understand biodiversity change.
Biography:
I am a research fellow the University of Melbourne and Monash University. I am working on various projects involving eDNA data such examining as the impact of the 2019/2020 mega-fires. My PhD investigated using environmental DNA sampling as a tool for monitoring freshwater vertebrates and I am very interested in using quantitative methods to solve ecological problems.