Dr Abinaya Meenakshisundaram1,2,3, Dr Luke Thomas2, Dr Shannon Corrigan3
1Oceans Institute, The University of Western Australia, Perth, Australia, 2Australian Institute of Marine Science (AIMS@UWA), Perth, Australia, 3Minderoo OceanOmics Centre at UWA, Perth, Australia
Biography:
Abi is a Research fellow at the University of Western Australia working on developing eDNA tools for individual tracking and population genetic monitoring of marine species with a special focus on whale sharks
Abstract:
Whale sharks are highly migratory and elusive, making long-term population genetic monitoring challenging using conventional tissue-based approaches. Environmental DNA (eDNA) offers an accessible alternative, but its application to population genetics has been limited by the difficulty of recovering sufficiently informative genetic markers from seawater samples. We have developed a panel of highly polymorphic microhaplotype markers to enable individual identification & population genetic analyses from eDNA. Microhaplotypes combine multiple closely linked SNPs within short nuclear DNA fragments, providing high discriminatory power and genetic resolution while remaining suitable for degraded eDNA.
Our preliminary work demonstrated that a 20-marker panel could recover individual genetic profiles and accurately reflect population-level genetic diversity from seawater collected behind free-swimming whale sharks. We have now expanded this approach with a new 66-marker panel to answer more complex questions, including genetic diversity, population structure, kinship and population size estimation from eDNA, while improving our ability to distinguish individual sharks genetically.
We are establishing a global collaboration of researchers monitoring whale shark aggregations, integrating eDNA collection into routine monitoring to enable genetic studies of aggregations where tissue sampling is restricted, impractical or unavailable. By combining archived tissue samples from Ningaloo Reef with eDNA collected locally and across global aggregations, we are building a global database of individual whale shark genetic profiles using this microhaplotype marker panel. This database will provide a foundation for identifying and tracking individuals across aggregations and investigating global connectivity using eDNA, establishing a scalable framework for long-term, non-invasive population genetic monitoring.