Dr Jonathan W Lawley1, Dr Liz West1
1Ecological Service Professionals (ESP), Brisbane, Australia
Biography:
Jon is an ecologist and evolutionary biologist with over 10 years of experience in research, teaching, and consultancy. His research focuses on understanding aquatic biodiversity across ecological and evolutionary scales, combining field ecology, molecular biology, and data science to investigate how species evolve, interact, and respond to environmental change. Jon’s experience also involves teaching in various formal and informal settings, reviewing and editing academic texts, as well as programming and the application of emerging technologies to ecological research.
Abstract:
Jon is a Senior Aquatic Ecologist at Ecological Service Professionals. His recent work has focused on biodiversity monitoring, ecological modelling, environmental DNA (eDNA), and genomics, including the application of molecular and computational tools to biodiversity assessments and environmental management, habitat suitability modelling for conservation and restoration, and improving jellyfish identification and monitoring. Jon earned his PhD from Griffith University, Australia (2019 – 2023), his MSc in Zoology from the University of São Paulo, Brazil (2016 – 2018), and his BSc in Biological Sciences from the Federal University of Santa Catarina, Brazil (2009 – 2015).
Aquatic macroinvertebrate sampling underpins river condition assessments, but conventional collection and morphological identification are labour-intensive. Environmental DNA (eDNA) metabarcoding may offer a scalable alternative for preliminary assessments or targeted integration with conventional monitoring. We compared cytochrome c oxidase subunit I metabarcoding with replicated macroinvertebrate sampling at nine sites. Three water eDNA samples were collected per site using a pump and self-preserving filters, alongside five replicate macroinvertebrate samples in both bed and edge habitats, identified predominantly to family level. Detections were standardised to family level, and taxonomic richness, Plecoptera–Ephemeroptera–Trichoptera (PET) richness and Stream Invertebrate Grade Number Average Level (SIGNAL-2) were calculated and compared between methods.
Across all sites, eDNA detected 18 families, including three PET families, compared with 65 families, including seven PET families, using conventional sampling; seven and 54 families were exclusive to eDNA and conventional sampling, respectively. However, some results from both methods showed a strong positive correlation, particularly SIGNAL-2 score (edge: Pearson r = 0.74, p = 0.022; bed: r = 0.88, p = 0.002). While conventional methods required more time and cost, some outcomes were missed by the eDNA method that may be critical depending on the study objectives. Overall, the results supported the use of eDNA as a potentially cost-effective screening tool or component to monitor river condition that could reduce conventional laboratory processing while retaining samples for detailed taxonomic assessments. Improved eDNA reference libraries may also allow genus or species-level identifications that complement predominantly family-level identifications produced by conventional methods.