Genomic databanks provide robust assessment of invasive mosquito movement pathways and cryptic establishment

Abstract Biosecurity strategies that aim to restrict the spread of invasive pests can benefit from knowing where incursions have come and whether cryptic establishment has taken place. This knowledge be acquired with genomic databanks, by comparing genetic variation in incursion samples against reference samples. Here we use databanks characterise two mosquito species within Australia, observe how tracing methods perform when databank limited differentiation were collected tens generations ago. We used a deep learning method trace 2021 invasion Aedes aegypti Tennant Creek, Northern Territory, Townsville, Queensland, years Ae. albopictus specific islands Torres Strait. Tracing had high precision despite 30–70 separating samples, cross-validation assigned them correct origin 87% cases. Similar was not achieved PCAs, which performed particularly poorly for been subject strong drift effects. Targeted assays also provided additional information on Creek , this case Wolbachia infection data mitochondrial DNA variation. Patterns relatedness inbreeding indicated likely invaded one family while Strait independent no establishment. Our results highlight value remain informative over range biological conditions.