Invasive species are among the leading drivers of biodiversity loss and can have significant impacts on the global economy. Despite this, invasive species are spreading at an alarming rate as global connectivity and our reliance on international trade intensifies. The marine environment is no exception, with ballast water and biofouling of international shipping vessels being major vectors in the spread of invasive marine species.
During colonisation, invasive species often experience population bottlenecks, favouring traits that enhance rapid establishment and persistence in novel environments. Understanding population genetic information, including rates of clonality, population structure, and genetic diversity, are key to informing management strategies. Characterising invasive species spread dynamics and population connectivity across Australia is essential for guiding management and control efforts once species become established or to prevent further spread.
This presentation focuses on Didemnum vexillum, a highly invasive colonial ascidian recently introduced to Australia. Through a range of genetic approaches including mitogenome sequencing and SNP genotyping, we identified potential sources outside Australia, the connectivity between Australian populations, as well as rates of genetic diversity and clonality to better inform management of this marine invader.