Mr Austin Guthrie1, Dr Paul Nevill1, Dr Christine Cooper2, Dr Phillip Bateman3, Dr Mieke van der Heyde1
1Trace and Environmental DNA (TrEnD) Laboratory, School of Molecular and Life Sciences, Curtin University, Perth, Australia, 2School of Molecular and Life Sciences, Curtin University, Perth, Australia, 3Behavioural Ecology Laboratory, School of Molecular and Life Sciences, Curtin University, Perth, Australia
Biography:
Austin is a PhD candidate at Curtin’s Trace and Environmental DNA (TrEnD) laboratory, with a keen interest in terrestrial ecology, conservation and science communication. His PhD research explores the use of terrestrial eDNA as a monitoring tool for vertebrate populations in mine restoration areas within the Northern Jarrah Forests of Western Australia. Austin hopes his research will provide valuable insight into the importance of holistic rehabilitation of damaged landscapes and encourage the use of innovative monitoring techniques to assess restoration progress.
Abstract:
Environmental DNA (eDNA) surveys of terrestrial landscapes are a useful tool for monitoring biodiversity, particularly for rare and cryptic species that are difficult to monitor through conventional methods. Recently, a novel sampling approach has emerged, utilising paint rollers to swab surfaces such as bark, foliage, tree hollows and artificial habitats. Current DNA extraction methods for these types of samples is time consuming, equipment heavy and involves multiple handling steps which can increase contamination. Here we used rollers to swab a dog kennel and compared three DNA extraction approaches (water filtration, roller trimming and direct buffer) using two different platforms (QIAcube, Kingfisher). Extraction methods were evaluated based on cost, effort, DNA concentration and PCR result. The roller trim method, whereby a section of the roller was trimmed into a buffer, emerged as the optimal approach, producing the best PCR results and DNA concentrations while also being the most cost-efficient. The buffer-based methods were the least labour intensive but produced mediocre PCR results and DNA concentrations. Additionally, Kingfisher magnetic bead extractions generally outperformed QIAcube column-based DNA extractions across all categories. Ultimately, selecting the ideal DNA extraction method depends on logistical constraints in the field, such as the type of roller used, the availability of cold storage and project deadlines. Our results highlight the strengths and weaknesses of each approach, enabling researchers to make informed decisions around DNA extractions.